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gsmman2006
2011-11-12, 03:41 AM
Introduction 1
1.1 Frequency Designations 1
1.2 Modes of Propagation 3
1.2.1 Line-of-Sight Propagation and the Radio Horizon 3
1.2.2 Non-LOS Propagation 5
1.2.2.1 Indirect or Obstructed Propagation 6
1.2.2.2 Tropospheric Propagation 6
1.2.2.3 Ionospheric Propagation 6
1.2.3 Propagation Effects as a Function of Frequency 9
1.3 Why Model Propagation? 10
1.4 Model Selection and Application 11
1.4.1 Model Sources 11
1.5 Summary 12
References 12
Exercises 13
2. Electromagnetics and RF Propagation 14
2.1 Introduction 14
2.2 The Electric Field 14
2.2.1 Permittivity 15
2.2.2 Conductivity 17
2.3 The Magnetic Field 18
2.4 Electromagnetic Waves 20
2.4.1 Electromagnetic Waves in a Perfect Dielectric 22
2.4.2 Electromagnetic Waves in a Lossy Dielectric or
Conductor 22
2.4.3 Electromagnetic Waves in a Conductor 22
2.5 Wave Polarization 24
2.6 Propagation of Electromagnetic Waves at Material
Boundaries 25
2.6.1 Dielectric to Dielectric Boundary 26
vii
2.6.2 Dielectric-to-Perfect Conductor Boundaries 31
2.6.3 Dielectric-to-Lossy Dielectric Boundary 31
2.7 Propagation Impairment 32
2.8 Ground Effects on Circular Polarization 33
2.9 Summary 35
References 36
Exercises 36
3. Antenna Fundamentals 38
3.1 Introduction 38
3.2 Antenna Parameters 38
3.2.1 Gain 39
3.2.2 Effective Area 39
3.2.3 Radiation Pattern 42
3.2.4 Polarization 44
3.2.5 Impedance and VSWR 44
3.3 Antenna Radiation Regions 45
3.4 Some Common Antennas 48
3.4.1 The Dipole 48
3.4.2 Beam Antennas 50
3.4.3 Horn Antennas 52
3.4.4 Reflector Antennas 52
3.4.5 Phased Arrays 54
3.4.6 Other Antennas 54
3.5 Antenna Polarization 55
3.5.1 Cross-Polarization Discrimination 57
3.5.2 Polarization Loss Factor 58
3.6 Antenna Pointing loss 62
3.7 Summary 63
References 64
Exercises 65
4. Communication Systems and the Link Budget 66
4.1 Introduction 66
4.2 Path Loss 67
4.3 Noise 69
4.4 Interference 76
4.5 Detailed Link Budget 79
4.5.1 EIRP 80
4.5.2 Path Loss 80
4.5.3 Receiver Gain 82
4.5.4 Link Margin 83
4.5.5 Signal-to-Noise Ratio 83
viii CONTENTS
4.6 Summary 84
References 85
Exercises 85
5. Radar Systems 87
5.1 Introduction 87
5.2 The Radar Range Equation 88
5.3 Radar Measurements 93
5.3.1 Range Measurement 93
5.3.2 Doppler Measurement 95
5.3.3 Angle Measurement 95
5.3.4 Signature Measurement 98
5.4 Clutter 99
5.4.1 Area Clutter 99
5.4.2 Volume Clutter 105
5.4.3 Clutter Statistics 106
5.5 Atmospheric Impairments 106
5.6 Summary 107
References 108
Exercises 109
6. Atmospheric Effects 111
6.1 Introduction 111
6.2 Atmospheric Refraction 112
6.2.1 The Radio Horizon 112
6.2.2 Equivalent Earth Radius 113
6.2.3 Ducting 116
6.2.4 Atmospheric Multipath 117
6.3 Atmospheric Attenuation 121
6.4 Loss From Moisture and Precipitation 125
6.4.1 Fog and Clouds 126
6.4.2 Snow and Dust 130
6.5 Summary 131
References 132
Exercises 132
7. Near-Earth Propagation Models 134
7.1 Introduction 134
7.2 Foliage Models 134
7.2.1 Weissberger’s Model 135
7.2.2 Early ITU Vegetation Model 135
