This document provides information about RF and microwave engineering:
1. It defines radio frequency as any electromagnetic wave frequency between 3KHz to 300GHz, which includes frequencies used for communications and radar signals. Microwaves are defined as electromagnetic waves between 300MHz to 300GHz.
2. Microwave engineering deals with the design of communication, navigation, and other systems that operate in the microwave frequency range. Key applications discussed include microwave ovens, radar, satellite communication, and TV.
3. Analysis of microwave circuits differs from low frequency circuits as the physical length of components is larger than signal wavelengths. S-parameters are used to relate the amplitude of scattered waves to incident waves in microwave circuit analysis.
An antenna converts radio frequency electric current into electromagnetic waves that are radiated into space. The same antenna can transmit and receive signals. Key antenna concepts include reciprocity, radiation patterns, gain, and polarization. Antenna gain compares its power output to an isotropic antenna. Common antennas include dipole, parabolic reflective, and types are optimized for propagation modes like ground wave, sky wave, and line-of-sight. Signal strength is reduced by factors like free space loss, noise, multipath, and fading over the transmission path.
A Klystron is a vacuum tube that can be used either as a generator or as an amplifier or as an oscillator, at microwave frequencies.The Klystron is a linear beam device; that is, the electron flow is in a straight line focused by an axial magnetic field.
MicroStrip Antenna
Introduction .
Micro-Strip Antennas Types .
Micro-Strip Antennas Shapes .
Types of Substrates (Dielectric Media) .
Comparison of various types of flat profile printed antennas .
Advantages & DisAdvantages of MSAs .
Applications of MSAs .
Radiation patterns of MSAs .
How to Optimizing the Substrate Properties for Increased Bandwidth ?
Comparing the different feed techniques .
Ground waves propagate along the Earth's surface and are used for medium wave (MW) transmissions. Space waves travel in straight lines but are limited by the curvature of the Earth. Sky waves are used for short wave (SW) transmissions and reflect off the ionosphere which consists of layers (D, E, F1, F2) that vary in density and thickness depending on the time of day and sun exposure. Different propagation modes are used depending on the frequency band and conditions to maximize transmission range.
This document provides information on fundamental antenna parameters and concepts. It discusses:
1. How antennas convert guided waves into radiating waves and vice versa.
2. Key antenna parameters including radiation pattern, directivity, radiation resistance, efficiency, gain, bandwidth, reciprocity, effective aperture, beamwidth, and polarization matching.
3. The Friis transmission formula for calculating received power between two antennas in free space based on their gains, wavelength, and distance.
Broadside Array vs end-fire array
Higher directivity.
Provide increased directivity in
elevation and azimuth planes.
Generally used for reception.
Impedance match difficulty in
high power transmissions.
Variants are:
Horizontal Array of Dipoles
RCA Fishborne Antenna
Series Phase Array
Space wave propagation involves radio waves that travel directly or after reflecting off the Earth's surface within the lower 20 km of the atmosphere. These waves can propagate line-of-sight between transmitter and receiver antennas in the VHF and UHF bands. Space waves follow two paths - direct or ground reflected - and may arrive in or out of phase, causing signal fluctuations. The maximum transmission distance is limited by the Earth's curvature and obstructions that can cause shadowing effects. Refractive phenomena like super-refraction can sometimes extend the radio horizon.
This document provides an overview of microwave tubes, including their components and operating principles. It discusses cavity resonators, rectangular cavity resonators, limitations of conventional vacuum tubes at high frequencies, and types of microwave tubes like klystrons, traveling wave tubes (TWTs), and magnetrons. Magnetrons are used in microwave ovens and produce hundreds of watts of microwave power by directing an electron beam in a circular pattern using a strong magnetic field. TWTs amplify signals in the microwave frequency range from 500 MHz to 300 GHz using an electron beam interacting with a slow-wave structure.
An antenna converts radio frequency electric current into electromagnetic waves that are radiated into space. The same antenna can transmit and receive signals. Key antenna concepts include reciprocity, radiation patterns, gain, and polarization. Antenna gain compares its power output to an isotropic antenna. Common antennas include dipole, parabolic reflective, and types are optimized for propagation modes like ground wave, sky wave, and line-of-sight. Signal strength is reduced by factors like free space loss, noise, multipath, and fading over the transmission path.
A Klystron is a vacuum tube that can be used either as a generator or as an amplifier or as an oscillator, at microwave frequencies.The Klystron is a linear beam device; that is, the electron flow is in a straight line focused by an axial magnetic field.
MicroStrip Antenna
Introduction .
Micro-Strip Antennas Types .
Micro-Strip Antennas Shapes .
Types of Substrates (Dielectric Media) .
Comparison of various types of flat profile printed antennas .
Advantages & DisAdvantages of MSAs .
Applications of MSAs .
Radiation patterns of MSAs .
How to Optimizing the Substrate Properties for Increased Bandwidth ?
Comparing the different feed techniques .
Ground waves propagate along the Earth's surface and are used for medium wave (MW) transmissions. Space waves travel in straight lines but are limited by the curvature of the Earth. Sky waves are used for short wave (SW) transmissions and reflect off the ionosphere which consists of layers (D, E, F1, F2) that vary in density and thickness depending on the time of day and sun exposure. Different propagation modes are used depending on the frequency band and conditions to maximize transmission range.
This document provides information on fundamental antenna parameters and concepts. It discusses:
1. How antennas convert guided waves into radiating waves and vice versa.
2. Key antenna parameters including radiation pattern, directivity, radiation resistance, efficiency, gain, bandwidth, reciprocity, effective aperture, beamwidth, and polarization matching.
3. The Friis transmission formula for calculating received power between two antennas in free space based on their gains, wavelength, and distance.
Broadside Array vs end-fire array
Higher directivity.
Provide increased directivity in
elevation and azimuth planes.
Generally used for reception.
Impedance match difficulty in
high power transmissions.
Variants are:
Horizontal Array of Dipoles
RCA Fishborne Antenna
Series Phase Array
Space wave propagation involves radio waves that travel directly or after reflecting off the Earth's surface within the lower 20 km of the atmosphere. These waves can propagate line-of-sight between transmitter and receiver antennas in the VHF and UHF bands. Space waves follow two paths - direct or ground reflected - and may arrive in or out of phase, causing signal fluctuations. The maximum transmission distance is limited by the Earth's curvature and obstructions that can cause shadowing effects. Refractive phenomena like super-refraction can sometimes extend the radio horizon.
This document provides an overview of microwave tubes, including their components and operating principles. It discusses cavity resonators, rectangular cavity resonators, limitations of conventional vacuum tubes at high frequencies, and types of microwave tubes like klystrons, traveling wave tubes (TWTs), and magnetrons. Magnetrons are used in microwave ovens and produce hundreds of watts of microwave power by directing an electron beam in a circular pattern using a strong magnetic field. TWTs amplify signals in the microwave frequency range from 500 MHz to 300 GHz using an electron beam interacting with a slow-wave structure.
