Introduction to the Physics and Techniques of Remote Sensing

INTRODUCTION TO THE PHYSICS AND TECHNIQUES OF REMOTE SENSING

DISCOVER CUTTING EDGE THEORY AND APPLICATIONS OF MODERN REMOTE SENSING IN GEOLOGY, OCEANOGRAPHY, ATMOSPHERIC SCIENCE, IONOSPHERIC STUDIES, AND MORE

The thoroughly revised third edition of the Introduction to the Physics and Techniques of Remote Sensing delivers a comprehensive update to the authoritative textbook, offering readers new sections on radar interferometry, radar stereo, and planetary radar. It explores new techniques in imaging spectroscopy and large optics used in Earth orbiting, planetary, and astrophysics missions. It also describes remote sensing instruments on, as well as data acquired with, the most recent Earth and space missions.

Readers will benefit from the brand new and up-to-date concept examples and full-color photography, 50% of which is new to the series. You’ll learn about the basic physics of wave/matter interactions, techniques of remote sensing across the electromagnetic spectrum (from ultraviolet to microwave), and the concepts behind the remote sensing techniques used today and those planned for the future.

The book also discusses the applications of remote sensing for a wide variety of earth and planetary atmosphere and surface sciences, like geology, oceanography, resource observation, atmospheric sciences, and ionospheric studies. This new edition also incorporates:

A fulsome introduction to the nature and properties of electromagnetic waves An exploration of sensing solid surfaces in the visible and near infrared spectrums, as well as thermal infrared, microwave, and radio frequencies A treatment of ocean surface sensing, including ocean surface imaging and the mapping of ocean topography A discussion of the basic principles of atmospheric sensing and radiative transfer, including the radiative transfer equation

Perfect for senior undergraduate and graduate students in the field of remote sensing instrument development, data analysis, and data utilization, Introduction to the Physics and Techniques of Remote Sensing will also earn a place in the libraries of students, faculty, researchers, engineers, and practitioners in fields like aerospace, electrical engineering, and astronomy.

CHARLES ELACHI, PHD, is a Professor of electrical engineering and planetary science at Caltech. He was the Director of NASA’s Jet Propulsion Laboratory from 2001 to 2016. He played the leading role in the development of five Earth Orbiting Shuttle Imaging Radar missions and the Cassini Titan Radar mapping instrument. He taught the Physics of Remote Sensing at Caltech from 1982 to 2002.

JAKOB VAN ZYL, PHD, occupied numerous leadership positions at the Jet Propulsion Laboratory including the Radar Section, Planetary Exploration Program, Astronomy and Physics Program and as the Associate Director for advanced missions. He taught the Physics of Remote Sensing at Caltech from 2002 to 2020.

