Microwave, Radar & RF Engineering

474 Pages·2018·22.311 MB·English

by  Prakash Kumar Chaturvedi

Prakash Kumar Chaturvedi
Microwave, Radar
& RF Engineering
With Laboratory Manual
Microwave, Radar & RF Engineering
Prakash Kumar Chaturvedi
Microwave, Radar & RF
Engineering
With Laboratory Manual
123
Prakash KumarChaturvedi
Department ofElectronics &
Communication Engineering
SRMUniversity, NCRCampus
Ghaziabad, Uttar Pradesh
India
ISBN978-981-10-7964-1 ISBN978-981-10-7965-8 (eBook)
https://doi.org/10.1007/978-981-10-7965-8
LibraryofCongressControlNumber:2018931502
©SpringerNatureSingaporePteLtd.2018
Thisworkissubjecttocopyright.AllrightsarereservedbythePublisher,whetherthewholeor
part of the material is concerned, specifically the rights of translation, reprinting, reuse of
illustrations,recitation,broadcasting,reproductiononmicrofilmsorinanyotherphysicalway,
andtransmissionorinformationstorageandretrieval,electronicadaptation,computersoftware,
orbysimilarordissimilarmethodologynowknownorhereafterdeveloped.
Theuseofgeneraldescriptivenames,registerednames,trademarks,servicemarks,etc.inthis
publication does not imply, even in the absence of a specific statement, that such names are
exemptfromtherelevantprotectivelawsandregulationsandthereforefreeforgeneraluse.
Thepublisher,theauthorsandtheeditorsaresafetoassumethattheadviceandinformationin
thisbookarebelievedtobetrueandaccurateatthedateofpublication.Neitherthepublishernor
the authors or the editors give a warranty, express or implied, with respect to the material
containedhereinorforanyerrorsoromissionsthatmayhavebeenmade.Thepublisherremains
neutralwithregardtojurisdictionalclaimsinpublishedmapsandinstitutionalaffiliations.
Printedonacid-freepaper
ThisSpringerimprintispublishedbytheregisteredcompanySpringerNature
SingaporePteLtd.partofSpringerNature
Theregisteredcompanyaddressis:152BeachRoad,#21-01/04GatewayEast,
Singapore189721,Singapore
Preface
Unprecedented growth in the application of microwave has taken place
duringthelasttwotothreedecades,especiallyinmobilecommunication,TV
transmission, industrial/domestic applications, satellite communication,
telemetry, RADAR/navigational aids, etc. This rapid development in the
microwaveandthatofdigitaltechnologieshassynergised,leadingtofurther
accelerated growth rate. This has created an increased demand for trained
engineers, in civilian as well as in defence organizations.
Thisbookmeetsthecompleteneedofthestudentsofengineeringcourses,
i.e. B.S., B.E., M.S., M.Tech., M.Sc., in various countries. However, the
students need to have prior knowledge of electromagnetics. The special
features of this book are as follows: (a) It contains fundamental concepts
andprinciplesbehindmicrowaveengineeringexplainedinastudent-friendly
lucid language, keeping a balance between physical and analytical approa-
ches, (b) contains a large number of solved and unsolved problems after
every chapter, for developing practical knowledge, (c) has around 400 fig-
ures, with special effort put in, for giving realistic numerical values in the
graphs/dimensionsofthecomponentsanddevices,forgettingarealfeeland
visualisationofthatdevice,whichismissinginmanytextbooks,and(d)has
15 important experiments, giving full theory, procedures, precautions, and
sample readings and observations as expected in each experiment, followed
by quiz/viva questions for the benefit of the students and the instructors.
This book consists of 12 chapters along with an annexure giving related
constants and finally an index. Chapter 1 introduces the subject along with
thebehaviouroflumpedcomponentsL,C,andRatmicrowavefrequencies,
microwave heating mechanism, concept of CW/pulsed signals, decibel,
anechoic chamber, EMI/EMC, radiation hazards, etc. Chapter 2 summarizes
thebasicsofwavepropagationindifferentmodes/cut-offfrequencies,etc.,in
transmission lines and waveguides. It also touches a bit on microstrip lines.
Impedance matching covering Smith chart using single and double stub has
alsobeengiven.Chapter3coverscavityresonatorsofvarioustypesandtheir
tuning and coupling. Chapter 4 describes a variety of components like T,
directional couplers, isolators used in microwave circuits. Chapter 5 firstly
covers limitations of conventional tubes and then various microwave tubes,
e.g. klystron tube, magnetron, TWT, used as oscillators and amplifiers.