Fundamentals of microwave communication system and radar systemssabesh chaudhary
This presentation educates about the basics of microwave engineerinng and RADAR engineering which must be valuable for the students of Engineering (EEE, ECE Aeronautical Engg. etc) to get the insight of related subjects.
This document discusses various digital modulation techniques. It begins by defining modulation as adding information to a carrier signal. It then distinguishes between analog and digital modulation. Digital modulation modulates an analog carrier signal with a discrete signal, and can be considered as converting digital-to-analog and vice versa. Some key digital modulation techniques discussed include amplitude shift keying (ASK), frequency shift keying (FSK), phase shift keying (PSK), quadrature amplitude modulation (QAM), and differential phase shift keying (DPSK). Metrics for comparing digital modulation techniques include power efficiency, bandwidth efficiency, and implementation cost-effectiveness.
The document summarizes key components and concepts in basic microwave engineering. It discusses waveguides and their operating frequencies based on dimensions. It also describes electric and magnetic fields in rectangular waveguides. Additional components summarized include coaxial to waveguide transitions, choke joints, coupling loops, phase shifters, junctions, tuners, mixers, isolators, circulators, directional couplers, and cavity resonators. Isolators, circulators, and directional couplers are multi-port devices that control the direction of signal propagation with differing levels of attenuation.
The document discusses the TRAPATT diode, which is a type of p-n junction diode that generates microwaves. It operates by forming a trapped plasma within the junction region when a high electric field propagates through. Key points:
- It was first reported in 1967 and can generate power over 1 kW at frequencies up to 50 GHz with efficiencies up to 75%
- It operates by inducing avalanche breakdown to generate a dense plasma of electrons and holes within the depletion region, which becomes trapped and oscillates the voltage and current
- Applications include low power Doppler radars, radio altimeters, and radar transmitters due to its pulsed operation capabilities between 3-50 GHz
This document provides an overview of satellite communication link design. It discusses basic transmission theory including the link equation and factors that affect received power such as EIRP, path loss, and antenna gains. It also covers system noise temperature and the G/T ratio. The document outlines considerations for designing downlinks and uplinks. It describes how to calculate overall C/N ratio when multiple C/N ratios are present in the link. Finally, it lists the typical steps involved in designing a satellite communication link for a specified C/N requirement.
The document discusses the basics of microwaves and radar technology. It begins with an introduction to microwaves, including their properties, advantages, disadvantages and applications. It then covers topics such as waveguides, how microwave ovens work, and the basic principles and functions of radar systems. The document provides information on different microwave frequency bands, wave propagation in waveguides, and common uses of radar technology in fields like weather monitoring, air traffic control and law enforcement.
An antenna converts electric energy to radio waves and vice versa. It consists of a transmitter and receiver. There are different types of antennas including Yagi-Uda antennas, helix antennas, parabolic antennas, loop antennas, and horn antennas. Each antenna type has distinct characteristics like directionality, frequency range, and applications. For example, Yagi-Uda antennas have high gain and directivity for frequencies from 300MHz to 3GHz, while helix antennas are omni-directional for VHF and UHF bands.
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The document discusses various topics related to radio wave propagation. It covers the different types of propagation including ground wave, space wave, and sky wave. It describes line of sight propagation and how increasing antenna height allows communication over longer distances. Tropospheric propagation is discussed along with how turbulence in the troposphere can scatter radio waves. The document also covers polarization of radio waves for different propagation types and the advantages of horizontal and vertical polarization. Finally, it defines attenuation and provides examples of attenuation levels through common materials.
Coherent and Non-coherent detection of ASK, FSK AND QASKnaimish12
This document discusses different digital communication techniques including coherent and non-coherent detection methods for amplitude shift keying (ASK), frequency shift keying (FSK) and quadrature amplitude shift keying (QASK). Coherent detection requires a reference carrier wave and exploits phase information, while non-coherent detection does not require a reference wave. It then describes the receiver designs for coherent and non-coherent detection of ASK and FSK. For QASK, it outlines raising the input signal to the fourth power before bandpass filtering and frequency division to recover the transmitted bit sequence.
A loop antenna is a radio antenna consisting of a loop or coil of wire, tubing, or other electrical conductor with its ends connected to a balanced transmission line (or possibly a balun). There are two distinct antenna designs: the small loop (or magnetic loop) with a size much smaller than a wavelength, and the much larger resonant loop antenna with a circumference close to the intended wavelength of operation. Small loops have low radiation resistance and thus poor efficiency and are mainly used as receiving antennas at low frequencies. To increase the magnetic field in the loop and thus the efficiency, the coil of wire is often wound around a ferrite rod magnetic core; this is called a ferrite loop antenna. The ferrite loop is the antenna used in many AM broadcast receivers, with the exception of external loops used with AV Amplifier-Receivers and car radios; the antenna is often contained inside the radio's case. These antennas are also used for radio direction finding. In amateur radio, loop antennas are often used for low profile operating where larger antennas would be inconvenient, unsightly.
(c) WIkipedia
1. Digital modulation techniques are used to modulate digital information so that it can be transmitted via different mediums. Common digital modulation methods include binary amplitude shift keying (ASK), frequency shift keying (FSK), and phase shift keying (PSK).
2. FSK conveys information by changing the instantaneous frequency of a carrier wave. It is less susceptible to errors than ASK but has a larger spectrum bandwidth. PSK varies the phase of the transmitted signal. BPSK uses two phases while QPSK uses four phases.
3. The performance of digital modulation techniques can be compared using the energy per bit to noise power spectral density ratio (Eb/N0). Lower Eb/N0 values
The document discusses the Yagi-Uda antenna, which consists of multiple parallel dipole elements including a reflector, driven element, and multiple directors. It operates in the HF to UHF bands and provides a directional radiation pattern with moderate gain. Key advantages are its directionality and ability to operate at high frequencies. Common applications include television reception and radar systems where its directional properties and moderate gain are beneficial.
This document discusses various microwave measurement techniques, including:
- Power, VSWR, impedance, frequency, cavity Q, and wavelength measurements.
- Common measurement devices are vector network analyzers, spectrum analyzers, power meters, tunable detectors, slotted sections, and VSWR meters.
- Power is typically measured using diode detectors, bolometers, or thermocouples, which convert RF power to a measurable DC signal.
Microwave engineering involves the design of communication and navigation systems that operate in the microwave frequency range. Key topics in microwave engineering include microwave networks, scattering parameters, power dividers, couplers, filters, and amplifiers. Microwave systems have applications in areas like microwave ovens, radar, satellite communications, and personal communication systems.
This document discusses amplitude modulation (AM) as a type of modulation used to transmit information signals. Modulation involves varying a high frequency carrier signal by an information signal in order to transmit the information signal over long distances. In AM, the amplitude of the carrier signal is varied in accordance with the instantaneous amplitude of the modulating or information signal. This creates two new sideband frequencies above and below the carrier frequency equal to the modulation frequency. The carrier and sidebands together make up the modulated signal. Only a portion of the transmitted power is present in the sidebands containing the information, while the rest is wasted in the carrier.
