microstrip filters for rf microwave applications

Microstrip Filters for RF/Microwave Applications Microstrip Filters for RF/Microwave Applications. Jia-Sheng Hong, M. J. Lancaster Copyright © 2001 John Wiley & Sons, Inc. ISBNs: 0-471-38877-7 (Hardback); 0-471-22161-9 (Electronic) Microstrip Filters for RF/Microwave Applications JIA-SHENG HONG M. J. LANCASTER A WILEY-INTERSCIENCE PUBLICATION JOHN WILEY & SONS, INC. NEW YORK / CHICHESTER / WEINHEIM / BRISBANE / SINGAPORE / TORONTO Designations used by companies to distinguish their products are often claimed as trademarks. In all instances where John Wiley & Sons, Inc., is aware of a claim, the product names appear in initial capital or ALL CAPITAL LETTERS. Readers, however, should contact the appropriate companies for more complete information regarding trademarks and registration. Copyright © 2001 by John Wiley & Sons, Inc. All rights reserved. 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ISBN 0-471-22161-9 This title is also available in print as ISBN 0-471-38877-7. For more information about Wiley products, visit our web site at www.Wiley.com. Contents Preface xi 1. Introduction 1 2. Network Analysis 7 2.1 Network Variables 7 2.2 Scattering Parameters 8 2.3 Short-Circuit Admittance Parameters 11 2.4 Open-Circuit Impedance Parameters 11 2.5 ABCD Parameters 12 2.6 Transmission Line Networks 12 2.7 Network Connections 14 2.8 Network Parameter Conversions 17 2.9 Symmetrical Network Analysis 18 2.10 Multi-Port Networks 21 2.11 Equivalent and Dual Networks 24 2.12 Multi-Mode Networks 26 References 28 3. Basic Concepts and Theories of Filters 29 3.1 Transfer Functions 29 3.1.1 General Definitions 29 3.1.2 The Poles and Zeros on the Complex Plane 30 3.1.3 Butterworth (Maximally Flat) Response 31 3.1.4 Chebyshev Response 32 3.1.5 Elliptic Function Response 34 3.1.6 Gaussian (Maximally Flat Group-Delay) Response 36 v 3.1.7 All-Pass Response 37 3.2 Lowpass Prototype Filters and Elements 38 3.2.1 Butterworth Lowpass Prototype Filters 41 3.2.2 Chebyshev Lowpass Prototype Filters 41 3.2.3 Elliptic Function Lowpass Prototype Filters 44 3.2.4 Gaussian Lowpass Prototype Filters 46 3.2.5 All-Pass Lowpass Prototype Filters 47 3.3 Frequency and Element Transformations 48 3.3.1 Lowpass Transformation 49 3.3.2 Highpass Transformation 51 3.3.3 Bandpass Transformation 51 3.3.4 Bandstop Transformation 53 3.4 Immittance Inverters 54 3.4.1 Definition of Immittance, Impedance and Admittance Inverters 54 3.4.2 Filters with Immittance Inverters 56 3.4.3 Practical Realization of Immittance Inverters 60 3.5 Richards’ Transformation and Kuroda Identities 61 3.5.1 Richards’ Transformation 61 3.5.2 Kuroda Identities 66 3.5.3 Coupled-Line Equivalent Circuits 66 3.6 Dissipation and Unloaded Quality Factor 69 3.6.1 Unloaded Quality Factors of Lossy Reactive Elements 70 3.6.2 Dissipation Effects on Lowpass and Highpass Filters 71 3.6.3 Dissipation Effects on Bandpass and Bandstop Filters 73 References 75 4. Transmission Lines and Components 77 4.1 Microstrip Lines 77 4.1.1 Microstrip Structure 77 4.1.2 Waves in Microstrip 77 4.1.3 Quasi-TEM Approximation 78 4.1.4 Effective Dielectric Constant and Characteristic Impedance 78 4.1.5 Guided Wavelength, Propagation Constant, Phase 4.1.5 Velocity, and Electrical Length 80 4.1.6 Synthesis of W/h 80 4.1.7 Effect of Strip Thickness 81 4.1.8 Dispersion in Microstrip 82 4.1.9 Microstrip Losses 83 4.1.10 Effect of Enclosure 84 4.1.11 Surface Waves and Higher-Order Modes 84 4.2 Coupled Lines 84 4.2.1 Even- and Odd-Mode Capacitances 85 4.2.2 Even- and Odd-Mode Characteristic Impedances and Effective 4.1.5 Dielectric Constants 87 4.2.3 More Accurate Design Equations 87 vi CONTENTS 4.3 Discontinuities and Components 89 4.3.1 Microstrip Discontinuities 89 4.3.2 Microstrip Components 93 4.3.3 Loss Considerations for Microstrip Resonators 102 4.4 Other Types of Microstrip Lines 104 References 106 5. Lowpass and Bandpass Filters 109 5.1 Lowpass Filters 109 5.1.1 Stepped-Impedance L-C Ladder Type Lowpass Filters 109 5.1.2 L-C Ladder Type of Lowpass Filters using Open-Circuited Stubs 112 5.1.3 Semilumped Lowpass Filters Having Finite-Frequency 5.1.3 Attenuation Poles 116 5.2 Bandpass Filters 121 5.2.1 End-Coupled, Half-Wavelength