Chapter6coverssixtypesoftransistorsandeighttypesofdiodes,withtheir
working as oscillators and amplifiers. Chapter 7 presents measurement
v
vi Preface
techniquesofimportantparametersandrelatedinstruments.Chapter8covers
theoryofmicrowavepropagationinspaceandthroughamicrowaveantenna.
Chapter 9 deals with working of various types of RADARs. Chapter 10
introduces filter design theory and design techniques giving emphasis on
microstrip line filters, which canbe verified by using standardsoftware, e.g.
ADS. Chapter 11 gives basic concepts of RF amplifiers, oscillators, and
mixersusingSmithchartsforstabilityconsiderations.Chapter12presents15
simple laboratory experiments of the undergraduate level, along with con-
ventional guidelines for students.
Iamverythankfultomylifepartnerandchildren,whohavebeenasource
ofinspiration,having providedcongenialatmosphereeveninoddhoursand
having given useful suggestions while writing the manuscripts of this book.
I am also thankful to authors of various books (as per the references
given),which Ihavereferredtoduring thelong period Ihavebeenteaching
this subject in various institutions.
Finally, I convey my thanks to Springer for their painstaking effort for
bringing the book in standard and excellent form.
However, if you notice any mistake, error, and discrepancy, it would be
highly appreciated if you bring it tomynoticealong with your feedback for
improvement of the book.
New Delhi, India Prof. Prakash Kumar Chaturvedi
Contents
1 Introduction to Microwaves .. .... .... .... .... ..... .... 1
1.1 Introduction. ..... .... .... .... .... .... ..... .... 2
1.2 History of Microwaves . .... .... .... .... ..... .... 2
1.3 Characteristic Features and Advantages
of Microwaves ... .... .... .... .... .... ..... .... 3
1.4 CW and Pulsed Microwave Power .... .... ..... .... 10
1.5 Decibel—A Unit to Measure Relative Power, Voltage
Level, Etc... ..... .... .... .... .... .... ..... .... 11
1.6 Anechoic Chamber: The EM Radiation Free Area . .... 13
1.7 Electromagnetic Interference (EMI) and
Electromagnetic Compatibility (EMC) . .... ..... .... 13
1.8 Radiation Hazards for Human Body/Birds, Etc. ... .... 13
1.9 Application Areas of Microwaves. .... .... ..... .... 14
1.10 Summary... ..... .... .... .... .... .... ..... .... 16
2 Transmission Lines, Waveguides, Strip Lines, and Stub
Matching by Smith Chart.... .... .... .... .... ..... .... 19
2.1 Introduction. ..... .... .... .... .... .... ..... .... 20
2.1.1 Polarisation of Waves: Circular or Elliptical
or Linear .... .... .... .... .... ..... .... 21
2.2 Propagation of Waves in the Transmission Line... .... 23
2.3 Waveguides: Circular and Rectangular . .... ..... .... 27
2.4 Propagation of Waves in Rectangular Waveguide.. .... 27
2.4.1 TE Waves in Rectangular Waveguides
Electrical Field and Magnetic Field
Equations.... .... .... .... .... ..... .... 31
2.4.2 Non-existence of TEM Mode
in Waveguides.... .... .... .... ..... .... 34
2.4.3 TM Waves in Rectangular Waveguide:
Electric and Magnetic Field Equation ... .... 34
2.4.4 Cut-offFrequenciesofDominantModesand
Degenerate Modes in TE/TM Wave..... .... 35
2.4.5 Mode Excitation in Rectangular
Waveguides.. .... .... .... .... ..... .... 36
2.4.6 WaveImpedance(Z )inTMandTEWaves
w
in lossless Lines... .... .... .... ..... .... 38
2.4.7 Power Transmission and Losses
in Waveguide. .... .... .... .... ..... .... 41
vii
viii Contents
2.4.8 Breakdown Power—Power Handling
Capacity in Rectangular Waveguide..... .... 42
2.4.9 Guide Wavelength, Group Velocity, and
Phase Velocity.... .... .... .... ..... .... 42
2.5 Propagation in Circular Waveguides... .... ..... .... 45
2.5.1 TE Waves in Circular Waveguide
