Introduction to RF Design Using EM Simulators (Artech House Microwave Library)

Introduction to RF Design Using EM Simulators......Page 2
Contents......Page 6
Preface......Page 14
1.1.2 Model of a Light bulb and a Battery......Page 16
1.1.3 Electric Field in the Vicinity of the Wires......Page 18
1.1.4 Electric Field Due to AC Power......Page 19
1.3 Transmission Lines with Confined Fields......Page 20
1.3.1 Model of a Waveguide Tube......Page 21
1.3.2 Observation of Electric Fields, Magnetic Fields, and Currents......Page 22
1.4.1 Microstrip Is Great for Printed Circuit Boards......Page 24
1.4.2 Fundamentals of the Microstrip Line......Page 25
1.5.1 What Is Characteristic Impedance?......Page 27
1.5.3 TEM Mode......Page 28
1.6.1 Modeling a Microstrip Line......Page 30
1.6.2 Understanding Our MSL—Obtaining S-Parameters......Page 37
1.6.3 Characteristic Impedance of the MSL......Page 39
1.7 Summary......Page 41
2.1.1 Transmission Line Bend......Page 42
2.1.2 Looking at the Current Distribution......Page 43
2.1.3 Viewing Electric and Magnetic Fields......Page 44
2.2.1 Higher Frequencies Usually Mean More Radiation......Page 46
2.3.1 The Right-Angle Bend Has Problems......Page 48
2.3.2 Standing Waves Come from Reflection......Page 49
2.3.3 How Is a Standing Wave Generated?......Page 50
2.4 Meander Lines......Page 53
2.4.1 Electric Field Representation......Page 54
2.5.1 The Normal Mode and the Common Mode......Page 55
2.5.2 Location of the Loop and Common Mode Current......Page 56
2.5.4 Relation Between Common Mode Current and Radiation......Page 57
2.7 Where Does the Radiation Go?......Page 59
2.8.2 Maxwell’s Hypothesis......Page 62
2.8.3 Electromagnetic Waves and Maxwell......Page 63
2.9.2 A Transmission Line or an Antenna?......Page 64
2.10 Skin Depth......Page 65
2.11.1 Draw a Right-Angle Bend......Page 66
2.11.2 The Effect of Cutting Corners......Page 67
2.12 Summary......Page 70
3.1.1 Definition of S-Parameters......Page 72
3.2 Let’s Use the Network Analyzer......Page 74
3.2.1 The Importance of Calibration......Page 75
3.3 S-Parameters of Four Bent Coupled Lines......Page 76
3.3.1 How to Evaluate S-Parameters......Page 78
3.4.1 PCB Interconnect Example......Page 79
3.4.2 Searching for Problems by Viewing the Current Distribution......Page 80
3.5 Ground Bounce and Ground Loops......Page 81
3.5.1 Example of Ground Bounce and Its Analysis......Page 82
3.6.1 Characteristic Impedance of the Waveguide Tube......Page 85
3.6.3 A Useful Method Due to Heaviside......Page 87
3.6.4 Matching Source to Load......Page 89
3.6.5 Why Is 50Ω the Standard?......Page 90
3.6.6 Characteristic Impedance of a Microstrip Line......Page 92
3.7.1 Modeling the Discontinuity......Page 93
3.7.2 Simulation Result Including Port Connecting Transmission Lines......Page 94
3.7.3 Surface Current Distribution......Page 95
3.7.5 Display Subsections......Page 96
3.7.6 Simulation with Removal of Port Connecting Transmission Lines......Page 97
3.7.7 Comparing S-Parameter Results......Page 99
3.7.8 Coupled-Line Right-Angle MSL Bend......Page 100
3.7.9 MSL Crosstalk Reduction......Page 101
3.7.10 Simulation of Crosstalk for More Than Two Lines......Page 102
3.8 Summary......Page 105
4.1.1 Microstrip Lines Are Distributed Circuits......Page 108
4.2 Design of Microwave Circuits......Page 109
4.3 Bent Coupled Lines Again......Page 110
4.4 A High-Speed Digital Circuit......Page 112
4.4.1 Guidelines for Frequency Selection......Page 114
4.4.2 Generation of a SPICE File......Page 115
4.4.3 The RLGC Matrix......Page 118
4.5.2 Dividing a Circuit......Page 120
4.5.3 Creation of Geometry File......Page 121
4.5.4 Simulating the Divided Circuit......Page 122
4.5.5 Key Point on Where to Set Dividing Lines......Page 123
4.5.6 Evaluation of the Result of Simulation......Page 124
4.6 Simulation of a T-Type Attenuator......Page 126
4.6.2 Creation of a Netlist File......Page 127
4.7.1 What Is a Left-Handed System?......Page 129
4.7.2 Realization of Meta-Materials......Page 130
4.7.3 Fields in a Left-Handed System......Page 131
4.8.1 SPICE Subcircuit of a Right-Angle MSL Bend......Page 134
4.8.2 Create a SPICE Subcircuit as a Symbol......Page 137
4.8.3 Using Parts......Page 139
4.8.4 Register the Subcircuit LBEND2.lib in the Circuit Schematic......Page 141
4.9 Summary......Page 143
5.1.1 Necessity of Impedance Matching......Page 146
5.1.2 Simulation of MSLs......Page 147