Resonator Filters 121 5.2.2 Parallel-Coupled, Half-Wavelength Resonator Filters 127 5.2.3 Hairpin-Line Bandpass Filters 129 5.2.4 Interdigital Bandpass Filters 133 5.2.5 Combline Filters 142 5.2.6 Pseudocombline Filters 148 5.2.7 Stub Bandpass Filters 151 References 158 6. Highpass and Bandstop Filters 161 6.1 Highpass Filters 161 6.1.1 Quasilumped Highpass Filters 161 6.1.2 Optimum Distributed Highpass Filters 165 6.2 Bandstop Filters 168 6.2.1 Narrow-Band Bandstop Filters 168 6.2.2 Bandstop Filters with Open-Circuited Stubs 176 6.2.3 Optimum Bandstop Filters 182 6.2.4 Bandstop Filters for RF Chokes 188 References 190 7. Advanced Materials and Technologies 191 7.1 Superconducting Filters 191 7.1.1 Superconducting Materials 191 7.1.2 Complex Conductivity of Superconductors 192 7.1.3 Penetration Depth of Superconductors 193 7.1.4 Surface Impedance of Superconductors 194 7.1.5 Nonlinearity of Superconductors 197 7.1.6 Substrates for Superconductors 199 7.1.7 HTS Microstrip Filters 200 7.1.8 High-Power HTS Filters 201 7.2 Ferroelectric Tunable Filters 204 CONTENTS vii 7.2.1 Ferroelectric Materials 205 7.2.2 Dielectric Properties 206 7.2.3 Tunable Microstrip Filters 208 7.3 Micromachined Filters 211 7.3.1 MEMS and Micromachining 211 7.3.2 Micromachined Microstrip Filters 211 7.4 MMIC Filters 215 7.4.1 MMIC Technology 215 7.4.2 MMIC Microstrip Filters 216 7.5 Active Filters 217 7.5.1 Active Filter Methodologies 217 7.5.2 Active Microstrip Filters 219 7.6 Photonic Bandgap (PBG) Filters 221 7.6.1 PBG Structures 221 7.6.2 PBG Microstrip Filters 222 7.7 Low-Temperature Cofired Ceramic (LTCC) Filters 224 7.7.1 LTCC Technology 224 7.7.2 Miniaturized LTCC Filters 225 References 227 8. Coupled Resonator Circuits 235 8.1 General Coupling Matrix for Coupled-Resonator Filters 236 8.1.1 Loop Equation Formulation 236 8.1.2 Node Equation Formulation 240 8.1.3 General Coupling Matrix 243 8.2 General Theory of Couplings 244 8.2.1 Synchronously Tuned Coupled-Resonator Circuits 245 8.2.2 Asynchronously Tuned Coupled-Resonator Circuits 251 8.3 General Formulation for Extracting Coupling Coefficient k 257 8.4 Formulation for Extracting External Quality Factor Q e 258 8.4.1 Singly Loaded Resonator 259 8.4.2 Doubly Loaded Resonator 262 8.5 Numerical Examples 264 8.5.1 Extracting k (Synchronous Tuning) 265 8.5.2 Extracting k (Asynchronous Tuning) 267 8.5.3 Extracting Q e 270 References 271 9. CAD for Low-Cost and High-Volume Production 273 9.1 Computer-Aided Design Tools 274 9.2 Computer-Aided Analysis 274 9.2.1 Circuit Analysis 274 9.2.2 Electromagnetic Simulation 279 9.2.3 Artificial Neural Network Modeling 283 viii CONTENTS 9.3 Optimization 285 9.3.1 Basic Concepts 285 9.3.2 Objective Functions for Filter Optimization 286 9.3.3 One-Dimensional Optimization 288 9.3.4 Gradient Methods for Optimization 288 9.3.5 Direct Search Optimization 291 9.3.6 Optimization Strategies Involving EM Simulations 295 9.4 Filter Synthesis by Optimization 299 9.4.1 General Description 299 9.4.2 Synthesis of a Quasielliptic Function Filter by Optimization 299 9.4.3 Synthesis of an Asynchronously Tuned Filter by Optimization 300 9.4.4 Synthesis of a UMTS Filter by Optimization 302 9.5 CAD Examples 306 References 312 10. Advanced RF/Microwave Filters 315 10.1 Selective Filters with a Single Pair of Transmission Zeros 315 10.1.1 Filter Characteristics 315 10.1.2 Filter Synthesis 317 10.1.3 Filter Analysis 320 10.1.4 Microstrip Filter Realization 321 10.2 Cascaded Quadruplet (CQ) Filters 325 10.2.1 Microstrip CQ Filters 326 10.2.2 Design Example 326 10.3 Trisection and Cascaded Trisection (CT) Filters 328 10.3.1 Characteristics of CT Filters 328 10.3.2 Trisection Filters 331 10.3.3 Microstrip Trisection Filters 335 10.3.4 Microstrip CT Filters 340 10.4 Advanced Filters with Transmission Line Inserted Inverters 341 10.4.1 Characteristics of Transmission Line Inserted Inverters 341 10.4.2 Filtering Characteristics with Transmission Line Inserted Inverters 344 10.4.3 General Transmission Line Filter 348 10.5 Linear Phase Filters 350 10.5.1 Prototype of Linear Phase Filter 350 10.5.2 Microstrip Linear Phase Bandpass Filters 355 10.6 Extract Pole Filters 359 10.6.1 Extracted Pole Synthesis Procedure 360 10.6.2 