This document is a dissertation proposal by Benjamin Braaten on properties of multiple microstrip antennas in layered anisotropic materials. The proposal provides background on microstrip antennas and previous related work. It then outlines the proposed research questions on determining input impedance and mutual impedance of antennas in layered anisotropic structures. The technical objectives and work plan involve choosing antenna types, developing numerical techniques, and validating results with experiments on designed structures. The proposal seeks to advance understanding of antenna properties in complex layered anisotropic materials.
Top Downloaded Articles in Electromagnetics - March 2021ijeljournal
International Journal of Electromagnetics invites high quality manuscripts in the research areas of electromagnetic modelling, analysis and implementation. The journal proposes to stimulate the development of latest technology in industry and academia. Good quality review papers and short communications are also acceptable.
This document summarizes the design of a single-layer microstrip antenna with symmetrical Y-slots to achieve wide bandwidth. The antenna is designed on an FR4 substrate with a square patch measuring 30mm x 30mm and two symmetrical Y-slots and a rectangular slot on the patch. Electromagnetic simulations show the antenna achieves a return loss below -10dB from 4.04GHz to 5.12GHz, providing a 22% bandwidth. The antenna has a maximum gain of 4.33dBi and directive gain between 7.16-8.06dBi within the operating bandwidth, making it suitable for wireless applications.
The document describes the design of a microstrip patch antenna with an inset feed for WiMAX and WLAN applications. It has the following key points:
1. The antenna is designed on a glass epoxy substrate with a dielectric constant of 4.4 to provide a wide bandwidth of 88.57% covering 1.01-2.62 GHz.
2. An inset feed technique is used which provides easy modeling, matching of the feed line, and fabrication.
3. Simulation results show the antenna has high gain up to 6 dBi and radiation efficiency of about 99%.
This document describes an experiment measuring the permittivity and permeability of FR-4 material and simulating it numerically. It was submitted by Neetesh Sharma for their dissertation under the guidance of Ashish Duvey. The objective was to develop a new approach to enhance the bandwidth and improve the performance of microstrip patch antennas by designing the antenna to optimize bandwidth enhancement, return loss reduction, and directivity improvement using CST simulation software and validating properties with MathCAD and Excel. Formulas are provided for calculating antenna width, effective dielectric constant, length extension, and actual length based on permittivity and permeability. Applications of microstrip patch antennas and an overview of metamaterials including definitions, classifications such as DNG materials,
Design and simulation of fractal tree antenna for wireless applicationIAEME Publication
This document discusses the design and simulation of a fractal tree antenna for wireless applications. It provides background on fractal antennas and their advantages, such as multiband performance and reduced size. The document then describes the geometry of two types of fractal trees known as Pythagorean trees and ternary fractal trees that can be used for antenna design. It proposes a new design for a fractal tree antenna based on the ternary fractal tree geometry for use in wireless local area networks operating at 2.4GHz. Key parameters for the fractal tree antenna design include the initial segment size, scale factor, branching angle, and number of iterations.
Communication has become a key aspect of our daily life, becoming increasingly portable and mobile. This would need the use of micro strip antennas. The rapid growth has led to the need of antennas with smaller size, increased bandwidth and high gain. In this paper, a new version of micro strip patch antenna is designed by adopting double layered substrate concept and adding a layer of metamaterial structure to a square micro strip antenna. The antenna properties gain, return loss and bandwidth are studied to achieve better performance. The designed patch antenna has an improved bandwidth of 60% at a resonant frequency of 2.47 GHz. This antenna is designed and simulated by using HFSS software.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
(1) The document discusses frequency selective surfaces (FSS), which are periodic structures that perform filtering at microwave frequencies. FSS performance depends on factors like element geometry, conductivity, substrate properties, and array period/number.
(2) CST Microwave Studio is used to model and analyze FSS. An annular ring FSS design is proposed for dual-band operation in C-band and X-band. Simulation results show the resonant frequencies can be shifted by varying the ring spacing.
(3) Testing different substrate materials, a linear relationship is observed between the shift in bands, demonstrating the design's ability to achieve dual-band response through proper element and substrate selection.
Top Downloaded Articles in Electromagnetics - March 2021ijeljournal
International Journal of Electromagnetics invites high quality manuscripts in the research areas of electromagnetic modelling, analysis and implementation. The journal proposes to stimulate the development of latest technology in industry and academia. Good quality review papers and short communications are also acceptable.
This document summarizes the design of a single-layer microstrip antenna with symmetrical Y-slots to achieve wide bandwidth. The antenna is designed on an FR4 substrate with a square patch measuring 30mm x 30mm and two symmetrical Y-slots and a rectangular slot on the patch. Electromagnetic simulations show the antenna achieves a return loss below -10dB from 4.04GHz to 5.12GHz, providing a 22% bandwidth. The antenna has a maximum gain of 4.33dBi and directive gain between 7.16-8.06dBi within the operating bandwidth, making it suitable for wireless applications.
The document describes the design of a microstrip patch antenna with an inset feed for WiMAX and WLAN applications. It has the following key points:
1. The antenna is designed on a glass epoxy substrate with a dielectric constant of 4.4 to provide a wide bandwidth of 88.57% covering 1.01-2.62 GHz.
2. An inset feed technique is used which provides easy modeling, matching of the feed line, and fabrication.
3. Simulation results show the antenna has high gain up to 6 dBi and radiation efficiency of about 99%.
This document describes an experiment measuring the permittivity and permeability of FR-4 material and simulating it numerically. It was submitted by Neetesh Sharma for their dissertation under the guidance of Ashish Duvey. The objective was to develop a new approach to enhance the bandwidth and improve the performance of microstrip patch antennas by designing the antenna to optimize bandwidth enhancement, return loss reduction, and directivity improvement using CST simulation software and validating properties with MathCAD and Excel. Formulas are provided for calculating antenna width, effective dielectric constant, length extension, and actual length based on permittivity and permeability. Applications of microstrip patch antennas and an overview of metamaterials including definitions, classifications such as DNG materials,
Design and simulation of fractal tree antenna for wireless applicationIAEME Publication
This document discusses the design and simulation of a fractal tree antenna for wireless applications. It provides background on fractal antennas and their advantages, such as multiband performance and reduced size. The document then describes the geometry of two types of fractal trees known as Pythagorean trees and ternary fractal trees that can be used for antenna design. It proposes a new design for a fractal tree antenna based on the ternary fractal tree geometry for use in wireless local area networks operating at 2.4GHz. Key parameters for the fractal tree antenna design include the initial segment size, scale factor, branching angle, and number of iterations.