E- and H-Field Equations ... .... ..... .... 45
2.5.2 TM Modes in Circular Waveguide:
E- and H-field Equations.... .... ..... .... 46
2.5.3 Cut-off Wavelength in Circular Waveguide,
Dominant and Degenerate Modes . ..... .... 47
2.5.4 Phase Velocity, Group Velocity, Guide
Wavelength, and Wave Impedance in
Circular Waveguides ... .... .... ..... .... 48
2.5.5 Power Transmission and Attenuation Loss
in Circular Waveguide.. .... .... ..... .... 50
2.5.6 Power Handling Capacity and Breakdown
Power Limits in Circular Waveguide.... .... 51
2.5.7 TEM Wave in Circular Waveguide
Do Not Exist. .... .... .... .... ..... .... 52
2.5.8 Excitation of Modes.... .... .... ..... .... 52
2.5.9 Advantages, Disadvantages, and
Applications of Circular Waveguides.... .... 53
2.6 Strip Lines and Microstrip Lines.. .... .... ..... .... 53
2.6.1 Microwave Component Using Strip Lines.... 58
2.6.2 Microwave IC (MIC) and Monolithic
Microwave IC (MMIC) . .... .... ..... .... 58
2.7 Impedance Matching... .... .... .... .... ..... .... 59
2.7.1 Power Losses Due to Impedance
Mismatch.... .... .... .... .... ..... .... 59
2.7.2 Quarter Wave Transformer for Impedance
Matching .... .... .... .... .... ..... .... 60
2.7.3 Smith Chart and Its Applications.. ..... .... 60
2.7.4 Single- and Double-Stub Matching in
Lossless Lines .... .... .... .... ..... .... 66
3 Microwave Cavity Resonators .... .... .... .... ..... .... 81
3.1 Introduction. ..... .... .... .... .... .... ..... .... 82
3.2 Rectangular Waveguide Resonators of Lossless
Lines.. .... ..... .... .... .... .... .... ..... .... 82
3.3 Circular Waveguide Resonators of Lossless Line .. .... 84
3.4 Coaxial Line Resonators.... .... .... .... ..... .... 85
3.5 Re-entrant Cavity Resonator. .... .... .... ..... .... 87
3.6 Cylindrical Hole-and-Slot Cavity Resonator . ..... .... 87
3.7 Microstrip Line Resonators.. .... .... .... ..... .... 88
3.8 Coupling of Cavities with the Line: Reflection and
Transmission Types ... .... .... .... .... ..... .... 89
3.9 Coupling Factor .. .... .... .... .... .... ..... .... 91
3.10 Frequency Tuning of Cavity. .... .... .... ..... .... 92
Contents ix
3.11 The Q Factor of a Cavity Resonator... .... ..... .... 92
3.12 Solved Problems.. .... .... .... .... .... ..... .... 95
4 Microwave Components and Their Scattering Matrices. .... 101
4.1 Introduction. ..... .... .... .... .... .... ..... .... 102
4.2 Coaxial Cables and Connectors... .... .... ..... .... 105
4.3 Microwave Waveguide Junctions: 4-Types.. ..... .... 108
4.4 H-Plane Tee Junction (Current Junction).... ..... .... 108
4.5 E-Plane Tee Junction (Voltage Junction).... ..... .... 113
4.6 E–H-Plane Tee (Hybrid Junction/Magic Tee) ..... .... 116
4.6.1 Applications and Limitations
of Magic Tee. .... .... .... .... ..... .... 121
4.7 Hybrid Ring (Rat-Race Junction) . .... .... ..... .... 121
4.8 Directional Couplers for Power Sampling/Testing.. .... 122
4.8.1 Various Types of Directional
Couplers (DC).... .... .... .... ..... .... 125
4.9 Bends, Twists, and Transitions ... .... .... ..... .... 128
4.10 Attenuators and Terminators. .... .... .... ..... .... 129
4.11 Iris and Screw Posts for Impedance Matching/
Introducing L or C .... .... .... .... .... ..... .... 130
4.12 Signal Tapping/Feeding and Detecting . .... ..... .... 132
4.12.1 Probes and Loops (for Tapping/Exciting/
Feeding lx Power into a Waveguide or for
Taking Out Microwave Power from the
Waveguide) .. .... .... .... .... ..... .... 132
4.12.2 Diode Detectors Using Schottky Barrier
Diode (SBD) . .... .... .... .... ..... .... 132
4.13 Wave Metres/Frequency Metre... .... .... ..... .... 133
4.14 Faraday Rotation and Ferrite Devices—Isolators,
Gyrators, and Circulators ... .... .... .... ..... .... 135
