This document describes a method for designing a low noise RF amplifier for a 802.11b receiver application using Agilent's ADS design tools. The design procedure uses available gain and stability analysis to create an unconditionally stable amplifier circuit that minimizes noise and meets specifications. Key steps include analyzing the transistor's S-parameters, performing an EM simulation of the printed circuit board layout, and comparing the simulation and measurement results to verify the design meets requirements.
Uhf si ge hbt amplifier parameters and noise characteristicsmohamed albanna
This document describes the design and analysis of a two-stage UHF amplifier using SiGe HBT transistors. It discusses selecting the BFP640 transistor for its high frequency performance and low noise. CAD software was used to simulate the amplifier from DC to 5 GHz. Graphs show the amplifier's S-parameters meet requirements with S21 of 28dB, stability from 0.4-4 GHz, and noise factor below 1.9dB from 1-3 GHz. In conclusion, the amplifier design achieves high gain and low noise in the frequency range of 0.4-4 GHz using the SiGe BFP640 transistor.
The document summarizes the design of a low noise amplifier meeting specific gain, noise figure, return loss, and stability specifications. The amplifier was designed using a bipolar junction transistor with input and output matching networks composed of lumped elements. Simulation results showed the design met or nearly met all specifications except output return loss. Fabricated measurements matched simulations but did not fully meet specifications, potentially due to fabrication and component imperfections. Overall the amplifier performed well but could be improved with a higher bias point design.
The document discusses the design and implementation of a P-band RF low noise amplifier (LNA). It begins with an introduction to LNAs, explaining that their main function is to amplify weak signals while introducing minimal noise. It then discusses the use of pseudomorphic high electron mobility transistors (pHEMTs) for LNA design due to their ability to provide high gain and low noise figure. The document outlines the objectives and methodology for the project, which is to design an LNA with specifications including a frequency range of 50MHz-1GHz, gain of at least 22dB, noise figure below 4dB and input/output impedance of 50 ohms. It provides background on relevant LNA design concepts and
This document discusses the design and simulation of low noise amplifier (LNA) circuits with different matching circuit combinations at the input and output sides. It compares the performance of LNA circuits using 'T' and 'L' type matching networks. The circuits are simulated using Advanced Design System (ADS) software. Simulation results show that the T-L matching configuration provides better gain and noise figure than L-L, L-T, and T-T matching under stability conditions. Specifically, the T-L matching achieved a forward gain of 14.14 dB and noise figure of 1.81 dB, outperforming the other matching configurations. Stabilization circuits are also applied and analyzed.
DESIGN AND NOISE OPTIMIZATION OF RF LOW NOISE AMPLIFIER FOR IEEE STANDARD 802...VLSICS Design
Low noise amplifier is the front end block of radio-frequency receiver system. Its design required various characteristics such as power gain, noise figure, insertion losses and power consumption. In this paper we have proposed a single stage low noise amplifier design with high gain and low noise using inductive source degeneration topology for frequency range of 3 GHz to 7 GHz and also use the active biasing devices. A range of devices like inductors and capacitors are used to achieve 50 Ω input impedance with a low noise factor. The design process is simulated process is using Advance Design System (ADS) and implemented in TSMC 0.18 µm CMOS technology. A single stage low noise amplifier has a measured forward gain 25.4 dB and noise figure 2.2 dB at frequency 5.0 GHz.
This document describes the design and simulation of a 10 GHz low noise amplifier (LNA) using GaAs high electron mobility transistors (HEMTs). Three LNA designs are presented using different approaches for the matching and biasing networks: lumped elements, distributed elements, and radial stub elements. The best performing design uses distributed elements for matching and radial stubs for biasing. The simulation shows this LNA achieves a forward gain of 14.77 dB and noise figure of 0.775 dB at 10 GHz, demonstrating better performance than prior works. Input and output return losses were also improved compared to previous LNA designs at this frequency.
Low Noise Amplifier at 2 GHz using the transistor NE85639 in ADSKarthik Rathinavel
• Systematically designed a LNA and its biasing using non-ideal components such as Microstrip TLs resistors, capacitors etc.
• Calculated the S parameters of the Transistor and simulated the gain and bandwidth to be 10 dB and 1 GHz respectively.
• Achieved a Noise Figure of 3.2 dB and s11 of -20 dB in the final design.
A 2.4 ghz cmos lna input matching design using resistive feedback topology in...eSAT Journals
This document describes the design of a 2.4 GHz CMOS low noise amplifier (LNA) using a resistive feedback topology in 0.13μm technology. A series inductor input matching network is used to provide input matching. Simulation results show the LNA has a voltage gain (S21) of 28dB, noise figure of 2.2dB, input return loss (S11) of -10.7dB, third order intercept point (IIP3) of -22.4dBm, while consuming 4.8mW of power from a 1.2V supply. The resistive feedback topology improves performance over other designs by increasing gain and reducing the chip area required.
Uhf si ge hbt amplifier parameters and noise characteristicsmohamed albanna
This document describes the design and analysis of a two-stage UHF amplifier using SiGe HBT transistors. It discusses selecting the BFP640 transistor for its high frequency performance and low noise. CAD software was used to simulate the amplifier from DC to 5 GHz. Graphs show the amplifier's S-parameters meet requirements with S21 of 28dB, stability from 0.4-4 GHz, and noise factor below 1.9dB from 1-3 GHz. In conclusion, the amplifier design achieves high gain and low noise in the frequency range of 0.4-4 GHz using the SiGe BFP640 transistor.
The document summarizes the design of a low noise amplifier meeting specific gain, noise figure, return loss, and stability specifications. The amplifier was designed using a bipolar junction transistor with input and output matching networks composed of lumped elements. Simulation results showed the design met or nearly met all specifications except output return loss. Fabricated measurements matched simulations but did not fully meet specifications, potentially due to fabrication and component imperfections. Overall the amplifier performed well but could be improved with a higher bias point design.
The document discusses the design and implementation of a P-band RF low noise amplifier (LNA). It begins with an introduction to LNAs, explaining that their main function is to amplify weak signals while introducing minimal noise. It then discusses the use of pseudomorphic high electron mobility transistors (pHEMTs) for LNA design due to their ability to provide high gain and low noise figure. The document outlines the objectives and methodology for the project, which is to design an LNA with specifications including a frequency range of 50MHz-1GHz, gain of at least 22dB, noise figure below 4dB and input/output impedance of 50 ohms. It provides background on relevant LNA design concepts and
This document discusses the design and simulation of low noise amplifier (LNA) circuits with different matching circuit combinations at the input and output sides. It compares the performance of LNA circuits using 'T' and 'L' type matching networks. The circuits are simulated using Advanced Design System (ADS) software. Simulation results show that the T-L matching configuration provides better gain and noise figure than L-L, L-T, and T-T matching under stability conditions. Specifically, the T-L matching achieved a forward gain of 14.14 dB and noise figure of 1.81 dB, outperforming the other matching configurations. Stabilization circuits are also applied and analyzed.
DESIGN AND NOISE OPTIMIZATION OF RF LOW NOISE AMPLIFIER FOR IEEE STANDARD 802...VLSICS Design
Low noise amplifier is the front end block of radio-frequency receiver system. Its design required various characteristics such as power gain, noise figure, insertion losses and power consumption. In this paper we have proposed a single stage low noise amplifier design with high gain and low noise using inductive source degeneration topology for frequency range of 3 GHz to 7 GHz and also use the active biasing devices. A range of devices like inductors and capacitors are used to achieve 50 Ω input impedance with a low noise factor. The design process is simulated process is using Advance Design System (ADS) and implemented in TSMC 0.18 µm CMOS technology. A single stage low noise amplifier has a measured forward gain 25.4 dB and noise figure 2.2 dB at frequency 5.0 GHz.
This document describes the design and simulation of a 10 GHz low noise amplifier (LNA) using GaAs high electron mobility transistors (HEMTs). Three LNA designs are presented using different approaches for the matching and biasing networks: lumped elements, distributed elements, and radial stub elements. The best performing design uses distributed elements for matching and radial stubs for biasing. The simulation shows this LNA achieves a forward gain of 14.77 dB and noise figure of 0.775 dB at 10 GHz, demonstrating better performance than prior works. Input and output return losses were also improved compared to previous LNA designs at this frequency.
Low Noise Amplifier at 2 GHz using the transistor NE85639 in ADSKarthik Rathinavel
• Systematically designed a LNA and its biasing using non-ideal components such as Microstrip TLs resistors, capacitors etc.
• Calculated the S parameters of the Transistor and simulated the gain and bandwidth to be 10 dB and 1 GHz respectively.
• Achieved a Noise Figure of 3.2 dB and s11 of -20 dB in the final design.
A 2.4 ghz cmos lna input matching design using resistive feedback topology in...eSAT Journals
This document describes the design of a 2.4 GHz CMOS low noise amplifier (LNA) using a resistive feedback topology in 0.13μm technology. A series inductor input matching network is used to provide input matching. Simulation results show the LNA has a voltage gain (S21) of 28dB, noise figure of 2.2dB, input return loss (S11) of -10.7dB, third order intercept point (IIP3) of -22.4dBm, while consuming 4.8mW of power from a 1.2V supply. The resistive feedback topology improves performance over other designs by increasing gain and reducing the chip area required.
A 2.4 ghz cmos lna input matching design using resistive feedback topology in...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
This document summarizes the design and development of a high power amplifier at 3.4 GHz for use in ranging transponders. It describes the design approach, including impedance matching networks to maximize power transfer. Simulation results show the power amplifier achieved over 27 dB of gain and met input and output return loss specifications of less than -10 dB after impedance matching. Biasing network design allowed the power amplifier to achieve 54% efficiency and output over 1 W of RF power. The document provides a literature review of similar power amplifier designs and aims to guide the design of a high power amplifier at 3.4 GHz suitable for use in ranging transponder applications.
Design of 10 to 12 GHz Low Noise Amplifier for Ultrawideband (UWB) SystemIJECEIAES
Balanced amplifier is the structure proposed in this article, it provides better performance. In fact, the single amplifier meets the specification for noise figure and gain but fails to meet the return loss specification due to the large mis-matches on the input & outputs. To overcome this problem one solution is to use balanced amplifier topography. In this paper, a wide-band and highgain microwave balanced amplifier constituted with branch line coupler circuit is proposed. The amplifier is unconditionally stable in the band [9-13] GHz where the gain is about 20dB. The input reflection (S11) and output return loss (S22) at 11 GHz are -33.4dB and -33.5dB respectively.
Design and Implementation of LNA at 900MHz for GSM applicationsAbdus Sami
This document summarizes the design, simulation, and implementation of a low noise amplifier (LNA) operating at 900MHz for GSM applications. The LNA was designed to have a gain of over 10dB and noise figure of less than 4dB over a 300MHz bandwidth. Simulation results showed a gain of 12dB at the center frequency with variation of ±1.3dB across the bandwidth. The noise figure was 3.9dB. The LNA achieved very high linearity and unconditional stability. The report describes the circuit design, matching network, stability considerations, and hardware implementation through layout generation and component selection.
Multisim design and simulation of 2.2 g hz lna for wireless communicationVLSICS Design
This paper presents the work done on the design and simulation of a high frequency low noise amplifier for
wireless communication. The purpose of the amplifier is to amplify the received RF path of a wireless
network. With high gain, high sensitivity and low noise using Bipolar Junction transistor (BJT). The design
methodology requires analysis of the transistor for stability, proper matching, network selection and
fabrication. The BJT transistor was chosen for the design of the LNA due to its low noise and good gain at
high frequency. These properties were confirmed using some measurement techniques including Network
Analyzer, frequency analyzer Probe and Oscilloscope for the simulation and practical testing of the
amplifier to verify the performance of the designed High frequency Low noise amplifier. The design goals
of noise figure of 0.52dB-0.7dB and bias conditions are Vcc = 3.5 V and Icc= 55 mA to produce 16.8 dB
gain across the 0.4–2.2GHz band.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
The document summarizes a seminar presentation on low noise amplifiers (LNAs). It discusses that LNAs are key components for amplifying weak signals from antennas. It then outlines two design methods for LNAs - lumped parameter and distributed parameter. Lumped parameter treats active devices and input/output networks separately, while distributed parameter considers them together using Smith charts. It also discusses using matching networks between antennas and LNAs and between LNAs and mixers to provide proper terminations and ensure optimal noise performance, stability and power matching. Finally, it compares narrowband and wideband LNAs and their differences in circuit complexity, noise performance, and achieving bandpass amplification.
This document describes the design of a low noise amplifier (LNA) for wideband wireless receivers operating in the S-band frequency range of 2-4 GHz. It first discusses designing an LNA using lumped elements, achieving a maximum gain of 10 dB at 2.5 GHz and minimum noise figure of 2.4 dB at 4 GHz. It then presents an improved design using microstrip matching networks, obtaining a lower minimum noise figure of 0.424 dB at 2.6 GHz and higher maximum gain of 10.84 dB at 2.4 GHz. The microstrip design demonstrates better performance for noise figure and gain across the 2-4 GHz band compared to the lumped element approach.
This document presents the design of a wideband direct downconversion receiver consisting of a differential common gate low-noise amplifier (LNA) and two Gilbert Cell mixers. The design achieves the specifications of operating from 2.4-5 GHz with a power consumption of 41.45 mW while meeting the requirements for input matching, conversion gain, noise figure, P1dB, and PIIP3. Theoretical analyses are presented and compared to simulation results, showing good agreement between the calculated and simulated values of input matching, conversion gain, and noise figure. References are provided for the inspiration and design of the LNA and mixers.
This document summarizes Sage's implementation of the ITU-T G.168 test suite for evaluating digital echo cancellers. It describes the test configuration involving Sage's echo generator and G.168 tester devices. It provides an overview of the 15 tests implemented, covering areas like convergence testing, steady-state residual echo levels, and performance under double-talk conditions. For each test, it outlines the common procedures and signals involved, as well as any unique test-specific procedures or results.
This document describes the design and analysis of a single-ended inductively degenerated interstage matched common-source cascode CMOS low noise amplifier (LNA). The LNA is implemented using a 90nm CMOS process. It employs a cascode topology with single-ended source degeneration using an inductor to achieve high gain. An interstage inductor between the common source and common gate stages is used to further increase the overall gain. Simulation results show the LNA has a noise figure of 1.986dB at 2.4GHz, a voltage gain of 19.1dB, and operates with low noise and high gain as required for applications such as wireless communications.
This document discusses the design of a common-gate broadband low-noise amplifier (LNA) with the objectives of having at least 10 dB of gain, less than 5 dB of noise figure, and a bandwidth of at least 5 GHz. It presents the schematic and layout of the LNA, showing tradeoffs between bandwidth and gain related to the transistor width. Test results found a mid-band gain of 10 dB, mid-band noise figure of 5.4 dB, and a high-frequency cutoff of 4.6 GHz, meeting most objectives. The LNA is expected to be fabricated soon and may be used for a radio's front end.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
Adding an external low noise amplifier (LNA) can improve receiver sensitivity by reducing its noise figure. However, this comes at the cost of reduced signal handling capability and dynamic range due to a lower third-order intercept point (IIP3). While an external LNA may increase sensitivity by a few dB, it also reduces the receiver's IIP3 by 15 dB, making it more susceptible to interference. Therefore, simply adding an LNA does not guarantee better performance, as the receiver may become unusable except in very clean RF environments.
This document investigates the bit error rate (BER) performance of MIMO systems with different numbers of transmitting antennas. It begins with background on fading in wireless channels and how MIMO can be used to combat fading using multiple antennas. It then describes the Alamouti space-time coding scheme for two transmitting antennas. Simulation results show that BER decreases with increasing SNR and increasing number of transmitting antennas, with lower BER achieved using 4 transmitting antennas compared to 2 or 3. The conclusion is that MIMO systems with more transmitting antennas generally provide better performance due to transmitting more data and giving the receiver more ability to recover the transmitted data.
This document presents a proposed low noise amplifier (LNA) design approach and its simulation results. It begins with an introduction of LNA applications and design challenges. It then discusses noise figure optimization and different LNA topologies. A cascode common source common gate topology is proposed that works for low power supplies. Simulation results show the proposed LNA achieves a noise figure of 1.1dB, power gain of 23dB, and input and output matching better than -13.5dB and -21dB respectively, while consuming low power of 8.4mW. In conclusion, the LNA meets design goals of low noise and power for a 0.7V supply.
This document describes research on developing multi-functional and reconfigurable microwave control devices. It discusses a proposed novel broadband tunable rat-race coupler with increased bandwidth and tuning ratio, as well as a compact variable power divider design using integrated transformers for CMOS implementation. It also proposes a varactor-tuned variable attenuator design with wide tuning range and flat insertion loss for applications requiring signal power control. Measurement results demonstrate tuning capabilities and good performance over bandwidth for both designs.
This paper presents a model for Chinese word segmentation that integrates it as part of sentence analysis using a parser. The model achieves high accuracy by resolving most ambiguities at the lexical level using dictionary information, but handles cases requiring syntactic context in the parsing process. The complexity usually associated with parsing is reduced by pruning implausible segmentations prior to parsing. The approach is implemented in a natural language understanding system developed at Microsoft Research.