Communication has become a key aspect of our daily life, becoming increasingly portable and mobile. This would need the use of micro strip antennas. The rapid growth has led to the need of antennas with smaller size, increased bandwidth and high gain. In this paper, a new version of micro strip patch antenna is designed by adopting double layered substrate concept and adding a layer of metamaterial structure to a square micro strip antenna. The antenna properties gain, return loss and bandwidth are studied to achieve better performance. The designed patch antenna has an improved bandwidth of 60% at a resonant frequency of 2.47 GHz. This antenna is designed and simulated by using HFSS software.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
(1) The document discusses frequency selective surfaces (FSS), which are periodic structures that perform filtering at microwave frequencies. FSS performance depends on factors like element geometry, conductivity, substrate properties, and array period/number.
(2) CST Microwave Studio is used to model and analyze FSS. An annular ring FSS design is proposed for dual-band operation in C-band and X-band. Simulation results show the resonant frequencies can be shifted by varying the ring spacing.
(3) Testing different substrate materials, a linear relationship is observed between the shift in bands, demonstrating the design's ability to achieve dual-band response through proper element and substrate selection.
This document summarizes a research paper that surveyed techniques used to enhance the performance of patch antennas using metamaterials. Metamaterials are artificially designed materials that can exhibit unusual electromagnetic properties not found in nature. They have been used in the last decade to design more compact and higher performance patch antennas for microwave applications. The document discusses various metamaterial-inspired patch antenna designs that have improved gain, directivity, bandwidth, side lobe suppression, and radiation efficiency. It also reviews the different types of metamaterials and how they provide solutions to challenges in conventional patch antenna design like small size and narrow bandwidth. In conclusion, it identifies open issues that could help guide future research in this area.
Review: Dual Band Microstrip Antennas for Wireless ApplicationsIJAAS Team
In this manuscript, a review of dual band microstrip antennas for wireless communication is presented. This review manuscript discusses regarding the geometric structures, different methods of analysis for antenna characteristics, and different types of wireless applications.
This document describes the design of a patch antenna that can operate at multiple frequency bands using metamaterials. A rectangular patch antenna is designed to operate at 3 GHz. Then, a unit cell of complementary split-ring resonator (CSRR) is designed to also operate at 3 GHz. An array of this CSRR unit cell is placed on the patch to act as a metamaterial and enable multiband operation. Specifically, the antenna is designed to resonate in the Bluetooth, WiMax and Wi-Fi bands. Simulation results using HFSS software show that the proposed antenna provides good performance in terms of voltage standing wave ratio, return loss and impedance matching for multiband operation.
Role of geometry of split ring resonators in magneticIAEME Publication
This document discusses the role of geometry in split ring resonators (SRRs) and magnetic resonance in metamaterials. It contains the following key points:
1) SRRs are the basic building blocks of metamaterials and allow control of magnetic response and negative permeability. Their geometry, including ring size, gap, spacing, substrate thickness, and material properties can be varied to control resonant frequency.
2) SRRs can be modeled as LC circuits, where the ring acts as an inductor and the gap as a capacitor. Resonant frequency depends inversely on size and dielectric properties.
3) Finite element method software is used to simulate SRR units and calculate effective permeability from scattering parameters
This document provides a review of metamaterials. It begins by discussing how metamaterials can overcome limitations of microstrip patch antennas like narrow bandwidth and low gain. It then defines metamaterials and classifies them based on their permittivity and permeability values. Several types of metamaterials are described, including electromagnetic, negative index, single negative, photonic, tunable, terahertz, plasmonic, acoustic, nonlinear, and elastic metamaterials. Applications of metamaterial antennas are discussed, noting they can enhance radiated power and allow for electrically small antenna size, high directivity, and tunable frequency. Surface and volumetric artificial magnetic conductors are emphasized.
This document outlines a study exploring space radiation and its effects on biological matter. It describes the types of space radiation, the AE-8 and AP-8 radiation belt models from NASA, and simulation tools MULASSIS and Geant4. The document presents results from simulations of electron beam interactions with silicon and water samples of varying thicknesses. It concludes that exponential energy spectra have severe dose deposition effects and discusses further areas of investigation.
A wideband hybrid plasmonic fractal patch nanoantennIAEME Publication
This document proposes a wideband plasmonic optical fractal patch nanoantenna for use in intra-chip and inter-chip optical communications. The antenna is based on a hybrid plasmonic structure consisting of silver, silicon dioxide, and silicon. It operates over multiple optical bands from 1460-1625nm. The antenna design is iteratively modified using a rectangular tree-shaped fractal approach to increase its bandwidth. Simulation results show the second iteration design has an impedance bandwidth of around 38.5 THz, around 4 times greater than the initial design. The fractal antenna provides a gain up to 7.5dB and radiation efficiency of around 97% across the operating bandwidth.
A 2.98 dB NF, 2.52 mW Ultra-Wideband Low Noise Amplifier for a Brain Neuromod...SAKIB REZA
This work presents a low noise amplifier (LNA) for
lower ultrawideband (UWB) applications. The proposed LNA is
based on a current-reuse common source (CS) architecture so as
to achieve energy efficiency without sacrificing the noise
performance. With 1.2V supply voltage, the proposed LNA
consumes 2.52 mW power and achieves a 16.81 dB peak gain at 4.2
GHz frequency, with a 3-dB bandwidth of 1.28 GHz. The average
noise figure (NF) achieved is 2.98 dB over the 3-dB bandwidth. The
design is realized using a standard 0.18 µm CMOS process. The
characteristic of the proposed amplifier makes it a proper
candidate to be applied for implantable medical devices.
The Federal Communications Commission (FCC)
designated the 3.1-10.6 GHz frequency band for unlicensed
ultra-wideband (UWB) use back in 2002 promoting
commercial mass-market practices. UWB technology has
sparked substantial interest in both educational and commercial
enterprise because of its promise to provide high-speed shortrange wireless data transmission with considerable energy
efficiency.
