Foreword to the First Edition .................................. xv
Preface to the Second Edition ................................ xvii
Preface to the First Edition .................................. xxi
CHAPTER 1
Introduction .................................................... 1
1.1 Coupled Structures .......................................... 1
1.1.1 Types of Coupled Structures ........................... 3
1.1.2 Coupling Mechanism .................................... 4
1.2 Components Based on Coupled Structures ...................... 6
1.2.1 Directional Couplers .................................. 6
1.2.2 Filters ............................................... 8
1.3 Applications ............................................... 11
1.4 Scope of the Book .......................................... 13
References ................................................. 13
CHAPTER 2
Microwave Network Theory ....................................... 17
2.1 Actual and Equivalent Voltages and Currents ................ 17
2.1.1 Normalized Voltages and Currents ..................... 18
2.1.2 Unnormalized Voltages and Currents ................... 21
2.1.3 Reflection Coefficient, VSWR, and Input Impedance .... 22
2.1.4 Quantities Required to Describe the State of
a Transmission Line .................................. 24
2.2 Impedance and Admittance Matrix Representation of
a Network .................................................. 26
2.2.1 Impedance Matrix ..................................... 26
2.2.2 Admittance Matrix .................................... 27
2.2.3 Properties of Impedance and Admittance Parameters
of a Passive Network ................................. 27
2.3 Scattering Matrix .......................................... 28
2.3.1 Unitary Property ..................................... 30
2.3.2 Transformation with Change in Position of Terminal
Planes ............................................... 31
2.3.3 Reciprocal Networks .................................. 32
2.3.4 Relationship Between Normalized and Unnormalized
Matrices ............................................. 32
2.4 Special Properties of Two-, Three-, and Four-Port
Passive, Lossless Networks ................................. 32
2.4.1 Two-Port Networks .................................... 33
2.4.2 Three-Port Reciprocal Networks ....................... 34
2.4.3 Three-Port Nonreciprocal Networks .................... 35
2.4.4 Four-Port Reciprocal Networks ........................ 36
2.5 Special Representation of Two-Port Networks ................ 38
2.5.1 ABCD Parameters ...................................... 38
2.5.2 Reflection and Transmission Coefficients in Terms
of ABCD Parameters ................................... 40
2.5.3 Equivalent T and Π Networks of Two-Port Circuits ..... 41
2.6 Conversion Relations ....................................... 43
2.7 Scattering Matrix of Interconnected Networks ............... 45
2.7.1 Scattering Parameters of Reduced Networks ............ 47
2.7.2 Reduction of a Three-Port Network into a Two-Port
Network .............................................. 48
2.7.3 Reduction of a Two-Port Network into a One-Port
Network .............................................. 49
2.7.4 Reduction of a Four-Port Network into a Two-Port
Network .............................................. 50
References ................................................. 51
CHAPTER 3
Characteristics of Planar Transmission Lines ................... 53
3.1 General Characteristics of TEM and Quasi-TEM Modes ......... 53
3.1.1 TEM Modes ............................................ 57
3.1.2 Quasi-TEM Modes ...................................... 58
3.1.3 Skin Depth and Surface Impedance of Imperfect
Conductors ........................................... 59
3.1.4 Conductor Loss of TEM and Quasi-TEM Modes ............ 60
3.2 Representation of Capacitances of Coupled Lines ............ 61
3.2.1 Even- and Odd-Mode Capacitances of Symmetrical
Coupled Lines ........................................ 62
3.2.2 Parallel-Plate and Fringing Capacitances of Single
and Coupled Planar Transmission Lines ................ 66
3.3 Characteristics of Single and Coupled Striplines ........... 68
3.3.1 Single Stripline ..................................... 69
3.3.2 Edge-Coupled Striplines .............................. 73
3.4 Characteristics of Single and Coupled Microstrip Lines ..... 74
3.4.1 Single Microstrip .................................... 75
3.4.2 Coupled Microstrip Lines ............................. 81
3.5 Single and Coupled Coplanar Waveguides ..................... 83
3.5.1 Coplanar Waveguide ................................... 84
3.5.2 Coplanar Waveguide with Upper Shielding .............. 86
3.5.3 Conductor-Backed Coplanar Waveguide with Upper
Shielding ............................................ 87
3.5.4 Coupled Coplanar Waveguides .......................... 88
3.6 Suspended and Inverted Microstrip Lines .................... 88
3.7 Broadside-Coupled Lines .................................... 93
3.7.1 Broadside-Coupled Striplines ......................... 94
3.7.2 Broadside-Coupled Suspended Microstrip Lines ......... 95
3.7.3 Broadside-Coupled Offset Striplines .................. 96
3.8 Slot-Coupled Microstrip Lines .............................. 99
References ................................................ 102
CHAPTER 4
Analysis of Uniformly Coupled Lines ........................... 105
4.1 Even- and Odd-Mode Analysis of Symmetrical Networks ....... 106
4.1.1 Even-Mode Excitation ................................ 108
4.1.2 Odd-Mode Excitation ................................. 109
4.2 Directional Couplers Using Uniform Coupled Lines .......... 111
4.2.1 Forward-Wave (or Codirectional) Directional