CHAPTER 1 INTRODUCTION 1

1-1 Types and Classes of Remote Sensing Data 2

1-2 Brief History of Remote Sensing 5

1-3 Remote Sensing Space Platforms 15

1-4 Transmission Through the Earth and Planetary Atmospheres 18

References and Further Reading 20

CHAPTER 2 NATURE AND PROPERTIES OF ELECTROMAGNETIC WAVES 22

2-1 Fundamental Properties of Electromagnetic Waves 22

2-1-1 Electromagnetic Spectrum 22

2-1-2 Maxwell’s Equations 23

2-1-3 Wave Equation and Solution 24

2-1-4 Quantum Properties of Electromagnetic Radiation 24

2-1-5 Polarization 25

2-1-6 Coherency 26

2-1-7 Group and Phase Velocity 27

2-1-8 Doppler Effect 29

2-2 Nomenclature and Definition of Radiation Quantities 32

2-2-1 Radiation Quantities 32

2-2-2 Spectral Quantities 33

2-2-3 Luminous Quantities 34

2-3 Generation of Electromagnetic Radiation 34

2-4 Detection of Electromagnetic Radiation 37

2-5 Interaction of Electromagnetic Waves with Matter: Quick Overview 37

2-6 Interaction Mechanisms Throughout the Electromagnetic Spectrum

Exercises 41

References and Further Reading 45

CHAPTER 3 SOLID SURFACES SENSING IN THE VISIBLE AND NEAR INFRARED 46

3-1 Source Spectral Characteristics 46

3-2 Wave-Surface Interaction Mechanisms 49

3-2-1 Reflection, Transmission, and Scattering 49

3-2-2 Vibrational Processes 54

3-2-3 Electronic Processes 57

3-2-4 Fluorescence 63

3-3 Signature of Solid Surface Materials 64

3-3-1 Signature of Geologic Materials 64

3-3-2 Signature of Biologic Materials 65

3-3-3 Depth of Penetration 67

3-4 Passive Imaging Sensors 71

3-4-1 Imaging Basics 74

3-4-2 Sensor Elements 75

3-4-3 Detectors 76

3-5 Types of Imaging Systems 83

3-6 Description of Some Visible/Infrared Imaging Sensors 87

3-6-1 Landsat-Enhanced Thematic Mapper Plus (ETM+) 88

3-6-2 Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER)

3-6-3 Mars Orbitor Camera (MOC)

3-6-4 Mars Exploration Rover Panchromatic Camera (Pancam) 90

3-6-5 Cassini Imaging Instrument

3-6-6 Juno Imaging System

3-6-7 Europa Imaging System

3-6-8 Cassini Visual and Infrared Mapping Spectrometer (VIMS)

3-6-9 Chandryon Imaging Spectrometer M3

3-6-10 Sentinel Multispectral Imager

3-6-11 Airborne Visible-Infrared Imaging Spectrometer

3-7 Active Sensors 93

3-8 Surface Sensing at Very Short Wavelengths 103

3-8-1 Radiation Sources 104

3-8-2 Detection 105

3-9 Image Data Analysis

3-9-1 Detection and Delineation

3-9-2 Classification

3-9-3 Identification

Exercises

References and Further Reading 110

CHAPTER 4 SOLID-SURFACE SENSING: THERMAL INFRARED 114

4-1 Thermal Radiation Laws 114

4-1-1 Emissivity of Natural Terrain 115

4-1-2 Emissivity from the Sun and Planetary Surfaces 118

4-2 Heat Conduction Theory 119

4-3 Effect of Periodic Heating 122

4-4 Use of Thermal Emission in Surface Remote Sensing 125

4-4-1 Surface Heating by the Sun 125

4-4-2 Effect of Surface Cover 127

4-4-3 Separation of Surface Units Based on Their Thermal Signature 129

4-4-4 Example of Application in Geology

4-4-5 Effects of Clouds on Thermal Infrared Sensing 129

4-5 Use of Thermal Infrared Spectral Signature in Sensing 133

4-6 Thermal Infrared Sensors 137

4-6-1 Heat Capacity Mapping Radiometer 137

4-6-2 Thermal Infrared Multispectral Scanner

4-6-3 ASTER Thermal Infrared Sensor

4-6-4 Spitzer Space Telescope

4-6-5 2001 Mars Odyssey Thermal Emission Imaging System (THEMIS)

4-6-6 Advanced Very High Resolution Radiometer (AVHRR)

Exercises 139

References and Further Reading 141

CHAPTER 5 SOLID-SURFACE SENSING: MICROWAVE EMISSION 142

5-1 Power-Temperature Correspondence 143

5-2 Simple Microwave Radiometry Models 144

5-2-1 Effects of Polarization 145

5-2-2 Effects of Observation Angle 147

5-2-3 Effects of the Atmosphere 147

5-2-4 Effects of Surface Roughness 147

5-3 Applications and Use in Surface Sensing 148

5-3-1 Application in Polar Ice Mapping 149

5-3-2 Application in Soil Moisture Mapping 152

5-3-3 Measurement Ambiguity 152

5-4 Description of Microwave Radiometers 154

5-4-1 Antenna and Scanning Configuration for Real-Aperture Radiometers 155

5-4-2 Synthetic-Aperture Radiometers 156

5-4-3 Receiver Subsystem 157

5-4-4 Data Processing 157

5-5 Examples of Developed Radiometers

5-5-1 Scanning Multichannel Microwave Radiometer (SMMR)

5-5-2 Special Sensor Microwave Imager (SSM/I)

5-5-3 Tropical Rainfall Mapping Mission Microwave Imager (TMI)

5-5-4 Advanced Microwave Scanning Radiometer for EOS (AMSR-E)