UWB technology has shown promise for a number of
applications including Wireless Personal Area Networks
(WPAN) [1][2] and Wireless Sensor Networks [3]. UWB
communication uses the 3.1-10.6 GHz frequency spectrum
(lower band: 3.1-5 GHz; higher band: 6-10.6 GHz). The
development of the first generation UWB system will take
place in the low frequency range (3.1-5 GHz). When
considering time to market, hardware cost, degree of
complexity, and other factors, CMOS technology is a good
choice for implementing a low band UWB system [4]
Multiple channels are used to capture and transmit data in
high data rate biomedical applications such as neural signal
recording systems for brain-computer interface. The neural
recording system proposed in [9] uses a 128-channel system to
transfer the recorded brain signal at a data rate of 90 Mbps while
consuming only 6 mW of power. As the number of channels or
sample rate of the Analog to Digital Converter (ADC) increases,
so does the data rate. As such, the power consumption also
increases. As a result, it is critical to decrease power
consumption for such high data rate applications.
The novelty of this work is to design an energy-efficient
front-end amplifier exploiting 180 nm CMOS process which
enables the receiver chain to be operated in the UWB frequency
spectrum making it suitable for high data rate biomedical
applications. The design architecture of the proposed LNA is
discussed in section II. In section III, the simulation results are
provided followed by a concluding remark in section IV
The circuit diagram of the proposed LNA is shown in Fig.
1. It consists of four stages including input matching stage,
common source first stage, current reuse stage and the output
matching stage. The input matching network consists of the
capacitors C1 and C2 and the inductor L1 and L2. L2 is in series
resonance with the total capacitance connected to the gate
terminal of transistor MN1
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
This document provides a comprehensive review of the developments in antenna engineering from dipole antennas to fractal antennas. It begins with a brief introduction of antennas and their history, discussing various antenna types including dipole, loop, aperture, microstrip, reflector and more. It notes the problems faced in antenna design and the need for compact, multiband antennas. The review then focuses on the evolution of fractal antennas, which are more compact and exhibit multiband/wideband characteristics useful for wireless applications. Simulation methods like FDTD and FEM have been used to analyze fractal antenna performance in terms of parameters such as return loss, bandwidth and gain. The results from various papers are discussed and tabulated to better understand the progression of
Design and Analysis of Microstrip Patch Antenna with Optimization for Wireles...ijsrd.com
In this paper, design of conventional Rectangular patch Microstrip antenna has been proposed and its performance is analyzed. The design parameters of antenna are selected to achieve compact dimensions as well as best possible characteristics such as high gain, increased bandwidth with minimum return loss. Hence improved design has been demonstrated over elementary one. These antennas have been designed at 2.4GHz which enables its usage in wireless communication domain such as Wireless Local Area Network (WLAN). The antenna design and performance are analyzed using Ansoft HFSS software. These antennas can be used for many wireless communication systems.
The document reviews various methods for enhancing the bandwidth of microstrip patch antennas. It discusses how modifying the patch shape, using multilayer configurations, planar/stacked multi-resonator structures, and different feeding techniques can increase the antenna's bandwidth. Modified patch shapes, multilayer structures, and proximity coupled feeding provide the greatest bandwidth enhancements, with multilayer designs potentially achieving over 70% bandwidth. The review concludes that slot loading and multilayer techniques are most effective for enhancing bandwidth while maintaining a small antenna size.
The document summarizes modeling, simulation, and analysis of ultra-wideband (UWB) microstrip patch antennas. It provides an introduction to microstrip patch antennas and UWB technology. It then outlines the objectives of modeling and simulating UWB for microstrip patch antennas. Literary references are presented on UWB antenna designs. Advantages of microstrip patch antennas include low profile, easy integration with circuits, and versatility. Disadvantages include sensitivity to environment and low gain. Applications include mobile, satellite, and medical uses.
PRELIMINARY DESIGN AND CHARACTERISATION OF A NOVEL T-SHAPED NANO-ANTENNA ON D...jantjournal
The rapid growth of nanotechnology has led to the development of many devices with advanced characteristics such as high frequencies Gunn diodes, transistors, nano-antennas etc. Nano-antenna applications are numerous and encompass a variety of fields such as broadband communications, imaging, sensing, energy harvesting, and disease diagnosis. In this research paper, A novel T-shaped nano-antenna was designed and its resonant frequency was analysed. Moreover, parametric investigation had been performed to figure out the effects of T-shaped nano-antenna on Diamond Like Carbon (DLC) material. The momentum model in Advanced Design System (ADS) software was used to simulate the novel T-shaped nano-antenna and the results were directly compared to other nano-antennas. Initial results suggests that the T-shaped nano-antenna had a higher bandwidth and smaller geometrical size when compared to the other nano-antenna at Terahertz frequency.
PRELIMINARY DESIGN AND CHARACTERISATION OF A NOVEL T-SHAPED NANO-ANTENNA ON D...jantjournal
The rapid growth of nanotechnology has led to the development of many devices with advanced characteristics such as high frequencies Gunn diodes, transistors, nano-antennas etc. Nano-antenna applications are numerous and encompass a variety of fields such as broadband communications, imaging, sensing, energy harvesting, and disease diagnosis. In this research paper, A novel T-shaped nano-antenna was designed and its resonant frequency was analysed. Moreover, parametric investigation had been performed to figure out the effects of T-shaped nano-antenna on Diamond Like Carbon (DLC) material. The momentum model in Advanced Design System (ADS) software was used to simulate the novel T-shaped nano-antenna and the results were directly compared to other nano-antennas. Initial results suggests that the T-shaped nano-antenna had a higher bandwidth and smaller geometrical size when compared to the other nano-antenna at Terahertz frequency.
PRELIMINARY DESIGN AND CHARACTERISATION OF A NOVEL T-SHAPED NANO-ANTENNA ON D...jantjournal
The rapid growth of nanotechnology has led to the development of many devices with advanced characteristics such as high frequencies Gunn diodes, transistors, nano-antennas etc. Nano-antenna applications are numerous and encompass a variety of fields such as broadband communications, imaging, sensing, energy harvesting, and disease diagnosis. In this research paper, A novel T-shaped nano-antenna was designed and its resonant frequency was analysed. Moreover, parametric investigation had been performed to figure out the effects of T-shaped nano-antenna on Diamond Like Carbon (DLC) material. The momentum model in Advanced Design System (ADS) software was used to simulate the novel T-shaped nano-antenna and the results were directly compared to other nano-antennas. Initial results suggests that the T-shaped nano-antenna had a higher bandwidth and smaller geometrical size when compared to the other nano-antenna at Terahertz frequency.
