Radar Imaging of the Ocean Waves (eBook)

Front Cover 1
Radar Imaging of the Ocean Waves 4
Copyright Page 5
Table of Contents 6
Introduction 8
Chapter 1 Preliminary Notes on Radar Imaging 12
Chapter 2 Description of the Sea Surface 20
2.1 Sea Wave Spectra: General Relationships 20
2.2 Gravity Wave Spectra 25
2.3 Gravity–Capillary Wave Spectra 29
2.4 Realistic Ocean Surface and its Features 33
Chapter 3 Sea Scattering of Radio Waves 36
3.1 Sea Water Dielectric Constant and Electromagnetic Penetration Depth 36
3.2 Resonant Scattering 40
3.2.1 HF scattering and HF radars 40
3.2.2 Microwave scattering: two-scale model of the sea surface 47
3.3 Backscattering at Small Incidence Angles 56
3.3.1 Radar cross section at small incidence angles 57
3.3.2 Doppler spectrum at small incidence angles 64
3.4 Backscattering at Low Grazing Angles 73
Chapter 4 Microwave Doppler Spectrum at Moderate Incidence Angles 80
Chapter 5 Real Aperture Side-Looking Radar 92
5.1 Correlation Function of Backscattered Signal Intensity 92
5.2 Spatial Spectrum of Signal Intensity Slow Fluctuations 96
5.3 Fast Signal Fluctuations (Speckle Noise) 101
5.4 Inhomogeneous Roughness Imaging 106
Chapter 6 Synthetic Aperture Radar 110
6.1 Preliminary Estimates 110
6.2 SAR Image Correlation Function: General Relationships 112
6.3 Intensity of the SAR Signal Forming the “Image Itself” 115
6.4 Spectrum of the SAR Image of the Ocean 118
6.5.2 Velocity bunching mechanism: linear and quasi-linear approximations 127
6.5.3 Non-linear Velocity Bunching Mechanism 133
6.5.4 SAR imaging of the mixed sea 145
6.6 Speckle Noise in the SAR Image of the Ocean 148
6.7 Modified Spectral Estimate for the SAR Image of the Ocean 152
6.8 Peculiarities of the SAR Imagery of the Ocean Surface 158
6.8.1 SAR imaging of near-shore areas 158
6.8.2 Peculiarities of SAR imaging of ships and slicks 159
6.8.3 SAR as a tool for measurements of the near-surface wind speed 164
Chapter 7 Advanced Radars and Ocean Surface Imaging 170
7.1 SAR Interferometry and Remote Sensing of the Ocean Surface 170
7.2 Polarimetric Radars and the Problem of Remote Sensing of the Ocean Surface 180
Appendix A 188
Appendix B 190
Appendix C 192
References 194
Index 204