7.2.3 Updated ITU Vegetation Model 137
CONTENTS ix
7.2.3.1 Terrestrial Path with One Terminal
in Woodland 138
7.2.3.2 Single Vegetative Obstruction 138
7.3 Terrain Modeling 141
7.3.1 Egli Model 141
7.3.2 Longley–Rice Model 143
7.3.3 ITU Model 144
7.4 Propagation in Built-Up Areas 146
7.4.1 Young Model 146
7.4.2 Okumura Model 146
7.4.3 Hata Model 151
7.4.4 COST 231 Model 152
7.4.5 Lee Model 153
7.4.6 Comparison of Propagation Models for
Built-Up Areas 157
7.5 Summary 159
References 160
Exercises 161
8. Fading and Multipath Characterization 163
8.1 Introduction 163
8.2 Ground-Bounce Multipath 164
8.2.1 Surface Roughness 174
8.2.2 Fresnel Zones 175
8.2.3 Diffraction and Huygen’s Principle 179
8.2.4 Quantifying Diffraction Loss 179
8.3 Large-Scale or Log-Normal Fading 186
8.4 Small-Scale Fading 193
8.4.1 Delay Spread 194
8.4.2 Doppler Spread 198
8.4.3 Channel Modeling 199
8.4.4 The Probabilistic Nature of Small-Scale Fading 200
8.5 Summary 203
References 205
Exercises 206
9. Indoor Propagation Modeling 208
9.1 Introduction 208
9.2 Interference 208
9.3 The Indoor Environment 209
9.3.1 Indoor Propagation Effects 209
9.3.2 Indoor Propagation Modeling 210
x CONTENTS
9.3.3 The ITU Indoor Path Loss Model 210
9.3.4 The Log-Distance Path Loss Model 214
9.4 Summary 216
References 216
Exercises 216
10. Rain Attenuation of Microwave and Millimeter Wave Signals 218
10.1 Introduction 218
10.2 Link Budget 219
10.3 Rain Fades 222
10.3.1 Specific Attenuation Due to Rainfall 222
10.3.2 The ITU Model 224
10.3.3 The Crane Global Model 229
10.3.4 Other Rain Models 234
10.3.5 Rain Attenuation Model Comparison 234
10.3.6 Slant Paths 234
10.4 The Link Distance Chart 234
10.5 Availability Curves 237
10.6 Other Precipitation 237
10.7 Cross-Polarization Effects 239
10.8 Summary 239
References 240
Exercises 241
Appendix 10A: Data for Rain Attenuation Models 242
11. Satellite Communications 246
11.1 Introduction 246
11.2 Satellite Orbits 247
11.3 Satellite Operating Frequency 249
11.4 Satellite Path Free-Space Loss 249
11.5 Atmospheric Attenuation 252
11.6 Ionospheric Effects 255
11.7 Rain Fades 255
11.7.1 ITU Rain Attenuation Model for Satellite Paths 257
11.7.2 Crane Rain Attenuation Model for Satellite Paths 264
11.7.3 The DAH Rain Attenuation Model 270
11.8 Antenna Considerations 273
11.9 Noise Temperature 274
11.9.1 The Hot-Pad Formula 276
11.9.2 Noise Due to Rain 278
11.9.3 Sun Outages 279
11.10 Summary 279
CONTENTS xi
References 280
Exercises 281
12. RF Safety 283
12.1 Introduction 283
12.2 Biological Effects of RF Exposure 285
12.3 CC Guidelines 287
12.4 Antenna Considerations 290
12.5 FCC Computations 292
12.5.1 Main Beam and Omnidirectional Antenna Analysis 292
12.5.2 Antenna Directivity 293
12.6 Station Evaluations 297
12.7 Summary 298
References 298
Exercises

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plz add thanks and REP

da_manole
2011-11-12, 04:22 AM
http://www.asrr.org/attachments/195_Introduction%20to%20RF%20Propagation%20-%20John%20S.%20Seybold-2005.pdf