PRELIMINARY DESIGN AND CHARACTERISATION OF A NOVEL T-SHAPED NANO-ANTENNA ON D...jantjournal
The rapid growth of nanotechnology has led to the development of many devices with advanced characteristics such as high frequencies Gunn diodes, transistors, nano-antennas etc. Nano-antenna applications are numerous and encompass a variety of fields such as broadband communications, imaging, sensing, energy harvesting, and disease diagnosis. In this research paper, A novel T-shaped nano-antenna was designed and its resonant frequency was analysed. Moreover, parametric investigation had been performed to figure out the effects of T-shaped nano-antenna on Diamond Like Carbon (DLC) material. The momentum model in Advanced Design System (ADS) software was used to simulate the novel T-shaped nano-antenna and the results were directly compared to other nano-antennas. Initial results suggests that the T-shaped nano-antenna had a higher bandwidth and smaller geometrical size when compared to the other nano-antenna at Terahertz frequency.
PRELIMINARY DESIGN AND CHARACTERISATION OF A NOVEL T-SHAPED NANO-ANTENNA ON D...jantjournal
This document summarizes the preliminary design and characterization of a novel T-shaped nano-antenna on diamond like carbon material. The T-shaped nano-antenna was designed and simulated using the momentum model in Advanced Design System software. Initial simulation results showed that the T-shaped nano-antenna had a higher bandwidth and smaller size compared to other nano-antennas at terahertz frequencies. Parametric analysis was performed to study the effects of varying the internal length and sectorial angle of the T-shaped nano-antenna on its resonant frequency and bandwidth.
PRELIMINARY DESIGN AND CHARACTERISATION OF A NOVEL T-SHAPED NANO-ANTENNA ON D...jantjournal
The rapid growth of nanotechnology has led to the development of many devices with advanced characteristics such as high frequencies Gunn diodes, transistors, nano-antennas etc. Nano-antenna applications are numerous and encompass a variety of fields such as broadband communications, imaging, sensing, energy harvesting, and disease diagnosis. In this research paper, A novel T-shaped nano-antenna was designed and its resonant frequency was analysed. Moreover, parametric investigation had been performed to figure out the effects of T-shaped nano-antenna on Diamond Like Carbon (DLC) material.
The momentum model in Advanced Design System (ADS) software was used to simulate the novel T-shaped nano-antenna and the results were directly compared to other nano-antennas. Initial results suggests that the T-shaped nano-antenna had a higher bandwidth and smaller geometrical size when compared to the other nano-antenna at Terahertz frequency.
PRELIMINARY DESIGN AND CHARACTERISATION OF A NOVEL T-SHAPED NANO-ANTENNA ON D...jantjournal
The rapid growth of nanotechnology has led to the development of many devices with advanced characteristics such as high frequencies Gunn diodes, transistors, nano-antennas etc. Nano-antenna applications are numerous and encompass a variety of fields such as broadband communications, imaging, sensing, energy harvesting, and disease diagnosis. In this research paper, A novel T-shaped nano-antenna was designed and its resonant frequency was analysed. Moreover, parametric investigation had been performed to figure out the effects of T-shaped nano-antenna on Diamond Like Carbon (DLC) material.
The momentum model in Advanced Design System (ADS) software was used to simulate the novel T-shaped nano-antenna and the results were directly compared to other nano-antennas. Initial results suggests that the T-shaped nano-antenna had a higher bandwidth and smaller geometrical size when compared to the other nano-antenna at Terahertz frequency.
Batteries -Introduction – Types of Batteries – discharging and charging of battery - characteristics of battery –battery rating- various tests on battery- – Primary battery: silver button cell- Secondary battery :Ni-Cd battery-modern battery: lithium ion battery-maintenance of batteries-choices of batteries for electric vehicle applications.
Fuel Cells: Introduction- importance and classification of fuel cells - description, principle, components, applications of fuel cells: H2-O2 fuel cell, alkaline fuel cell, molten carbonate fuel cell and direct methanol fuel cells.
This document summarizes a research paper that surveyed techniques used to enhance the performance of patch antennas using metamaterials. Metamaterials are artificially designed materials that can exhibit unusual electromagnetic properties not found in nature. They have been used in the last decade to design more compact and higher performance patch antennas for microwave applications. The document discusses various metamaterial-inspired patch antenna designs that have improved gain, directivity, bandwidth, side lobe suppression, and radiation efficiency. It also reviews the different types of metamaterials and how they provide solutions to challenges in conventional patch antenna design like small size and narrow bandwidth. In conclusion, it identifies open issues that could help guide future research in this area.
Review: Dual Band Microstrip Antennas for Wireless ApplicationsIJAAS Team
In this manuscript, a review of dual band microstrip antennas for wireless communication is presented. This review manuscript discusses regarding the geometric structures, different methods of analysis for antenna characteristics, and different types of wireless applications.
This document describes the design of a patch antenna that can operate at multiple frequency bands using metamaterials. A rectangular patch antenna is designed to operate at 3 GHz. Then, a unit cell of complementary split-ring resonator (CSRR) is designed to also operate at 3 GHz. An array of this CSRR unit cell is placed on the patch to act as a metamaterial and enable multiband operation. Specifically, the antenna is designed to resonate in the Bluetooth, WiMax and Wi-Fi bands. Simulation results using HFSS software show that the proposed antenna provides good performance in terms of voltage standing wave ratio, return loss and impedance matching for multiband operation.
Role of geometry of split ring resonators in magneticIAEME Publication
This document discusses the role of geometry in split ring resonators (SRRs) and magnetic resonance in metamaterials. It contains the following key points:
1) SRRs are the basic building blocks of metamaterials and allow control of magnetic response and negative permeability. Their geometry, including ring size, gap, spacing, substrate thickness, and material properties can be varied to control resonant frequency.
2) SRRs can be modeled as LC circuits, where the ring acts as an inductor and the gap as a capacitor. Resonant frequency depends inversely on size and dielectric properties.