This document discusses microwave devices, specifically directional couplers and isolators. It begins by defining microwaves and their applications such as telecommunications and radar. It then describes how directional couplers are passive devices that divide power through four ports and discusses their key figures of merit like coupling factor, isolation, and directivity. Isolators are also covered as two-port non-reciprocal devices that allow high power transmission in one direction while providing high attenuation in the opposite direction using Faraday rotation in a ferrite rod.
A horn antenna or microwave horn is an antenna that consists of a flaring metal waveguide shaped like a horn to direct radio waves in a beam. Horns are widely used as antennas at UHF and microwave frequencies, above 300 MHz.
This document discusses various digital modulation techniques including:
- Amplitude Shift Keying (ASK) which represents data as changes in signal amplitude.
- Frequency Shift Keying (FSK) which represents data as changes in carrier frequency.
- Phase Shift Keying (PSK) which represents data as changes in the phase of the carrier signal.
- Minimum Shift Keying (MSK) and Gaussian Minimum Shift Keying (GMSK) which are continuous phase modulation schemes used in wireless communications for their spectral efficiency.
- Quadrature Amplitude Modulation (QAM) which combines ASK and PSK to send multiple bits per symbol.
Ground wave propagation, Sky wave propagation, Space Wave propagation, Multi hop propagation, Duct wave propagation, LOS propagation, Ionospheric Layers
Network analysis of rf and microwave circuitsShankar Gangaju
This document discusses microwave network analysis and two-port network analysis. It begins by defining a microwave network as consisting of microwave devices and components coupled by transmission lines. It then discusses that at microwave frequencies, circuit analysis techniques like KCL and KVL cannot be used and S-parameters provide an alternative. The document defines S-parameters as a way to characterize networks using normalized power waves rather than voltages and currents. It provides properties and definitions of S-parameters for two-port networks, including what S11, S12, S21, and S22 represent. It also discusses uses of S-parameters and scattering matrices for modeling networks.
1. The document discusses microwave communication and components. It defines microwaves as electromagnetic waves with frequencies between 1GHz and 300GHz.
2. It describes various microwave frequency bands and their applications. Key applications discussed include wireless communications, radar, satellite communications and medical applications like cancer treatment and imaging.
3. Microwave components discussed include transmission lines, isolators, circulators, and E-plane tee junctions. Their properties and S-parameter matrices are defined. Microwave network parameters like Z, Y, H and ABCD are also introduced but it is noted they are not suitable for microwave frequencies.
Fundamentals of microwave communication system and radar systemssabesh chaudhary
This presentation educates about the basics of microwave engineerinng and RADAR engineering which must be valuable for the students of Engineering (EEE, ECE Aeronautical Engg. etc) to get the insight of related subjects.
This document discusses various digital modulation techniques. It begins by defining modulation as adding information to a carrier signal. It then distinguishes between analog and digital modulation. Digital modulation modulates an analog carrier signal with a discrete signal, and can be considered as converting digital-to-analog and vice versa. Some key digital modulation techniques discussed include amplitude shift keying (ASK), frequency shift keying (FSK), phase shift keying (PSK), quadrature amplitude modulation (QAM), and differential phase shift keying (DPSK). Metrics for comparing digital modulation techniques include power efficiency, bandwidth efficiency, and implementation cost-effectiveness.
The document summarizes key components and concepts in basic microwave engineering. It discusses waveguides and their operating frequencies based on dimensions. It also describes electric and magnetic fields in rectangular waveguides. Additional components summarized include coaxial to waveguide transitions, choke joints, coupling loops, phase shifters, junctions, tuners, mixers, isolators, circulators, directional couplers, and cavity resonators. Isolators, circulators, and directional couplers are multi-port devices that control the direction of signal propagation with differing levels of attenuation.
The document discusses the TRAPATT diode, which is a type of p-n junction diode that generates microwaves. It operates by forming a trapped plasma within the junction region when a high electric field propagates through. Key points:
- It was first reported in 1967 and can generate power over 1 kW at frequencies up to 50 GHz with efficiencies up to 75%
- It operates by inducing avalanche breakdown to generate a dense plasma of electrons and holes within the depletion region, which becomes trapped and oscillates the voltage and current
- Applications include low power Doppler radars, radio altimeters, and radar transmitters due to its pulsed operation capabilities between 3-50 GHz
This document provides an overview of satellite communication link design. It discusses basic transmission theory including the link equation and factors that affect received power such as EIRP, path loss, and antenna gains. It also covers system noise temperature and the G/T ratio. The document outlines considerations for designing downlinks and uplinks. It describes how to calculate overall C/N ratio when multiple C/N ratios are present in the link. Finally, it lists the typical steps involved in designing a satellite communication link for a specified C/N requirement.
The document discusses the basics of microwaves and radar technology. It begins with an introduction to microwaves, including their properties, advantages, disadvantages and applications. It then covers topics such as waveguides, how microwave ovens work, and the basic principles and functions of radar systems. The document provides information on different microwave frequency bands, wave propagation in waveguides, and common uses of radar technology in fields like weather monitoring, air traffic control and law enforcement.
An antenna converts electric energy to radio waves and vice versa. It consists of a transmitter and receiver. There are different types of antennas including Yagi-Uda antennas, helix antennas, parabolic antennas, loop antennas, and horn antennas. Each antenna type has distinct characteristics like directionality, frequency range, and applications. For example, Yagi-Uda antennas have high gain and directivity for frequencies from 300MHz to 3GHz, while helix antennas are omni-directional for VHF and UHF bands.
FellowBuddy.com is an innovative platform that brings students together to share notes, exam papers, study guides, project reports and presentation for upcoming exams.
We connect Students who have an understanding of course material with Students who need help.
Benefits:-
# Students can catch up on notes they missed because of an absence.
# Underachievers can find peer developed notes that break down lecture and study material in a way that they can understand
# Students can earn better grades, save time and study effectively
Our Vision & Mission – Simplifying Students Life
Our Belief – “The great breakthrough in your life comes when you realize it, that you can learn anything you need to learn; to accomplish any goal that you have set for yourself. This means there are no limits on what you can be, have or do.”
Like Us - https://www.facebook.com/FellowBuddycom
The document discusses various topics related to radio wave propagation. It covers the different types of propagation including ground wave, space wave, and sky wave. It describes line of sight propagation and how increasing antenna height allows communication over longer distances. Tropospheric propagation is discussed along with how turbulence in the troposphere can scatter radio waves. The document also covers polarization of radio waves for different propagation types and the advantages of horizontal and vertical polarization. Finally, it defines attenuation and provides examples of attenuation levels through common materials.
