# RF and Microwave Circuit Design

## Theory and Applications

Microwave and Wireless Technologies Series

1. Edition October 2021

528 Pages, Hardcover*Wiley & Sons Ltd*

**978-1-119-11463-5**

RF and Microwave Circuit Design

Provides up-to-date coverage of the fundamentals of high-frequency microwave technology, written by two leading voices in the field

RF and Microwave Circuit Design: Theory and Applications is an authoritative, highly practical introduction to basic RF and microwave circuits. With an emphasis on real-world examples, the text explains how distributed circuits using microstrip and other planar transmission lines can be designed and fabricated for use in modern high-frequency passive and active circuits and sub-systems. The authors provide clear and accurate guidance on each essential aspect of circuit design, from the theory of transmission lines to the passive and active circuits that form the basis of modern high-frequency circuits and sub-systems.

Assuming a basic grasp of electronic concepts, the book is organized around first principles and includes an extensive set of worked examples to guide student readers with no prior grounding in the subject of high-frequency microwave technology. Throughout the text, detailed coverage of practical design using distributed circuits demonstrates the influence of modern fabrication processes. Filling a significant gap in literature by addressing RF and microwave circuit design with a central theme of planar distributed circuits, this textbook:

* Provides comprehensive discussion of the foundational concepts of RF and microwave transmission lines introduced through an exploration of wave propagation along a typical transmission line

* Describes fabrication processes for RF and microwave circuits, including etched, thick-film, and thin-film RF circuits

* Covers the Smith Chart and its application in circuit design, S-parameters, Mason???s non-touching loop rule, transducer power gain, and stability

* Discusses the influence of noise in high-frequency circuits and low-noise amplifier design

* Features an introduction to the design of high-frequency planar antennas

* Contains supporting chapters on fabrication, circuit parameters, and measurements

* Includes access to a companion website with PowerPoint slides for instructors, as well as supplementary resources

Perfect for senior undergraduate students and first-year graduate students in electrical engineering courses, RF and Microwave Circuit Design: Theory and Applications will also earn a place in the libraries of RF and microwave professionals looking for a useful reference to refresh their understanding of fundamental concepts in the field.

1. RF Transmission lines

1.0 Introduction

1.1 Voltage, current and impedance relationships on a transmission line

1.2 Propagation constant

1.2.1 Dispersion

1.2.2 Amplitude distortion

1.3 Lossless transmission lines

1.4 Matched and mismatched transmission lines

1.5 Waves on a transmission line

1.6 The Smith chart

1.6.1 Derivation of the chart

1.6.2 Properties of the chart

1.7 Stubs

1.8 Distributed matching circuits

1.9 Manipulation of lumped impedance using the Smith chart

1.10 Lumped impedance matching

1.10.1 Matching a complex load impedance to a real source impedance

1.10.2 Matching a complex load impedance to a complex source impedance

1.11 Equivalent lumped circuit of a lossless transmission line

1.12 Supplementary problems

1.13 Appendices

Appendix A1.1 Coaxial cable

A1.1.1 Electromagnetic field patterns in coaxial cable

A1.1.2 Essential properties of coaxial cables

Appendix A1.2 Coplanar waveguide

A1.2.1 Structure of coplanar waveguide (CPW)