3) Finite element method software is used to simulate SRR units and calculate effective permeability from scattering parameters
This document provides a review of metamaterials. It begins by discussing how metamaterials can overcome limitations of microstrip patch antennas like narrow bandwidth and low gain. It then defines metamaterials and classifies them based on their permittivity and permeability values. Several types of metamaterials are described, including electromagnetic, negative index, single negative, photonic, tunable, terahertz, plasmonic, acoustic, nonlinear, and elastic metamaterials. Applications of metamaterial antennas are discussed, noting they can enhance radiated power and allow for electrically small antenna size, high directivity, and tunable frequency. Surface and volumetric artificial magnetic conductors are emphasized.
This document outlines a study exploring space radiation and its effects on biological matter. It describes the types of space radiation, the AE-8 and AP-8 radiation belt models from NASA, and simulation tools MULASSIS and Geant4. The document presents results from simulations of electron beam interactions with silicon and water samples of varying thicknesses. It concludes that exponential energy spectra have severe dose deposition effects and discusses further areas of investigation.
A wideband hybrid plasmonic fractal patch nanoantennIAEME Publication
This document proposes a wideband plasmonic optical fractal patch nanoantenna for use in intra-chip and inter-chip optical communications. The antenna is based on a hybrid plasmonic structure consisting of silver, silicon dioxide, and silicon. It operates over multiple optical bands from 1460-1625nm. The antenna design is iteratively modified using a rectangular tree-shaped fractal approach to increase its bandwidth. Simulation results show the second iteration design has an impedance bandwidth of around 38.5 THz, around 4 times greater than the initial design. The fractal antenna provides a gain up to 7.5dB and radiation efficiency of around 97% across the operating bandwidth.
A 2.98 dB NF, 2.52 mW Ultra-Wideband Low Noise Amplifier for a Brain Neuromod...SAKIB REZA
This work presents a low noise amplifier (LNA) for
lower ultrawideband (UWB) applications. The proposed LNA is
based on a current-reuse common source (CS) architecture so as
to achieve energy efficiency without sacrificing the noise
performance. With 1.2V supply voltage, the proposed LNA
consumes 2.52 mW power and achieves a 16.81 dB peak gain at 4.2
GHz frequency, with a 3-dB bandwidth of 1.28 GHz. The average
noise figure (NF) achieved is 2.98 dB over the 3-dB bandwidth. The
design is realized using a standard 0.18 µm CMOS process. The
characteristic of the proposed amplifier makes it a proper
candidate to be applied for implantable medical devices.
The Federal Communications Commission (FCC)
designated the 3.1-10.6 GHz frequency band for unlicensed
ultra-wideband (UWB) use back in 2002 promoting
commercial mass-market practices. UWB technology has
sparked substantial interest in both educational and commercial
enterprise because of its promise to provide high-speed shortrange wireless data transmission with considerable energy
efficiency.
UWB technology has shown promise for a number of
applications including Wireless Personal Area Networks
(WPAN) [1][2] and Wireless Sensor Networks [3]. UWB
communication uses the 3.1-10.6 GHz frequency spectrum
(lower band: 3.1-5 GHz; higher band: 6-10.6 GHz). The
development of the first generation UWB system will take
place in the low frequency range (3.1-5 GHz). When
considering time to market, hardware cost, degree of
complexity, and other factors, CMOS technology is a good
choice for implementing a low band UWB system [4]
Multiple channels are used to capture and transmit data in
high data rate biomedical applications such as neural signal
recording systems for brain-computer interface. The neural
recording system proposed in [9] uses a 128-channel system to
transfer the recorded brain signal at a data rate of 90 Mbps while
consuming only 6 mW of power. As the number of channels or
sample rate of the Analog to Digital Converter (ADC) increases,
so does the data rate. As such, the power consumption also
increases. As a result, it is critical to decrease power
consumption for such high data rate applications.
The novelty of this work is to design an energy-efficient
front-end amplifier exploiting 180 nm CMOS process which
enables the receiver chain to be operated in the UWB frequency
spectrum making it suitable for high data rate biomedical
applications. The design architecture of the proposed LNA is
discussed in section II. In section III, the simulation results are
provided followed by a concluding remark in section IV
The circuit diagram of the proposed LNA is shown in Fig.
1. It consists of four stages including input matching stage,
common source first stage, current reuse stage and the output
matching stage. The input matching network consists of the
capacitors C1 and C2 and the inductor L1 and L2. L2 is in series
resonance with the total capacitance connected to the gate
terminal of transistor MN1
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
This document provides a comprehensive review of the developments in antenna engineering from dipole antennas to fractal antennas. It begins with a brief introduction of antennas and their history, discussing various antenna types including dipole, loop, aperture, microstrip, reflector and more. It notes the problems faced in antenna design and the need for compact, multiband antennas. The review then focuses on the evolution of fractal antennas, which are more compact and exhibit multiband/wideband characteristics useful for wireless applications. Simulation methods like FDTD and FEM have been used to analyze fractal antenna performance in terms of parameters such as return loss, bandwidth and gain. The results from various papers are discussed and tabulated to better understand the progression of
Design and Analysis of Microstrip Patch Antenna with Optimization for Wireles...ijsrd.com
In this paper, design of conventional Rectangular patch Microstrip antenna has been proposed and its performance is analyzed. The design parameters of antenna are selected to achieve compact dimensions as well as best possible characteristics such as high gain, increased bandwidth with minimum return loss. Hence improved design has been demonstrated over elementary one. These antennas have been designed at 2.4GHz which enables its usage in wireless communication domain such as Wireless Local Area Network (WLAN). The antenna design and performance are analyzed using Ansoft HFSS software. These antennas can be used for many wireless communication systems.
The document reviews various methods for enhancing the bandwidth of microstrip patch antennas. It discusses how modifying the patch shape, using multilayer configurations, planar/stacked multi-resonator structures, and different feeding techniques can increase the antenna's bandwidth. Modified patch shapes, multilayer structures, and proximity coupled feeding provide the greatest bandwidth enhancements, with multilayer designs potentially achieving over 70% bandwidth. The review concludes that slot loading and multilayer techniques are most effective for enhancing bandwidth while maintaining a small antenna size.
