سیستم‌های رادیومتر مایکروویو: طراحی و تحلیل، ویرایش دوم

Microwave radiometers are tools used for passive microwave remote sensing - a technological process that allows for the measurement of important parameters that help professionals understand and predict climate and weather patterns. Written by leading experts in industry and academia, this authoritative resource offers practitioners a solid understanding of radiometer systems and explains how to design a system based on given specifications, taking into account both technical aspects and geophysical realities. This second edition has been thoroughly updated to reflect the numerous advances that have been made in the field since the original edition was published in 1989. New material covered includes two of today's hottest microwave radiometry topics - polarimetric measurements and aperture synthesis. Microwave Radiometer Systems Design and Analysis Second Edition......Page 2 Contents......Page 6 Preface xi......Page 12 1 Introduction 1......Page 13 2 Summary 3......Page 15 3.2 The Sensitivity of the Radiometer 7......Page 19 3.3 Absolute Accuracy and Stability 9......Page 21 4.1 The Total Power Radiometer (TPR) 13......Page 24 4.2 The Dicke Radiometer (DR) 14......Page 25 4.3 The Noise-Injection Radiometer (NIR) 16......Page 27 4.4 The Correlation Radiometer (CORRAD) 18......Page 29 4.5 Hybrid Radiometer 20......Page 31 4.6 Other Radiometer Types 21......Page 32 5.1.1 Direct or Superheterodyne 25......Page 35 5.1.2 DSB or SSB with or without RF Preamplifier 26......Page 36 5.2.1 Microwave Part 27......Page 37 5.2.2 The Noise Figure and the Sensitivity of the Radiometer 29......Page 39 5.2.3 The IF Circuitry and the Detector 30......Page 40 5.2.4 The Extreme Signal Levels 32......Page 42 5.2.5 The LF Circuitry 33......Page 43 5.2.6 The Analog-to-Digital Converter 34......Page 44 5.2.7 On the Sampling in the Radiometer: Aliasing 37......Page 47 5.3 The Noise-Injection Radiometer 38......Page 48 5.4.1 DSB Receiver without RF Preamplifier 40......Page 50 5.4.2 SSB Receiver with RF Preamplifier 42......Page 52 5.5 Stability Considerations 43......Page 53 6 The DTU Noise-Injection Radiometers Example 47......Page 56 7.1 Polarimetry and Stokes Parameters 55......Page 63 7.3.1 Polarization Combining Radiometers 57......Page 65 7.3.2 Correlation Radiometers 60......Page 68 7.4 Sensitivities 62......Page 70 7.6 The DTU Polarimetric System 64......Page 72 8.1 Introduction 69......Page 77 8.2.1 RF Processing 72......Page 80 8.2.2 Basic Equation 73......Page 81 8.2.3 Image Processing 74......Page 82 8.2.4 Sensitivity 75......Page 83 8.3 Example 76......Page 84 9.1 Why Calibrate? 81......Page 88 9.2 Calibration Sources 82......Page 89 9.3 Example: Calibration of a 5-GHz Radiometer 86......Page 93 9.4 Linearity Measured by Simple Means 87......Page 94 9.4.1 Background 88......Page 95 9.4.2 Simple Three-Point Calibration 89......Page 96 9.4.3 Linearity Checked by Slope Measurements 92......Page 99 9.4.4 Measurements 93......Page 100 9.5 Calibration of Polarimetric Radiometers 96......Page 103 10.1 Background 99......Page 106 10.2 The Radiometers Used in the Experiments 100......Page 107 10.3 The Experimental Setup 101......Page 108 10.4 5-GHz Sensitivity Measurements 102......Page 109 10.5.1 Discussion of the 5-GHz DR Results 103......Page 110 10.5.2 The 5-GHz DR with Correction Algorithm 105......Page 112 10.5.3 The 17-GHz NIR Results 109......Page 116 10.5.4 Discussion of the TPR Results 111......Page 118 10.5.5 Back-End Stability 113......Page 120 10.6 Conclusions 114......Page 121 11.1 Beam Efficiency and Losses 117......Page 123 11.2 Antenna Types 119......Page 125 11.3 Imaging Considerations 121......Page 127 11.4 The Dwell Time Per Footprint Versus the Sampling Time in the Radiometer 125......Page 131 11.5 Receiver Considerations for Imagers 130......Page 136 12 Relationships Between