Preface xv
1 Introduction 1
1.1 Types and Classes of Remote Sensing Data 1
1.2 Brief History of Remote Sensing 6
1.3 Remote Sensing Space Platforms 13
1.4 Transmission Through the Earth and Planetary Atmospheres 15
References and Further Reading 18
2 Nature and Properties of Electromagnetic Waves 19
2.1 Fundamental Properties of Electromagnetic Waves 19
2.1.1 Electromagnetic Spectrum 19
2.1.2 Maxwell's Equations 20
2.1.3 Wave Equation and Solution 21
2.1.4 Quantum Properties of Electromagnetic Radiation 21
2.1.5 Polarization 22
2.1.6 Coherency 25
2.1.7 Group and Phase Velocity 26
2.1.8 Doppler Effect 27
2.2 Nomenclature and Definition of Radiation Quantities 30
2.2.1 Radiation Quantities 30
2.2.2 Spectral Quantities 31
2.2.3 Luminous Quantities 32
2.3 Generation of Electromagnetic Radiation 32
2.4 Detection of Electromagnetic Radiation 34
2.5 Interaction of Electromagnetic Waves with Matter: Quick Overview 35
2.6 Interaction Mechanisms Throughout the Electromagnetic Spectrum 38
Exercises 42
References and Further Reading 43
3 Solid Surfaces Sensing in the Visible and Near Infrared 44
3.1 Source Spectral Characteristics 44
3.2 Wave-Surface Interaction Mechanisms 47
3.2.1 Reflection, Transmission, and Scattering 48
3.2.2 Vibrational Processes 51
3.2.3 Electronic Processes 54
3.2.4 Fluorescence 59
3.3 Signature of Solid Surface Materials 61
3.3.1 Signature of Geologic Materials 61
3.3.2 Signature of Biologic Materials 62
3.3.3 Depth of Penetration 67
3.4 Passive Imaging Sensors 70
3.4.1 Imaging Basics 70
3.4.2 Sensor Elements 71
3.4.3 Detectors 76
3.5 Types of Imaging Systems 81
3.6 Description of Some Visible/Infrared Imaging Sensors 84
3.6.1 Landsat Enhanced Thematic Mapper Plus (ETM+) 84
3.6.2 Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) 87
3.6.3 Mars Orbiter Camera (MOC) 89
3.6.4 Mars Exploration Rover Panchromatic Camera (Pancam) 90
3.6.5 Cassini Imaging Instrument 91
3.6.6 Juno Imaging System 93
3.6.7 Europa Imaging System 93
3.6.8 Cassini Visual and Infrared Mapping Spectrometer (VIMS) 94
3.6.9 Chandrayaan Imaging Spectrometer M3 95
3.6.10 Sentinel Multispectral Imager 95
3.6.11 Airborne Visible-Infrared Imaging Spectrometer (AVIRIS) 95
3.7 Active Sensors 96
3.8 Surface Sensing at Very Short Wavelengths 97
3.8.1 Radiation Sources 98
3.8.2 Detection 98
3.9 Image Data Analysis 99
3.9.1 Detection and Delineation 100
3.9.2 Classification 107
3.9.3 Identification 110
Exercises 113
References and Further Reading 117
4 Solid-Surface Sensing: Thermal Infrared 121
4.1 Thermal Radiation Laws 121
4.1.1 Emissivity of Natural Terrain 123
4.1.2 Emissivity from the Sun and Planetary Surfaces 124
4.2 Heat Conduction Theory 126
4.3 Effect of Periodic Heating 128
4.4 Use of Thermal Emission in Surface Remote Sensing 131
4.4.1 Surface Heating by the Sun 131
4.4.2 Effect of Surface Cover 133
4.4.3 Separation of Surface Units Based on Their Thermal Signature 135
4.4.4 Example of Application in Geology 135
4.4.5 Effects of Clouds on Thermal Infrared Sensing 135
4.5 Use of Thermal Infrared Spectral Signature in Sensing 137
4.6 Thermal Infrared Sensors 141
4.6.1 Heat Capacity Mapping Radiometer 143
4.6.2 Thermal Infrared Multispectral Scanner 145
4.6.3 ASTER Thermal Infrared Imager 145
4.6.4 Spitzer Space Telescope 149
4.6.5 2001 Mars Odyssey Thermal Emission Imaging System (THEMIS) 150
4.6.6 Advanced Very High Resolution Radiometer (AVHRR) 151
Exercises 154
References and Further Reading 156
5 Solid-Surface Sensing: Microwave Emission 159
5.1 Power-Temperature Correspondence 160
5.2 Simple Microwave Radiometry Models 161