4.14.1 Isolator.. .... .... .... .... .... ..... .... 137
4.14.2 Gyrator . .... .... .... .... .... ..... .... 139
4.14.3 Circulators... .... .... .... .... ..... .... 140
4.15 Phase Shifters.... .... .... .... .... .... ..... .... 142
5 Microwave Tubes as Microwave Source (Oscillators)
and Amplifiers.... ..... .... .... .... .... .... ..... .... 151
5.1 Introduction. ..... .... .... .... .... .... ..... .... 152
5.2 The Conventional Tubes.... .... .... .... ..... .... 153
5.3 High-Frequency Limitations of Conventional Tubes.... 153
5.3.1 Inter-Electrode Capacitance–Shorting
the Signal.... .... .... .... .... ..... .... 153
5.3.2 Lead Inductance Impeding the Signal ... .... 154
5.3.3 Transit Time Effect Much Larger Than lW
Time Period.. .... .... .... .... ..... .... 155
5.3.4 Gain Band width Product Independent
of Frequency Becomes Limitations ..... .... 156
5.3.5 RF Losses (I2R Losses) in Wire and Skin
Effect (increasing the resistance) .. ..... .... 157
5.3.6 Dielectric Loss (Signal Power Loss) .... .... 157
5.3.7 Radiation Loss (Signal Power Loss) .... .... 157
x Contents
5.4 Microwave Tubes, Oscillators, and Amplifiers .... .... 158
5.5 Klystrons... ..... .... .... .... .... .... ..... .... 158
5.5.1 Two-Cavity Klystron Amplifier... ..... .... 158
5.5.2 Two-Cavity Klystron Oscillator... ..... .... 164
5.5.3 Reflex Klystron Oscillator ... .... ..... .... 165
5.6 Travelling Wave Tube Amplifier (TWTA) .. ..... .... 170
5.7 Backward Wave Oscillator (BWO).... .... ..... .... 178
5.8 Magnetron Oscillator... .... .... .... .... ..... .... 181
6 Microwave Semiconductors Devices: Oscillators,
Amplifiers, and Circuit .. .... .... .... .... .... ..... .... 193
6.1 Introduction. ..... .... .... .... .... .... ..... .... 195
6.2 Classification of Microwave Semiconductor Devices ... 198
6.3 Microwave Transistors—BJT and FET. .... ..... .... 198
6.3.1 Field Effect Transistors (FETs) ... ..... .... 198
6.4 Microwave Bipolar Junction Transistor (BJT)..... .... 199
6.4.1 Structure .... .... .... .... .... ..... .... 199
6.4.2 Operation.... .... .... .... .... ..... .... 200
6.4.3 Cut-off Frequency . .... .... .... ..... .... 200
6.4.4 Power Frequency Limitation . .... ..... .... 202
6.5 Junction Field Effect Transistors (Jn-FET) .. ..... .... 203
6.6 Metal–Semiconductor Field Effect Transistor
(MESFET) . ..... .... .... .... .... .... ..... .... 205
6.6.1 Physical Structure . .... .... .... ..... .... 206
6.6.2 Application of MESFET .... .... ..... .... 208
6.7 Metal Oxide Field Effect Transistor (MOSFET) ... .... 208
6.7.1 OFF-MOSFET-Enhancement Design Type ... 208
6.7.2 ON-MOSFET—Depletion Design Type.. .... 210
6.7.3 Applications.. .... .... .... .... ..... .... 210
6.8 Tunnel Diode Characteristic, and Working Oscillators
and Amplifiers ... .... .... .... .... .... ..... .... 211
6.8.1 Tunnel Diode Equivalent Circuit.. ..... .... 215
6.8.2 Tunnel Diode Amplifier and Oscillators.. .... 215
6.8.3 Applications.. .... .... .... .... ..... .... 216
6.8.4 Performance Characteristic... .... ..... .... 216
6.9 Transferred Electron Devices (TED)—Gunn Diodes.... 217
6.9.1 Introduction-Bulk Device with No
Junction. .... .... .... .... .... ..... .... 217
6.9.2 Gunn Effect: Two-Valley Theory
(Ridley–Watkins–Hilsum Theory for
dc −ve Resistance). .... .... .... ..... .... 218
6.9.3 Moving High-Field Dipole Domain in the
Device and the Phase Difference in ac
I and V . .... .... .... .... .... ..... .... 220
6.9.4 Four Modes of Gunn Device Operation as
Oscillator.... .... .... .... .... ..... .... 222
6.9.5 Diode Structure and Packaged Diode.... .... 224
6.9.6 The Gunn Diode −Ve Resistance Oscillator
and Amplifier Circuits.. .... .... ..... .... 224