Swath Width, Footprint, Integration Time, Sensitivity, Frequency, and Other Parameters for Satellite-Borne, Real Aperture Imaging Systems 133......Page 138 12.1 Mechanical Scan 134......Page 139 12.2 Push-Broom Systems 139......Page 144 12.3 Summary and Discussion 140......Page 145 12.4.2 Coastal Salinity Sensor 143......Page 148 12.4.3 Realistic Salinity Sensor 144......Page 149 13.1 Background 147......Page 151 13.2.1 General Geometric and Radiometric Characteristics 149......Page 153 13.2.2 Instrument Options 152......Page 156 13.2.4 Instrument Layout and Receiver Type 156......Page 160 13.3.1 The Direct Receivers (10.65–36.5 GHz) 157......Page 161 13.3.2 The 89-GHz DSB Receivers 158......Page 162 13.3.3 Integrated Receivers: Weight and Power 159......Page 163 13.3.4 Performance of the Receivers 160......Page 164 13.3.5 Critical Design Features 161......Page 165 13.4 Antenna Design 163......Page 167 13.5.1 Prelaunch Radiometric Calibration 165......Page 169 13.5.2 On-Board Calibration 166......Page 170 13.6.1 System Weight and Power 167......Page 171 13.6.2 Data Rate 168......Page 172 13.7 Summary 169......Page 173 14.1 Background 171......Page 175 14.2 The Brightness Temperature of the Sea 172......Page 176 14.3 The Brightness Temperature of Moist Soil 175......Page 179 14.5.1 Sensitivity Considerations 177......Page 181 14.5.2 The 1.4-GHz Noise-Injection Radiometer Receiver 178......Page 182 14.5.4 Layout of the System 181......Page 185 14.6 Calibration 184......Page 188 14.7.1 The Faraday Rotation 186......Page 190 14.7.2 Correction Based on Knowing the Rotation Angle 187......Page 191 14.7.3 Correction Based on the Polarization Ratio 189......Page 193 14.7.5 Circumventing the Problem by Using the First Stokes Parameter 191......Page 195 14.8.1 Space Radiation 192......Page 196 14.9 Summary 193......Page 197 15.1 Introduction 197......Page 201 15.2 Implementation of Synthesis 198......Page 202 15.3.1 Hardware 200......Page 204 15.3.2 Image Reconstruction 204......Page 208 15.3.3 Calibration 205......Page 209 15.3.4 Discussion 207......Page 211 15.3.5 Example of Imagery 208......Page 212 15.4.1 HYDROSTAR 211......Page 215 15.4.2 SMOS 214......Page 218 Acronyms 219......Page 223 Annotation Microwave radiometers are tools used for passive microwave remote sensing--"a technological process that allows for the measurement of important parameters that help professionals understand and predict climate and weather patterns. Written by leading experts in industry and academia, this authoritative resource offers practitioners a solid understanding of radiometer systems and explains how to design a system based on given specifications, taking into account both technical aspects and geophysical realities. This second edition has been thoroughly updated to reflect the numerous advances that have been made in the field since the original edition was published in 1989. New material covered includes two of today's hottest microwave radiometry topics--"polarimetric measurements and aperture synthesis Thoroughly revising and updating an Artech House classic from 1989, this authoritative resource offers you a comprehensive and current understanding of radiometer systems and shows you how to design a system based on given specifications, taking into account both technical aspects and geophysical realities. The second edition contains a wealth of new material, including coverage of two of today's hottest microwave radiometry topics - polarimetric measurements and aperture synthesis. The book provides you with a complete explanation of radiometer sensitivity, and describes the concept of absolu

Thoroughly revising and updating an Artech House classic from 1989, this authoritative resource offers you a comprehensive and current understanding of radiometer systems and shows you how to design a system based on given specifications, taking into acco