Synthesis Example 366 10.6.3 Microstrip Extracted Pole Bandpass Filters 368 10.7 Canonical Filters 371 10.7.1 General Coupling Structure 371 10.7.2 Elliptic Function/Selective Linear Phase Canonical Filters 373 References 375 CONTENTS ix 11. Compact Filters and Filter Miniaturization 379 11.1 Ladder Line Filters 379 11.1.1 Ladder Microstrip Line 379 11.1.2 Ladder Microstrip Line Resonators and Filters 381 11.2 Pseudointerdigital Line Filters 383 11.2.1 Filtering Structure 383 11.2.2 Pseudointerdigital Resonators and Filters 385 11.3 Miniature Open-Loop and Hairpin Resonator Filters 389 11.4 Slow-Wave Resonator Filters 392 11.4.1 Capacitively Loaded Transmission Line Resonator 392 11.4.2 End-Coupled Slow-Wave Resonator Filters 396 11.4.3 Slow-Wave, Open-Loop Resonator Filters 396 11.5 Miniature Dual-Mode Resonator Filters 404 11.5.1 Microstrip Dual-Mode Resonators 404 11.5.2 Miniaturized Dual-Mode Resonator Filters 408 11.6 Multilayer Filters 410 11.6.1 Wider-Band Multilayer Filters 411 11.6.2 Narrow-Band Multilayer Filters 412 11.7 Lumped-Element Filters 420 11.8 Miniaturized Filters Using High Dielectric Constant Substrates 426 References 428 12. Case Study for Mobile Communications Applications 433 12.1 HTS Subsystems and RF Modules for Mobile Base Stations 433 12.2 HTS Microstrip Duplexers 436 12.2.1 Duplexer Principle 438 ` 12.2.2 Duplexer Design 439 12.2.3 Duplexer Fabrication and Test 444 12.3 Preselect HTS Microstrip Bandpass Filters 446 12.3.1 Design Considerations 446 12.3.2 Design of the Preselect Filter 448 12.3.3 Sensitivity Analysis 448 12.3.4 Evaluation of Quality Factor 450 12.3.5 Filter Fabrication and Test 454 References 456 Appendix: Useful Constants and Data 459 Index 461 x CONTENTS Preface Filters play important roles in many RF/microwave applications. Emerging applica- tions such as wireless communications continue to challenge RF/microwave filters with ever more stringent requirements—higher performance, smaller size, lighter weight, and lower cost. The recent advances in novel materials and fabrication tech- nologies, including high-temperature superconductors (HTS), low-temperature cofired ceramics (LTCC), monolithic microwave integrated circuits (MMIC), mi- croelectromechanic system (MEMS), and micromachining technology, have stimu- lated the rapid development of new microstrip and other filters for RF/microwave applications. In the meantime, advances in computer-aided design (CAD) tools such as full-wave electromagnetic (EM) simulators have revolutionized filter de- sign. Many novel microstrip filters with advanced filtering characteristics have been demonstrated. However, up until now there has not been a single book dedicated to this subject. Microstrip Filters for RF/Microwave Applications offers a unique and compre- hensive treatment of RF/microwave filters based on the microstrip structure, provid- ing a link to applications of computer-aided design tools and advanced materials and technologies. Many novel and sophisticated filters using computer-aided design are discussed, from basic concepts to practical realizations. The book is self-con- tained—it is not only a valuable design resource but also a handy reference for stu- dents, researchers, and engineers in microwave engineering. It can also be used for RF/microwave education. The outstanding features of this book include discussion of many novel mi- crostrip filter configurations with advanced filtering characteristics, new design techniques, and methods for filter miniaturization. The book emphasizes computer analysis and synthesis and full-wave electromagnetic (EM) simulation through a large number of design examples. Applications of commercially available software are demonstrated. Commercial applications are included as are design theories and xi [...]