This chapter outlines the social, political, and economic importance of football. Socially, football brings communities and nations together in support of clubs and during international tournaments. Politically, it promotes physical activity and keeps youth occupied. Economically, football is worth billions and contributes significantly to many national economies through related business. The chapter establishes why analyzing football through a political economic lens is important given its widespread social, political, and economic impacts.
This document proposes two music video ideas for promoting an artist. Idea 1 involves shooting a video for the song "The Big Unknown" featuring a woman lip syncing while dressed in a white dress surrounded by water and woods. Floating objects would be incorporated to represent a dream-like theme. Idea 2 involves shooting a video for Aretha Franklin's "Say A Little Prayer" featuring a transvestite performing at a pub to an uninterested crowd. The video would be shot backwards and reveal the character's struggle with their sexuality. Both ideas aim to positively represent the artists and their music in an alternative or thought-provoking way.
This document outlines the business objectives and strategy for a landscaping company. The objectives include achieving 60% annual gross margin, 20% market share in homes over $500,000 within 3 years, breaking even in the second quarter, and becoming the top choice for landscaping design, installation, and management services on the island. The business strategy focuses on differentiation by targeting a narrow market segment of luxury homeowners and emphasizing word-of-mouth referrals. Key aspects of differentiation include using premium materials and providing high-quality, customized services and customer intimacy. Sales projections estimate $956,903 in gross sales and 60% gross margin.
A 2.4 ghz cmos lna input matching design using resistive feedback topology in...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
This document summarizes the design and development of a high power amplifier at 3.4 GHz for use in ranging transponders. It describes the design approach, including impedance matching networks to maximize power transfer. Simulation results show the power amplifier achieved over 27 dB of gain and met input and output return loss specifications of less than -10 dB after impedance matching. Biasing network design allowed the power amplifier to achieve 54% efficiency and output over 1 W of RF power. The document provides a literature review of similar power amplifier designs and aims to guide the design of a high power amplifier at 3.4 GHz suitable for use in ranging transponder applications.
Design of 10 to 12 GHz Low Noise Amplifier for Ultrawideband (UWB) SystemIJECEIAES
Balanced amplifier is the structure proposed in this article, it provides better performance. In fact, the single amplifier meets the specification for noise figure and gain but fails to meet the return loss specification due to the large mis-matches on the input & outputs. To overcome this problem one solution is to use balanced amplifier topography. In this paper, a wide-band and highgain microwave balanced amplifier constituted with branch line coupler circuit is proposed. The amplifier is unconditionally stable in the band [9-13] GHz where the gain is about 20dB. The input reflection (S11) and output return loss (S22) at 11 GHz are -33.4dB and -33.5dB respectively.
Design and Implementation of LNA at 900MHz for GSM applicationsAbdus Sami
This document summarizes the design, simulation, and implementation of a low noise amplifier (LNA) operating at 900MHz for GSM applications. The LNA was designed to have a gain of over 10dB and noise figure of less than 4dB over a 300MHz bandwidth. Simulation results showed a gain of 12dB at the center frequency with variation of ±1.3dB across the bandwidth. The noise figure was 3.9dB. The LNA achieved very high linearity and unconditional stability. The report describes the circuit design, matching network, stability considerations, and hardware implementation through layout generation and component selection.
Multisim design and simulation of 2.2 g hz lna for wireless communicationVLSICS Design
This paper presents the work done on the design and simulation of a high frequency low noise amplifier for
wireless communication. The purpose of the amplifier is to amplify the received RF path of a wireless
network. With high gain, high sensitivity and low noise using Bipolar Junction transistor (BJT). The design
methodology requires analysis of the transistor for stability, proper matching, network selection and
fabrication. The BJT transistor was chosen for the design of the LNA due to its low noise and good gain at
high frequency. These properties were confirmed using some measurement techniques including Network
Analyzer, frequency analyzer Probe and Oscilloscope for the simulation and practical testing of the
amplifier to verify the performance of the designed High frequency Low noise amplifier. The design goals
of noise figure of 0.52dB-0.7dB and bias conditions are Vcc = 3.5 V and Icc= 55 mA to produce 16.8 dB
gain across the 0.4–2.2GHz band.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
The document summarizes a seminar presentation on low noise amplifiers (LNAs). It discusses that LNAs are key components for amplifying weak signals from antennas. It then outlines two design methods for LNAs - lumped parameter and distributed parameter. Lumped parameter treats active devices and input/output networks separately, while distributed parameter considers them together using Smith charts. It also discusses using matching networks between antennas and LNAs and between LNAs and mixers to provide proper terminations and ensure optimal noise performance, stability and power matching. Finally, it compares narrowband and wideband LNAs and their differences in circuit complexity, noise performance, and achieving bandpass amplification.
This document describes the design of a low noise amplifier (LNA) for wideband wireless receivers operating in the S-band frequency range of 2-4 GHz. It first discusses designing an LNA using lumped elements, achieving a maximum gain of 10 dB at 2.5 GHz and minimum noise figure of 2.4 dB at 4 GHz. It then presents an improved design using microstrip matching networks, obtaining a lower minimum noise figure of 0.424 dB at 2.6 GHz and higher maximum gain of 10.84 dB at 2.4 GHz. The microstrip design demonstrates better performance for noise figure and gain across the 2-4 GHz band compared to the lumped element approach.
This document presents the design of a wideband direct downconversion receiver consisting of a differential common gate low-noise amplifier (LNA) and two Gilbert Cell mixers. The design achieves the specifications of operating from 2.4-5 GHz with a power consumption of 41.45 mW while meeting the requirements for input matching, conversion gain, noise figure, P1dB, and PIIP3. Theoretical analyses are presented and compared to simulation results, showing good agreement between the calculated and simulated values of input matching, conversion gain, and noise figure. References are provided for the inspiration and design of the LNA and mixers.
This document summarizes Sage's implementation of the ITU-T G.168 test suite for evaluating digital echo cancellers. It describes the test configuration involving Sage's echo generator and G.168 tester devices. It provides an overview of the 15 tests implemented, covering areas like convergence testing, steady-state residual echo levels, and performance under double-talk conditions. For each test, it outlines the common procedures and signals involved, as well as any unique test-specific procedures or results.
This document describes the design and analysis of a single-ended inductively degenerated interstage matched common-source cascode CMOS low noise amplifier (LNA). The LNA is implemented using a 90nm CMOS process. It employs a cascode topology with single-ended source degeneration using an inductor to achieve high gain. An interstage inductor between the common source and common gate stages is used to further increase the overall gain. Simulation results show the LNA has a noise figure of 1.986dB at 2.4GHz, a voltage gain of 19.1dB, and operates with low noise and high gain as required for applications such as wireless communications.
This document discusses the design of a common-gate broadband low-noise amplifier (LNA) with the objectives of having at least 10 dB of gain, less than 5 dB of noise figure, and a bandwidth of at least 5 GHz. It presents the schematic and layout of the LNA, showing tradeoffs between bandwidth and gain related to the transistor width. Test results found a mid-band gain of 10 dB, mid-band noise figure of 5.4 dB, and a high-frequency cutoff of 4.6 GHz, meeting most objectives. The LNA is expected to be fabricated soon and may be used for a radio's front end.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
Adding an external low noise amplifier (LNA) can improve receiver sensitivity by reducing its noise figure. However, this comes at the cost of reduced signal handling capability and dynamic range due to a lower third-order intercept point (IIP3). While an external LNA may increase sensitivity by a few dB, it also reduces the receiver's IIP3 by 15 dB, making it more susceptible to interference. Therefore, simply adding an LNA does not guarantee better performance, as the receiver may become unusable except in very clean RF environments.
This document investigates the bit error rate (BER) performance of MIMO systems with different numbers of transmitting antennas. It begins with background on fading in wireless channels and how MIMO can be used to combat fading using multiple antennas. It then describes the Alamouti space-time coding scheme for two transmitting antennas. Simulation results show that BER decreases with increasing SNR and increasing number of transmitting antennas, with lower BER achieved using 4 transmitting antennas compared to 2 or 3. The conclusion is that MIMO systems with more transmitting antennas generally provide better performance due to transmitting more data and giving the receiver more ability to recover the transmitted data.
This document presents a proposed low noise amplifier (LNA) design approach and its simulation results. It begins with an introduction of LNA applications and design challenges. It then discusses noise figure optimization and different LNA topologies. A cascode common source common gate topology is proposed that works for low power supplies. Simulation results show the proposed LNA achieves a noise figure of 1.1dB, power gain of 23dB, and input and output matching better than -13.5dB and -21dB respectively, while consuming low power of 8.4mW. In conclusion, the LNA meets design goals of low noise and power for a 0.7V supply.
This document describes research on developing multi-functional and reconfigurable microwave control devices. It discusses a proposed novel broadband tunable rat-race coupler with increased bandwidth and tuning ratio, as well as a compact variable power divider design using integrated transformers for CMOS implementation. It also proposes a varactor-tuned variable attenuator design with wide tuning range and flat insertion loss for applications requiring signal power control. Measurement results demonstrate tuning capabilities and good performance over bandwidth for both designs.
This paper presents a model for Chinese word segmentation that integrates it as part of sentence analysis using a parser. The model achieves high accuracy by resolving most ambiguities at the lexical level using dictionary information, but handles cases requiring syntactic context in the parsing process. The complexity usually associated with parsing is reduced by pruning implausible segmentations prior to parsing. The approach is implemented in a natural language understanding system developed at Microsoft Research.
This chapter outlines the social, political, and economic importance of football. Socially, football brings communities and nations together in support of clubs and during international tournaments. Politically, it promotes physical activity and keeps youth occupied. Economically, football is worth billions and contributes significantly to many national economies through related business. The chapter establishes why analyzing football through a political economic lens is important given its widespread social, political, and economic impacts.
This document proposes two music video ideas for promoting an artist. Idea 1 involves shooting a video for the song "The Big Unknown" featuring a woman lip syncing while dressed in a white dress surrounded by water and woods. Floating objects would be incorporated to represent a dream-like theme. Idea 2 involves shooting a video for Aretha Franklin's "Say A Little Prayer" featuring a transvestite performing at a pub to an uninterested crowd. The video would be shot backwards and reveal the character's struggle with their sexuality. Both ideas aim to positively represent the artists and their music in an alternative or thought-provoking way.
This document outlines the business objectives and strategy for a landscaping company. The objectives include achieving 60% annual gross margin, 20% market share in homes over $500,000 within 3 years, breaking even in the second quarter, and becoming the top choice for landscaping design, installation, and management services on the island. The business strategy focuses on differentiation by targeting a narrow market segment of luxury homeowners and emphasizing word-of-mouth referrals. Key aspects of differentiation include using premium materials and providing high-quality, customized services and customer intimacy. Sales projections estimate $956,903 in gross sales and 60% gross margin.
Dynamic Lexical Acquisition in Chinese Sentence AnalysisAndi Wu
This document discusses a method for dynamically acquiring lexical information during sentence analysis in order to improve the coverage of a parser without requiring manual dictionary editing. New words and attributes are proposed based on contextual templates and accepted or rejected based on whether they are needed to parse sentences successfully. Accepted proposals are stored in auxiliary lexicons which can then be combined with the main lexicon to improve parsing of future sentences, especially in domain-specific texts. Evaluation on a technical manual corpus showed the method significantly improved parsing accuracy by recognizing new words and attributes.
Course note, The course supported by Mevlana Exchange Programme was presented at the Tourism Department of Economy Faculty of Tetova State Unıversity, Macedonia in May 11-15, 2015
aplicaciones para realizar deporte o entrenaremmanuelber
Haiku Deck is a presentation platform that allows users to create Haiku-style slideshows. The document encourages the reader to get started creating their own Haiku Deck presentation on SlideShare by providing a link to do so. It pitches the idea of making Haiku Deck presentations without providing many details about the platform itself.
The document summarizes a redesign project for the UCSD Guardian newspaper stands. It discusses researching current newspaper distribution problems like many papers going unread. Testing new stand designs in high traffic areas showed more papers being picked up from an updated stand. The project team developed potential stand design solutions and plans to track readership by location and stand type in a spreadsheet. The goal is to improve newspaper accessibility and visibility while preventing waste to better distribute the 10,000 papers printed weekly.
The document discusses the six basic principles of the US Constitution: Popular Sovereignty, which holds that the power to govern belongs to the people; Separation of Powers, which divides government among branches; Checks and Balances, a system where each branch limits the others' power; Federalism, which allocates powers between national and state governments; Supremacy of National Laws, where federal law overrides state law; and Civilian Control of Government, ensuring elected officials control the military. It provides details on each principle and how they are reflected in the Constitution.
This short document promotes creating presentations using Haiku Deck, a tool for making slideshows. It encourages the reader to get started making their own Haiku Deck presentation and sharing it on SlideShare. In a single sentence, it pitches the idea of using Haiku Deck to easily design presentations.
This document describes a study that used computational models of the auditory nerve (AN) and dorsal cochlear nucleus (DCN) to simulate the effects of auditory trauma. The study input impaired AN models into a DCN model to generate response maps. Response maps from healthy and impaired models were compared. Impaired models showed elevated thresholds, broadened tuning curves, and shifted rate-level functions consistent with physiological data. DCN maps from impaired models decreased excitation and inhibition regions and increased spontaneous activity, modeling tinnitus. The models provide insight into hearing loss and the auditory system.
This short document promotes creating presentations using Haiku Deck on SlideShare. It encourages the reader to get started making their own Haiku Deck presentation by simply clicking the "GET STARTED" button provided. In just one sentence, it pitches presentation creation using Haiku Deck on SlideShare.
Las actividades de la semana incluyen prácticas sobre habilidades de autoayuda y autonomía (HHAA). Estas prácticas ayudarán a los estudiantes a desarrollar destrezas importantes para la vida diaria como cocinar, limpiar y hacer compras. El enfoque está en fomentar la independencia a través de la práctica de tareas cotidianas.
Patent Office in India publishes patent and design registration information on a weekly basis (on Friday each week). This is public notification, enabling the public to take appropriate action if desired. Data published on September 18th, 2015. Data sourced from Indian Patent Office website by InvnTree IP Service Pvt Ltd, a patent services company based in Bangalore
The document provides two easy tips for starting the day productively: 1) Take 6 minutes in the morning without electronics to focus on gratitude, blessing others, and visualizing your goals. 2) Focus your thoughts on positive topics like past successes instead of problems to improve your mood and productivity. The author argues that successful people develop habits like these tips and that focusing your mind in a positive way programs your brain for success.
Building impedance matching network based on s parameter from manufacturerJournal Papers
The document describes a method for building an impedance matching network for a transistor using S-parameter data and optimization tools in ADS simulation software. The transistor of interest operates from 220-270 MHz, where reference designs are unavailable. Input and output impedances are extracted from S-parameter files. An existing matching network design at a nearby frequency is used as a starting point. Optimization replaces ideal components with real ones, achieving over 30 dB return loss while degrading slightly from the ideal simulation. The method demonstrates synthesizing a matching network when reference designs are unavailable.
Building impedance matching network based on s parameter from manufacturerConference Papers
The document describes a method for building an impedance matching network for a transistor using S-parameter data and optimization tools in ADS simulation software. The transistor of interest operates from 220-270MHz, where no reference design exists. The method extracts the input and output impedances from S-parameter files and uses a known matching network at a nearby frequency as a starting point. Optimization in ADS is used to synthesize matching networks with ideal components that improve return loss and gain. Simulations with real component values show some performance degradation but remain acceptable. The matching networks can then be used for PCB fabrication.
1) The document describes the design and simulation of a linear amplifier that operates in the C band frequency range of 5-6 GHz.
2) A Class A amplifier design approach was used to ensure linearity at higher frequencies. A GaAs FET transistor was selected and biased in its linear region.
3) Input and output matching networks were designed using S-parameter simulations. Multiple transistor stages were cascaded to increase the gain to 30 dB.
4) Simulation results showed a gain of 19.241 dB, S-parameters, stability above 1, and a noise figure of around 3 dB as expected for a low noise pre-amplifier.
Design of 17-Bit Audio Band Delta-Sigma Analog to Digital ConverterKarthik Rathinavel
• Systematically designed a delta sigma ADC with CIFF modular architecture in MATLAB Simulink with an ENOB of 19-bits.
• Designed a decimation filter to remove noise in the digital output of the delta sigma modulator.
• Observed the effect of non-idealities on the modulator such as finite gain, finite bandwidth, slew rate, analog noise and capacitor mismatch.
This document describes an FPGA-based passive K-Delta-1-Sigma (KD1S) sigma-delta modulator designed and tested by researchers. The modulator uses eight phase-shifted clocks on an FPGA to achieve an effective sampling rate of 450 MHz without active analog components. Testing showed the design achieved a peak SNR of 58 dB and ENOB of 9.3 bits at this high sampling rate, demonstrating the benefits of this passive approach for wide bandwidth applications.