5-5-5 SMAP Radiometer

Exercises

References and Further Reading 160

CHAPTER 6 SOLID-SURFACE SENSING: MICROWAVE AND RADIO FREQUENCIES 161

6-1 Surface Interaction Mechanisms 163

6-1-1 Surface Scattering Models 163

6-1-2 Absorption Losses and Volume Scattering 167

6-1-3 Effects of Polarization 168

6-1-4 Effects of the Frequency 169

6-1-5 Effects of the Incidence Angle 170

6-1-6 Scattering from Natural Terrain 171

6-2 Basic Principles of Radar Sensors 176

6-2-1 Antenna Beam Characteristics 177

6-2-2 Signal Properties: Spectrum 182

6-2-3 Signal Properties: Modulation 184

6-2-4 Range Measurement and Discrimination 186

6-2-5 Doppler (Velocity) Measurement and Discrimination 190

6-2-6 High-Frequency Signal Generation 191

6-3 Imaging Sensors: Real Aperture Radars 193

6-3-1 Imaging Geometry 193

6-3-2 Range Resolution 194

6-3-3 Azimuth Resolution 195

6-3-4 Radar Equation 195

6-3-5 Signal Fading 196

6-3-6 Fading Statistics 199

6-3-7 Geometric Distortion 203

6-4 Imaging Sensors: Synthetic Aperture Radars 203

6-4-1 Synthetic-Array Approach 203

6-4-2 Focused Versus Unfocused SAR 205

6-4-3 Doppler-Synthesis Approach 207

6-4-4 SAR Imaging Coordinate System 208

6-4-5 Ambiguities and Artifacts 209

6-4-6 Point Target Response 210

6-4-7 Correlation With Point Target Response

6-4-8 Advanced SAR Techniques 213

6-4-9 Description of an SAR Sensors 214

6-4-10 Applications of Imaging Radars 218

6-5 Nonimaging Radar Sensors: Scatterometers 221

6-5-1 Examples of Scatterometer Instruments 222

6-5-2 Example of Scatterometer Data 229

6-6 Nonimaging Radar Sensors: Altimeters 230

6-6-1 Examples of Altimeter Instruments 231

6-6-2 Altimeter Applications 233

6-6-3 Imaging Altimetry

6-6-4 Wide Swath Ocean Altimeter 234

6-7 Nonconventional Radar Sensors 236

6-8 Subsurface Sounding

Exercises 238

References and Further Readings 239

CHAPTER 7 OCEAN SURFACE SENSING 242

7-1 Physical Properties of the Ocean Surface 242

7-1-1 Tides and Currents 243

7-1-2 Surface Waves 244

7-2 Mapping of the Ocean Topography 248

7-2-1 Geoid Measurement 249

7-2-2 Surface Wave Effects 251

7-2-3 Surface Wind Effects

7-2-4 Dynamic Ocean Topography

7-2-5 Acillary Measurements 252

7-3 Surface Wind Mapping 252

7-3-1 Observations Required 253

7-3-2 Nadir Observations 254

7-4 Ocean Surface Imaging 257

7-4-1 Radar Imaging Mechanisms 257

7-4-2 Examples of Ocean Features on Radar Images 260

7-4-3 Imaging of Sea Ice 260

7-4-4 Ocean Color Mapping 263

7-4-5 Ocean Surface Temperature Mapping

7-4-6 Ocean Salinity Mapping

Exercises 267

References and Further Reading 270

CHAPTER 8 BASIC PRINCIPLES OF ATMOSPHERIC SENSING AND RADIATIVE TRANSFER 273

8-1 Physical Properties of the Atmosphere 273

8-2 Atmospheric Composition 277

8-3 Particulates and Clouds 279

8-4 Wave Interaction Mechanisms in Planetary Atmospheres 279

8-4-1 Resonant Interactions 279

8-4-2 Spectral Line Shape 284

8-4-3 Nonresonant Absorption 287

8-4-4 Nonresonant Emission 289

8-4-5 Wave Particle Interaction, Scattering 289

8-4-6 Wave Refraction 290

8-5 Optical Thickness 291

8-6 Radiative Transfer Equation 292

8-7 Case of a Nonscattering Plane Parallel Atmosphere 294

8-8 Basic Concepts of Atmospheric Remote Sounding 296

8-8-1 Basic Concept of Temperature Sounding 296

8-8-2 Basic Concept of Composition Sounding 298