A1.2.2 Electromagnetic field distribution on a CPW line

A1.2.3 Essential properties of coplanar (CPW) lines

A1.2.4 Summary of key points relating to CPW lines

Appendix A1.3 Metal waveguide

A1.3.1 Waveguide principles

A1.3.2 Waveguide propagation

A1.3.3 Rectangular waveguide modes

A1.3.4 The waveguide equation

A1.3.5 Phase and group velocities

A1.3.6 Field theory analysis of rectangular waveguides

A1.3.7 Waveguide impedance

A1.3.8 Higher-order rectangular waveguide modes

A1.3.9 Waveguide attenuation

A1.3.10 Sizes of rectangular waveguide, and waveguide designation

A1.3.11 Circular waveguide

Appendix A1.4 Microstrip

Appendix A1.5 Equivalent lumped circuit representation of a transmission line

References

2. Planar Circuit Design I: Designing using Microstrip

2.0 Introduction

2.1 Electromagnetic field distribution across a microstrip line

2.2 Effective relative permittivity,

2.3 Microstrip design graphs and CAD software

2.4 Operating frequency limitations

2.5 Skin depth

2.6 Examples of microstrip components

2.6.1 Branch-line coupler

2.6.2 Quarter-wave transformer

2.6.3 Wilkinson power divider

2.7 Microstrip coupled-line structures

2.7.1 Analysis of microstrip coupled lines

2.7.2 Microstrip directional couplers

2.7.2.1 Design of microstrip directional couplers

2.7.2.2 Directivity of microstrip directional couplers

2.7.2.3 Improvements to microstrip directional couplers

2.7.3 Examples of other common microstrip coupled-line structures

2.7.3.1 Microstrip DC break

2.7.3.2 Edge-coupled microstrip band-pass filter

2.7.3.3 Lange coupler

2.8 Summary

2.9 Supplementary problems

2.10 Appendix A2.1: Microstrip design graphs

References

3. Fabrication processes for RF and microwave circuits

3.1 Introduction

3.2 Review of essential materials parameters

3.2.1 Dielectrics

3.2.2 Conductors

3.3 Requirements for RF circuit materials

3.4 Fabrication of planar high-frequency circuits

3.4.1 Etched circuits

3.4.2 Thick-film circuits (direct screen printed)

3.4.3 Thick-film circuits (using photoimageable materials)

3.4.4 LTCC (low temperature co-fired ceramic) circuits

3.4.5 Use of ink jet technology

3.5 Characterization of materials for RF and microwave circuits

3.5.1 Measurement of dielectric loss and dielectric constant

3.5.1.1 Cavity resonators

3.5.1.2 Dielectric characterization by cavity perturbation

3.5.1.3 Use of the split post dielectric resonator (SPDR)

3.5.1.4 Open-resonator

3.5.1.5 Free-space transmission measurements

3.5.2 Measurement of planar line properties

3.5.2.1 The microstrip resonant ring

3.5.2.2 Non-resonant lines

3.5.3 Physical properties of microstrip lines

3.6 Supplementary problems

references

4. Planar Circuit Design II: Refinements to basic designs

4.1 Introduction

4.2 Discontinuities in microstrip

4.2.1 Open-end effect

4.2.2 Step width

4.2.3 Corners

4.2.4 Gaps

4.2.5 T-junctions

4.3 Microstrip enclosures

4.4 Packaged lumped-element passive components

4.4.1 Typical packages for RF passive components

4.4.2 Lumped-element resistors

4.4.3 Lumped-element capacitors

4.4.4 Lumped-element inductors

4.5 Miniature planar components

4.5.1 Spiral inductors

4.5.2 Loop inductors

4.5.3 Interdigitated capacitors

4.5.4 MIM (metal-insulator-metal) capacitors

4.6 Appendix 4.1: Insertion loss due to a microstrip gap

References

5. S-parameters

5.1 Introduction

5.2 S-parameter definitions

5.3 Signal flow graphs

5.4 Mason's non-touching loop rule

5.5 Reflection coefficient of a 2-port network

5.6 Power gains of two-port networks

5.7 Stability

5.8 Supplementary Problems

5.9 Appendix A5.1 Relationships between network parameters

A5.1.1 Transmission parameters (ABCD parameters)

A5.1.2 Admittance parameters (Y-parameters)

A5.1.3 Impedance parameters (Z-parameters)