5.2 Simple MSL Model......Page 148
5.2.1 Wavelength in Vacuum and Dielectrics......Page 151
5.3.1 Interpretation of S-Parameters......Page 152
5.3.3 Difference Due to Slit Direction......Page 154
5.3.4 Electromagnetic Field Around the Substrate......Page 155
5.3.5 What Happens at Frequencies of Low Reflection?......Page 157
5.4.1 A Physical Quantity to Represent the Effectiveness of a Shield......Page 159
5.4.2 Effectiveness of a Magnetic Shield......Page 160
5.4.4 A Standing Wave in Space......Page 161
5.4.5 Absorption of Electromagnetic Waves......Page 162
5.5.1 Drawing the MSL Ground Plane Including the Slit......Page 164
5.5.2 Add the Ground Plane and the MSL Ports......Page 166
5.5.3 Including the Effect of Radiation......Page 167
5.5.4 Simulate a Radiating MSL......Page 169
5.6 Summary......Page 173
6.1.1 What Is a Differential Transmission Line?......Page 176
6.2 Is the Differential Line a Wonder Drug?......Page 178
6.2.1 Interpreting the Loss Results......Page 179
6.2.2 Interpreting the Crosstalk Results......Page 180
6.2.3 Reducing Crosstalk with a Differential Pair......Page 181
6.3.1 Relation Between Normal Mode, Common Mode, and Radiation Noise......Page 184
6.3.2 Investigation of the Common Mode......Page 186
6.4.1 The Electric Field Observed at 3m from the Circuit......Page 188
6.4.2 Magnetic Field Around a Line......Page 190
6.4.3 Field Loops and Electromagnetic Interference (EMI)......Page 193
6.4.4 Far-Field Radiation......Page 194
6.5 Confirming This Chapter by Simulation......Page 195
6.5.2 A Stacked Differential Pair......Page 196
6.5.3 Evaluating Radiation......Page 198
6.5.4 Reducing Memory Requirements......Page 199
6.6 Summary......Page 202
7.1.1 What Is EMC?......Page 204
7.2 Electromagnetic Waves Penetrating Through an Aperture......Page 206
7.2.1 Exploring the Properties of the Frequency-Domain Response......Page 208
7.2.3 Magnetic Field Distribution Between Layers......Page 209
7.3 Housing Resonances......Page 210
7.3.1 Analyzing Resonant Cavity Modes......Page 213
7.4 A PCB Inside a Housing......Page 215
7.5 The Microprocessor Unit Heat Sink and Radiation Noise......Page 217
7.5.1 A Ventilation Slit Becomes an Antenna......Page 219
7.6 Troubleshooting Radiation Noise Problems......Page 221
7.6.2 Size of Air Vents......Page 222
7.6.3 Investigating Problems at the Module Level......Page 223
7.6.4 Slit Between the Module and the Cover......Page 226
7.6.5 EMI from the Power Cable......Page 227
7.6.6 The Effect of Gaskets......Page 228
7.6.7 Effects of Lossy Dielectric Material......Page 229
7.7 Radio Wave Absorber and Keeping Down the Radiation Noise......Page 231
7.7.1 Measurement of a Noise Suppression Sheet......Page 233
7.7.2 Measuring Transmission Attenuation Power Ratio......Page 235
7.7.3 Effects of Radio Wave Absorbers......Page 236
7.8 Waveguide Mode Tutorial......Page 238
7.9 Confirming This Chapter by Simulation......Page 239
7.9.1 Examining a Cavity Resonance......Page 240
7.9.2 Simulation of a Noise Suppression Sheet......Page 242
7.10 Summary......Page 248
8.1.1 A Transmission Line Named Space......Page 250
8.1.3 Prediction of Electromagnetic Waves......Page 251
8.2 The Hertzian Dipole, the Very First Antenna......Page 252
8.3 Patch Antenna for Global Positioning Service......Page 255
8.4 A Patch Antenna Fed by an MSL......Page 257
8.4.1 Patch Antenna with an Offset Feed......Page 260
8.5.1 The Influence of a Car Body......Page 261
8.6 Electromagnetic Susceptibility and ElectromagneticInterference......Page 264
8.6.1 Calculation of the EMS......Page 265
8.7 EMI and Antennas......Page 267
8.8.1 Modeling of a Patch......Page 268
8.8.2 Setting a Via Port......Page 269
8.8.3 Interpreting the Result......Page 270
8.8.4 Investigating the Surface Current Distribution......Page 272
8.9 Summary......Page 274
9.1.1 Capabilities of Electromagnetic Simulators......Page 276
9.2.1 Implementation of Shielded Method of Moments......Page 277
9.2.2 Other Method of Moments Implementations......Page 280
9.3 FDTD and Its Friends......Page 282
9.4 Frequency Domain Versus Time Domain......Page 283
9.5 Accuracy of Electromagnetic Simulators......Page 285
9.6 Utilization of Electromagnetic Simulators......Page 287
9.6.1 The Impact of Electromagnetic Simulation......Page 289
9.7 Summary......Page 290
Appendix:Sonnet Lite Installation......Page 292
About the Authors......Page 294
Index......Page 296