... pole filters, 359 See also Advanced RF/ microwave filters synthesis, 359 Extracting coupling coefficient, 257 Extracting external quality Factor, 258 Feasible solution, 286 Feed line, 258 Feedback, 218 Ferroelectric(s), 204 materials, 205 thin films, 205 Field vectors, 244 Filter, see also Advanced RF/ microwave filters, Bandpass filters, Bandstop filters, Compact filters, Highpass filters, Lowpass filters. .. design equations for microstrip lines, coupled microstrip lines, and discontinuities, as well as lumped and distributed components, which are useful for design of filters In Chapter 5, conventional microstrip lowpass and bandpass filters, such as stepped-impedance filters, open-stub filters, semilumped element filters, end- and parallel-coupled half-wavelength resonator filters, hairpin-line filters, interdigital... importance for design of RF/ microwave filters, in particular the narrow-band bandpass filters, which play a significant role in many applications There is a general technique for designing coupled resonator filters, which can be applied to any type of resonator despite its physical structure For example, it can be applied to the design of waveguide filters, dielectric resonator filters, ceramic combline filters, ... dual-mode filters, multilayer filters, lumped-element filters, and filters using high-dielectric constant substrates The final chapter of the book (Chapter 12) presents a case study of high-temperature superconducting (HTS) microstrip filters for cellular base station applications The study starts with a brief discussion of typical HTS subsystems and RF modules that include HTS microstrip filters for cellular... clarity, 434 Canonical filters, 371 See also Advanced RF/ microwave filters Canonical form, 371 Capacitance per unit length, 78 Capacitively loaded transmission line(s), 381 resonator, 392 Cascade connection, 15 Cascaded couplings, 371 Cascaded network, 275 Cascaded quadruplet (CQ) filters, 325 See also Advanced RF/ microwave filters Cascaded trisection (CT) filters, 328 Cauer filters, 35 Cavity modes,... and combline filters, pseudocombline filters and stub-line filters, are discussed with instructive design examples Chapter 6 discusses some typical microstrip highpass and bandstop filters These include quasilumped element and optimum distributed highpass filters, narrowband and wide-band bandstop filters, as well as filters for RF chokes Design equations, tables and examples are presented for easy references... some advanced filters, including selective filters with a single pair of transmission zeros, cascaded quadruplet (CQ) filters, trisection and cascaded trisection (CT) filters, cross-coupled filters using transmission line inserted inverters, linear phase filters for group delay equalization, and extracted-pole filters These types of filters, which are different from conventional Chebyshev filters, must... book are not only for microstrip filters but directly applicable to other types of filters, such as waveguide filters Although the physical realization of filters at RF/ microwave frequencies may vary, the circuit network topology is common to all Therefore, the technique content of the book begins with Chapter 2, which describes various network concepts and equations; theses are useful for the analysis... ANALOG INTEGRATED CIRCUIT DESIGN ț Ravender Goyal (ed.) MICROSTRIP FILTERS FOR RF/ MICROWAVE APPLICATIONS ț Jia-Sheng Hong and M J Lancaster MICROWAVE APPROACH TO HIGHLY IRREGULAR FIBER OPTICS ț Huang Hung-Chia NONLINEAR OPTICAL COMMUNICATION NETWORKS ț Eugenio Iannone, Francesco Matera, Antonio Mecozzi, and Marina Settembre FINITE ELEMENT SOFTWARE FOR MICROWAVE ENGINEERING ț Tatsuo Itoh, Giuseppe Pelosi... optical spectrum, the ultraviolet spectrum, and x-rays Below the microwave frequency spectrum is the radio frequency (RF) spectrum The frequency boundary between RF and microwaves is somewhat arbitrary, depending on the particular technologies developed for the exploitation of that specific frequency range Therefore, by extension, the RF/ microwave applications can be referred to as communications, radar, . Microstrip Filters for RF/ Microwave Applications Microstrip Filters for RF/ Microwave Applications. Jia-Sheng Hong, M. J. Lancaster Copyright. subject. Microstrip Filters for RF/ Microwave Applications offers a unique and compre- hensive treatment of RF/ microwave filters based on the microstrip structure, provid- ing a link to applications. also Advanced RF/ microwave filters, Bandpass filters, Bandstop filters, Compact filters, Highpass filters, Lowpass filters analysis, 320 miniaturization, 379. See also Compact filters networks,