The document summarizes modeling, simulation, and analysis of ultra-wideband (UWB) microstrip patch antennas. It provides an introduction to microstrip patch antennas and UWB technology. It then outlines the objectives of modeling and simulating UWB for microstrip patch antennas. Literary references are presented on UWB antenna designs. Advantages of microstrip patch antennas include low profile, easy integration with circuits, and versatility. Disadvantages include sensitivity to environment and low gain. Applications include mobile, satellite, and medical uses.
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The rapid growth of nanotechnology has led to the development of many devices with advanced characteristics such as high frequencies Gunn diodes, transistors, nano-antennas etc. Nano-antenna applications are numerous and encompass a variety of fields such as broadband communications, imaging, sensing, energy harvesting, and disease diagnosis. In this research paper, A novel T-shaped nano-antenna was designed and its resonant frequency was analysed. Moreover, parametric investigation had been performed to figure out the effects of T-shaped nano-antenna on Diamond Like Carbon (DLC) material. The momentum model in Advanced Design System (ADS) software was used to simulate the novel T-shaped nano-antenna and the results were directly compared to other nano-antennas. Initial results suggests that the T-shaped nano-antenna had a higher bandwidth and smaller geometrical size when compared to the other nano-antenna at Terahertz frequency.
PRELIMINARY DESIGN AND CHARACTERISATION OF A NOVEL T-SHAPED NANO-ANTENNA ON D...jantjournal
The rapid growth of nanotechnology has led to the development of many devices with advanced characteristics such as high frequencies Gunn diodes, transistors, nano-antennas etc. Nano-antenna applications are numerous and encompass a variety of fields such as broadband communications, imaging, sensing, energy harvesting, and disease diagnosis. In this research paper, A novel T-shaped nano-antenna was designed and its resonant frequency was analysed. Moreover, parametric investigation had been performed to figure out the effects of T-shaped nano-antenna on Diamond Like Carbon (DLC) material. The momentum model in Advanced Design System (ADS) software was used to simulate the novel T-shaped nano-antenna and the results were directly compared to other nano-antennas. Initial results suggests that the T-shaped nano-antenna had a higher bandwidth and smaller geometrical size when compared to the other nano-antenna at Terahertz frequency.
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PRELIMINARY DESIGN AND CHARACTERISATION OF A NOVEL T-SHAPED NANO-ANTENNA ON D...jantjournal
The rapid growth of nanotechnology has led to the development of many devices with advanced characteristics such as high frequencies Gunn diodes, transistors, nano-antennas etc. Nano-antenna applications are numerous and encompass a variety of fields such as broadband communications, imaging, sensing, energy harvesting, and disease diagnosis. In this research paper, A novel T-shaped nano-antenna was designed and its resonant frequency was analysed. Moreover, parametric investigation had been performed to figure out the effects of T-shaped nano-antenna on Diamond Like Carbon (DLC) material. The momentum model in Advanced Design System (ADS) software was used to simulate the novel T-shaped nano-antenna and the results were directly compared to other nano-antennas. Initial results suggests that the T-shaped nano-antenna had a higher bandwidth and smaller geometrical size when compared to the other nano-antenna at Terahertz frequency.
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The momentum model in Advanced Design System (ADS) software was used to simulate the novel T-shaped nano-antenna and the results were directly compared to other nano-antennas. Initial results suggests that the T-shaped nano-antenna had a higher bandwidth and smaller geometrical size when compared to the other nano-antenna at Terahertz frequency.
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1. **Synchronous TDM**: In synchronous TDM, time slots are pre-assigned to each signal, regardless of whether the signal has data to transmit or not. This can lead to inefficiencies if some time slots remain empty due to the absence of data.
2. **Asynchronous TDM (or Statistical TDM)**: Asynchronous TDM addresses the inefficiencies of synchronous TDM by allocating time slots dynamically based on the presence of data. Time slots are assigned only when there is data to transmit, which optimizes the use of the communication channel.
### Applications of TDM
- **Telecommunications**: TDM is extensively used in telecommunication systems, such as in T1 and E1 lines, where multiple telephone calls are transmitted over a single line by assigning each call to a specific time slot.
- **Digital Audio and Video Broadcasting**: TDM is used in broadcasting systems to transmit multiple audio or video streams over a single channel, ensuring efficient use of bandwidth.
- **Computer Networks**: TDM is used in network protocols and systems to manage the transmission of data from multiple sources over a single network medium.
### Advantages of TDM
- **Efficient Use of Bandwidth**: TDM all
Manufacturing Process of molasses based distillery ppt.pptx
Phd proposal presentation
1. Properties of Multiple Microstrip Antennas
in Several Layers of Anisotropic Material
A Dissertation Proposal
By Benjamin Braaten
February 19, 2008
2. Outline
►Background
The microstrip antenna and mutual coupling
Previous work
►Proposed research
Research questions
Technical objectives and work plan
Initial work
►Significance of anticipated results
►Conclusion
2/25
3. Background
► Since Deschamps's [1] formal presentation of a microstrip
antenna in 1953 and detailed discussion by Alexopoulos
[2] there has been an extensive amount of research
devoted to the study of various printed antennas and
arrays.
► It is well known that printed antennas are [3]
very light
occupy a small volume
are useful at higher frequencies (f>1GHz)
provide a wide range of patterns
[1] G.A. Deschamps, “Microstrip Microwave Antennas,” 3rd USAF Symposium on Antennas, 1953.
[2] N.G. Alexopoulus, “Integrated-circuit structures on anisotropic substrates,” IEEE Transactions
on Microwave Theory and Techniques, Vol. 33, No. 10, October 1985, pp. 847-881.
[3] David M. Pozar and Daniel H. Schaubert, “Microstrip Antennas: The analysis and Design of
Microstrip Antennas and Arrays,” IEEE Press, Piscataway, NJ, 1995.
3/25
5. Background
► Region between
plates act like the
region between a
transmission line and
a ground plane with
both ends open.
► Results in standing
wave.
► Fringing fields are
responsible for
radiation.
5/25
6. Background
►Properties of interest include
Input impedance
Current distribution
Radiation patterns
Band-width
Feed techniques
Mutual impedance with other elements
Conducting patch layout … etc.
6/25
7. Previous work-isolated antennas
► In 1979 a significant step was
taken by Uzunoglu,
Alexopoulos and Fikioris [9]
microstrip dipoles
radiation propoerties
Based on Green’s function for
a hertizian dipole over a
grounded isotropic substrate
► Working from that base, Rana
and Alexopoulos presented
work in 1981 on the current
distribution and input
impedance of printed dipoles
[10].