5.2.1 Effects of Polarization 163
5.2.2 Effects of the Observation Angle 163
5.2.3 Effects of the Atmosphere 164
5.2.4 Effects of Surface Roughness 164
5.3 Applications and Use in Surface Sensing 165
5.3.1 Application in Polar Ice Mapping 165
5.3.2 Application in Soil Moisture Mapping 166
5.3.3 Measurement Ambiguity 170
5.4 Description of Microwave Radiometers 170
5.4.1 Antenna and Scanning Configuration for Real-Aperture Radiometers 171
5.4.2 Synthetic Aperture Radiometers 172
5.4.3 Receiver Subsystems 177
5.4.4 Data Processing 179
5.5 Examples of Developed Radiometers 180
5.5.1 Scanning Multichannel Microwave Radiometer (SMMR) 180
5.5.2 Special Sensor Microwave Imager (SSM/I) 181
5.5.3 Tropical Rainfall Mapping Mission Microwave Imager (TMI) 183
5.5.4 AMSR-E 184
5.5.5 SMAP Radiometer 185
Exercises 185
References and Further Reading 187
6 Solid-Surface Sensing: Microwave and Radio Frequencies 190
6.1 Surface Interaction Mechanism 190
6.1.1 Surface Scattering Models 192
6.1.2 Absorption Losses and Volume Scattering 197
6.1.3 Effects of Polarization 200
6.1.4 Effects of the Frequency 202
6.1.5 Effects of the Incidence Angle 205
6.1.6 Scattering from Natural Terrain 206
6.2 Basic Principles of Radar Sensors 209
6.2.1 Antenna Beam Characteristics 209
6.2.2 Signal Properties: Spectrum 213
6.2.3 Signal Properties: Modulation 216
6.2.4 Range Measurements and Discrimination 218
6.2.5 Doppler (Velocity) Measurement and Discrimination 221
6.2.6 High-Frequency Signal Generation 222
6.3 Imaging Sensors: Real Aperture Radars 224
6.3.1 Imaging Geometry 224
6.3.2 Range Resolution 225
6.3.3 Azimuth Resolution 225
6.3.4 Radar Equation 226
6.3.5 Signal Fading 227
6.3.6 Fading Statistics 229
6.3.7 Geometric Distortion 232
6.4 Imaging Sensors: Synthetic Aperture Radars 234
6.4.1 Synthetic Array Approach 234
6.4.2 Focused vs. Unfocused SAR 235
6.4.3 Doppler Synthesis Approach 237
6.4.4 SAR Imaging Coordinate System 239
6.4.5 Ambiguities and Artifacts 240
6.4.6 Point Target Response 243
6.4.7 Correlation with Point Target Response 246
6.4.8 Advanced SAR Techniques 248
6.4.9 Description of SAR Sensors and Missions 265
6.4.10 Applications of Imaging Radars 278
6.5 Nonimaging Radar Sensors: Scatterometers 295
6.5.1 Examples of Scatterometer Instruments 295
6.5.2 Examples of Scatterometer Data 303
6.6 Nonimaging Radar Sensors: Altimeters 304
6.6.1 Examples of Altimeter Instruments 307
6.6.2 Altimeter Applications 310
6.6.3 Imaging Altimetry 312
6.6.4 Wide Swath Ocean Altimeter 314
6.7 Nonconventional Radar Sensors 317
6.8 Subsurface Sounding 317
Exercises 320
References and Further Reading 323
7 Ocean Surface Sensing 334
7.1 Physical Properties of the Ocean Surface 334
7.1.1 Tides and Currents 335
7.1.2 Surface Waves 336
7.2 Mapping of the Ocean Topography 339
7.2.1 Geoid Measurement 339
7.2.2 Surface Wave Effects 343
7.2.3 Surface Wind Effects 345
7.2.4 Dynamic Ocean Topography 345
7.2.5 Ancillary Measurements 349
7.3 Surface Wind Mapping 351
7.3.1 Observations Required 352
7.3.2 Nadir Observations 355
7.4 Ocean Surface Imaging 356
7.4.1 Radar Imaging Mechanisms 356
7.4.2 Examples of Ocean Features on Radar Images 359
7.4.3 Imaging of Sea Ice 361
7.4.4 Ocean Color Mapping 363
7.4.5 Ocean Surface Temperature Mapping 365
7.4.6 Ocean Salinity Mapping 370
Exercises 371
References and Further Reading 372
8 Basic Principles of Atmospheric Sensing and Radiative Transfer 377
8.1 Physical Properties of the Atmosphere 377
8.2 Atmospheric Composition 380
8.3 Particulates and Clouds 381