References

6. Microwave Ferrites

6.1 Introduction

6.2 Basic properties of ferrite materials

6.2.1 Ferrite materials

6.2.2 Precession in ferrite materials

6.2.3 Permeability tensor

6.2.4 Faraday rotation

6.3 Ferrites in metallic waveguide

6.3.1 Resonance isolator

6.3.2 Field displacement isolator

6.3.3 Waveguide circulator

6.4 Ferrites in planar circuits

6.4.1 Planar circulators

6.4.2 Edge-guided-mode propagation

6.4.3 Edge-guided-mode isolator

6.4.4 Phase shifters

6.5 Self-biased ferrites

6.6 Supplementary problems

References

7. Measurements

7.1 Introduction

7.2 RF and Microwave connectors

7.2.1 Maintenance of connectors

7.2.2 Connecting to planar circuits

7.3 Microwave vector network analyzers

7.3.1 Description and configuration

7.3.2 Error models representing a VNA

7.3.3 Calibration of a VNA

7.4 On-wafer measurements

7.5 Summary

References

8. RF Filters

8.1 Introduction

8.2 Review of filter responses

8.3 Filter parameters

8.4 Design strategy for RF and microwave filters

8.5 Multi-element low-pass filter

8.6 Practical filter responses

8.7 Butterworth (or maximally-flat) response

8.7.1 Butterworth low-pass filter

8.7.3 Butterworth band-pass filter

8.7.3 Butterworth band-pass filter

8.8 Chebyshev (equal ripple) response

8.9 Microstrip low-pass filter, using stepped impedances

8.10 Microstrip low-pass filter, using stubs

8.11 Microstrip edge-coupled band-pass filters

8.12 Microstrip end-coupled band-pass filters

8.13 Practical points associated with filter design

8.14 Summary

8.15 Supplementary problems

8.16 Appendix A8.1 Equivalent lumped T-network representation of a transmission line

References

9. Microwave Small-Signal Amplifiers

9.1 Introduction

9.2 Conditions for matching

9.3 Distributed (microstrip) matching networks

9.4 DC biasing circuits

9.5 Microwave transistor packages

9.6 Typical hybrid amplifier

9.7 DC finger breaks

9.8 Constant gain circles

9.9 Stability circles

9.10 Noise circles

9.11 Low-noise amplifier design

9.12 Simultaneous conjugate match

9.13 Broadband matching

9.14 Summary

9.15 Supplementary problems

References

10. Switches and Phase Shifters

10.1 Introduction

10.2 Switches

10.2.1 PIN diodes

10.2.2 FETs (Field Effect Transistors)

10.2.3 MEMS (Microelectromechanical Systems)

10.2.4 IPCS (Inline Phase Change Switch) devices

10.3 Digital phase shifters

10.3.1 Switched-path phase shifter

10.3.2 Loaded-line phase shifter

10.3.3 Reflection-type phase shifter

10.3.4 Schiffman 90° phase shifter

10.3.5 Single switch phase shifter

10.4 Supplementary problems

References

11. Oscillators

11.1 Introduction

11.2 Criteria for oscillation in a feedback circuit

11.3 RF (transistor) oscillators

11.3.1 Colpitts oscillator

11.3.2 Hartley Oscillator

11.3.3 Clapp-Gouriet Oscillator

11.4 Voltage controlled oscillator (VCO)

11.5 Crystal-controlled oscillators

11.5.1 Crystals

11.5.2 Crystal-controlled oscillators

11.6 Frequency synthesizers

11.6.1 The phase-locked loop

11.6.1.1 Principle of a phase-locked loop

11.6.1.2 Main components of a phase-locked loop

11.6.1.3 Gain of a phase-locked loop

11.6.1.4 Transient analysis of a phase-locked loop

11.6.2 Indirect frequency synthesizer circuits

11.7 Microwave oscillators

11.7.1 Dielectric resonator oscillator

11.7.2 Delay line stabilized oscillator

11.7.3 Diode oscillators

11.7.3.1 Gunn diode oscillator

11.7.3.2 IMPATT diode oscillator

11.8 Oscillator noise

11.9 Measurement of oscillator noise

11.10 Supplementary problems

References

12. RF and Microwave Antennas

12.1 Introduction

12.2 Antenna parameters

12.3 Spherical polar coordinates

12.4 Radiation from a Hertzian dipole

12.4.1 Basic principles

12.4.2 Gain of a Hertzian dipole

12.5 Radiation from a half-wave dipole

12.5.1 Basic principles

12.5.2 Gain of a half-wave dipole

12.5.3 Summary of the properties of a half-wave dipole

12.6 Antenna arrays

12.7 Mutual impedance

12.8 Arrays containing parasitic elements

12.9 Yagi-Uda array

12.10 Log-periodic array

12.11 Loop antenna

12.12 Planar antennas

12.12.1 Linearly polarized patch antennas

12.12.2 Circularly polarized planar antennas

12.13 Horn antennas

12.14 Parabolic reflector antennas

12.15 Slot radiators

12.16 Supplementary problems

12.17 Appendix: Microstrip design graphs for substrates with r = 2.3

References

13. Power Amplifiers and Distributed Amplifiers

13.1 Introduction

13.2 Power amplifiers

13.2.1 Overview of power amplifier parameters

13.2.1.1 Power gain

13.2.1.2 Power added efficiency (PAE)

13.2.1.3 Input and output impedances

13.2.2 Distortion

13.2.2.1 Gain compression

13.2.2.2 Third-order intercept point

13.2.3 Linearization

13.2.3.1 Pre-distortion

13.2.3.2 Negative feedback

13.2.3.3 Feedforward

13.2.4 Power combining

13.2.5 Doherty amplifier

13.3 Load matching of power amplifiers

13.4 Distributed amplifiers

13.4.1 Description and principle of operation

13.4.2 Analysis

13.5 Developments in materials and packaging for power amplifiers

References

14. Receivers and Sub-Systems

14.1 Introduction

14.2 Receiver noise sources

14.2.1 Thermal noise

14.2.2 Semiconductor noise

14.3 Noise measures

14.3.1 Noise figure (F)

14.3.2 Noise temperature (Te)

14.4 Noise figure of cascaded networks

14.5 Antenna noise temperature

14.6 System noise temperature

14.7 Noise figure of a matched attenuator

14.8 Superhet receiver

14.8.1 Single-conversion superhet receiver

14.8.2 Image frequency

14.8.3 Key figures-of-merit for a superhet receiver

14.8.4 Double-conversion superhet receiver

14.8.5 Noise budget graph for a superhet receiver

14.9 Mixers

14.9.1 Basic mixer principles

14.9.2 Mixer parameters

14.9.3 Active and passive mixers

14.9.4 Single-ended diode mixer

14.9.5 Single balanced mixer

14.9.6 Double balanced mixer

14.9.7 Active FET mixers

14.10 Supplementary problems

14.11 Appendices

Appendix A14.1 Error function table

Appendix A14.2 Measurement of noise figure

References

Answers to selected supplementary problems

Professor Colin S. Aitchison was previously Chair of the European Microwave Conference and has contributed to approximately 185 scholarly publications. He was formerly Dean of the Technology faculty at Brunel University, United Kingdom.