[9] N.K. Uzunoglu, N.G. Alexopoulos and J.G. Fikioris, “Radiation properties of microstrip dipoles,'‘
IEEE Transactions on Antennas and Propagation, Vol. 27, No. 6, November 1979, pp. 853-858.
[10] I.E. Rana and N.G. Alexopoulos, “Current distribution and input impedance of printed dipoles,”
IEEE Transactions on Antennas and Propagation, Vol. 29, No. 1, January 1981, pp. 99-105.
7/25
8. Previous work-isolated antennas
► The above work with Green's functions in the spectral form laid the
foundation for future work by Pozar [11] and others to analyze
properties of other various microstrip antennas.
► In parallel with the development by Alexopoulos and his colleagues, in
1980 and 1981, Itoh and Mentzel [12]-[13] developed a spectral
domain immittance approach.
► This lead to the work by Lee and Tripathi [15] and later Nelson, Rogers
and d’Assuncao [16] to study layered anisotropic structures.
[11] D.M. Pozar, “Input impedance and mutual coupling of rectangular microstrip antennas,”
IEEE Transactions on Antennas and Propagation, Vol. 30, No. 6, November 1982, pp. 1191-1196.
[12] T. Itoh, “Spectral domain immitance approach for dispersion characteristics of generalized printed
transmission lines,” IEEE Transactions on Antennas and Propagation, Vol. 28, No. 7, July 1980, pp. 733-736.
[13] T. Itoh and W. Menzel, “A full-wave analysis method for open microstrip structures,”
IEEE Transactions on Microwave Theory and Techniques, Vol. 29, No. 1, January 1981, pp. 63-68.
[15] H. Lee and V.K. Tripathi, “Spectral domain analysis of frequency dependent propagation characteristics
of planar structures on uniaxial medium,” IEEE Transactions on Microwave Theory and Techniques, Vol.
30, No. 8, August 1982, pp. 1188-1193.
[16] R.M. Nelson, D.A. Rogers and A.G. D'Assuncao, “Resonant frequency of a rectangular microstrip patch
on several uniaxial substrates,” IEEE Transactions on Antennas and Propagation, Vol. 38, No. 7,
July 1990, pp. 973-981. 8/25
9. Previous work-mutual coupling
► In 1981, Alexopoulos and Rana [22] study the mutual
impedance between printed dipoles (Green’s function in
spectral form)
► Then in 1982, Pozar
presents the mututal
impedance between
rectangular microstrip
antennas [11]
[22] N.G. Alexopoulos and I.E. Rana, “Mutual impedance computation between printed dipoles,”
IEEE Transactions on Antennas and Propagation, Vol. 29, No. 1, January 1981, pp. 106-112.
[11] D.M. Pozar, “Input impedance and mutual coupling of rectangular microstrip antennas,”
IEEE Transactions on Antennas and Propagation, Vol. 30, No. 6, November 1982, pp. 1191-1196.
9/25
10. Current work
► In 1998, Waterhouse, Targonski and Kokotoff [36]
discuss the design and performance of using shorting
posts on a microstrip patch antenna on an isotropic
substrate.
► In 2001, Verma and Nisimuddin [34] investigate the
input impedance of rectangular microstrip antennas
Different from work by Oliveira and d’Assuncao [20]
[36] R.B. Waterhouse, S.D. Targonski and D.M. Kokotoff, “Design and performance of small printed
antennas,” IEEE Transactions on Antennas and Propagation, Vol. 46, No. 11, November 1998.
[20] J.R.S. Oliveira and A.G. D'Assuncao, “Input impedance of microstrip patch antennas on anisotropic
dielectric substrates,” Antennas and Propagation Society International Symposium, 1996. AP-S. Digest,
Vol. 2, July 21-26, 1996, p. 1066-1069.
[34] A.K. Verma and Nasimuddin, “Input impedance of rectangular microstrip patch antenna with
iso/anisotropic substrate-superstrate,'‘ IEEE Microwave and Wireless Components Letters, Vol. 11, No. 11,
November 2001, pp. 456-458.
10/25
11. Current work
► Also in 2001, Shackelford,
Lee, Chatterjee, Guo, Luk
and Chair [39] present a
small-sized wide-band U-
slot and L-probe fed
microstrip antenna with
shorting walls.
[34] A. Shackelford, K.F. Lee, D. Chatterjee, Y.X. Guo,
K.M. Luk and R. Chair, “Small-size wide-bandwidth
microstrip patch antennas,” IEEE Antennas and
Propagation Society International Symposium, 2001,
Vol. 1, July 8-13, 2001, pp. 86-89.
11/25
12. Current work
► In 2003 Yang and Samii [48] presented a low mutual coupling design
of an array of electromagnetic band gap structures.
Used FDTD
Single anisotropic substrate
► In 2005 Chair, Kishk and Lee [49] presented work on the mutual
coupling between a 2 element array of circular patch antennas.
Used IE3D [44]
Single isotropic substrate on an isotropic dielectric substrate.
► Then, in 2007, Buell, Mosallaei and Sarabandi [45] used metamaterial
to suppress the mutual coupling between elements in a densely packed
array.
metamaterial as isolation walls between the elements.
[48] F. Yang and Y. Rahmatt-Samii “Microstrip antennas integrated with electromagnetic band-gap
(EBG) structures: a low mutual coupling design for array applications,'‘ IEEE Transactions on Antennas
and Propagation, Vol. 51, No. 10, October 2003, pp. 2936-2946.
[49] R. Chair, A.A. Kishk and K-F. Lee, “Comparative study on the mutual coupling between different
sized cylindrical dielectric resonators antennas and circular microstrip patch antennas,” IEEE Transactions
on Antennas and Propagation, Vol. 53, No. 3, March 2005, pp. 1011-1019.
[44] www.zeland.com.
[45] K. Buell, H. Mosallaei and K. Sarabandi, “Metamaterial insulator enabled superdirective array,”
IEEE Transactions on Antennas and Propagation, Vol. 55, No. 4, April 2007, 1074-1085. 12/25
14. Proposed research
RESEARCH QUESTIONS:
► What is the input impedance of a driven element in the
layered anisotropic structure in the presence of other
conducting patches defined on arbitrary anisotropic layers
in the same structure?
and
► What is the mutual impedance between a driven element
in the layered anisotropic structure and other conducting
patches defined on arbitrary anisotropic layers in the same
structure?