8.4 Wave Interaction Mechanisms in Planetary Atmospheres 383
8.4.1 Resonant Interactions 383
8.4.2 Spectral Line Shape 387
8.4.3 Nonresonant Absorption 389
8.4.4 Nonresonant Emission 391
8.4.5 Wave Particle Interaction, Scattering 391
8.4.6 Wave Refraction 392
8.5 Optical Thickness 392
8.6 Radiative Transfer Equation 393
8.7 Case of a Nonscattering Plane Parallel Atmosphere 395
8.8 Basic Concepts of Atmospheric Remote Sounding 396
8.8.1 Basic Concept of Temperature Sounding 397
8.8.2 Basic Concept for Composition Sounding 399
8.8.3 Basic Concept for Pressure Sounding 399
8.8.4 Basic Concept of Density Measurement 399
8.8.5 Basic Concept of Wind Measurement 399
Exercises 400
References and Further Reading 401
9 Atmospheric Remote Sensing in the Microwave Region 403
9.1 Microwave Interactions with Atmospheric Gases 403
9.2 Basic Concept of Downlooking Sensors 404
9.2.1 Temperature Sounding 406
9.2.2 Constituent Density Profile: Case of Water Vapor 408
9.3 Basic Concept for Uplooking Sensors 411
9.4 Basic Concept for Limblooking Sensors 412
9.5 Inversion Concepts 415
9.6 Basic Elements of Passive Microwave Sensors 418
9.7 Surface Pressure Sensing 420
9.8 Atmospheric Sounding by Occultation 420
9.9 Microwave Scattering by Atmospheric Particles 424
9.10 Radar Sounding of Rain 424
9.11 Radar Equation for Precipitation Measurement 427
9.12 The Tropical Rainfall Measuring Mission (TRMM) 428
9.13 Rain Cube 429
9.14 CloudSat 429
9.15 Cassini Microwave Radiometer 433
9.16 Juno Microwave Radiometer (MWR) 433
Exercises 433
References and Further Reading 434
10 Millimeter and Submillimeter Sensing of Atmospheres 440
10.1 Interaction with Atmospheric Constituents 440
10.2 Downlooking Sounding 442
10.3 Limb Sounding 444
10.4 Elements of a Millimeter Sounder 447
10.5 Submillimeter Atmospheric Sounder 453
Exercises 455
References and Further Reading 456
11 Atmospheric Remote Sensing in the Visible and Infrared 458
11.1 Interaction of Visible and Infrared Radiation with the Atmosphere 458
11.1.1 Visible and Near-Infrared Radiation 458
11.1.2 Thermal Infrared Radiation 461
11.1.3 Resonant Interactions 463
11.1.4 Effects of Scattering by Particulates 463
11.2 Downlooking Sounding 466
11.2.1 General Formulation for Emitted Radiation 466
11.2.2 Temperature Profile Sounding 467
11.2.3 Simple Case Weighting Functions 469
11.2.4 Weighting Functions for Off-Nadir Observations 470
11.2.5 Composition Profile Sounding 471
11.3 Limb Sounding 472
11.3.1 Limb Sounding by Emission 472
11.3.2 Limb Sounding by Absorption 474
11.3.3 Illustrative Example: Pressure Modulator Radiometer 474
11.3.4 Illustrative Example: Fourier Transform Spectroscopy 476
11.4 Sounding of Atmospheric Motion 479
11.4.1 Passive Techniques 479
11.4.2 Passive Imaging of Velocity Field: Helioseismology 482
11.4.3 Multi-Angle Imaging SpectroRadiometer (MISR) 484
11.4.4 Multi-Angle Imager for Aerosols (MAIA) 488
11.4.5 Active Techniques 489
11.5 Laser Measurement of Wind 489
11.6 Atmospheric Sensing at Very Short Wavelengths 490
Exercises 491
References and Further Reading 492
12 Ionospheric Sensing 497
12.1 Properties of Planetary Ionospheres 497
12.2 Wave Propagation in Ionized Media 498
12.3 Ionospheric Profile Sensing by Topside Sounding 501
12.4 Ionospheric Profile by Radio Occultation 503
Exercises 505
References and Further Reading 506
Appendix A: Use of Multiple Sensors for Surface Observations 507
Appendix B: Summary of Orbital Mechanics Relevant to Remote Sensing 511
Appendix C: Simplified Weighting Functions 521
Appendix D: Compression of a Linear FM Chirp Signal 524
Index 528