Coherent and Non-coherent detection of ASK, FSK AND QASKnaimish12
This document discusses different digital communication techniques including coherent and non-coherent detection methods for amplitude shift keying (ASK), frequency shift keying (FSK) and quadrature amplitude shift keying (QASK). Coherent detection requires a reference carrier wave and exploits phase information, while non-coherent detection does not require a reference wave. It then describes the receiver designs for coherent and non-coherent detection of ASK and FSK. For QASK, it outlines raising the input signal to the fourth power before bandpass filtering and frequency division to recover the transmitted bit sequence.
A loop antenna is a radio antenna consisting of a loop or coil of wire, tubing, or other electrical conductor with its ends connected to a balanced transmission line (or possibly a balun). There are two distinct antenna designs: the small loop (or magnetic loop) with a size much smaller than a wavelength, and the much larger resonant loop antenna with a circumference close to the intended wavelength of operation. Small loops have low radiation resistance and thus poor efficiency and are mainly used as receiving antennas at low frequencies. To increase the magnetic field in the loop and thus the efficiency, the coil of wire is often wound around a ferrite rod magnetic core; this is called a ferrite loop antenna. The ferrite loop is the antenna used in many AM broadcast receivers, with the exception of external loops used with AV Amplifier-Receivers and car radios; the antenna is often contained inside the radio's case. These antennas are also used for radio direction finding. In amateur radio, loop antennas are often used for low profile operating where larger antennas would be inconvenient, unsightly.
(c) WIkipedia
1. Digital modulation techniques are used to modulate digital information so that it can be transmitted via different mediums. Common digital modulation methods include binary amplitude shift keying (ASK), frequency shift keying (FSK), and phase shift keying (PSK).
2. FSK conveys information by changing the instantaneous frequency of a carrier wave. It is less susceptible to errors than ASK but has a larger spectrum bandwidth. PSK varies the phase of the transmitted signal. BPSK uses two phases while QPSK uses four phases.
3. The performance of digital modulation techniques can be compared using the energy per bit to noise power spectral density ratio (Eb/N0). Lower Eb/N0 values
The document discusses the Yagi-Uda antenna, which consists of multiple parallel dipole elements including a reflector, driven element, and multiple directors. It operates in the HF to UHF bands and provides a directional radiation pattern with moderate gain. Key advantages are its directionality and ability to operate at high frequencies. Common applications include television reception and radar systems where its directional properties and moderate gain are beneficial.
This document discusses various microwave measurement techniques, including:
- Power, VSWR, impedance, frequency, cavity Q, and wavelength measurements.
- Common measurement devices are vector network analyzers, spectrum analyzers, power meters, tunable detectors, slotted sections, and VSWR meters.
- Power is typically measured using diode detectors, bolometers, or thermocouples, which convert RF power to a measurable DC signal.
Microwave engineering involves the design of communication and navigation systems that operate in the microwave frequency range. Key topics in microwave engineering include microwave networks, scattering parameters, power dividers, couplers, filters, and amplifiers. Microwave systems have applications in areas like microwave ovens, radar, satellite communications, and personal communication systems.
This document discusses amplitude modulation (AM) as a type of modulation used to transmit information signals. Modulation involves varying a high frequency carrier signal by an information signal in order to transmit the information signal over long distances. In AM, the amplitude of the carrier signal is varied in accordance with the instantaneous amplitude of the modulating or information signal. This creates two new sideband frequencies above and below the carrier frequency equal to the modulation frequency. The carrier and sidebands together make up the modulated signal. Only a portion of the transmitted power is present in the sidebands containing the information, while the rest is wasted in the carrier.
This document discusses microwave devices, specifically directional couplers and isolators. It begins by defining microwaves and their applications such as telecommunications and radar. It then describes how directional couplers are passive devices that divide power through four ports and discusses their key figures of merit like coupling factor, isolation, and directivity. Isolators are also covered as two-port non-reciprocal devices that allow high power transmission in one direction while providing high attenuation in the opposite direction using Faraday rotation in a ferrite rod.
A horn antenna or microwave horn is an antenna that consists of a flaring metal waveguide shaped like a horn to direct radio waves in a beam. Horns are widely used as antennas at UHF and microwave frequencies, above 300 MHz.
This document discusses various digital modulation techniques including:
- Amplitude Shift Keying (ASK) which represents data as changes in signal amplitude.
- Frequency Shift Keying (FSK) which represents data as changes in carrier frequency.
- Phase Shift Keying (PSK) which represents data as changes in the phase of the carrier signal.
- Minimum Shift Keying (MSK) and Gaussian Minimum Shift Keying (GMSK) which are continuous phase modulation schemes used in wireless communications for their spectral efficiency.
- Quadrature Amplitude Modulation (QAM) which combines ASK and PSK to send multiple bits per symbol.
Ground wave propagation, Sky wave propagation, Space Wave propagation, Multi hop propagation, Duct wave propagation, LOS propagation, Ionospheric Layers
Network analysis of rf and microwave circuitsShankar Gangaju
This document discusses microwave network analysis and two-port network analysis. It begins by defining a microwave network as consisting of microwave devices and components coupled by transmission lines. It then discusses that at microwave frequencies, circuit analysis techniques like KCL and KVL cannot be used and S-parameters provide an alternative. The document defines S-parameters as a way to characterize networks using normalized power waves rather than voltages and currents. It provides properties and definitions of S-parameters for two-port networks, including what S11, S12, S21, and S22 represent. It also discusses uses of S-parameters and scattering matrices for modeling networks.
1. The document discusses microwave communication and components. It defines microwaves as electromagnetic waves with frequencies between 1GHz and 300GHz.
2. It describes various microwave frequency bands and their applications. Key applications discussed include wireless communications, radar, satellite communications and medical applications like cancer treatment and imaging.
3. Microwave components discussed include transmission lines, isolators, circulators, and E-plane tee junctions. Their properties and S-parameter matrices are defined. Microwave network parameters like Z, Y, H and ABCD are also introduced but it is noted they are not suitable for microwave frequencies.
Microwaves are electromagnetic waves with frequencies between 300MHz- 300GHz. Microwave communication uses microwave towers to transmit signals over long distances via line-of-sight. Key applications of microwaves include communication systems, satellite systems, radar for target detection, microwave heating for cooking and industrial processes, and microwave spectroscopy for materials analysis. Microwaves have advantages over lower frequencies including smaller antenna size, ability to penetrate some materials, and providing larger bandwidth for more channels in communication.
This document provides a summary of key components and operating principles of radar transmitters. It discusses the transmitter components including magnetrons, klystrons and traveling wave tubes that are used as microwave oscillators and amplifiers. It describes the use of waveguides and other components to transmit and manipulate microwave signals. Circulators and duplexers are discussed which allow transmit and receive signals to share an antenna. Operation and limitations of magnetron-based transmitters commonly used in radars are summarized. Factors affecting transmitter design such as output power, frequency stability and coherence are also highlighted at a high level.