This document summarizes the design, implementation, and characterization of a 22 W, 65% efficient Doherty power amplifier at 3.5 GHz for WiMAX applications. The amplifier uses a GaN HEMT and implements a class AB main amplifier and class C peak amplifier. Measurements found an output power of 22 W with an efficiency over 55% from saturation to 6 dB input back-off. The design achieved good agreement between simulated and measured results.
In present stereo audio system is a most popular audio system for different purposes. Now a day’s stereo system is commonly used in communication and other purposes. Moreover Normalized Least Mean Square (NLMS) based adaptive filtering is an effective filtering process in case of communication and other applications. However adaptive filtering is an adaptive filter process to cancel out the noise from audio signal successfully. Hence the main objective of this paper is to design a NLMS adaptive filter which cancels out the noise from a noisy wave format stereo audio file. Moreover by varying the order of the adaptive filter (such as 8th, 16th, 32th and 64th), the performance of the NMLS adaptive filtered signal with respect to reference and noisy stereo audio signal are analyzed as well.
Wideband power amplifier based on Wilkinson power divider for s-band satellit...journalBEEI
This paper presents design and simulation of wideband power amplifier based on multi-section Wilkinson power divider. Class-A topology and ATF-511P8 transistor have been used. Advanced Design System (ADS) software used to simulate the designed power amplifier. The simulation results show an input return loss (S11)<-10dB, gain (S21)>10 dB over the entire bandwidth, and an output power around 28dBm at the Centre frequency of 3GHz. The designed amplifier is stable over the entire bandwidth (K>1). Inter-modulation distortion is -65.187dBc which is less than -50dBc. The designed amplifier can be used for the microwave applications which include weather radar, satellite communication, wireless networking, mobile, and TV.
This document describes the design of a linear low noise microwave amplifier circuit with maximum transducer gain. Key steps included:
1) Calculating S-parameters of the transistor amplifier model and determining the input and output matching networks.
2) Simulating the ideal circuit in AWR software and calculating the theoretical maximum gain.
3) Translating the design to a microstrip circuit and simulating it, achieving a gain close to the theoretical maximum.
4) Testing the design for stability using the μ-parameter and confirming it is unconditionally stable at the desired frequency.
Design of Low Noise Amplifier for Wimax ApplicationIOSR Journals
The document describes the design of a low noise amplifier (LNA) for WiMAX applications operating in the 3.3-3.8 GHz range. It discusses testing the transistor to check for stability and gain. Input and output matching is performed using stub matching networks to achieve low noise figure and high gain. A passive biasing circuit is designed using resistors and capacitors. Two LNA techniques, feedback amplifier and balanced amplifier, are simulated to find the best performance; the feedback amplifier provides a nominal noise figure of 1.02 dB and gain of 12 dB.
This document summarizes an adaptive output stage Class D audio amplifier designed for high efficiency over a wide range of output powers. The design uses multiple output stages selected by a finite state machine to optimize efficiency based on the output power level. At low output powers, switching losses dominate, so a low-power stage is selected. At medium powers, both switching and conduction losses are significant, selecting a medium-power stage. At high powers, conduction losses dominate, selecting a high-power stage. A feed-forward technique is used to enhance power supply rejection. Simulation results show over 90% efficiency across output powers and a power supply rejection ratio of 69dB.
Adaptive Design of FPGA-based Direct Digital Frequency Synthesizer to Optimiz...IDES Editor
A Direct Digital Frequency Synthesizer designed
core is implemented and validated in this paper. This
electronics paper proposed the details of programming model
optimal and feasible architecture of Direct Digital
Synthesizer that eliminates the need for the manual tuning
and tweaking related to component aging and temperature
drift in analog synthesizer solutions. A Direct Digital
Synthesizer play a vital role in Digital frequency Down
Conversion in such an application, the DDC (Digital Down
converter) has become a cornerstone technology in
communication systems. Here, the design of Digital Frequency
Synthesizer gives an output with specified frequency and
phase which is adjustable at runtime. This paper also evaluates
the performance of DDS under various programming
parameters and the performance is implemented on Virtex II
Pro.
Welcome to International Journal of Engineering Research and Development (IJERD)IJERD Editor
This document provides a tutorial on designing microwave amplifiers using CAD software. It discusses:
1) The key steps in microwave amplifier design including selecting an active device, biasing it, characterizing the device, analyzing stability, and implementing matching networks.
2) Methods for stability analysis including the Rollett K-factor test, source-load circle graphical analysis on the Smith Chart, and evaluating the reflection coefficients Γin and Γout.
3) How CAD tools like AWR's Microwave Office can be used to design microwave amplifiers by simulating the circuit and evaluating performance based on the device specifications and design parameters.
This document describes the design, implementation, and simulation of a 2-GHz low noise amplifier (LNA). The LNA is designed using both lumped elements and distributed elements approaches. Key steps in the design process are discussed, including the use of the MESFET transistor, input and output matching networks, and performance analysis using the Smith Chart. The LNA provides a noise figure of 0.358 dB, gain of 16.778 dB, and meets other specifications. Simulation results show that the lumped elements approach achieves better performance than the distributed elements approach. The document outlines the design process and evaluation of LNAs to meet requirements for wireless communication systems.
This document describes the design of a 2.4GHz CMOS power amplifier for wireless communication using a 130nm technology. It begins with an introduction to power amplifiers and their importance in wireless transmitters for amplifying transmitted signals. It then reviews previous work on power amplifier design using different technologies. The document proposes a class-B power amplifier design using a 130nm technology to achieve a gain of more than 15dB. Simulation results show the designed class-B power amplifier meets the frequency response requirement at 2.4GHz with a gain of 67.321dB. The power amplifier is designed to operate with a power supply voltage range of 1.3-3V, making it suitable for battery-powered portable electronics and wireless communication
PARASITIC-AWARE FULL PHYSICAL CHIP DESIGN OF LNA RFIC AT 2.45GHZ USING IBM 13...Ilango Jeyasubramanian
This document summarizes the design of a low noise amplifier (LNA) operating at 2.45GHz. The LNA uses a cascode topology with inductive source degeneration implemented in a 120nm CMOS process. Simulation results show the LNA meets specifications for gain, return loss, output match, noise figure, and linearity over 2.4-2.5GHz. Variability analysis demonstrates performance remains within specifications with +/-10% parameter variations. The compact layout achieves good matching through careful device placement and use of appropriate passive components to minimize parasitics.
IRJET- Analysis of Low Noise Amplifier using 45nm CMOS TechnologyIRJET Journal
This document summarizes a research paper that analyzes the design of a low noise amplifier (LNA) using 45nm CMOS technology. The proposed LNA design consists of a common gate amplifier as the input stage, an active inductor, and a common drain amplifier as the output stage. Pre-simulation and post-simulation analyses were conducted. The results showed a gain of 13.631 dB, bandwidth of 10.71 KHz, power consumption of 35.31uW, and a small chip area of 0.6um2, demonstrating it is a low power LNA suitable for the intended application.
Performance analysis of High Speed ADC using SR F/FIOSR Journals
This document analyzes the performance of a high-speed analog-to-digital converter (ADC) using a sense amplifier flip-flop (SAFF). It describes the design of a double tail current sense amplifier-based comparator combined with a symmetric set-reset (SR) latch. This design offers faster response and more stable output compared to conventional designs. Simulation results in 180nm and 90nm show the proposed SAFF has lower delay between outputs and lower power dissipation. Specifically, the delay between outputs is 0.029ns in 180nm and 0.011ns in 90nm for the proposed design, providing faster and more stable operation for high-speed ADCs compared to traditional comparator and latch designs.
Wireless communication system are developing rapidly, due to which new standards like WIMAX and 4G Long Term Evaluating(LTE) with a purpose of achieving high data rate result in high end applications such as high speed internet, video conferences and broadband width. These applications require mobile base stations at the transmitter as well as at receiver (T/R) to support features like multiple bands, multiple modes, higher BW and less power consumption. The design and implementation of multi-standard transceivers for wireless mobile system is very complex task. In this paper we discuss the design of a wider band Doherty Amplifier, which operational frequency of 3 GHz to 3.75 GHz.
First order sigma delta modulator with low-power consumption implemented in a...eSAT Journals
Abstract
This paper presents a design of a switched-capacitor discrete time 1st order Delta-Sigma modulator used for a resolution of 8 bits
Sigma-Delta analog to digital converter. For lower power consumption, the use of operational transconductance amplifier is
necessary in order to provide wide output voltage swing and moderate DC gain. Simulation results showed that with 0.35um CMOS
technology, 80 KHz signal bandwidth and oversampling rate of 64, the modulator achieved 49.25 dB Signal to Noise Ratio (SNR) and
the power consumption was 5.5 mW under ±1.5V supply voltage .
Index terms: Analog-to-Digital conversion, Delta-Sigma modulation, CMOS technology, Transconductance operational
amplifier.
This document discusses the design specifications and considerations for low-noise amplifiers (LNAs), including:
- Noise figure must be low, requiring a transistor with gm exceeding 1/(25 ohms) for a noise figure below 2 dB.
- Gain must be high enough to minimize noise from subsequent mixers while balancing with linearity.
- Input matching is important to achieve a return loss of at least 10 dB and create an input resistance of 50 ohms without noise.
- Stability is crucial as the LNA interfaces with outside signals.
- Linearity is usually not a limiting factor except for CDMA systems.
- Bandwidth must accommodate the full specified frequency band.
- Several common
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive function. Exercise causes chemical changes in the brain that may help protect against mental illness and improve symptoms.
This document provides an overview and specifications for OpenFlow Switch Version 1.5.0, including:
- Descriptions of OpenFlow ports, tables, matching, and processing pipeline
- Details of the OpenFlow channel and control messages for modifying flow tables, groups and meters
- Formats and structures for common OpenFlow objects like ports, matches, actions
[Links vip.net] gap fill reading practiceSĩ Anh Nguyễn
Mosses are small flowerless plants that grow in dense clumps in damp, shady locations. They have simple one-cell thick leaves covering a thin stem that supports them and produces spore-containing capsules. Mosses can grow in many environments like rocks, soil, wood, or bogs, and are sometimes considered weeds in grass but are included in Japanese gardens for their sense of calm and age. Mosses have various uses including decorations, components of peat, and as wound dressings in World War I for their absorption properties.
This document discusses designing a low noise RF amplifier for an 802.11b receiver application using Agilent Technologies' ADS design tools. It presents a step-by-step design process starting with establishing requirements, analyzing transistor stability, performing EM/circuit co-simulation, fabrication, and measurement. Key aspects covered include available gain procedure, noise figure design, stability analysis, constructing available gain and noise circles, and comparing simulated and measured results. The goal is to yield a design that works with the first PCB pass to save costs and time.
This document provides an overview and specifications for OpenFlow Switch Version 1.5.0, including:
- Descriptions of OpenFlow ports, tables, matching, and processing pipeline
- Details of the OpenFlow channel and control messages for modifying flow tables, groups and meters
- Formats and structures for common OpenFlow objects like ports, matches, actions
The document discusses data link layer functions including framing methods, flow control, error control, and protocols. Specifically:
- The data link layer is responsible for reliable transmission of frames over an unreliable physical link. It uses framing, flow control, and error control methods.
- Framing involves organizing bits into frames with defined start and end points. Flow control manages buffer usage to prevent overflow. Error control detects and corrects errors using techniques like ARQ.
- Common data link layer protocols are HDLC and PPP, which use flags, control characters and bit stuffing for framing, and sliding windows or stop-and-wait for flow control. ARQ methods like go-back-N are
Chapter 4 internetworking [compatibility mode]Sĩ Anh Nguyễn
The document provides an overview of network layer concepts including internetworking, IP addressing, routing protocols, and routing algorithms. Some key points include:
- Internetworking allows different networks to connect through protocols like virtual circuits and tunneling.
- IP addresses identify systems on a network and consist of a network portion and host portion. Private IP addresses are used internally.
- Routing protocols like RIP, OSPF, and BGP allow routers to share route information and determine the best path between networks.
- Subnetting divides network classes into smaller subnets to better manage IP addresses and network design.
This document provides an overview of physical layer and network media. It discusses digital communication features and advantages, including error correction. It describes frequency allocations by international standards bodies and different network media such as copper cable specifications, fiber optics, and wireless networks. Key points covered include data transmission speeds, signal attenuation over distance, and common cable types for digital networks.
Programming Foundation Models with DSPy - Meetup SlidesZilliz
Prompting language models is hard, while programming language models is easy. In this talk, I will discuss the state-of-the-art framework DSPy for programming foundation models with its powerful optimizers and runtime constraint system.
HCL Notes und Domino Lizenzkostenreduzierung in der Welt von DLAUpanagenda
Webinar Recording: https://www.panagenda.com/webinars/hcl-notes-und-domino-lizenzkostenreduzierung-in-der-welt-von-dlau/
DLAU und die Lizenzen nach dem CCB- und CCX-Modell sind für viele in der HCL-Community seit letztem Jahr ein heißes Thema. Als Notes- oder Domino-Kunde haben Sie vielleicht mit unerwartet hohen Benutzerzahlen und Lizenzgebühren zu kämpfen. Sie fragen sich vielleicht, wie diese neue Art der Lizenzierung funktioniert und welchen Nutzen sie Ihnen bringt. Vor allem wollen Sie sicherlich Ihr Budget einhalten und Kosten sparen, wo immer möglich. Das verstehen wir und wir möchten Ihnen dabei helfen!
Wir erklären Ihnen, wie Sie häufige Konfigurationsprobleme lösen können, die dazu führen können, dass mehr Benutzer gezählt werden als nötig, und wie Sie überflüssige oder ungenutzte Konten identifizieren und entfernen können, um Geld zu sparen. Es gibt auch einige Ansätze, die zu unnötigen Ausgaben führen können, z. B. wenn ein Personendokument anstelle eines Mail-Ins für geteilte Mailboxen verwendet wird. Wir zeigen Ihnen solche Fälle und deren Lösungen. Und natürlich erklären wir Ihnen das neue Lizenzmodell.
Nehmen Sie an diesem Webinar teil, bei dem HCL-Ambassador Marc Thomas und Gastredner Franz Walder Ihnen diese neue Welt näherbringen. Es vermittelt Ihnen die Tools und das Know-how, um den Überblick zu bewahren. Sie werden in der Lage sein, Ihre Kosten durch eine optimierte Domino-Konfiguration zu reduzieren und auch in Zukunft gering zu halten.
Diese Themen werden behandelt
- Reduzierung der Lizenzkosten durch Auffinden und Beheben von Fehlkonfigurationen und überflüssigen Konten
- Wie funktionieren CCB- und CCX-Lizenzen wirklich?
- Verstehen des DLAU-Tools und wie man es am besten nutzt
- Tipps für häufige Problembereiche, wie z. B. Team-Postfächer, Funktions-/Testbenutzer usw.
- Praxisbeispiele und Best Practices zum sofortigen Umsetzen
GraphSummit Singapore | The Future of Agility: Supercharging Digital Transfor...Neo4j
Leonard Jayamohan, Partner & Generative AI Lead, Deloitte
This keynote will reveal how Deloitte leverages Neo4j’s graph power for groundbreaking digital twin solutions, achieving a staggering 100x performance boost. Discover the essential role knowledge graphs play in successful generative AI implementations. Plus, get an exclusive look at an innovative Neo4j + Generative AI solution Deloitte is developing in-house.
Pushing the limits of ePRTC: 100ns holdover for 100 daysAdtran
At WSTS 2024, Alon Stern explored the topic of parametric holdover and explained how recent research findings can be implemented in real-world PNT networks to achieve 100 nanoseconds of accuracy for up to 100 days.
For the full video of this presentation, please visit: https://www.edge-ai-vision.com/2024/06/building-and-scaling-ai-applications-with-the-nx-ai-manager-a-presentation-from-network-optix/
Robin van Emden, Senior Director of Data Science at Network Optix, presents the “Building and Scaling AI Applications with the Nx AI Manager,” tutorial at the May 2024 Embedded Vision Summit.
In this presentation, van Emden covers the basics of scaling edge AI solutions using the Nx tool kit. He emphasizes the process of developing AI models and deploying them globally. He also showcases the conversion of AI models and the creation of effective edge AI pipelines, with a focus on pre-processing, model conversion, selecting the appropriate inference engine for the target hardware and post-processing.
van Emden shows how Nx can simplify the developer’s life and facilitate a rapid transition from concept to production-ready applications.He provides valuable insights into developing scalable and efficient edge AI solutions, with a strong focus on practical implementation.
UiPath Test Automation using UiPath Test Suite series, part 5DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 5. In this session, we will cover CI/CD with devops.
Topics covered:
CI/CD with in UiPath
End-to-end overview of CI/CD pipeline with Azure devops
Speaker:
Lyndsey Byblow, Test Suite Sales Engineer @ UiPath, Inc.