Couplers ............................................ 114
4.2.2 Ba ckward-Wave Directional Couplers ................. 116
4.3 Uniformly Coupled Asymmetrical Lines ...................... 120
4.3.1 Parameters of Asymmetrical Coupled Lines ............ 121
4.3.2 Distributed Equivalent Circuit of Coupled Lines ..... 126
4.3.3 Relation Between Normal Mode (c and π) and
Distributed Line Parameters ......................... 130
4.3.4 Approximate Distributed Line or Normal-Mode
Parameters of Asymmetrical Coupled Lines ............ 132
4.4 Directional Couplers Using Asymmetrical Coupled Lines ..... 133
4.4.1 Forward-Wave Directional Couplers ................... 133
4.4.2 Backward-Wave Directional Couplers .................. 136
4.5 Design of Multilayer Couplers ............................. 138
4.5.1 Determination of Capacitance and Inductance
Parameters Using Sonnet Lite ........................ 139
4.5.2 Coupler Design ...................................... 140
References ................................................ 147
CHAPTER 5
Broadband Forward-Wave Directional Couplers ................... 149
5.1 Forward-Wave Directional Couplers ......................... 150
5.1.1 3-dB Coupler Using Symmetrical Microstrip Lines ..... 151
5.1.2 Design and Performance of 3-dB Asymmetrical
Couplers ............................................ 153
5.1.3 Ultra-Broadband Forward-Wave Directional Couplers ... 155
5.2 Coupled-Mode Theory ....................................... 156
5.2.1 Nature of Coupling Coefficient K12 and K21 ........... 158
5.2.2 Waves on Lines 1 and 2 in the Presence of
Coupling ............................................ 158
5.2.3 Coupled-Mode Theory and Even- and Odd-Mode
Analysis ............................................ 160
5.2.4 Coupling Between Asymmetrical Lines ................. 161
5.3 Coupled-Mode Theory for Weakly Coupled Resonators ......... 163
References ................................................ 165
CHAPTER 6
Parallel-Coupled TEM Directional Couplers ..................... 167
6.1 Coupler Parameters ........................................ 167
6.2 Single-Section Directional Coupler ........................ 169
6.2.1 Frequency Response .................................. 169
6.2.2 Design .............................................. 171
6.2.3 Compact Couplers .................................... 176
6.2.4 Equivalent Circuit of a Quarter-Wave Coupler ........ 176
6.3 Multisection Directional Couplers ......................... 177
6.3.1 Theory and Synthesis ................................ 177
6.3.2 Limitations of Multisection Couplers ................ 184
6.4 Techniques to Improve Directivity of Microstrip
Couplers .................................................. 186
6.4.1 Lumped Compensation ................................. 186
6.4.2 Use of Dielectric Overlays .......................... 189
6.4.3 Use of Wiggly Lines ................................. 189
6.4.4 Other Techniques .................................... 192
References ................................................ 194
CHAPTER 7
Nonuniform Broadband TEM Directional Couplers ................. 197
7.1 Symmetrical Couplers ...................................... 197
7.1.1 Coupling in Terms of Even-Mode Characteristic
Impedance ........................................... 199
7.1.2 Synthesis ........................................... 201
7.1.3 Technique for Determining Weighting Functions ....... 206
7.1.4 Electrical and Physical Length of a Coupler ......... 209
7.1.5 Design Procedure .................................... 210
7.2 Asymmetrical Couplers ..................................... 214
References ................................................ 217
CHAPTER 8
Tight Couplers ................................................ 219
8.1 Introduction .............................................. 219
8.2 Branch-Line Couplers ...................................... 220
8.2.1 Modified Branch-Line Coupler ........................ 223
8.2.2 Reduced-Size Branch-Line Coupler .................... 225
8.2.3 Lumped-Element Branch-Line Coupler .................. 230
8.2.4 Broadband Branch-Line Coupler ....................... 233
8.3 Rat-Race Coupler .......................................... 233
8.3.1 Modified Rat-Race Coupler ........................... 237
8.3.2 Reduced-Size Rat-Race Coupler ....................... 239
8.3.3 Lumped-Element Rat-Race Coupler ..................... 240
8.4 Multiconductor Directional Couplers ....................... 242
8.4.1 Theory of Interdigital Couplers ..................... 243
8.4.2 Design of Interdigital Couplers ..................... 245
8.5 Tandem Couplers ........................................... 252
8.6 Multilayer Tight Couplers ................................. 255
8.6.1 Broadside Couplers .................................. 255
8.6.2 Re-Entrant Mode Couplers ............................ 258
8.7 Compact Couplers .......................................... 261
8.7.1 Lumped-Element Couplers ............................. 262
8.7.2 Spiral Directional Couplers ......................... 262
8.7.3 Meander Line Directional Coupler .................... 263
8.8 Other Tight Couplers ...................................... 264
References ................................................ 265
CHAPTER 9
Coupled-Line Filter Fundamentals .............................. 269
9.1 Introduction .............................................. 269
9.1.1 Types of Filters .................................... 270
9.1.2 Applications ........................................ 270
9.2 Theory and Design of Filters .............................. 271
9.2.1 Maximally Flat or Butterworth Prototype ............. 272
9.2.2 Chebyshev Response .................................. 272