14/25
15. Proposed research
The previous two questions are very
significant in many fields.
Microstrip antenna arrays [3].
Frequency Selective Structures (FSS) [53]
Radio Frequency Identification (RFID) [56]
[3] David M. Pozar and Daniel H. Schaubert, “Microstrip Antennas: The analysis and Design of
Microstrip Antennas and Arrays”, IEEE Press, Piscataway, NJ, 1995.
[53] A.L.P.S. Campos an A.G. d'Assuncao, “Scattering paramters of a frequnecy selective surface
between anisotropic dielectric layers for incidnet co-polarized plane waves,” IEEE Antennas and
Propagation Society International Symposium, 2001, Vol. 4, July 8-13, 2001, p. 382-385.
[56] K. Finkenzeller, RFID Handbook:Fundamentals and Applications in Contactless Smart Cards
and Identification, John Wiley and Sons, West Sussex, England, 2003.
15/25
16. Technical Objectives
► Choose the appropriate types of microstrip
antennas that will allow the work to proceed to
answer the proposed questions.
► Choose and develop the numerical technique that
can be used to compute the input impedance and
mutual coupling between elements in the
anisotropic structure.
► Validate numerical results for the isotropic case
with commercially available software.
► Design and build a multiple layered structure to
measure and validate the numerical calculations of
input impedance and mutual coupling.
16/25
17. Work Plan
► Choose the appropriate types of microstrip
antennas that will allow the work to proceed to
answer the proposed questions.
Printed dipoles by Alexopoulos and Rana [10]
Rectangular microstrip antennas by Nelson [16], Pozar
[19], and Oliveira [20].
UWB
[10] I.E. Rana and N.G. Alexopoulos, “Current distribution and input impedance of printed dipoles,”
IEEE Transactions on Antennas and Propagation, Vol. 29, No. 1, January 1981, pp. 99-105.
[16] R.M. Nelson, D.A. Rogers and A.G. D'Assuncao, “Resonant frequency of a rectangular microstrip patch
on several uniaxial substrates,” IEEE Transactions on Antennas and Propagation, Vol. 38, No. 7,
July 1990, pp. 973-981.
[19] D.M. Pozar, “Radiation and scattering from a microstrip patch on a uniaxial substrate,” IEEE
Transactions on Antennas and Propagation, Vol. 35, No. 6, June 1987, pp. 613-621.
[20] J.R.S. Oliveira and A.G. D'Assuncao, “Input impedance of microstrip patch antennas on anisotropic
dielectric substrates,” Antennas and Propagation Society International Symposium, 1996. AP-S. Digest,
Vol. 2, July 21-26, 1996, p. 1066-1069. 17/25
18. Work Plan
► Choose and develop the numerical technique that can be used to
compute the input impedance and mutual coupling between elements
in the anisotropic structure.
Exact Green’s function [11, Pozar]
► Numerical integration and derivatives are extensive
► Developed to evaluate problems with anisotropic material
► Developed to evaluate problems with multiple anisotropic layers
Equivalent magnetic source [30, Benalla]
► Field expression are much simpler
► Numerical integration and derivatives are extensive
► Needs to be extended to evaluate the problems proposed here
Spectral domain immittance method [16, Nelson]
► Derivation is lengthy
► Needs to be developed to compute mutual impedance
► Numerical integration is nice
► No derivative approximations
► Developed to evaluate problems with multiple anisotropic materials
18/25
19. Work Plan
►Validate numerical results for the isotropic
case with commercially available software.
Use Momentum in Advanced Design System
(ADS) [64].
Reproduce printed dipole work by Rana and
Alexopoulos [22].
Reproduce rectangular microstrip results by
Pozar [11].
[22] N.G. Alexopoulos and I.E. Rana, “Mutual impedance computation between printed dipoles,”
IEEE Transactions on Antennas and Propagation, Vol. 29, No. 1, January 1981, pp. 106-112.
[11] D.M. Pozar, “Input impedance and mutual coupling of rectangular microstrip antennas,”
IEEE Transactions on Antennas and Propagation, Vol. 30, No. 6, November 1982, pp. 1191-1196.
[64] www.agilent.com.
19/25
20. Work Plan
Many significant results will be obtained by
looking at the previous problems in
Momentum:
The problems will validate the numerically
extensive code using the spectral domain
immittance method
The new code can be used for multiple patch
geometries
Momentum can be used as a good tool in this
type of research
20/25
21. Work Plan
► Design and build a multiple
layered structure to
measure and validate the
numerical calculations of
input impedance and
mutual coupling.
Jadlecka, Poe and Carver
[24] – measurement
technique
Validates code with
measurements
[24] R.P. Jedlicka, M.T. Poe and K.R. Carver,
“Measured mutual coupling between microstrip
antennas,” IEEE Transactions on Antennas
and Propagation, Vol. 29, No. 1, January 1981.
21/25
22. Initial work
►Derivation of the immittance functions for
the single layer isotropic case
►Polar and rectangular integration of the
immittance functions have been started and
compare well with Nelson’s Fortran results
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23. Significance of anticipated results
► Mutual impedance will significantly effect input impedance
of driven elements
► Appropriate values of permittivity could possibly minimize
mutual impedance (Krowne [17] and Wang [62])
► Possible reduction of array surface area
Values of permittivity
Conducting surface on multiple layers
► UWB antennas
► 60GHz-90GHz band
► Dual frequency antennas
► RFID systems
[17] C.M. Krowne, “Green's function in the spectral domain for biaxial and uniaxial anisotropic planar
dielectric structures,” IEEE Transactions on Antennas and Propagation, Vol. 32, No. 12, December 1984.
[62] W.J. Wang, “Multilayered printed antennas with biaxial anisotropic dielectric substrates:
general analysis and case studies,” Ph.D. Dissertation, Polytechnic University, January 2002.
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24. Conclusion
► A method for investigating the input impedance
and mutual coupling of multiple microstrip
antennas on multiple anisotropic layers is
presented.
► Based on the spectral domain immittance method
► Areas of interest include
RFID
Microstrip arrays – UWB, dual frequncy, … .etc
EMC
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