HCL Notes and Domino License Cost Reduction in the World of DLAUpanagenda
Webinar Recording: https://www.panagenda.com/webinars/hcl-notes-and-domino-license-cost-reduction-in-the-world-of-dlau/
The introduction of DLAU and the CCB & CCX licensing model caused quite a stir in the HCL community. As a Notes and Domino customer, you may have faced challenges with unexpected user counts and license costs. You probably have questions on how this new licensing approach works and how to benefit from it. Most importantly, you likely have budget constraints and want to save money where possible. Don’t worry, we can help with all of this!
We’ll show you how to fix common misconfigurations that cause higher-than-expected user counts, and how to identify accounts which you can deactivate to save money. There are also frequent patterns that can cause unnecessary cost, like using a person document instead of a mail-in for shared mailboxes. We’ll provide examples and solutions for those as well. And naturally we’ll explain the new licensing model.
Join HCL Ambassador Marc Thomas in this webinar with a special guest appearance from Franz Walder. It will give you the tools and know-how to stay on top of what is going on with Domino licensing. You will be able lower your cost through an optimized configuration and keep it low going forward.
These topics will be covered
- Reducing license cost by finding and fixing misconfigurations and superfluous accounts
- How do CCB and CCX licenses really work?
- Understanding the DLAU tool and how to best utilize it
- Tips for common problem areas, like team mailboxes, functional/test users, etc
- Practical examples and best practices to implement right away
Observability Concepts EVERY Developer Should Know -- DeveloperWeek Europe.pdfPaige Cruz
Monitoring and observability aren’t traditionally found in software curriculums and many of us cobble this knowledge together from whatever vendor or ecosystem we were first introduced to and whatever is a part of your current company’s observability stack.
While the dev and ops silo continues to crumble….many organizations still relegate monitoring & observability as the purview of ops, infra and SRE teams. This is a mistake - achieving a highly observable system requires collaboration up and down the stack.
I, a former op, would like to extend an invitation to all application developers to join the observability party will share these foundational concepts to build on:
AI 101: An Introduction to the Basics and Impact of Artificial IntelligenceIndexBug
Imagine a world where machines not only perform tasks but also learn, adapt, and make decisions. This is the promise of Artificial Intelligence (AI), a technology that's not just enhancing our lives but revolutionizing entire industries.
Cosa hanno in comune un mattoncino Lego e la backdoor XZ?Speck&Tech
ABSTRACT: A prima vista, un mattoncino Lego e la backdoor XZ potrebbero avere in comune il fatto di essere entrambi blocchi di costruzione, o dipendenze di progetti creativi e software. La realtà è che un mattoncino Lego e il caso della backdoor XZ hanno molto di più di tutto ciò in comune.
Partecipate alla presentazione per immergervi in una storia di interoperabilità, standard e formati aperti, per poi discutere del ruolo importante che i contributori hanno in una comunità open source sostenibile.
BIO: Sostenitrice del software libero e dei formati standard e aperti. È stata un membro attivo dei progetti Fedora e openSUSE e ha co-fondato l'Associazione LibreItalia dove è stata coinvolta in diversi eventi, migrazioni e formazione relativi a LibreOffice. In precedenza ha lavorato a migrazioni e corsi di formazione su LibreOffice per diverse amministrazioni pubbliche e privati. Da gennaio 2020 lavora in SUSE come Software Release Engineer per Uyuni e SUSE Manager e quando non segue la sua passione per i computer e per Geeko coltiva la sua curiosità per l'astronomia (da cui deriva il suo nickname deneb_alpha).
In his public lecture, Christian Timmerer provides insights into the fascinating history of video streaming, starting from its humble beginnings before YouTube to the groundbreaking technologies that now dominate platforms like Netflix and ORF ON. Timmerer also presents provocative contributions of his own that have significantly influenced the industry. He concludes by looking at future challenges and invites the audience to join in a discussion.
Maruthi Prithivirajan, Head of ASEAN & IN Solution Architecture, Neo4j
Get an inside look at the latest Neo4j innovations that enable relationship-driven intelligence at scale. Learn more about the newest cloud integrations and product enhancements that make Neo4j an essential choice for developers building apps with interconnected data and generative AI.
Communications Mining Series - Zero to Hero - Session 1DianaGray10
This session provides introduction to UiPath Communication Mining, importance and platform overview. You will acquire a good understand of the phases in Communication Mining as we go over the platform with you. Topics covered:
• Communication Mining Overview
• Why is it important?
• How can it help today’s business and the benefits
• Phases in Communication Mining
• Demo on Platform overview
• Q/A
How to Get CNIC Information System with Paksim Ga.pptxdanishmna97
Pakdata Cf is a groundbreaking system designed to streamline and facilitate access to CNIC information. This innovative platform leverages advanced technology to provide users with efficient and secure access to their CNIC details.
20240609 QFM020 Irresponsible AI Reading List May 2024
1.vip agilent 3
1. Agilent Technologies
Practical RF Amplifier Design Using the
Available Gain Procedure and the
Advanced Design System EM/Circuit
Co-Simulation Capability
White Paper by Ken Payne
Abstract
This article features a method of designing a low noise RF amplifier for an 802.11b receiver application and contains an Avago ATF54143
PHEMT transistor. ADS design tools are used such that the techniques presented remove much of the guesswork from the design pro-
cess. Design speed and cost along with RF performance are of utmost importance for most RF designs, thus, one of the main objectives
is to yield a design that works with the first PCB pass. If successful, multiple PCB layouts are avoided, which saves design cost and
time. This design procedure is considered successful even if some of the lumped component values have to be adjusted slightly to get
the desired RF performance – as long as the layout does not have to be modified to have a working circuit. It is also considered success-
ful even if the model prediction doesn’t exactly agree with measured results, but the resulting circuit still meets the design criteria and
specifications. The featured amplifier covers a frequency range of 2.4 GHz to 2.48 GHz. The design is illustrated from start to finish, with
construction of a printed circuit board and measurement results.
Introduction
An amplifier circuit consists mainly of a gain device or devices, and input and output matching or coupling networks. The amplifier
should make weak signals larger without adding too much noise or distortion. Ideally, the amplifier would add no noise and would not
distort the signal in any way. Electronic devices are not ideal however, and thus degrade the signal to some degree. The amplifier design
objective is to minimize the noise added and the distortion created while increasing the amplitude of the signal. Design trade-offs allow
one to obtain the best possible performance from a particular active device.
Figure 1
3. 3
where: FT is the total system noise factor,
F1 is the noise factor of stage one,
F2 is the noise factor of stage two,
Fn is the noise factor of stage number n.
g1 is the numeric gain factor of stage one,
g2 is the numeric gain factor of stage two,
gn-1 is the numeric gain factor of the second to the last stage.
Based on Equation 1, earlier gain stages diminish the effect of cumulative noise added
by stages farther back in the system. Thus, trading away too much gain for lower noise
figure in the early stages of the system may degrade the overall system noise due to less
noise “take-over” of the following stages.
Equations 2 and 3, respectively, convert noise figure, NF in dB, to numeric noise factor, F
and gain, G in dB to gain factor, g:
Use Equations 1 through 5 to determine amplifier gain and noise figure requirements for
a given system.
A two-port network is terminated as shown in Figure 2. The generalized transducer
numeric gain equation for the two-port s-parameter block terminated by ΓS
and ΓL
of
Figure 2 is given by Equation 6:
Background For low noise amplifier designs, the available gain design approach is typically utilized to
facilitate a gain versus noise “trade-off”. Most applications do not allow or necessarily
require a minimum noise design since gain is reduced to allow for the lower noise perfor-
mance. Thus, a gain versus noise “trade-off” is appropriate. Knowledge about the system
in which the amplifier is to be used is required to make the appropriate gain versus noise
trade-off. If subsequent stages following the RF amplifier have a high cumulative noise
figure, more gain is required to “take-over” the noise figure of those stages, thus provid-
ing the lowest possible system noise. An example system is shown in Figure 1. System
noise factor is calculated using the Friis formula as follows:
Background
Transducer Gain
FT = F1 + + + . . . +
F2 – 1 F3 – 1 Fn – 1
g1 g1 g2 g1 g2
. . . gn–1
Equation 1.
NF = 10logF G = 10log(g)Equation 4. Equation 5.
gT =
|S21|2
(1–|ΓS|2
)(1– ΓL|2
)
|(1–S11ΓS)(1–S22ΓL)– S21 S12 ΓS |ΓL|
Equation 6.
F= 10
NF
10
g= 10
G
10Equation 2. Equation 3.
Equations 4 and 5 respectively, convert noise factor, F to noise figure, NF in dB, and gain
factor, g to gain, G in dB:
4. 4
1–|S11|2
–|S22|2
+|∆|2
2|S12 S21|
≥1K =
|∆|=|S11 S22 – S21 S12|< 1
B1
=1+|S11 |2
– |S22|2
–|∆|2
> 0
B2
=1+|S22|2
– |S11|2
–|∆|2
> 0
ΓS ΓLΓIN ΓOUT
ΓS ΓL
[S]
The s-parameters describe a device for a particular set of conditions, such as frequency,
bias, and temperature as shown in Equation 6. Transducer gain, gT
, is a function of the
s-parameters, ΓS
, and ΓL
. Convert numeric transducer gain gT
, to gain GT
in dB by use of
Equation 5. When the device is terminated in the same impedance as when s-parameters
were measured, ΓS
and ΓL
are zero and gT
= |S21
|2
.
The Figure 2 two-port network may be stable or potentially unstable. It is imperative that
the amplifier does not oscillate in the product environment, since such behavior leads to
product malfunction. If the two-port is potentially unstable, there are conditions where
oscillations can occur. Certain source or load terminations that produce the oscillations
provide the conditions necessary for the unstable behavior. This type of design is called a
conditionally stable design. If the conditionally stable design method is utilized, extreme
care must be observed to guarantee that a source or load termination that produces an
oscillation is never presented to the amplifier. This applies to all frequencies in-band and
out-of-band. This can be a difficult task at best in most applications. The unconditionally
stable design approach allows any source or load terminations, which have reflection
coefficient magnitudes between 0 and 1, inclusive, presented to the amplifier without
the possibility of an oscillation. It is highly recommended that the two-port is made
unconditionally stable at all frequencies. An unconditionally stable design guards against
unexpected oscillations, which cause product malfunction.
Two-port stability is analyzed using stability circles or equations. In this design
example, stability equations are used to achieve an unconditionally stable design at all
frequencies. The stability equations are a function of the Figure 2 two-port s-parameters.
Equation 7 gives the value for stability factor K, which is made greater than or equal to
unity for stability. Additionally, stability factors ∆, B1, and B2 are shown by Equations
8, 9, and 10 respectively. To achieve unconditional stability, the two-port must satisfy
Equation 7 and either Equation 8, 9, or 10. If Equation 8, 9, or 10 is satisfied, all three
equations are, by definition, satisfied. Thus, if K ≥ 1, the two-port network may not be
unconditionally stable. Having K ≥ 1 is a necessary, but not sufficient, condition for
unconditional stability. Additionally, Equation 8, 9, or 10 is analyzed to determine if the
two-port network stability is unconditional. Thus, |∆| < 1, or B1 > 0, or B2 > 0 must also
be met along with K ≥ 1 to guarantee unconditional stability.
Figure 2.
Stability Analysis
Equation 7.
Equation 8.
Equation 9.
Equation 10.
5. 5
1–|S11|2
|S22 – ∆ (S*11)|+|S21 S12|
≥1μSource =
1–|S22|2
|S11 – ∆ (S*22)|+|S21 S12|
≥1μLoad =
ΓOUT = S22+
S21S12ΓS
1–S11ΓS
gT =
1–|ΓS|2
1–|ΓL|2
|1–S11ΓS|2
|1–ΓOUT ΓL|2|S21|2
Alternately, the single test stability factor μSource
or μLoad
is calculated using Equation 11
or Equation 12. If μSource
≥ 1 then μLoad
≥ 1 by definition and vice versa. If Equation 7 is
satisfied and either of Equations 8, 9, or 10 are satisfied, then both Equations 11 and 12
are satisfied. And, of course, if Equations 11 or 12 are satisfied, then Equations 7 through
10 are satisfied.
If the two-port network is not unconditionally stable, and unconditional stability is
required, stabilizing networks are added. Methods of stabilizing the two-port include
feedback. These methods typically degrade some parameter such as maximum gain
or noise figure. If care is taken, minimal degradation is possible while achieving
unconditional stability. Once the stability networks are added, they become part of the
two-port network and new s-parameters that describe the new two-port network are
calculated. These new s-parameters are used in the stability equations to verify stability.
Once the two-port network is unconditionally stable, input and/or output matching
networks are added to get the desired performance.
For low noise amplifier design, the available gain design approach is typically performed.
When performing the available gain design procedure, the source termination is
constrained to some arbitrary impedance (usually for better noise performance), and
the resulting output reflection coefficient of the device is conjugately matched. Thus, a
mismatch may exist at the input whereas the output is perfectly matched. If a mismatch
exists at the device input, the amount of gain is less than the maximum possible gain
as is the case when both input and output are conjugately matched. To determine the
amount of available gain with the input mismatched, Equation 6 is modified. Since the
output is conjugately matched for a given source termination, ΓOUT
is expressed in terms
of ΓS
and the two-port s-parameters. By substitution and rearrangement, this also allows
Equation 6 to be expressed in terms of ΓS and the two-port s-parameters. The available
gain design procedure is applicable to both the conditionally stable and unconditionally
stable cases. This amplifier design procedure examines the unconditionally stable case
only.
The transducer gain equation gT
of Equation 6, is rearranged as shown in
Equations 13 and 14:
Available Gain Design
Procedure
Equation 11.
Equation 12.
Equation 13.
Equation 14.
where:
6. 6
Substituting Equation 14 into Equation 15 yields the available gain equation, gA
, as shown
in Equation 16, which is a function of ΓS
and the two-port s-parameters.
gA =
1–|ΓS|2
1
|1–S11ΓS|2
1–|ΓOUT|2|S21|2
Equation 15.
gA =
|S21|2
(1–|ΓS|2
)
S22 – ∆ΓS
1– S11ΓS
1– |1– S11ΓS|2
( (
2
Equation 16.
Equation 21 describes transistor noise factor performance. As shown in this equation,
transistor noise performance is independent of load termination and is determined solely
by its source termination and noise parameters. The noise parameters fully describe the
noise performance of a device for a specific set of conditions such as frequency, bias,
and temperature.
F= FMin
+
4rn|ΓS – Γopt|2
(1–|ΓS|2
)|1 + Γopt|2Equation 21.
Noise Figure Design
Procedure
When the device output is conjugately matched for a given source termination ΓS
,
then transducer gain, gT
, is simplified in terms of the s-parameters and ΓS
. Conjugately
matching the output mathematically yields ΓL
= ΓOUT
* and Equation 15 yields available
gain, gA
:
A family of circles known as available gain circles are constructed that provide a
specific amount of mismatch at the device input. An infinite number of source
terminations forming the circle allow selection of mismatch at the device input. To
construct an available gain circle, locate the center of the circle on a Smith chart and
draw the circumference from a calculated radius. Locate the center for a particular gain
circle using Equation 20, which yields a magnitude and angle. The desired available gain
in dB is converted to numeric gain factor gA
for Equation 17. Equation 17 is then used in
Equations 19 and 20.
ga =
gA
|S21|2
Equation 17.
C1
= S11 – ∆S*22
Equation 18.
Ra =
[1– 2K|S12 S21|ga
+|S12 S21|2
g2
a]½
1 + ga(|S11|2
– |∆|2
)
Equation 19.
Plotting available gain circles in conjunction with noise contours allows an easy
selection of gain versus noise figure for the amplifier.
Ca =
ga
C1
*
1 + ga(|S11|2
– |∆|2
)
Equation 20.
The radius of an available gain circle is calculated by equation 19:
Transistor noise factor F is a function of ΓS
, FMin
, rn
, and Γopt
, where FMin
, rn
, and Γopt
are known
as the transistor noise parameters. ΓS
terminates the two-port input of Figure 2. As ΓS
approaches Γopt
, the transistor noise factor approaches its minimum. As ΓS
departs from
Γopt
, the noise factor increases from its minimum value. The rate at which the noise factor
increases depends on the noise resistance rn
. Conversion of transistor noise factor to noise
figure in dB is obtained from Equation 4. Equation 22 obtains the noise resistance rn if FMin
,
Γopt
, and the noise factor with the input terminated in 50 Ω is known. (ΓS
= 0)
7. 7
Since noise factor degrades as the source termination departs from Γopt
, contours may
be constructed which yield a given noise performance for a particular source termination
called noise circles. An infinite number of source terminations forming a circle provide a
given noise figure. The noise circles are plotted by first locating the center of a particular
circle using Equation 24.
rn = (FΓs=0 – Fmin
)
|1+Γopt|2
4|Γopt|2
Equation 22.
Equation 25 calculates the radius of each noise circle.
Ni
=
Fi
– Fmin
4rn
|1+Γopt|2
Equation 23.
CFi
=
Γopt
1+ Ni
Equation 24.
For low noise amplifier design, a gain versus noise trade-off is typically made.