9.2.3 Other Response-Type Filters ......................... 275
9.2.4 LC Filter Transformation ............................ 275
9.2.5 Filter Analysis and CAD Methods ..................... 279
9.2.6 Some Practical Considerations ....................... 280
9.3 Parallel-Coupled Line Filters ............................. 283
9.3.1 Design Example ...................................... 285
9.4 Interdigital Filters ...................................... 287
9.4.1 Design Examples ..................................... 287
9.5 Combline Filters .......................................... 290
9.5.1 Design Example ...................................... 291
9.6 The Hairpin-Line Filter ................................... 295
9.6.1 Design Example ...................................... 297
9.7 Parallel-Coupled Bandstop Filter .......................... 300
9.7.1 Design Example ...................................... 301
References ................................................ 304
CHAPTER 10
Advanced Coupled-Line Filters ................................. 307
10.1 Introduction ............................................. 307
10.2 Coupled-Line Filters with Enhanced Stopband
Performance .............................................. 307
10.2.1 Design Using Unevenly-Coupled Stages .............. 307
10.2.2 Design Using Periodically Nonuniform Coupled
Lines ............................................. 314
10.2.3 Design Using Meandered Parallel-Coupled Lines ..... 320
10.2.4 Design Using Defected Ground Structures ........... 324
10.3 Coupled-Line Filters Exhibiting Advanced Filtering
Characteristics .......................................... 327
10.3.1 Filters with Cross-Coupled Resonators ............. 327
10.3.2 Filters with Source-Load Coupling ................. 335
10.3.3 Filters with Asymmetric Port Excitations .......... 347
10.4 Interdigital Filters Using Stepped Impedance
Resonators ............................................... 352
10.4.1 Narrowband Design ................................. 354
10.4.2 Wideband Design ................................... 356
10.5 Dual-Band Filters ........................................ 359
References ............................................... 367
CHAPTER 11
Filters Using Advanced Materials and Technologies ............. 371
11.1 Introduction ............................................. 371
11.2 Superconductor Coupled-Line Filters ...................... 371
11.2.1 Cascaded Quadruplet and Triplet Filters ........... 371
11.2.2 High-Order Selective Filters with Group-Delay
Equalization ...................................... 377
11.3 Micromachined Filters .................................... 385
11.3.1 Miniature Interdigital Filters on Silicon ......... 387
11.3.2 Overlay Coupled CPW Filters ....................... 390
11.4 Filters Using Advanced Dielectric Materials .............. 391
11.4.1 Low-Temperature Cofired Ceramic Filters ........... 392
11.4.2 Liquid Crystal Polymer Filters .................... 396
11.5 Filters for Ultra-Wideband (UWB) Technology .............. 400
11.5.1 Optimum Stub Line Filters ......................... 401
11.5.2 Multimode Coupled-Line Filters .................... 406
11.5.3 Microstrip-Coplanar Waveguide Coupled-Line
Filters ........................................... 410
11.5.4 UWB Filters with Notch Band ....................... 421
11.6 Metamaterial Filters ..................................... 428
References ............................................... 438
CHAPTER 12
Coupled-Line Circuit Components ............................... 443
12.1 DC Blocks ................................................ 443
12.1.1 Analysis .......................................... 443
12.1.2 Broadband DC Block ................................ 446
12.1.3 Biasing Circuits .................................. 446
12.1.4 Millimeter-Wave DC Block .......................... 449
12.1.5 High-Voltage DC Block ............................. 451
12.2 Coupled-Line Transformers ................................ 452
12.2.1 Open-Circuit Coupled-Line Transformers ............ 452
12.2.2 Transmission Line Transformers .................... 456
12.3 Interdigital Capacitor ................................... 461
12.3.1 Approximate Analysis .............................. 462
12.3.2 Full-Wave Analysis ................................ 464
12.4 Spiral Inductors ......................................... 465
12.5 Spiral Transformers ...................................... 472
12.6 Other Coupled-Line Components ............................ 475
References ............................................... 476
CHAPTER 13
Baluns ........................................................ 481
13.1 Introduction ............................................. 481
13.2 Microstrip-to-Balanced Stripline Balun ................... 482
13.3 Analysis of a Coupled-Line Balun ......................... 486
13.4 Planar Transmission Line Baluns .......................... 490
13.4.1 Analysis .......................................... 493
13.4.2 Examples .......................................... 496
13.5 Marchand Balun ........................................... 498
13.5.1 Coaxial Marchand Balun ............................ 501
13.5.2 Synthesis of Marchand Balun ....................... 505
13.5.3 Examples of Marchand Baiuns ....................... 509
13.6 Other Baluns ............................................. 518
13.6.1 Coplanar Waveguide Baluns ......................... 518
13.6.2 Triformer Balun ................................... 518
13.6.3 Planar-Transformer Balun .......................... 519
References ........................................ 524
About the Authors ............................................. 529
Index ......................................................... 531
|