This document provides an introduction to microwave engineering and microwave technology. It discusses key topics such as:
1) Microwaves are a form of electromagnetic radiation with wavelengths between 1 mm to 1 m and frequencies between 300 MHz to 300 GHz. Common applications include radar, wireless communication, and microwave ovens.
2) Microwaves propagate through waveguides such as rectangular, circular, and ridged waveguides. Waveguides allow microwaves to be transmitted with low power loss through reflection off the waveguide walls.
3) Microwave technology has advantages over lower radio frequencies including larger bandwidth, better directivity, smaller antenna size, and lower power consumption. Key applications areas are communication, remote
01_AME_U1_INTRODUCTION AND MICROWAVE FREQUENCY BANDS.pptxMrEmmanuelA
UNIT I introduces microwave systems and antennas. It discusses microwave frequency bands from 1 GHz to 300 GHz and key antenna concepts like near and far fields, gain, efficiency, impedance matching, and the Friis transmission equation. The unit also covers antenna pattern characteristics, radiated power and fields, and antenna noise temperature.
UNIT I provides an overview of key topics in microwave engineering and antenna fundamentals, including microwave frequency bands, antenna radiation mechanisms, near and far-field regions, antenna parameters like gain and pattern characteristics, impedance matching concepts, and noise modeling of microwave systems.
Microstrip Antenna for ISM Band (2.4GHz) Applications-A reviewIJERA Editor
The past decade has seen a rapid development of wireless communication systems. This continuous trend is bringing about a wave of new wireless devices placing several demands on the antenna such as size miniaturization, power consumption, simplicity, compatibility with printed-circuit technology, low profile, light weight, lower return loss and good radiation properties. This paper provides a comprehensive review of the research work done in the recent past by various authors on the design and optimization of the planar microstrip antenna operating in ISM band. An exhaustive list of reference has been provided.
This document discusses the fundamentals of microwave link design. It covers topics such as the frequency ranges used, types of microwave links based on distance (long haul, medium haul, short haul), components of a microwave link including indoor and outdoor units, antennas, and factors that affect microwave link performance such as multipath fading and rain attenuation. It also provides information on polarization, diversity techniques, link budget calculations, and considerations for deploying microwave links.
UNDERWATER ACOUSTIC MODEM FOR SHORT –RANGE SENSOR NETWORKS ijiert bestjournal
This document describes the design of an underwater acoustic modem for short-range sensor networks. It discusses the challenges of underwater acoustic communication and outlines the major components of acoustic modems, including transducers, analog transceivers, and digital control platforms. The document then provides details on the design of an amplitude-shift keying acoustic modem, including the transmitter, receiver, and testing results. It concludes that the designed modem represents a low-cost alternative to existing commercial underwater acoustic modems.
This document discusses microwave passive components. It begins with defining the microwave frequency range from 300 MHz to 300 GHz. It then discusses scattering matrix representation and properties for microwave components. Various microwave junctions and couplers are described like magic tees, directional couplers, and hybrid rings. Important microwave devices are discussed like isolators, circulators, and attenuators. Cylindrical cavity resonators are also mentioned. S-matrix formulation is presented for various microwave components.
This document discusses transmission lines and their key characteristics. It begins by defining a transmission line as a medium that directs the transmission of energy, such as electromagnetic waves, from one place to another. Transmission lines are designed to carry alternating current and have a more specific meaning in communications and electronics where their wave nature must be accounted for. The document then discusses some key aspects of transmission line operation, including that voltage and current are functions of both time and position along the line. It provides examples of common transmission line structures and discusses transmission line equivalent circuits and relevant equations for modeling transmission line behavior.
This document provides information about designing a microwave link between two sites in Pakistan for a semester project. It includes:
1) Details of the two sites and student information.
2) An introduction explaining microwave radio relay technology and how it is used to transmit signals over long distances using line-of-sight paths.
3) Technical explanations of key concepts in microwave communication systems like frequency, wavelength, free space loss, antenna gain, and how they relate to designing an optimal microwave link.
This document discusses microwave communication and digital microwave communication systems. It defines microwave frequencies as ranging from 300 MHz to 300 GHz, but focusing on 3 GHz to 30 GHz for communication. Digital microwave communication modulates a digital baseband signal onto an intermediate frequency or directly onto a microwave carrier frequency using techniques like PSK and QAM. It describes the evolution of microwave systems from analog to digital and small to large capacities. It also outlines different types of digital microwave stations and relay stations.
Microwave communication by abhishek mahajanabhimaha09
This document discusses microwave communication and digital microwave communication systems. It defines microwave frequencies as ranging from 300 MHz to 300 GHz, but focuses on 3 GHz to 30 GHz for communication. Digital microwave communication modulates a digital baseband signal onto an intermediate frequency or directly onto a microwave carrier using techniques like PSK, QAM, ASK, and FSK. It describes the development of analog and digital microwave systems over time with increasing transmission capacities. It also discusses different types of digital microwave stations and relay stations.
This document provides an overview of microwave engineering and describes key concepts such as transmission lines, scattering parameters, couplers, and filters. The objectives are to provide the basic theory of microwaves and examine applications in modern communication systems. Microwave engineering involves the design of systems like radar, satellite communications, and wireless networks that operate in the microwave frequency range from 300 MHz to 300 GHz.
This document discusses EMI/EMC, including various sources of electromagnetic interference and transients that can affect electronic systems, such as crosstalk between transmission lines, switching transients, and lightning strikes. It also covers open area test sites and measurements for evaluating radiated emissions and susceptibility of equipment to electromagnetic fields. Key points include the importance of minimizing scattering at test sites, and using antennas and measurement precautions appropriately based on frequency ranges and standards.
Wireless channels in wireless communicationPreciousMposa1
The document discusses various wireless channel characteristics including large scale path loss models, small scale fading parameters, and multipath effects. It describes free space path loss and the two-ray ground reflection model for large scale path loss. For small scale fading, it discusses parameters such as coherence bandwidth and Doppler spread/coherence time that characterize multipath time delay spread and Doppler spread fading. It also summarizes multipath delay spread which occurs when a signal takes multiple paths causing interference from delayed components.
Airport servilanc radar system Asr 8 usful presentationFaraidonSafi
1. The ASR-8 is an airport surveillance radar system with dual channels that allows air traffic controllers to monitor aircraft within 60 nautical miles.
2. It uses components like a diplexer, circulator, and dummy load to switch transmitter power to the antenna and receive returning signals while protecting the receiver.
3. Maintenance can be performed on one channel while the other remains operational, and components like the diplexer and waveguide switches allow both channels to operate simultaneously in a frequency diversity mode for improved detection.
This document provides an overview of mobile computing and mobile communication systems. It discusses various topics including:
- Guided and unguided signal transmission methods. Guided uses wires/fibers while unguided uses wireless electromagnetic signals.
- Signal propagation frequencies for different transmission standards like FM radio, GSM, UHF. It also discusses antenna types used for transmission and reception of signals.