Available gain circles are plotted with constant noise figure circles for a trade-off
between gain and noise figure. The optimum noise performance seldom coincides with
the maximum gain of the device. Since each gain or noise circle describes the device
performance under a given set of conditions, a prediction of gain and noise figure is
determined by a known source termination. Enhanced noise performance is obtained with
a source termination closer to the optimum noise termination Γopt
, at the expense of gain.
More gain results when the source termination is conjugately matched to the device
input, ΓMS
, at the expense of noise figure. A trade-off is made between noise and gain by
selecting an intermediate source termination. Thus, neither optimum noise nor maximum
gain is obtained.
RFi
=
1
1+ Ni
√ N2
i +Ni
(1–|Γopt|2
)Equation 25.
A low noise amplifier (LNA) is required for a WCS (wireless communication system)
receiver application. Using Equations 1 through 5 and system specifications, it is
determined that the LNA requires the following performance:
802.11b Amplifier
Design Requirements
Frequency range:...................................... 2.4 GHz to 2.48 GHz
Gain: .......................................................... > 12 dB
Noise figure: ............................................ < 2.5 dB
Input return loss....................................... > 10 dB
Output return loss ................................... > 10 dB
Third order input intercept point:.......... > 0 dBm
Supply voltage: ........................................ 3.3 Volts
Supply current: ......................................... < 100 mA
Several manufacturers produce high performance transistors that are suitable for this
particular design. Frequency range, maximum gain, minimum noise figure, and linearity
are all considered during the active device selection process. One aspect that is often
overlooked during the selection process is whether or not measured s-parameters, noise
parameters, and a nonlinear model exist for the chosen transistor. Design cycle times are
significantly reduced if nonlinear models and measured s-parameter and noise parameter
data is available from the manufacturer. Having the data in electronic form speeds import
into the chosen RF/μWave
circuit simulator. It is highly recommended that supplied data
is verified in a measurement lab if available to ensure its validity before too many design
resources are committed to a particular device.
8. 8
Figure 3. ATF54143model.dsn
Since both the nonlinear model and measured s-parameters are available, a quick
validation is possible and recommended. Avago measured s-parameter data with a
3.0 Volt bias voltage at the drain and a drain-to-source current of 60 mA. Figure 4 shows
an s-parameter simulation that plots the Avago measured s-parameter. An Amplifier
Design Guide (from a schematic, select: DesignGuides > Amplifier > S-Parameter
Simulations > S-Params., Noise Fig., Gain, Stability, Circles, and Group Delay) is used to
quickly set up the simulation as shown in Figure 4. The ATF541433_3V60mA.s2p file has
both s-parameters and noise data included. The simulation is performed from 100 MHz to
6 GHz, stepped every 10 MHz and stored in a dataset. These results are later compared to
the nonlinear model s-parameter simulation.
Several transistors were selected as candidates for the WCS LNA by inspection of
corresponding data sheets. Many devices were quickly eliminated since a nonlinear
model and measured s-parameters were not available from the particular manufacturer
in electronic form. The Avago ATF54143 has measured s-parameter and noise parameter
data at various bias conditions and a nonlinear model available in electronic form and
specifications that should yield a design with the desired performance. The ATF54143
nonlinear model available from Avago is shown in Figure 3.
Transistor S-Parameters
and Nonlinear Model
Latest ATF-54143curtice ADS MODEL
9. 9
S-Parameters, Noise Figure, Gain, Stability,
Circles, and Group Delay versus Frequency
enhancement mode FET that requires a positive gate voltage with respect to its source
to obtain the desired drain-to-source bias current of 60 mA. A voltage divider network
is provided by Ra and Rb and is adjusted in the simulator to quickly obtain the required
60 mA drain-to-source current. Standard resistor values are used. Ra is arbitrarily set
to 33 kΩ. Next, Rb is manually adjusted by entering standard resistor values to yield
the desired bias current as shown in Figure 5. Note that Rg, the 10 kΩ resistor is not
necessary for transistor DC bias, but acts as an “all-frequency” choke to effectively
isolate the gate from the bias network “RF-wise”. This will be important when the RF
aspects of the design are accomplished. Nearly any resistor value is acceptable from a
DC bias standpoint since no DC current flows through this resistor. Larger resistor values
provide better RF isolation than smaller ones. A smaller resistor can be used in this
position if it is determined that the transistor is unstable and requires parallel loading
at the input to achieve stability. Adding a bypass capacitor to ground at the Ra, Rb, and
Rg junction effectively AC grounds Rg. For now, the 10 kΩ resistor is used for the DC
simulations and preliminary RF simulations.
Figure 4. ATF54143_Avago_S-parameters.dsn
Now, the nonlinear model is biased at the same DC operating point as was the
device for the measured s-parameter data provided by Avago as shown in Figure 5. The
target product has a 3.3 V regulated supply voltage available for biasing the amplifier.
The ATF54143 nonlinear model sub-circuit is shown as a symbol (sub-circuit) and
labeled “Latest_ATF54143”. The ATF54143 nonlinear model has the 3.3 V supply voltage
connected to the drain through a 5 Ω resistor Rd. This resistor drops the supply voltage
from 3.3 V to 3.0 V when 60 mA of bias current flows through the drain terminal. The
transistor s-parameters are affected very little when the drain voltage is 3.3 V instead
of 3.0 V. However, adding the resistor will make the application conditions more
closely resemble conditions for the Avago measured device s-parameters. It could
also slightly limit a short circuit condition at the transistor drain when the bias choke
coil is at its self-resonant frequency. Figure 5 shows a DC choke coil, “DC_Feed” that
is later replaced with an inductor in the built-up circuit. Note that the ATF54143 is an
10. 10
freq Idrain.i Vd
0.0000 Hz 61.38 mA 2.993 V
Figure 5. DCbias.dsn
Figure 6 shows the DC simulation results with Ra set to 33 kΩ and Rb set to 6.8 kΩ. Note
that the drain bias current is nearly 60 mA (61.38mA) and the drain voltage is nearly
3 Volt (2.993V). This is close enough to the target bias values.
An s-parameter simulation is now possible on the biased nonlinear model. DC
blocking capacitors and 50 Ω terminations are added to the circuit input and output
of Figure 5 to obtain the circuit shown in Figure 7. S-parameter simulations are now
Figure 6. DCbias.dds
obtained from 100 MHz to 6 GHz with a frequency step of 10MHz. (The Avago ATF54143
datasheet indicates that device s-parameters were measured on a 20 mil thick PCB
and recommends connecting two vias in parallel with each other on each source to
ground. This was added to the Figure 7 circuit and found to have a minimal effect. The
nonlinear model simulated s-parameter data without the ground vias closely matches
measured s-parameter data. Thus, the PCB ground vias are not added as indicated in
the datasheet.) Figure 8 plots nonlinear model simulated s-parameters and the Avago
measured s-parameter data. Note the close similarity between the two s-parameter data
sets.
Figure 7. S-parametersModel.dsn
11. 11
Figure 8. ATF54143_MeasVsModel_S-parameters.dds
S-Parameter Data
Validation
It is beneficial to validate data obtained from any vendor if a measurement lab is
available. In this case, s-parameter data is measured with an Intercontinental Microwave
(ICM) transistor test fixture. The ICM transistor test fixture is used with the appropriate
midsection and ICM TOSL-3001 calibration kit. Before calibration is performed, all
TOSL-3001 calibration coefficients are loaded into the network analyzer. Each calibration
standard has a unique set of coefficients that describe it’s RF response. The ICM
calibration coefficients used to describe the TOSL-3001 calibration kit are shown in
Tables 1 and 2. The upper frequency limit for the ICM calibration kit is 6 GHz. Once the
ICM calibration coefficients are loaded into the network analyzer, the TOSL calibration for
the transistor test fixture is possible.
Figure 9 shows the measurement setup used to measure ATF54143 s-parameter data.
The HP4142B DC Source/Monitor is connected to the E8364B network analyzer bias tees
located on the back of that instrument. The HP4142B will supply 3.0 Volts to the Port 2
bias tee and will supply a voltage between 0 V and 1 V at the Port 1 bias tee. The current
sourced from the HP4142B is limited to 100 mA to ensure that the 500 mA bias tee fuses
are not accidentally blown. The HP4142B DC Source/Monitor should be disconnected or
turned off during calibration to avoid blowing the port bias fuses in the network analyzer
as an added safety precaution. The E8364B network analyzer source power is set to
–25 dBm to ensure the measured device is not driven into compression during
measurement. The network analyzer IF bandwidth is set to 300 Hz to limit noise and
increase the dynamic range of the measurement system. The TOSL calibration is now
performed using the ICM TOSL-3001 calibration kit.
12. 12
CLASS A B C D E F G Standard Class Label
S11
A 2
S11
B 1
S11
C 3
S11
A 2
S11
B 1
S11
C 3
Forward Transmission 4
Reverse Transmission 4
Forward Match 4
Reverse Match 4
Response 1 2 4
Response & Isolation 1 2 4
TRL Thru
TRL Reflect
TRL Line
Adapter
TRL Option
Cal Z0: _____ System Z0 _____ Line Z0
Set Ref: _____ Thru _____ Reflect
Standard Class Assignments Calibration Kit: ICM TOSL-3001
Calibration kit: 1CM TOSL-3001
STANDARD
C0
10-15
F
C1
10-27
F/Hz
C2
10-36
F/Hz2
C3
10-45
F/Hz3 Fixed or
Sliding
Terminal
Impedance
Ω
Offset
Frequency
(GHz) Coax or
Waveguide
Standard
Label
# TYPE
L0
10-12
H
L1
10-24
H/Hz
L2
10-33
H/Hz2
L3
10-42
H/Hz3
Delay
pSec
Z0
Ω
Loss
GΩ /s
MIN MAX
1 SHORT 0 0.49 154.8 0 0 6.1 COAX SHORT
2 OPEN 37.7 4860 -5000 560 0 50 0 0 6.1 COAX OPEN
3 LOAD FIXED 1.485 120.9 0 0 6.1 COAX LOAD
4 THRU 0 50 0 0 COAX THRU
5
Table 2.
Figure 9. Transistor s-parameter measurement setup
Table 1.
13. 13
S-Parameters, Noise Figure, Gain, Stability,
Circles, and Group Delay versus Frequency
Once calibration is completed and verified, the HP4142B DC Source/Monitor is
reconnected or turned back on as shown in Figure 9. Using the HP4142B is a very
accurate way of setting/monitoring voltages and currents. First, the 3 Volt DC bias
is supplied to Port 2 on the network analyzer through the Port 2 bias tee to bias the
transistor drain terminal. The HP4142B DC Source/Monitor compliance is set to 100 mA
so as to limit current into the bias tees. The desired bias current into Port 2 is 60 mA,
thus the compliance (current limit) is set to 100 mA. Essentially, no current is needed
to bias the gate of the FET connected to Port 1, so the compliance is set to 10 mA. The
bias voltage on Port 1, which is connected to the transistor gate through the bias tee,
is set to 0.5 Volt. Drain current is now measured with the HP4142B DC Source/Monitor
and found to be slightly below 60 mA. The Port 1 (gate) voltage is slowly increased until
60 mA is measured with the HP4142B DC Source/Monitor going into Port 2 – the drain
terminal. Once the drain-to-source current is set to 60 mA with the drain voltage at
3.0 V, the s-parameters are now measured and saved to a Touchstone file. Figure 10 uses
an Amplifier Design Guide to plot the lab-measured s-parameters with the simulator.
Figure 10. ATF54143_ICM_S-parameters.dsn
14. 14
Figure 11. ATF54143_ALL3_S-parameters.dds
A comparison is now made between the Avago measured s-parameters, the nonlinear
model generated s-parameters, and the lab measured s-parameters. Figure 11 plots
all s-parameter results and shows that all are in close agreement with each other.
Since measured data and modeled data are consistent with each other, any of these
can be used to proceed with the linear design. Of course, third order intermodulation
distortion and gain compression require the nonlinear model for simulation purposes.
Noise figure simulation requires linear noise parameters. Noise parameters are included
in the s-parameter Touchstone file ATF541433_3V60mA.s2p provided by Avago. This
s-parameter data file also has data up to 18GHz where as the ICM data is only measured
to 6 GHz due to the calibration kit frequency limitation. Stability should be considered for
all frequencies or at least with data covering as much frequency range as possible. Thus,
the Avago measured data is used to simulate stability, available gain, and noise figure.
A preliminary stability analysis is performed using an Amplifier Design Guide
and the Avago measured s-parameter data as shown in Figure 12. Note that the stability
analysis is performed from 100 MHz to 18 GHz – the entire range of the data file.
ATF54143 Stability
15. 15
S-Parameters, Noise Figure, Gain, Stability,
Circles, and Group Delay versus Frequency
Figure 12. ATF54143_StabilityAnalysis.dsn
It is highly recommended that the amplifier circuit is made unconditionally stable at all
frequencies to ensure that it does not produce unwanted oscillations. If the amplifier
should happen to oscillate while being used in it’s product environment, it may cause
product malfunction. It can be very difficult to determine the root cause of product
malfunction due to oscillating amplifiers. To achieve unconditional stability, Equations
7 through 10, show that K ≥ 1 and {|∆|< 1 or B1 > 0 or B2 > 0}; or separately Equation
11 or Equation 12 geometric stability factors μsource
≥ 1 or μload
≥ 1. The ADS Amplifier
Design Guide calculates and displays Equations 7, 11, and 12. Note that satisfying K
≥ 1 does not indicate or guarantee unconditional stability. If either μsource
≥ 1 or μload
≥
1 then the amplifier circuit is guaranteed to be unconditionally stable. If the equations
indicate unconditional stability, it means that the amplifier will not oscillate when its
input and output are terminated with impedances having zero or positive resistances. In
other words, as long as the input and output are terminated with reflection coefficient
magnitudes between 0 and 1, inclusive, the circuit will not oscillate. If feedback through
inductive coupling is introduced or modified, by putting the amplifier in a metal housing,
the amplifier may still oscillate. Environmental conditions, such as temperature, can
also produce unwanted oscillations. A change in temperature changes the active device
s-parameters. To ensure unconditional stability, s-parameters should be taken under all
extreme conditions and a stability analysis performed. One other way to ensure stability
as far as environmental conditions are concerned is to provide significant margin to the
stability conditions. In other words, make K >> 1 at all frequencies if possible.
16. 16
Figure 13. ATF54143_StabilityAnalysis data display. Insert from schematic menu pick
DesignGuide > Amplifier > S-Parameter Simulations > S-Params., Noise Fig., Gain,
Stability, Circles, and Group Delay.
Figure 13 shows the Figure 12 analysis results. This plot was set up using one of
the data display Amplifier Design Guides that correspond to the Stability Analysis
Amplifier Design Guide used to set up the simulation. The Amplifier Design Guide plots K,
μsource
, and μload
(Equations 7, 11, and 12) as shown in the red box. Note that the Amplifier
Design Guide plots stability factor K, which, on its own, is necessary, but not sufficient to
guarantee unconditional stability. Either |∆|, B1, or B2 also have to be plotted to use K
as the stability indicator. Satisfying either μsource
≥ 1 or μload
≥ 1 guarantees unconditional
stability. Observation of the Stability Factor K, geometric stability factors μsource
and μload
all indicate potential instability below 4 GHz and marginal unconditional stability above 4
GHz. (Marginal unconditional stability above 4 GHz can only be assessed with μsource
and
μload
since K alone does not indicate unconditional stability.) Above 8 GHz, the data looks
questionable since the K, μsource
, and μload
plots have an up-and-down variation associated
with them. Since the amplifier is used well below 8 GHz, this variation will be ignored to
some degree. It is highly recommended that the amplifier is unconditionally stable at all
frequencies to ensure that the circuit does not produce unwanted oscillations in or out
of the operating frequency band. Thus, it is important to stabilize this device and ensure
that unconditional stability exists at all frequencies. At frequencies above 8 GHz where
variation in K, μsource
, and μload
are noticed, a stabilizing network that provides significant
stability margin is employed so that data inaccuracies can be ignored. Also note, that this
is a preliminary stability analysis. If it is not possible to stabilize the ideal circuit without
layout and component parasitics and still meet design objectives, it may not be possible
to stabilize the device once it is placed in a physical layout. Therefore, an attempt is
made to stabilize the device without parasitics. If the device is stabilized and still meets
all the performance criteria, then parasitics are added. A new stability analysis is then
performed. If the circuit is again unstable, attempts are made to stabilize the device with
parasitics. Once the circuit is stable, it is checked to ensure that it still meets its design
objectives.
Transistors are stabilized through the use of series and parallel feedback and
series and parallel loading at the input and output. A combination of these networks
may be necessary to get the desired stability results. Stabilizing network selection and
approach depends on the type of device(s) used, the amplifier configuration, and design
performance objectives. A common source FET amplifier has a relatively high input
reflection coefficient and typically requires input loading to achieve stability. In a low
noise amplifier application, however, resistive loss added to the amplifier input degrades
noise figure and should be avoided if possible.