8-8-3 Basic Concept of Pressure Sounding 298

8-8-4 Basic Concept of Density Measurement 298

8-8-5 Basic Concept of Wind Measurement

Exercises 298

References and Further Reading 299

CHAPTER 9 ATMOSPHERIC REMOTE SENSING IN THE MICROWAVE REGION 300

9-1 Microwave Interactions with Atmospheric Gases 300

9-2 Basic Concept of Downlooking Sensors 302

9-2-1 Temperature Sounding 303

9-2-2 Constituent Density Profile: Case of Water Vapor 307

9-3 Basic Concept for Uplooking Sensors 311

9-4 Basic Concept for Limblooking Sensors 313

9-5 Inversion Concepts 316

9-6 Basic Elements of Passive Microwave Sensors 317

9-7 Surface Pressure Sensing 320

9-8 Atmospheric Sounding by Occultation 320

9-9 Microwave Scattering by Atmospheric Particles 322

9-10 Radar Sounding of Rain 323

9-11 Radar Equation for Precipitation Measurement

9-12 The Tropical Rainfall Measuring Mission (TRMM)

9-13 Rain Cube

9-14 Cloudsat

9-15 Cassini Microwave Radiometer

9-16 Juno Microwave Radiometer

Exercises 326

References and Further Reading 327

CHAPTER 10 MILLIMETER AND SUBMILLIMETER SENSING OF ATMOSPHERES 330

10-1 Interaction with Atmospheric Constituents 330

10-2 Downlooking Sounding 334

10-3 Limb Sounding 336

10-4 Elements of a Millimeter Sounder

10-5 Submillimeter Atmospheric Sounder

Exercises 339

References and Further Reading 343

CHAPTER 11 ATMOSPHERIC REMOTE SENSING IN THE VISIBLE AND INFRARED 344

11-1 Interaction of Visible and Infrared Radiation with the Atmosphere 344

11-1-1 Visible and Near-Infrared Radiation 344

11-1-2 Thermal Infrared Radiation 348

11-1-3 Resonant Interactions 350

11-1-4 Effects of Scattering by Particulates 350

11-2 Downlooking Sounding 353

11-2-1 General Formulation for Emitted Radiation 353

11-2-2 Temperature Profile Sounding 354

11-2-3 Simple Cases Weighting Functions 356

11-2-4 Weighting Functions for Off Nadir Observations 358

11-2-5 Composition Profile Sounding 358

11-3 Limb Sounding 359

11-3-1 Limb Sounding by Emission 360

11-3-2 Limb Sounding by Absorption 362

11-3-3 Illustrative Example: Pressure Modulator Radiometer 362

11-3-4 Illustrative Example: Fourier Transform Spectroscopy 363

11-4 Sounding of Atmospheric Motion 365

11-4-1 Passive Techniques 368

11-4-2 Passive Imaging of Velocity Field: Helioseismology

11-4-3 Multiangle Imaging of SpectroRadiometer (MISR) 372

11-4-4 Active Techniques 373

11-5 Atmospheric Sensing at Very Short Wavelengths

Exercises 375

References and Further Reading 375

CHAPTER 12 IONOSPHERIC SENSING 379

12-1 Properties of Planetary Ionospheres 379

12-2 Wave Propagation in Ionized Media 381

12-3 Ionospheric Profile Sensing by Topside Sounding 384

12-4 Ionospheric Profile by Radio Occultation

Exercises 386

References and Further Reading 387

APPENDIX A USE OF MULTIPLE SENSORS FOR SURFACE OBSERVATIONS 388

APPENDIX B SUMMARY OF ORBITAL MECHANICS RELEVANT TO REMOTE SENSING 393

B-1 Circular Orbits 393

B-1-1 General Characteristics 393

B-1-2 Geosynchronous Orbits 395

B-1-3 Sun-Synchronous Orbits 395

B-1-4 Coverage 399

B-2 Elliptical Orbits 402

B-3 Orbit Selection

Exercises 404

APPENDIX C SIMPLIFIED WEIGHTING FUNCTIONS 405

C-1 Case of Downlooking Sensors (Exponential Atmosphere) 405

C-2 Case of Downlooking Sensors (Linear Atmosphere) 406

C-3 Case of Upward Looking Sensors 407

APPENDIX D COMPRESSION OF A LINEAR FM CHIRP SIGNAL

INDEX 409