- Modulation techniques and standards for 1G to 4G mobile systems. 1G supported only voice, while newer standards enable higher data rates and support for data/multimedia. GSM is described as a prominent 2G standard.
- Concepts of mobility including user mobility and device mobility. It also discusses applications and
This document compares the performance of QAM modulation in Rayleigh and Rician fading channels using Simulink. It first provides background on line-of-sight transmission and the factors that impact wireless signals, including attenuation, noise, multipath effects. It then describes Rayleigh and Rician fading channels and their statistical distributions. QAM modulation is introduced along with different constellation types. Finally, the document describes simulating Rayleigh and Rician fading channels in Simulink to analyze the performance of QAM modulation under each channel condition in 3 sentences or less.
Ge6075 professional ethics in engineering unit isrirenga
This document discusses various human values including honesty, morality, ethics, and courage. It defines these concepts and explains how they relate to each other. Some key points include:
- Human values like honesty, fairness and compassion form the foundation for human life and society.
- Morality refers to principles of right and wrong behavior while ethics deals with standards of conduct within a profession.
- Values describe what is important to individuals and communities and help shape character.
- Aspects of honesty include truthfulness, trustworthiness, and maintaining integrity and responsibility.
- Courage involves rationally accepting risks and difficult tasks with self-confidence.
Bioelectric potentials like electrocardiograms, electroencephalograms, and electromyograms can be measured using electrodes that convert ionic currents in the body into electric signals. An electrocardiogram measures the electric potentials generated by heart muscle contractions and shows characteristic P, QRS, and T waves. The heart is divided into four chambers with the right atrium and ventricle receiving deoxygenated blood and the left atrium and ventricle pumping oxygenated blood. Electroencephalograms measure brain activity through electrodes on the scalp and show different wave patterns based on sleep states. Electromyograms detect muscle fiber activation.
1. The document discusses various topics related to work ethics including the interdependence of industry and society, the importance of hard work and productivity, and maintaining a conducive work environment.
2. It also discusses the importance of valuing time, noting that time is a rare and perishable resource. Anecdotes are provided to illustrate the value of different units of time.
3. Meditation and its benefits are described, including reducing stress and negative emotions. Different types of meditation such as mindfulness meditation are explained.
Microwave devices can be passive or active. Passive devices include terminations to absorb microwave power without reflection, as well as directional couplers and phase shifters. Terminations include matched loads made of lossy materials placed in waveguides to absorb all incident power. Directional couplers are four-port devices that couple power between two connected waveguides in one direction only. Phase shifters provide a variable phase shift without changing the physical path length using materials like ferrites or dielectrics.
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The rivalry between prominent international actors for dominance over Central Asia's hydrocarbon
reserves and the ancient silk trade route, along with China's diplomatic endeavours in the area, has been
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politics, and conventional and nontraditional security are all explored and explained by the researcher.
Using Mackinder's Heartland, Spykman Rimland, and Hegemonic Stability theories, examines China's role
in Central Asia. This study adheres to the empirical epistemological method and has taken care of
objectivity. This study analyze primary and secondary research documents critically to elaborate role of
china’s geo economic outreach in central Asian countries and its future prospect. China is thriving in trade,
pipeline politics, and winning states, according to this study, thanks to important instruments like the
Shanghai Cooperation Organisation and the Belt and Road Economic Initiative. According to this study,
China is seeing significant success in commerce, pipeline politics, and gaining influence on other
governments. This success may be attributed to the effective utilisation of key tools such as the Shanghai
Cooperation Organisation and the Belt and Road Economic Initiative.
Adaptive synchronous sliding control for a robot manipulator based on neural ...IJECEIAES
Robot manipulators have become important equipment in production lines, medical fields, and transportation. Improving the quality of trajectory tracking for
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challenging problem because robot manipulators are complex nonlinear systems
and are often subject to fluctuations in loads and external disturbances. This
article proposes an adaptive synchronous sliding control scheme to improve trajectory tracking performance for a robot manipulator. The proposed controller
ensures that the positions of the joints track the desired trajectory, synchronize
the errors, and significantly reduces chattering. First, the synchronous tracking
errors and synchronous sliding surfaces are presented. Second, the synchronous
tracking error dynamics are determined. Third, a robust adaptive control law is
designed,the unknown components of the model are estimated online by the neural network, and the parameters of the switching elements are selected by fuzzy
logic. The built algorithm ensures that the tracking and approximation errors
are ultimately uniformly bounded (UUB). Finally, the effectiveness of the constructed algorithm is demonstrated through simulation and experimental results.
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significantly reduced.
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solve this issue, this paper develops a hybrid Deep Learning (DL) model specifically designed for intrusion
detection in smart grids. The proposed approach is a combination of the Convolutional Neural Network
(CNN) and the Long-Short-Term Memory algorithms (LSTM). We employed a recent intrusion detection
dataset (DNP3), which focuses on unauthorized commands and Denial of Service (DoS) cyberattacks, to
train and test our model. The results of our experiments show that our CNN-LSTM method is much better
at finding smart grid intrusions than other deep learning algorithms used for classification. In addition,
our proposed approach improves accuracy, precision, recall, and F1 score, achieving a high detection
accuracy rate of 99.50%.
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
Introduction- e - waste – definition - sources of e-waste– hazardous substances in e-waste - effects of e-waste on environment and human health- need for e-waste management– e-waste handling rules - waste minimization techniques for managing e-waste – recycling of e-waste - disposal treatment methods of e- waste – mechanism of extraction of precious metal from leaching solution-global Scenario of E-waste – E-waste in India- case studies.
A review on techniques and modelling methodologies used for checking electrom...nooriasukmaningtyas
The proper function of the integrated circuit (IC) in an inhibiting electromagnetic environment has always been a serious concern throughout the decades of revolution in the world of electronics, from disjunct devices to today’s integrated circuit technology, where billions of transistors are combined on a single chip. The automotive industry and smart vehicles in particular, are confronting design issues such as being prone to electromagnetic interference (EMI). Electronic control devices calculate incorrect outputs because of EMI and sensors give misleading values which can prove fatal in case of automotives. In this paper, the authors have non exhaustively tried to review research work concerned with the investigation of EMI in ICs and prediction of this EMI using various modelling methodologies and measurement setups.
2. Radio Frequency
• It is any of the electromagnetic wave frequency that lie in the
range extending from around 3KHz to 300GHz, which include
those frequencies used for communications (or) radar signals
• RF components are
• Antenna,
• Oven
• Circuit elements,
• radio applications
• It is used in digital circuits
3. Introduction
What is Microwave?
Microwaves are electromagnetic waves of wavelengths
ranging from about 30cm down to about 0.3mm corresponding
frequency range of 109 Hz to 1012 Hz.
Microwave Engineering deals with Systems operating at these
frequencies.