17. 17
An ADS Amplifier Design Guide that stabilizes an unstable circuit is used to stabilize the
transistor circuit as shown in Figure 14 (From a schematic, select DesignGuide > Amplifier
> S-Parameter Simulations > Feedback Network Optimization to Attain Stability). The ADS
default Amplifier Design Guide has parallel feedback and parallel loading at the input and
output. Unconditional stability is desired at all frequencies, thus, the Amplifier Design Guide
default stabilizing networks are modified. Series loading (R1) is added at the output, the
inductor in the feedback path is removed, and the capacitors CFB and COUT are changed
to DC blocking capacitors by setting them to 1uF. Since this amplifier is used in a low
noise application, it is desirable to limit loss at the device input, which degrades amplifier
noise figure. Thus, capacitor CIN is changed to 0.5 pF to limit input loading at the operating
frequency since loss added at the input degrades noise figure. The 0.5 pF capacitor has
a relatively high reactance at 2.5 GHz and this reactance decreases with an increase in
frequency. This allows input parallel loading at higher frequencies and very little loading
at 2.5 GHz. This type of loading can be thought of as frequency selective loading. The CIN
capacitor is also renamed to C1 such that it is not altered during the optimization process.
Input series loading also degrades noise figure. Series loading could be frequency selective
as well by putting an inductor in parallel with the load resistor, but inductors typically have
higher parasitics than do capacitors, thus input series loading will not be considered in
this design. Resistive feedback can also degrade noise figure. In this particular case, the
resistive feedback helps stabilize the circuit at low frequencies and has little impact at the
operating frequency.
Figure 14. ATF54143_StabilityOpt.dsn
The optimization goals are set to optimize for stability, maximum gain, and minimum
noise figure. The stability goals OptimGoal1 and OptimGoal2 are set to a Min = 1.05 as
a default over the entire simulation frequency range. These goals ensure that μsource
≥ 1
and μload
≥ 1, which indicates unconditional stability. Note that if either μsource
≥ 1 or μload
≥
1 then the other is, by definition, greater than unity. OptimGoal3 is set to a Min = 14 dB
for dB(S21) over the 2.4 GHz to 2.5 GHz operating frequency range. Noise figure is set to
a Max = 1.5 dB over the same operating frequency range. The starting values for each
of the stabilizing components in the optimization are arbitrarily chosen as Rfb
= 680 Ω, Rin
= 50 Ω, RSout
= 10 Ω, and Rout
= 500 Ω. The optimization simulation is now executed and
the results are shown in Figure 15. The optimized resistance values shown in the figure
indicate that Rfb
= 547.4 Ω, Rin
= 278.7 Ω, RSout
= 6.1 Ω, and Rout
= 216 Ω and unconditional
stability is achieved from 100 MHz to 18 GHz. Also note that at 2.5 GHz gain is 14.17
dB, which exceeds the design target of 12 dB. The minimum noise figure in the plot at
2.5 GHz is 1.03 dB as indicated. The minimum noise figure is not necessarily the noise
figure of the circuit as indicated by Equation 21, but depends on how the device input is
terminated. Note that the desired 2.5 dB noise figure is possible with this circuit.
18. 18
Figure 15. ATF54143_StabilityOpt.dds
Component and layout parasitics are not included in the design yet. Typically, if the
preliminary analysis does not meet the design criteria, the final actual circuit with
parasitics will not meet the objectives. In other words, parasitics typically degrade RF
performance. In this case, the preliminary analysis indicates the transistor and amplifier
topology chosen may indeed yield a design that meets all design objectives. Next,
some of the component parasitics and preliminary layout parasitics are considered to
determine what affects they may have on circuit performance.
Component parasitics include loss and unexpected reactance. Inductors have
losses and parasitic capacitance whereas capacitors have loss and parasitic inductance.
For this design, an inductor is needed to feed DC bias into the FET drain terminal.
Figures 5 and 7 show an ideal DC feed (choke) to inject bias current into the FET drain.
A Coilcraft Midi series air-wound inductor replaces the ideal DC feed. The inductor is
needed merely to feed DC bias current to the FET drain. Ideally, a very large inductance
is needed for the DC feed coil. Inductor parasitic capacitance limits the allowable
inductance value due to self-resonance. A 27 nH Coil Craft Midi series inductor has a
minimum self-resonance frequency of 2.7 GHz. This gives the highest possible inductive
reactance at the 2.5 GHz operating frequency while the inductor self-resonant frequency
is still above the amplifier operating frequency.
Figure 16. CC1812SMS.dsn
19. 19
Figure 16 shows an equivalent circuit model of the Midi series air-wound inductor
supplied by CoilCraft with part number 1812SMS-27N. Notice the transmission line TL1
in the model. Using a transmission line in this model causes the model to diverge from
actual inductor performance at frequencies above self-resonance due to the nature of
transmission lines. A subcircuit (CC1812SMS) is now created with the 27 nH inductor
lumped equivalent circuit for use in the amplifier circuit.
Figure 17. ATF54143amp1_1pH.dsn
The stabilized circuit is now updated with standard resistor values and the 27 nH
bias choke coil subcircuit from Figure 16 as shown in Figure 17. The parallel input load
resistor R1 is optimized to 278.7 Ω. A 240 Ω standard value resistor is used for the
parallel input load. The output parallel load resistor R2 optimized to 216 Ω. A 220 Ω
standard value resistor is used for the output parallel load. The series output load R3
optimized to 6.1 Ω. A 10 Ω standard value resistor is used for the series output load. The
feedback resistor R4 optimized to 547.4 Ω. A 620 Ω standard value resistor is used for
the feedback resistor as shown. Figure 5 shows that the 3.3V bias is first fed through
a 5 Ω resistor R5 before being fed into the choke coil to drop the drain bias from the
3.3 V battery voltage to 3.0 V. Note in Figure 17 that the “cold” end of the 27 nH inductor
is connected in series with this 5 Ω resistor. The 3.3 V battery is not needed for the
s-parameter analysis, but the effects of the bias choke (27 nH inductor) is included in the
RF simulation. The bias choke and 5 Ω resistor series combination is bypassed with the
0.1 μF capacitor, C2, as shown in Figure 17. The battery is connected to the 5 Ω resistor
and 0.1 μF capacitor junction in the final circuit. Thus, this node is grounded “RF-wise”
due to C2.
Layout parasitics that can wreak havoc on RF circuit performance include ground or lead
inductance and parasitic capacitance on the signal path. Minute amounts of ground or
lead inductance can cause a calculated unconditionally stable circuit to be unstable.
Ground inductance can also cause actual measured circuit gain to be significantly
dissimilar to gain predicted with ideal s-parameter simulations. Resistive loading or
feedback is used to stabilize a transistor as discussed earlier. Parasitic inductance in the
ground or layout traces can effectively isolate such stabilizing circuits from the active
device. Parasitic ground inductance in a transistor source or emitter circuit is a form
of reactive series feedback that can cause unwanted oscillations. The circuit in Figure
17 includes parasitic ground inductance at the FET source terminal represented by the
lumped inductor L1. At this point in the design process, it is helpful to find out how
sensitive the circuit may be to this unavoidable parasitic ground inductance. The circuit
in Figure 17 has virtually no parasitic ground inductance since the L1 inductance value
is set to 1 pH, but the inductor is inserted for the analysis. Later, this inductance will be
increased to determine what effects it has on final circuit performance.
20. 20
Figure 18 shows an s-parameter plot from the Figure 17 analysis. Both |S11| and |S22|
are inside the unit radius Smith chart, which is a necessary, but not sufficient condition
for unconditional stability. The dB(S21) plot shows the 50 Ω gain of 13.82 dB at 2.5 GHz
which is slightly lower than the 14.17 dB of gain predicted by Figures 14 and 15. The
lower gain is partly due to the resistor values being changed to standard value resistors
and the additional loss added by the 27 nH bias tee choke inductor.
A stability analysis could be performed on this circuit since the |S11| and |S22| are
inside the unit radius Smith chart, but a study of ground inductance effects on circuit
performance is now desirable. As mentioned earlier, the lumped inductor L1 in Figure
17 is added to represent parasitic ground inductance. An arbitrary value of 1nH is now
used to get an indication on how sensitive the circuit is to parasitic ground inductance.
The 1 nH inductance value is very small. Higher values of ground inductance are not
uncommon in PCB layouts. Figure 19 shows the L1 parasitic ground inductor from Figure
17 is changed to 1nH. Everything else in the circuit remains unchanged. The simulation is
now executed from 10 MHz to 10 GHz.
Figure 18. ATF54143amp1_1pH.dds
21. 21
Figure 19. ATF54143amp1_1nH.dsn
Figure 20 displays the Figure 19 circuit s-parameters. The |S11| is outside the unit radius
Smith chart indicating an input reflection coefficient magnitude greater than unity. This
indicates that small amounts of parasitic ground inductance make this circuit potentially
unstable at some frequencies. Since the input reflection coefficient magnitude is greater
than unity, a stability analysis is not necessary to determine whether or not the amplifier
has a propensity to oscillate. Having the output terminated in 50 Ω already causes the
input reflection coefficient magnitude to become greater than unity, in other words
producing negative resistance – a condition needed for oscillation. The dB(S21) plot
shows that the 50 Ω gain at 2.5 GHz is reduced from 13.82 dB to 7.48 dB. That’s a
6.3 dB gain loss from the circuit without parasitic ground inductance. This simple
analysis indicates how crucial the layout is with respect to the parasitic ground
inductance at the source lead. Every effort is made to minimize layout ground inductance
so the amplifier meets the gain requirement and does not oscillate in the application.
The analysis also indicates that the stability networks need to load the circuit more
out-of-band in case the layout parasitic ground inductance is not low enough. There is
no way to totally eliminate the ground inductance, thus, more loading is employed. Since
the transistor high input reflection coefficient is causing the problem, loading the output
has little affect on stability for this circuit. Currently, the input is loaded with a parallel
240 Ω resistor at high frequencies. Loading only occurs at high frequencies because of
the 0.5 pF capacitor C1. Figure 21 shows the input reflection coefficient plotted on an
admittance plane Smith chart. The marker is moved to a location on the trace that has
the highest value of negative conductance. Now the reciprocal of the conductance gives
the additional parallel load necessary to move the input reflection coefficient magnitude
to the edge of the Smith chart. As indicated by the marker, an additional parallel input
load of 200 Ω is required to move the input reflection coefficient magnitude to unity. The
total parallel load is therefore 109 Ω. More margin is needed, thus the 240 Ω resistor
is adjusted to a smaller value and set to 50 Ω to stabilize the device input with greater
margin. Since the bypass input loading capacitor is small, the input parallel 50 Ω resistor
has little contribution to the circuit at 2.5 GHz.
23. 23
Figure 22. ATF54143amp1_1nH_Stabilize.dsn
Figure 22 shows the input parallel load resistor set to 50 Ω. The parasitic ground
inductance is still set to 1 nH. Figure 23 shows the analysis results. With the parallel
input 50 Ω resistor R1, the input reflection coefficient magnitude remains less than unity
at all frequencies from 10 MHz to 10 GHz. The 50 Ω gain is 7.47 dB which is only 0.01 dB
less than the case with the 240 Ω input parallel resistive load. This shows that the input
loading has little affect on the circuit at 2.5 GHz due to the 0.5 pF capacitor being used
as the bypass, but has a huge affect at higher frequencies. Since both input and output
reflection coefficient magnitudes remain less than unity when the circuit input and
output is terminated with 50 Ω, a stability analysis is now performed. Note that because
the input and output reflection coefficient magnitudes are less than unity, doesn’t mean
the circuit is unconditionally stable. There may still be source or load terminations other
than 50 Ω that can cause unwanted oscillations.
25. 25
S-Parameters, Noise Figure, Gain, Stability,
Circles, and Group Delay versus Frequency
Figure 24. ATF54143_StabilityAnalysis2.dsn
Figure 24 is a stability analysis from 100 MHz to 18 GHz with the parasitic ground
inductance set to 1 nH and the input parallel load resistor set to 50 Ω from Figure 22. The
50 Ω gain of 7.47 dB plotted in Figure 23 is not adequate gain for the 12 dB design goal.
Stability is checked for the case of 1 nH ground inductance before investigating the next
case of parasitic ground inductance.
Figure 25 is the same ADS Amplifier Design Guide data display from before that plots
Equations 7, 11, and 12 – stability factors K, μsource
, and μload
respectively. The circuit from
Figure 24 data indicates potential instability between 6 GHz and 9.5 GHz as shown in the
red box since μsource
< 1 and μload
< 1.
Before making any further adjustments to stabilizing networks, the parasitic ground
inductance L1 is adjusted down to 0.5 nH. The 1nH value was arbitrarily chosen to
begin with, so it is helpful to see how sensitive the circuit is when the parasitic ground
inductance is cut in half. Figure 26 shows the new circuit set up with the 0.5 nH parasitic
ground inductance L1 for the stability analysis.
26. 26
Figure 25. ATF54143_StabilityAnalysis2.dds
Figure 27 displays the Figure 26 simulation results with ground parasitic inductance
set to 0.5 nH. K, μsource
, and μload
are plotted and highlighted in the red box. The plot
indicates unconditional stability from 100 MHz to 18 GHz with more stability margin at
higher frequencies as desired. At this stage of the design, it is not yet known how much
parasitic ground inductance at the transistor source is contained in the PCB layout
because the layout is not yet started. Special attention is given to the layout procedure
to ensure that parasitic ground inductance at the transistor source is kept as low as
possible. Once the layout is complete, EM simulations give an estimate on the amount of
parasitic ground inductance. If estimated parasitic ground inductance is too high on the
initial layout, the layout is revised in an attempt to lower the PCB ground inductance
parasitic. Once electromagnetic (EM) simulations are performed on grounding and other
layout features, a stability and gain analysis with PCB layout parasitics included are
performed to ensure the amplifier meets all design objectives.
27. 27
S-Parameters, Noise Figure, Gain, Stability,
Circles, and Group Delay versus Frequency
Figure 26. ATF54143_StabilityAnalysis3.dsn
The gain, noise figure, and stability plots of Figure 25 show three spikes over the
100 MHz to 18 GHz frequency range. The transmission line used in the Coilcraft 27 nH
inductor model causes these spikes in the frequency response plots. The actual Coilcraft
inductor does not behave as suggested by the model above its self-resonance frequency.
A one-port measurement of the inductor is made using an E8364B network analyzer up to
6GHz and saved to a touchstone file named Lp1812SMS_27NG. This one-port measured
data file is now used in the amplifier circuit simulation to more accurately predict the
behavior of the amplifier circuit above the self-resonant frequency of the inductor up to
6 GHz. It was noticed during the inductor measurement that the results above the self
resonant frequency are sensitive to the position of the inductor in the fixture. These
variations cause more variability in the model prediction results above the 2.7 GHz
inductor self-resonant frequency. In other words, it is more difficult to get the circuit
model data to agree with final circuit measured data especially above the inductor self-
resonant frequency because of the measurement sensitivity.
28. 28
Figure 27. ATF54143_StabilityAnalysis3.dds
Figure 28 shows the amplifier circuit with the 27 nH inductor one-port s-parameter
measurements included in place of the Coilcraft lumped equivalent model. Figure 29
presents the Figure 28 simulation results. The inductor primary self-resonant frequency
response is still noticeable in the amplifier frequency response plots as expected,
although it is not as pronounced.
Figure 28. ATF54143_StabilityAnalysis4.dsn
29. 29
Maximum Available Gain is displayed and highlighted with orange boxes in Figures 27
and 29. The predicted maximum possible gain is around 10.8 dB in both figures. This
is 1.2 dB below the 12 dB design goal. Note that this predicted gain value is obtained
with an arbitrary estimated amount of transistor source terminal parasitic ground
inductance – 0.5 nH for Figures 27 and 29. Although the gain is below the target value in
these simulations, the gain without parasitic inductance is well above the target value.
A matching network is added at the amplifier input. In this case, a parallel inductor
followed by a series capacitor is added. These values have not yet been calculated, but
a preliminary match analysis indicates that the parallel inductor coming from the 50 Ω
source followed by a series capacitor going into the transistor input provides a valid
matching topology for the amplifier input. The matching design procedure is further
explained later for the final input matching analysis. The approximate matching inductor
value allows selection from a family of inductors that may be used. This allows a layout
of the inductor footprint. In this case, a CoilCraft air core inductor from the Mini-Spring
family of inductors provides a range of inductors suitable for the input matching network.
Next, the amplifier circuit is laid out with special attention to grounding the FET source
terminals. Once the layout is completed, an EM simulation predicts parasitic ground
inductance at the transistor source terminal. With an estimate of parasitic inductance,
new predictions of gain and stability are possible.
