Contents
3.2.3 Range profile complexity 108
3.2.4 Comparison of range profiles and optical images 109
3.3 Overview of range profiling process 109
3.3.1 Introduction 109
3.3.2 Measurement of target signature 110
3.3.3 Target signature database 110
3.3.4 Signature conditioning and recognition algorithms 112
3.4 High-range resolution radar pulse 112
3.5 Stepped frequency radar 113
3.5.1 Synthesing a wideband pulse 113
3.5.2 Measuring target signature 115
3.5.3 Stepped frequency signature characteristics 119
3.5.4 Operation in clutter 122
3.5.5 Motion compensation 123
3.5.6 Technology for supporting stepped frequency
applications 123
3.5.7 Stepped frequency conclusions 123
3.6 Wideband pulse compression 124
3.6.1 Introduction 124
3.6.2 Linear frequency modulation waveform 128
3.6.3 Non-linear frequency modulation 131
3.6.4 Phase coded waveforms 132
3.6.5 Noise-like waveforms 133
3.7 Stretch 134
3.7.1 Stretch technique 134
3.7.2 Range coverage 135
3.7.3 Range-Doppler coupling 136
3.7.4 Digitiser bandwidth 137
3.8 Bandwidth segmentation 139
3.8.1 Concept 139
3.8.2 Chirp segmentation 140
3.8.3 Combining segmented waveforms 141
3.8.4 Bandwidth segmentation techniques 142
3.8.5 Bandwidth segmentation conclusions 142
3.9 Summary of high-range resolution waveforms 142
References 144
4 High cross-range resolution techniques 147
4.1 Introduction 147
4.2 Doppler beam sharpening 148
4.2.1 Real beam map 148
4.2.2 Doppler beam sharpening concept 149
4.3 Synthetic aperture radar 151
4.3.1 Concept 151
4.3.2 SAR Doppler frequency shift 151