3
4. Microwave engineering
• Used to design of Communication/navigation systems in the
microwave frequency range
Applications
– Microwave oven
– Radar (RADAR is an electromagnetic system for the detection and
location of target objects such as aircraft, ships, spacecraft, vehicles,
people, and the natural environment which can reflect a signal back).
– Satellite communication
– TV etc.,
• Microwave is a region in the electromagnetic wave spectrum in the
frequency range from 300MHz to 300GHz.
• This corresponds to a range of wavelength from 100cm to 1mm in
frequency space
5. At Microwave frequencies, the conventional electronic
circuits radiate more and more power from the circuit.
New Circuit techniques for handling signals in this
frequency are needed.
Increasing frequency to microwave range is the fact that the
propagation time for signals from one point in a circuit to
another becomes comparable with time period of the signal.
5
6. Thus conventional Low frequency circuit analysis
techniques based on KVL and KCL concepts are
inapplicable to microwave circuits.
It becomes necessary to carryout analysis of microwave
circuit in terms of electric and magnetic fields.
6
7. Microwave Frequency Bands in
Radio Spectrum
The entire Electromagnetic spectrum is broadly classified into two
regions namely
Radio Spectrum – 0 to 300 GHz
Radio frequency Spectrum: 300KHz to 300MHz
Microwave frequency spectrum: 300 MHz to 300 GHz
Optical Spectrum – 300GHz to infinity
The term Microwave is commonly used to designate frequencies
ranging from 300 MHz to 300GHz and wavelengths in air ranging from
100 cm – 1 mm.
The word Microwave means very short wave, which is the shortest
wavelength region of the radio spectrum and a part of the
electromagnetic spectrum.
7
9. • Relationship between frequency ( ) and wavelength ( )
where c is the speed of light
• Energy of a photon
where h is Planck’s constant
c
hE
Wavelength
10. IEEE Frequency Band Designations
Band Designator Frequency (GHz)
Wavelength in Free
Space (centimeters)
Radio
wave
Region HF 0.003 to 0.030 10000 to 1000
VHF 0.030 to 0.300 1000 to 100
UHF 0.300 to 1 100 to 30.0
MicrowaveRegion
L band 1 to 2 30.0 to 15.0
S band 2 to 4 15 to 7.5
C band 4 to 8 7.5 to 3.8
X band 8 to 12 3.8 to 2.5
Ku band 12 to 18 2.5 to 1.7
K band 18 to 27 1.7 to 1.1
Ka band 27 to 40 1.1 to 0.75
illimeterwave
Region
V band 40 to 75 0.75 to 0.40
W band 75 to 110 0.40 to 0.27
mm 110 to 300 0.27 to 0.10
Submillimeter
300 to 3000
10
11. Characteristics of Microwave
• Wavelengths are very small
• Pulses are very short – used for distance or time measurement
• Very large BW is available-because it has HF
• Radiation penetrates fog and clouds, travels in straight lines and
give reflection – used for RADAR systems
• It is necessary for communications through satellite – because it
can pass through ionosphere which reflects lower frequency
radio waves
• Microwave Power is absorbed by water (or) any other material
containing water so that microwaves can be used for heating and
drying
12. Advantages of Microwaves
• It does not require a dedication path between stations
• It can carry large quantities of information
• Requires relatively small antennas
• Easily propagates through ionised layers-most suited for satellite
communication
• Transmission distance is large – less no. of repeaters are required
for amplification
• Propagation delay is negligible (or) minimum
• Signal cross talk is eliminated
• Highly reliable systems
• Less maintenance is required
13. Advantages of Microwaves
High Bandwidth Capability – More information
Capacity
High antenna Gain – ShortestWavelength
LOS Propagation – Not affected by ionosphere
Fading effect and reliability – Due to LOS, less Fading
effects occurs at high frequencies
Transparency property of microwaves
Low power requirements
2
4
eA
G
13
14. Disadvantages of Microwave
At microwave frequencies, circuit design is complex
Measurement at microwave frequencies are difficult
LOS propagation limits the use of microwave
15. Applications of Microwaves
Long Distance Communication
Terrestrial Communication
Radars
Defence Applications
AirTraffic Controlling and Navigation
Microwave heating
Microwave oven
Remote Sensing
Wireless data Networks
Astronomy
Medical Applications
Heating & detection of foreign bodies in food
15
16. Review of Low Frequency
Parameters
A Microwave Network is formed when several microwave
devices and components such as Sources, attenuators,
resonators, filters, amplifiers etc are coupled by transmission
lines or waveguides for the desired transmission of a
microwave signal.
The point of interconnection of two or more devices is called a
Junction.
In Low Frequency Network, a port is a pair of terminal.
In a Microwave Network, a port is a reference plan transverse
to the length of the microwave transmission line or waveguide.
16
17. At Low Frequencies, Physical Length of the network is much
smaller than the wavelength of the signal transmitted.
The measureable input and output variables are voltage and
current which can be related interms of the
Impedance Z-Parameters
AdmittanceY-Parameters
Hybrid Parameters
ABCD Parameters
These Parameters can be measured under short or open
circuit condition for use in the analysis of the circuit.
17
18. In Microwave frequency, Physical Length of the component
or line is much Larger than the wavelength of the signal
transmitted.
Voltages and currents cannot be uniquely defined at a given
point in a single conductor/waveguide.
18
19. Low Frequency Microwave
Electronic circuits operating at
low frequency, port is a pair of
terminals
Port is a reference plane transverse
to the length of the microwave
transmission line (or) waveguide
Physical length of the network
is smaller than wavelength of
signal transmitted
Physical length of the network is
larger than wavelength of signal
transmitted
Input and Output variables are
measured by voltage and current
Voltage and Current cannot be
uniquely defined at a given point in
a single waveguide
Circuits are analyzed using
Z,Y,H and ABCD parameters
Circuits are analyzed using S
parameters
These parameters may be
measured under Short (or) Open
circuit condition for the analysis
of the circuit
S-parameters linearly relate to the
amplitude of scattered waves with
those of incident waves
20. The measurement of Z-Parameter, Y-Parameter, H-parameter
and ABCD Parameters is difficult at microwave frequencies
due to the following reasons:
Absence of unique definition of voltage and current
Short and open circuit are not easily achieved for a wide
range of frequency
Presence of active devices makes the circuit unstable for
open and short circuit analysis.
20
21. Analysis of Microwave Circuits
• Microwave Circuits are analyzed using Scattering (S-
parameters) which relates the amplitude of scattered waves
(Reflected and transmitted) with those of incident waves.
• For Microwave circuits analysis, S- parameters can be
related to the Z/Y/ABCD Parameters.
21
22. Two Port Networks
Generalities: The standard configuration of a two port:
The NetworkInput
Port
Output
Port
+
_ _
+
V1 V2
I1 I2
The network ?
The voltage and current convention ?