Figure 29. ATF54143_StabilityAnalysis4.dds
The amplifier is built on Arlon 25N, which is available in many standard laminate
thicknesses. Arlon 25N has a dielectric constant of 3.38 and a loss tangent of about
0.0023 at 2.5 GHz. Double-sided laminate having 1 ounce copper on each side, with a
30 ±3 mil thickness is selected for the design. Arlon 25N has a very consistent dielectric
constant over frequency and temperature and is easily processed by manufacturers that
process standard FR4 PCBs. Since performance specifications are very consistent and
repeatable, using the Arlon 25N material greatly enhances the possibility of completing
a one-pass design. In other words, the 25N material properties are used in the EM and
circuit simulations to get an accurate simulation of PCB and circuit performance before
resources are committed to actually building a board. Circuit repeatability from lot-to-lot
is also greatly increased due to the repeatability of the Arlon 25N material.
Amplifier EM/Circuit
Co-Simulation and PCB
Fabrication
30. 30
Figure 30 shows the amplifier layout top layer and Figure 31 shows the layout bottom
layer. All components are located on the top layer as shown by the figures. EM
simulations are now performed so that PCB effects can be included in the circuit
analysis. Each critical layout node is simulated individually and results combined with a
circuit analysis to include PCB effects. The EM/Circuit Co-Simulation feature in ADS is
then employed to combine the EM results with the circuit simulation. Linecalc is used to
design the input and output 50 Ω transmission lines. Each line is 250 mil long so that a
TRL calibration kit can be used for measurement. Arlon 25N material properties are used
in Linecalc to ensure correct line dimensions.
Figure 30. AvagoEnhGND.dsn – TopMetal
Figure 31. AvagoEnhGND.dsn – BottomMetal
31. 31
For the EM analysis, the substrate is first defined using the Arlon 25N material
properties and simulated from 10 MHz to 10 GHz. The “Substrate Layers” are defined as:
FreeSpace Boundary: Open Substrate Layer Name: FreeSpace
Permittivity: Loss Tangent Real: 1 Loss Tangent: 0
Permeability: Loss Tangent Real: 1 Loss Tangent: 0
Arlon25N Boundary: Interface Substrate Layer Name: Arlon25N
Thickness: 30mil
Permittivity: Loss Tangent Real: 3.38 Loss Tangent: 0.0023
Permeability: Loss Tangent Real: 1 Loss Tangent: 0
///GND/// Boundary: Closed Plane: Bulk conductivity in Siemens/meter
Conductivity: 5.8E7
The “Metalization Layers” are defined as follows:
FreeSpace
----Strip cond Layout Layer: Mapped to TopMetal, Sheet Conductor, Sigma 5.8E7S/m
Arlon25N Via Layer: Mapped to Plated Hole
///GND///
Once the substrate is computed, it is used for all PCB parasitic simulations. First, each
node is analyzed with the EM simulator to ensure convergence. Once each component
footprint parasitic is analyzed, a component is created from the Momentum Component
menu, which allows the ADS EM/Circuit Co-Simulation capability. Each node is labeled
in Figure 30 for reference.
Node 1 is labeled in Figure 30 and shown in Figure 32. This node connects the input
matching inductor to the amplifier input. The amplifier is first simulated without the
input matching network and then with the input matching network. For the first case,
the inductor is not connected at the amplifier input. Thus, the inductor footprint pad is
connected to the input microstrip line as shown in Figure 30. A “Single” port is used
for this EM simulation as shown in Figure 32. The EM simulation creates a one-port
s-parameter dataset named AvagoEnhNode1.
Figure 32. AvagoEnhNode1.dsn
32. 32
Node 2 is labeled in Figure 30 and shown in Figure 33. This trace connects the
input matching capacitor to the transistor gate, the feedback resistor R4 to the transistor
gate, and the input parallel load resistor R1 to the transistor gate. Four “Internal”
ports are used for the EM simulation setup since each component is soldered to the
footprint pad. The ports are connected to each pad center as shown in Figure 33. An EM
simulation creates a four-port s-parameter dataset named AvagoEnhNode2 for this PCB
trace.
Figure 33. AvagoEnhNode2.dsn
Node 3 is labeled in Figure 30 and shown in Figure 34. This PCB trace connects
the transistor drain to the series and parallel output loads R3 and R2, the transistor
drain to the 27 nH bias choke coil, and the transistor drain to a feedback DC blocking
capacitor. (The DC feedback blocking capacitor is put in series with feedback resistor
R4 to block the DC bias. This DC blocking capacitor was not included in the schematics
up to this point.) The footprint pad of the 27 nH choke inductor is quite large and would
add parasitic capacitance in parallel with the inductor, which in turn, would lower the
self-resonant frequency of the bias tee. Figure 34b is the actual trace on the PCB layout.
Since there would be a substantial amount of parasitic capacitance on this pad, it was
decided that the ground plane would be removed from beneath this pad on the bottom
layer (BottomMetal) to limit parasitic capacitance. Figure 31 shows the absence of
ground plane under the inductor footprint pad. The EM simulator assumes infinite ground
plane in all directions when it is set up in the simple case. Note, that the BottomMetal
layer could be defined as a layer in the EM simulator, and then an open boundary layer
could be defined below that layer. A ground reference port could be used to reference
the BottomMetal layer to ground. This approach would likely be more accurate, but
would require much more simulation time. This approach also requires a new substrate
definition and simulation for the added layers. Thus, the Arlon25N substrate definition is
not usable for the approach where BottomMetal is used as the ground reference. Instead
of the more complicated, time consuming approach, the inductor pad was removed and
not included on the trace for the EM simulation as shown in Figure 34a. This approach
is less accurate, but will simulate much faster and should capture most of the parasitic
effects of the trace. When the pad is removed, the fringe capacitance around the edge
of that pad would not be included as well as the inductance associated with the pad.
Although the pad is not included, an EM simulation should yield a good estimate of the
parasitics added by this particular trace. Five “Internal” ports are connected to each pad
center with the exception of the inductor pad removed. In this case, an internal port is
added to the trace end as shown in Figure 34a. An EM simulation creates a five-port
s-parameter dataset named AvagoEnhNode3a for this PCB trace.
33. 33
Figure 34. AvagoEnhNode3a.dsn EnhNode3b.dsn
Node 4 is labeled in Figure 30 and shown in Figure 35. This node connects the
output parallel load resistor R2 to the parallel load DC blocking capacitor C3. Two
“Internal” ports are connected to the pad centers as shown in the figure. An EM
simulation of this trace creates a two-port s-parameter dataset called AvagoEnhNode4.
Figure 35. AvagoEnhNode4.dsn
Node 5 is labeled in Figure 30 and is shown in Figure 36. This trace connects the
output series load resistor R3 to a series output DC blocking capacitor. The DC blocking
capacitor is added to block the DC from the amplifier output. It has not been included
in any simulations up to this point. Two “Internal” ports are connected to the pads as
shown. An EM simulation of this trace creates a two-port s-parameter dataset called
AvagoEnhNode5.
Figure 36. AvagoEnhNode5.dsn
Node 6 is denoted in Figure 30 and shown in Figure 37. This trace connects the
input parallel load resistor R1 to the 0.5 pF bypass capacitor C1, and connects gate
bias resistors to each other and to the input parallel load resistor R1 and 0.5 pF bypass
capacitor C1. A four-port s-parameter dataset called AvagoEnhNode6 is created upon
execution of an EM simulation of this PCB trace.
Figure 37. AvagoEnhNode6.dsn
34. 34
The feedback trace is shown in Figure 31 on the PCB. This trace is on the BottomMetal
layer underneath the TopMetal ground plane and connects the feedback resistor R4 to
the feedback capacitor. Thus, for the EM simulation, an assumption is made that the
trace is on the top of the PCB so that the existing Arlon25N substrate may be used for
the EM simulation. In other words, the BottomMetal layer is mapped to the top of the
substrate and the TopMetal layer is mapped to the GND plane. In reality, the runner is
actually copied to the TopMetal layer and no mapping of the BottomMetal layer occurs.
Thus, the runner in Figure 38 is on the substrate top layer and the bottom layer is
a ground plane for the EM simulation. The vias cutting through the PCB on the actual
layout are not included in the EM simulation since they would be shorted to ground.
The footprint pads for the feedback resistor R4 and feedback DC blocking capacitor are
also not included. This is an estimate that includes most of the parasitic effects of the
feedback runner. A “Single” port is used on each end of the runner as shown in Figure
38. A twoport s-parameter dataset is created upon completion of the EM simulation.
Figure 38. AvagoEnhFB.dsn
Finally, an estimate of parasitic ground inductance on the transistor source leads
is simulated. The transistor has two source leads that are connected internally to each
other. For the source terminal parasitic ground inductance estimate, an EM simulation
is performed at the connection point of each transistor source lead on the PCB. Since
the transistor s-parameter data uses a two-port representation that has only one ground
reference, the inductance value estimates for the two lead connections are combined
as parallel inductances to obtain one parasitic ground inductance value for the circuit
simulations. According to the Avago 54143 data sheet, the s-parameters are measured in
a fixture that has vias tying the source terminals to ground. This adds some uncertainty to
the end result of actual amplifier performance versus model performance. An estimate of
ground inductance on the PCB layout is accomplished with an EM simulation. The Arlon
25N substrate is set up with an infinite ground plane on the bottom layer. Using this
approach is likely to under-estimate the parasitic inductance. An alternate approach
changes the bottom layer of the substrate to a strip layer like the top layer and maps the
BottomMetal layer to this new bottom strip layer. An open boundary layer is added below
the bottom metal layer. A ground reference port is now added to the BottomMetal layer.
Placement of this ground reference port on the BottomMetal layer is problematic. Where
is the actual ground reference? No two points on the bottom ground layer are at the exact
same RF voltage potential since there is inductance and loss in the ground plane. Thus,
placement of the ground reference port will affect analysis results.Parasitic inductance is
likely to be higher and more realistic with this approach, but the simulation time is longer.
Since an estimate of parasitic ground inductance is the objective, the first method is used
for simulation.
Figure 39 shows a portion of the layout where vias connect the top layer metal to
the bottom layer metal. An “Internal” port is added to the TopMetal layer where the thin
transistor source leg connects to the PCB. The Arlon25N substrate is used for the EM
simulation. Edge meshing is not used and the analysis is performed only at 2.5 GHz. Upon
completion of the EM simulation a one-port s-parameter dataset is created.
35. 35
Figure 39. AvagoEnhViasThinLegLessVias.dsn
Figure 40. AvagoEnhViasThinLegLessVias.dds
Figure 40 shows the results of the first parasitic ground inductance simulation.
The inductive reactance is j(50 × 0.038) = j1.9 as shown on the Smith chart marker
readout. Solving for the inductance value:
Equation 26.
Figure 41. AvagoEnhViasThinLeg.dsn
Figure 41 has 4 additional vias added close to the transistor thin leg in an attempt to
lower the parasitic ground inductance. The internal port is in the same location as in
Figure 39. The 2.5 GHz EM simulation creates a one-port s-parameter dataset. Figure
42 plots the data on a Smith chart as shown. The marker readout yields the inductive
reactance j(50 × 0.017) = j0.85, which is less than half of the parasitic inductive
reactance from the first case. Solving for the inductance value:
1.9
2 π (2.5x109
)
XL
2 π f
= 0.1214 nH=
36. 36
0.85
2 π (2.5x109
)
XL
2 π f
= 0.0541nH=
The four extra vias are included in the layout since they lower the parasitic inductance
value to less than half.
Figure 43 shows the setup for estimating parasitic ground inductance where the
wide transistor source leg connects to the TopMetal layer. The internal port connects
where the center of the transistor lead attaches. The EM simulation creates a one-port
s-parameter dataset that is plotted in Figure 44. The marker readout lists inductive
reactance j(50 × 0.0505) = j2.526 as shown in the figure. Solving for the inductance value:
2.526
2 π (2.5x109
)
XL
2 π f
= 0.1608nH=Equation 28.
Figure 42. AvagoEnhViasThinLeg.dds
Figure 43. AvagoEnhViasWideLeg.dsn
Equation 27.
37. 37
Figure 44. AvagoEnhViasWideLeg.dds
The two calculated inductance values of 0.05447 nH and 0.1608 nH are now put in
parallel to obtain an estimate of parasitic inductance. Note that putting the inductance
values in parallel with each other is a very crude approach, but will likely give a decent
ballpark estimate of parasitic ground inductance. Putting the inductances in parallel
yields an estimated parasitic ground inductance of 0.045 nH. An alternate approach to
putting the inductance values in parallel would be to use the nonlinear model for the
simulation since it includes both source leads. Then, the narrow transistor leg calculated
parasitic ground inductance is connected to the narrow source leg and the wide leg
calculated parasitic ground inductance is connected to the wide source leg and used
for simulation. Note also that the Avago measured s-parameter data was measured in a
fixture with vias that add parasitic ground inductance.
Figure 45 combines the PCB layout node of each PCB layout trace with the circuit
component models to EM/Circuit Co-Simulate the entire circuit with layout parasitics.
Each PCB trace was first simulated with the EM simulator to produce a multiport
s-parameter dataset.
Figure 45. ATF54143ampEM.dsn
38. 38
Figure 45 contains the estimated parasitic ground inductance represented by the
L1 inductor. Measured data for the 0.1 uF capacitor is included for the DC blocking
capacitors and DC bypassing capacitors as well.
Figure 46 plots the Figure 45 s-parameter simulation data. Note that the input
matching network is not yet included in the Figure 45 schematic. It is useful to analyze
amplifier stability results without matching networks since matching networks can
decouple the gain block from the measurement system at some frequencies. The
50 Ω gain is 14.2 dB according to Figure 46. Notice the resonance at 3.3 GHz caused by
the output choke coil. This resonance is seen in the S11, S22, S21, and S12 plots. The
output reflection coefficient is low at low frequencies below the primary resonance. It
is therefore, unlikely that the amplifier requires an output matching network. The input
reflection coefficient below the primary resonance indicates that a matching network will
improve amplifier input return loss. Input matching also impacts amplifier noise figure as
indicated by Equation 27.
Figure 46. ATF54143ampEM.dds
39. 39
S-Parameters, Noise Figure, Gain, Stability,
Circles, and Group Delay versus Frequency
Figure 47. ATF54143_StabilityAnalysis5.dsn
A stability analysis of the amplifier circuit, which includes PCB layout and component
parasitics is shown in Figure 47. This ADS Amplifier Design Guide not only calculates
stability factors K, μSource
, and μLoad
, but also allows an available gain design with available
gain circles and noise circles. The stability analysis is limited from 100 MHz to 6 GHz
since the choke inductor measured data is limited to 6 GHz. Figure 48 shows K, μSource
,
and μLoad
plotted in the red box. Note that μSource
≥ 1 and μLoad
≥ 1 for all frequencies from
100 MHz to 6 GHz, either of which, guarantee unconditional stability over that frequency
range.
Available gain circles are plotted with noise circles in Figure 49. Figure 50 gives specific
readouts for Figure 49. The minimum noise figure, NFmin
, is 1.23 dB according to Figure
48. The first noise circle is 0.2 dB higher than NFmin
, or 1.4 dB. The 1.4 dB noise circle
passes right through ΓMS
, the simultaneous conjugate input match. Thus, the marker is
moved to the 1.4 dB noise figure circle at ΓMS
.
41. 41
The marker readout in the red box of Figure 50 shows the impedance that must be
presented to the amplifier input to achieve 1.42 dB noise figure and 15.6 dB of gain.
The impedance of 18.338-j14.722 is what the amplifier input “wants to see” to obtain
these results. It is also assumed that the output will be conjugately matched when the
amplifier input is terminated with this impedance. In reality, the amplifier output doesn’t
require much output matching since it’s output reflection coefficient is already pretty
low. Thus, the last step of the available gain design procedure, which is to conjugately
match the output for the given source termination, will not be executed. The expected
gain of 15.6 dB will not be reached, but will be reduced by a very small amount.
The input match must transform 50 Ω to 18.338-j14.722 at 2.5 GHz. An ADS Matching
Design Guide is used to develop the matching network. The Design Guide assumes that
one impedance is being matched to another impedance, whereas, the Figure 50 marker
readout is what the amplifier input “wants to see”. Figure 51 demonstrates how the
reference is changed from what the amplifier “wants to see” at its input to how the ADS
Matching Network Design Guide is configured.
Figure 51. Matching References
Figure 52. InMatch_Synthesis.dsn
42. 42
S-Parameters, Noise Figure, Gain, Stability,
Circles, and Group Delay versus Frequency
The input matching network is designed using the ADS Matching Network Design Guide
as shown in Figure 52 and demonstrated in Figure 51. An L-match is designed consisting
of a parallel 2.42 nH inductor next to the 50 Ω source and a series 1.64 pF capacitor
connected to the amplifier input as displayed in Figure 52.
Figure 53 adds the ideal input matching network to the Figure 47 amplifier, which
contains PCB and lumped component parasitics. Note that the 2.4 nH parallel inductor is
connected in parallel with the 50 Ω source and the 1.6 pF series capacitor then connects
to the amplifier input. The inductor is not connected to the inductor pad from the Node1
EM simulation since the first Node1 EM simulation is a one-port s-parameter dataset.
Figure 53. ATF54143_InMatch.dsn
The Figure 53 s-parameters are plotted in Figure 54. The Smith charts indicate
both the input and output are well matched at 2.5 GHz. The numeric gain on the S21
polar chart at 2.5 GHz is 5.53, which converts to 14.85 dB.