22
24. Two Port Networks
Z parameters:
1
1
11 I
V
z
0
2
I
2
1
12 I
V
z
0
1
I
1
2
21 I
V
z
0
2
I
2
2
22 I
V
z
0
1
I
z11 is the impedance seen looking into port 1
when port 2 is open.
z12 is a transfer impedance. It is the ratio of the
voltage at port 1 to the current at port 2 when
port 1 is open.
z21 is a transfer impedance. It is the ratio of the
voltage at port 2 to the current at port 1 when
port 2 is open.
z22 is the impedance seen looking into port 2
when port 1 is open.
24
25. Two Port Networks
Y parameters:
1
1
11 V
I
y
0
2
V
2
1
12 V
I
y
0
1
V
1
2
21 V
I
y
0
2
V
2
2
22 V
I
y
0
1
V
y11 is the admittance seen looking into port 1
when port 2 is shorted.
y12 is a transfer admittance. It is the ratio of the
current at port 1 to the voltage at port 2 when
port 1 is shorted.
y21 is a transfer impedance. It is the ratio of the
current at port 2 to the voltage at port 1 when
port 2 is shorted.
y22 is the admittance seen looking into port 2
when port 1 is shorted.
* notes 25
26. Two Port Networks
Z parameters: Example 1
Given the following circuit. Determine the Z parameters.
8
20 20
10
+
_
+
_
V1 V2
I1 I2
Find the Z parameters for the above network.
26
27. Two Port Networks
Z parameters: Example 1 (cont 1)
For z11:
Z11 = 8 + 20||30 = 20
For z22:
For z12:
Z22 = 20||30 = 12
2
1
12 I
V
z
0
1
I
8
20 20
10
+
_
+
_
V1 V2
I1 I2
2
2
1 8
3020
2020
xI
xxI
V
Therefore:
8
8
2
2
12
I
xI
z = 21z
27
28. Two Port Networks
Z parameters: Example 1 (cont 2)
The Z parameter equations can be expressed in
matrix form as follows.
2
1
2
1
128
820
I
I
V
V
2
1
2221
1211
2
1
I
I
zz
zz
V
V
28
29. Two Port Networks
Hybrid Parameters: The equations for the hybrid parameters are:
2
1
2221
1211
2
1
V
I
hh
hh
I
V
1
1
11
I
V
h
V2 = 0
2
1
12
V
V
h
I1 = 0
1
2
21
I
I
h
V2 = 0
2
2
22
V
I
h
I1 = 0
29
30. Interconnection of Two Port Networks
Three ways that two ports are interconnected:
* Parallel
* Series
* Cascade
ba
yyy
ba
zzz
ba
TTT
ya
yb
za
zb
Ta Tb
parametersY
parametersZ
parametersABCD
30
31. Interconnecting Networks: Series Connection
2
1
22
11
2
1
"'
"'
i
i
vv
vv
v
v
Z
"''
"'"'
2222"2121
12121111
ZZZZ
ZZZZ
Z"Z'Z
Note that individual networks may not be connected indiscriminately.
31
32. Interconnecting Networks: Parallel Connection
2
1
22
11
2
1
"'
"'
v
v
ii
ii
i
i
Y
"'"'
"'"'
22222121
12121111
YYYY
YYYY
Y"Y'Y
Note that individual networks may not be connected indiscriminately.
32
33. III – ABCD Parameters
)(
)(
221
221
iDCvi
iBAvv
+
+
2
2
1
1
"
"
""
""
''
''
'
'
i
v
DC
BA
DC
BA
i
v
33
35. High Frequency Parameters
• The S-parameter is called high frequency parameter
• To characterize any network at microwave frequencies S-
parameters are used
• The S-parameters provide complete description of network
• S-parameters can be converted into other matrix parameters if
needed
36. Formulation of S-parameters
Scattering Matrix:
• It is a square matrix which gives all the combinations of power
relationship between the various input and output port of a
microwave junction
• S-parameters are complex numbers
• S-matrix is a useful analytical technique for studying multiport
microwave networks
• The elements of the scattering matrix are called scattering
coefficients or scattering parameters
• The importance of S-parameter is derived from the fact that
practical system characterizations can no longer be accomplished
through simple open/short circuit measurements
37. • Because, when we attempt to create a short circuit with wire:
the wire itself possess an inductance of substantial magnitude at
high frequency. Also the open circuit leads to capacitive loading
at the terminal
• In either case, the open/short circuit conditions needed to
determine z, h, y and ABCD parameters can no longer be
guaranteed
• S-parameters denote the fraction of incident power reflected at a
port and transmitted to other ports
• The addition of phase information allows the complete
description of any linear circuit
38. S-matrix Representation of Two-port Network:
• The incident and reflected wave amplitudes of microwaves at any
port are used to characterize a microwave circuit
• The amplitudes are normalized in such a way that the square of
any of these variables gives the average power
• Input power at nth port, Pin = ½ l an l2
• Reflected power at nth port, Prn = ½ l bn l2
Where an represent normalized incident wave peak amplitude
bn represent normalized reflected wave peak amplitude at nth
port
39. • The concept of S-parameter may come from the fact that RF and
microwave circuit may contain some discontinuity in the signal
path.
• At discontinuity, the wave scattered in different directions
containing “infinite number of higher order modes”
• These modes attenuated very fast after a short distance from the
point of discontinuity within about a quarter wavelength
• Then, only the executed modes comes out from the different ports.
• All these emerging waves are considered as reflected waves at the
corresponding ports.
• The waves entering the ports are considered the input (or) incident
wave
40. Losses of S-parameters
Insertion loss:
• It is the loss of signal power resulting from the insertion of a
device in a transmission line which is usually described in
decibels(dB).
Attenuation loss (or) Transmission loss:
• It is the measure of the power loss due to signal absorption in the
device
Reflection loss:
• It is the measure of the power loss during transmission due to
the reflection of the signal as a result of impedance mismatch
Return loss:
• It is the measure of the power reflected by a line (or) network
through a line
41. Properties of S-Matrix
• S-matrix [S] is always a square matrix of order (n x n) and its
elements are complex quantities (real and imaginary part)
• [S] is a symmetric matrix (i.e) Sij=Sji
• [S] is a unitary matrix (i.e) [S][S]* = [I]
Where [S]* - Complex Conjugate of [S]
[I] - Unit Matrix (or) Identity matrix of same order as
that of [S]
• Under perfect matched conditions; the diagonal elements of [S]
are zero
• The sum of product of each term of any row (or) column
multiplied by the complex conjugate of the corresponding terms
of any other row ((or) column) is zero
jkforSS ij
n
i
ik
0*
1
42. References
• Reinhold Ludwig and Gene Bogdanov, “RF Circuit
Design: Theory and Applications”, Pearson Education
Inc., 2011
• Robert E Colin, “Foundations for Microwave
Engineering”, John Wiley & Sons Inc, 2005
• Annapurna Das and Sisir K Das,’ Microwave
Engineering”, Tata Mc Graw Hill Publishing
Company Ltd, New Delhi, 2005