43. 43
Figure 54. ATF54143_InMatch.dds
A gain of 15.15 dB at 2.4 GHz is plotted on the rectangular plot of Figure 55. A 20 dB
input return loss and 10 dB output return loss are also plotted. The predicted noise figure
with the input match is 1.56 dB at 2.5 GHz.
A 2.4 nH Coilcraft airwound inductor is available for the input matching network.
A lumped equivalent model supplied by Coilcraft is shown in Figure 56. The subcircuit
model is created for use in the amplifier circuit.
45. 45
S-Parameters, Noise Figure, Gain, Stability,
Circles, and Group Delay versus Frequency
Figure 57. ATF54143_InMatch2.dsn
The lumped equivalent 2.4 nH Coilcraft inductor L3 replaces the ideal inductor in
Figure 53 to give the Figure 57 circuit. Figure 58 plots the simulation results of Figure 57.
S11 and S22 Smith chart plots indicate that both input and output are very well matched.
The input return loss with the inductor model plotted in Figure 59 shows a slight
degradation from 20 dB to 17.6 dB. The 15.14 dB gain is unaffected by the slight input
loss degradation. The 2.4 nH coil loss slightly degrades noise figure to 1.62 dB.
Figure 58. ATF54143_InMatch2.dds
46. 46
freq nf(2)
100.0 MHz
200.0 MHz
300.0 MHz
400.0 MHz
500.0 MHz
600.0 MHz
700.0 MHz
800.0 MHz
900.0 MHz
1.000 GHz
1.100 GHz
1.200 GHz
1.300 GHz
1.400 GHz
1.500 GHz
1.600 GHz
1.700 GHz
1.800 GHz
1.900 GHz
2.000 GHz
2.100 GHz
2.200 GHz
2.300 GHz
2.400 GHz
2.500 GHz
2.600 GHz
2.700 GHz
2.800 GHz
2.900 GHz
3.000 GHz
46.297
34.385
27.488
22.656
18.964
16.007
13.565
11.513
9.574
8.483
7.261
6.206
5.296
4.514
3.848
3.288
2.825
2.451
2.157
1.950
1.788
1.681
1.622
1.605
1.616
1.658
1.726
1.816
1.924
2.046
Figure 59. ATF54143_InMatch2.dds
Figure 60. ATF54143ampEM2.dsn
The Node1 one-port s-parameter EM simulated dataset is replaced by the two-port
s-parameter data so that the lumped equivalent circuit model is connected correctly to
the PCB trace pad. Previously, the AvagoEnhNode1 was treated as a one-port network
and the 2.4 nH matching inductor was placed in parallel with that trace representation.
Further, and more importantly, the 2.4 nH Coil Craft lumped equivalent model is replaced
by one-port measured data in Figure 60. The 2.4 nH matching inductor attaches to
the pad center, thus the updated Node1 trace is used in Figure 60. Figure 61 plots the
updated simulation results. The measured data for the 2.4 nH input matching inductor
indicates that the lumped equivalent model under-estimates loss of the actual inductor.
Gain degrades from 15.137 dB to 14.65 dB and noise figure degrades from 1.6 dB to
1.78 dB at 2.5 GHz as shown by Figures 59 and 61.
48. 48
Amplifier Nonlinear
Analysis
Figure 62. ATF54143_Amp_HBT2Tone.dsn
Figure 63. ATF541413_Amp_HBT2Tone.dds
A third order intermodulation distortion simulation is configured using the ADS
Amplifier Design Guide (from a schematic, select DesignGuide > Amplifier > 2-Tone
Nonlinear Simulations > Spectrum, Gain, TOI and 5th OI Points) in Figure 62. The Figure
60 ATF54143 two-port s-parameter data is replaced in the parasitic model by the biased
non-linear model from Figure 5. The red box in Figure 63 displays a third order input
intercept point of 7 dBm.
49. 49
Specification
requirement
Simulated value
Frequency range 2.4 GHz to 2.48 GHz 2.4 GHz to 2.48 GHz
Gain > 12 dB 14.65 dB
Noise figure < 2.5 dB 1.78 dB
IP3i > 0 dBm 7 dBm
Input return loss > 10 dB 12.7 dB
Output return loss > 10 dB 13.6 dB
Current drain < 100 mA 61.38 mA
Supply voltage 3.3 V 3.3 V
Stability Unconditional Unconditional
Table 3.
Since the simulated amplifier with all PCB layout and component parasitics meet or
exceed the specification requirements, the PCB layout of Figures 30 and 31 is fabricated.
Additionally, it is convenient to design and construct a TRL calibration kit so that precise
measurements are possible without the need of de-embedding procedures. Linecalc is
again used to design the TRL calibration standards. Required standards include an Open,
Load, Thru, and at least one Line. Since the amplifier input and output 50 Ω transmission
lines are 250 mils long in Figure 30, the Open standard is also 250 mils long. The Thru is
made twice as long so that a zero length Thru is constructed. Thus, the zero length Thru
is 500 mils long. The Load standard is used for the isolation calibration and also has a
length of 250 mils. Next a Line standard is constructed. The Intercontinental Microwave
transistor calibration data is valid to 6 GHz, thus the TRL calibration Line 1 standard is
designed to cover up to 6 GHz. The electrical length of the line standard is valid from 30°
to 150°. Thus, the Line 1 standard should be no longer electrically than 150° at 6 GHz.
Using Linecalc, the physical line length is 500 mils. Thus, the Line 1 standard is the
500 mil electrical length of the zero length Thru standard plus the additional Line 1 length
of 500 mils, yielding a total Line 1 length of 1000mils. The lowest frequency for the Line 1
standard that yields an electrical length of 30° is just above 1.2 GHz, therefore 1.3 GHz is
used as the Line 1 standard lower frequency limit. Therefore, the Line 1 standard, which
is physically 500 mils long, covers a frequency range of 1.3 GHz to 6 GHz. The electrical
delay of the Line 1 standard is given by:
TRL Calibration Kit
The simulated amplifier that includes PCB layout and component parasitics meets all
amplifier design requirements as follows:
Simulation Results
Versus Specification
Requirements
τ =
1
c
√
2.997925E8
εr √.0127m 2.66
m
sec
= = 69.1pSecEquation 29.
The TRL zero length Thru standard measures 500 mils long and is shown in
Figure 64. The TRL Open standard is 250 mils long and is shown in Figure 65. The TRL
Load standard used for the isolation calibration is 250 mils long and shown in Figure 66.
The TRL Line 1 standard measures 1000 mils long and is shown in Figure 67.
51. 51
Figure 66. Load25N.dsn
Figure 67. Line1_25N.dsn
The Standard Class Assignments for the Arlon 25N TRL calibration kit are shown in Table
4. The Arlon 25N Standard Definitions are shown in Table 5. Other Line standards listed in
Tables 4 and 5 are available in the Arlon 25N TRL calibration kit, which are developed in a
similar fashion to the Line 1 Calibration Standard.
52. 52
CLASS A B C D E F G Standard Class Label
S11
A 1 Open
S11
B
S11
C 3 Load
S22
A 1 Open
S22
B
S22
C 3 Load
Forward Transmission 2 Thru
Reverse Transmission 2 Thru
Forward Match 2 Thru
Reverse Match 2 Thru
Response
Response & Isolation 3 Isoln Std
TRL Thru 2 Thru
TRL Reflect 1 Open
TRL Line 4 5 6 7 8 9 Lines
Adapter
TRL Option
Cal Z0
: _____ System Z0
_____ Line Z0
Set Ref: __x__ Thru _____ Reflect
Standard Class Assignments Calibration Kit _____Arlon25N
STANDARD
C0
10-15
F
C1
10-27
F/Hz
C2
10-36
F/Hz2
C3
10-45
F/Hz3 Fixed
or
Sliding
Terminal
Impedance
Ω
Offset
Frequency
(GHz) Coax or
Waveguide
Standard
Label
# TYPE
L0
10-12
H
L1
10-24
H/Hz
L2
10-33
H/Hz2
L3
10-42
H/Hz3
Delay
pSec
Z0
Ω
Loss
GΩ/s
MIN MAX
1 Open 0 0 0 0 50 0 154.8 0.2 20 Open
2 Thru 50 0 50 0.2 20 Thru
3 Load Fixed 50 0 120.9 0.2 20 Load
4 Line 1 50 69.1 50 1.3 6 1.3-6 Line
5 Line 2 50 207.31 50 0.4 2 0.4-2 Line
6 Line 3 50 19.348 50 4.5 20 4.5-20 Line
7 Line 4 50 20.177 50 4.2 20 4.2-20 Line
8 Line 5 50 96.74 50 0.87 4.3 0.87-4.3 Line
9 Line 6 50 428.42 50 0.2 0.97 0.2-0.97 Line
10
Calibration Kit: Arlon25N
Table 5.
Table 4.
53. 53
Figure 68 shows the amplifier and TRL calibration standards fabricated on Arlon 25N
30 mil thick PCB laminate.
Fabricated Amplifier
and TRL Calibration
Standards
Figure 68. Fabricated amplifier and TRL calibration kit
The Table 4 and Table 5 calibration coefficients are entered into the network analyzer.
The network analyzer is now calibrated using the Arlon 25N TRL calibration kit using
the Line 1 standard. This allows a calibration over the frequency range from 1.3 GHz to
6 GHz. The amplifier input matching network is not yet placed on the PCB. (The input
matching network is shown in Figure 68.) A DC blocking capacitor C5 is used at the input
instead of the 1.6 pF matching capacitor in order to measure the amplifier s-parameters
without the input matching network. The measured s-parameter data is saved to a data
file and pulled into the simulator using Figure 69. Measured amplifier s-parameter data is
plotted in Figure 70. Unmatched gain at 2.5 GHz is shown at 13.26 dB.
Amplifier Linear
S-Parameter
Measurements
Using TRL
Figure 69. ATF54143Amp_NoInputMatch.dsn
55. 55
S-Parameters, Noise Figure, Gain, Stability,
Circles, and Group Delay versus Frequency
Figure 71 allows a stability analysis on the measured s-parameter data from 1.3 GHz to 6
GHz. Stability analysis results are plotted in Figure 72. The red box highlights μSource
and
μLoad
plots. Note that μSource
≥ 1 and μLoad
≥ 1 for all frequencies from 1.3 GHz to 6 GHz,
either of which, guarantee unconditional stability over that frequency range. Thus, the
measured s-parameters indicate unconditional stability.
Figure 71. ATF54143_StabilityAnalysis6.dsn
Figure 72. ATF54143_StabilityAnalysis6.dds
56. 56
Figure 73 compares the simulated amplifier using red traces with the measured
amplifier using blue traces. Good agreement is shown between the two results.
Measured gain at 2.5 GHz is 13.26 dB whereas the model predicts 14.2 dB. Gain is very
sensitive to source terminal ground inductance shown by previous analysis. Source
terminal inductance is analyzed with EM simulation for both transistor source terminals.
Then, these two inductances are combined in parallel to use in the circuit simulation.
Some method of combining the two inductances is necessary since an s-parameter
linear component in ADS has only one ground reference terminal. The input reflection
coefficient at 2.5 GHz is slightly higher for the measured amplifier versus the simulated
amplifier. This accounts for a portion of the measured amplifier lower gain versus the
simulated amplifier in the unmatched case. The method of combining parasitic transistor
source terminal inductance and the higher input reflection coefficient of the measured
amplifier easily leads to the gain discrepancy between modeled and measured results.
Note that the measured amplifier exceeds the 12 dB gain requirement.
Measured Versus
Modeled
Figure 73. ATF54143Amp_NoInMatchCompare.dds
57. 57
The input matching network is now added by removing the DC blocking capacitor C5 at
the amplifier input and replacing it with the 1.6 pF matching capacitor and adding the
2.4 nH Coil Craft air wound inductor at location L3 (Lmatch). S-parameter measurements
using the TRL calibration procedure are repeated on the amplifier with the matching
network in place. Figure 74 brings the measured data into ADS as shown.
Figure 74. ATF54143_InMatchMeasured.dsn
Figure 75 plots the amplifier measured s-parameter data with the input matching
network in place. The measured gain of 13.62 dB is shown along with an input return
loss of 9.7 dB and an output return loss of 13.6 dB. The measured gain is slightly below
the simulated value (14.2 dB) as was the case for the unmatched gain case because
of the method used to estimate source ground parasitic inductance. The actual gain
exceeds the 12 dB specification requirement with margin, and is therefore acceptable.
Note that the input return loss of 9.7 dB marginally fails the 10 dB specification
requirement, but will also be accepted in this particular design since the input return
loss is considered to be a “soft” or negotiable specification. The output return loss of
13.64 dB exceeds the 10 dB goal with some margin. Figure 76 plots the simulated
amplifier on the same graphs as the measured amplifier for an easier comparison. Note
that the plots show a close agreement between simulated and measured data.
The noise figure and third order intercept point are now measured on the amplifier
and compared to the simulated values. Noise figure is measured at 1.91 dB and input
third order intercept point at 2.45 GHz is 13.6 dBm. The simulated noise figure of
1.78 dB closely predicts the measured value. The measured third order input intercept
point of 13.7 dBm is substantially better than the 7 dBm simulated value. An Avago
representative confirms that nonlinear performance of the actual device is somewhat
better than modeled performance. Note that the measured nonlinear performance is
significantly better than the 0 dBm specification requirement.
60. 60
Specification
requirement
Simulated
value
Measured
value
Frequency range 2.4 GHz to 2.48 GHz 2.4 GHz to 2.48 GHz 2.4 GHz to 2.48 GHz
Gain > 12 dB 14.65 dB 13.62 dB
Noise figure < 2.5 dB 1.78 dB 1.91 dB
IP3i > 0 dBm 6.9 dBm 13.7 dBm
Input return loss > 10 dB 12.7 dB 9.7 dB
Output return loss > 10 dB 13.6 dB 13.6 dB
Current drain < 100 mA 61.38 mA 63 mA
Supply voltage 3.3 V 3.3 V 3.3 V
Stability Unconditional Unconditional Unconditional
Table 6.
The simulated and measured amplifier that includes PCB layout and component
parasitics meets all amplifier design requirements as illustrated in Table 6:
Conclusion
Table 6 indicates that the first-pass amplifier exceeds most of the requirements.
The input return loss is marginal but acceptable. The input match could be adjusted
slightly to improve input return loss at the possible expense of noise figure. One of the
main objectives was to obtain a working design with the first pass layout. The procedure
is considered successful as long as the layout does not have to be altered to obtain a
working circuit. The procedure is also considered a success if the components had to be
slightly adjusted to achieve performance without a layout modification. In this case, the
circuit components did not require adjustment to meet the objectives.
Using the EM/Circuit Co-Simulation capability in ADS allows a first-pass design.
Careful attention to layout and simulation results speeds the design process and provides
a design cost savings by avoiding multiple pass PCB designs. Note also that the entire
PCB does not have to be simulated with the EM simulator to obtain good results. Putting
the entire PCB in the simulator may improve the results at the expense of significantly
longer simulation time.
61. 61
Agilent Technologies, Product Note 8510-8A, Agilent Network Analysis Applying the 8510
TRL Calibration for Non-Coaxial Measurements, Agilent Technologies, 2000.
Les Besser, Applied RF Techniques I, Besser Associates, Los Altos, CA, 1995.
Guillermo Gonzalez, Microwave Transistor Amplifiers Analysis and Design, Prentice-Hall,
Inc., Englewood Cliffs, NJ, 1984.
H. L. Krauss, W. Bostian, and F. H. Raab, Solid State Radio Engineering, John Wiley &
Sons, NY, 1980.
Mario A. Maury, Jr., Steven L. March, Gary R. Simpson, Application Note 5A-017 LRL
Calibration of Vector Network Analyzers, Maury Microwave Corporation, 1999.
Ken Payne, Wireless Measurements, Theory and Practice, Besser Associates, Los Altos,
CA, 1998.
KEN PAYNE began his engineering career at RCA, developing circularly polarized TV and
FM broadcast antennas and feed systems. He was also involved with wide bandwidth
receivers and transmitters, covering from DC to 1GHz, for fiber-optic test equipment.
Later, at Motorola’s Communications Division, he designed RF amplifiers, mixers, filters,
oscillators, antennas and other transceiver circuits and systems for two-way portable
and paging products. He developed and directed circuit and system design projects
and created a wide range of active and passive RF device models for the HP-EEsof
Microwave Design System (MDS) and Advanced Design System (ADS). In addition, Ken
also developed RF and microwave design automation, measurement techniques, and
interfaces between design workstations and test equipment. As a sideline, he conducted
seminars and wrote articles on design methodologies for high performance, low-cost,
and high-yield wireless communication circuits and systems. Ken was an instructor for
Besser Associates and CEI of Europe for many years where he gave training seminars on
RF design and measurement methodologies. Ken was one of the authors of the Oscillator
Design Guide available in ADS. Ken now provides consulting services in RF/microwave
design.
References