Part I Sonar and Underwater Acoustics |
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1 Introduction to Underwater Acoustic Signal Processing |
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3 | (30) |
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1.1 Overview of Underwater Acoustic Signal Processing |
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3 | (24) |
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4 | (2) |
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1.1.2 Common Applications |
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6 | (1) |
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1.1.3 Signal Processing in Underwater Acoustics |
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7 | (2) |
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1.1.4 Development Process for Novel Applications |
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9 | (1) |
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1.1.5 Example Signals of Interest |
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10 | (5) |
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1.1.6 Examples of Signal and Information Processing |
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15 | (18) |
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16 | (2) |
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18 | (3) |
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21 | (3) |
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24 | (3) |
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1.2 Intended Use and Organization of This Book |
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27 | (4) |
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31 | (2) |
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2 Sonar Systems and the Sonar Equation |
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33 | (62) |
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33 | (1) |
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2.2 Remote Sensing with Sonar Systems |
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33 | (23) |
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2.2.1 Components of a Sonar System |
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34 | (2) |
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2.2.2 Monostatic, Bistatic, and Distributed Sonar Systems |
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36 | (1) |
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2.2.3 Localization: Estimating the Position of a Sound or Scattering Source |
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37 | (8) |
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2.2.3.1 Active vs. Passive Localization |
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38 | (1) |
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2.2.3.2 Array Design and Angle Estimation |
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39 | (1) |
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2.2.3.3 Localization with Distributed and Moving Sonar Systems |
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40 | (3) |
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2.2.3.4 Localization and the Effects of Propagation |
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43 | (2) |
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2.2.4 Bistatic Active Sonar |
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45 | (3) |
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2.2.4.1 Active Sonar Resolution Cell |
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47 | (1) |
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2.2.5 Doppler Scale and Shift |
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48 | (6) |
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2.2.5.1 Doppler Effect via Waveform and Platform Trajectories |
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51 | (3) |
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2.2.6 Doppler Sensitive and Insensitive Waveforms |
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54 | (2) |
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56 | (35) |
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58 | (2) |
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2.3.2 The Basic Passive Sonar Equation |
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60 | (7) |
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2.3.2.1 Example: Passive Submarine Radiated Noise Detection |
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66 | (1) |
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2.3.3 The Basic Active Sonar Equation |
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67 | (6) |
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2.3.3.1 Example: Reverberation- and Noise-Limited Active Sonar Detection |
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71 | (2) |
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2.3.4 Summary of Sonar Equation Terms |
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73 | (2) |
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2.3.5 Relating SNR to Detection Performance: Detection Threshold |
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75 | (10) |
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2.3.5.1 Gaussian-Fluctuating Signal |
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76 | (2) |
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2.3.5.2 Non-fluctuating or Deterministic Signal |
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78 | (1) |
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2.3.5.3 Extensions to Other Signal and Noise Models |
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79 | (1) |
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2.3.5.4 Example Signal-Model Performance Comparison |
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80 | (1) |
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2.3.5.5 Detection Threshold (DT) |
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81 | (4) |
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2.3.6 Relating SNR to Estimation Performance |
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85 | (2) |
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2.3.7 Other Applications of the Sonar Equation |
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87 | (8) |
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2.3.7.1 Signal Excess (SE) |
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88 | (2) |
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2.3.7.2 Figure of Merit (FOM) |
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90 | (1) |
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91 | (4) |
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95 | (108) |
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95 | (1) |
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3.2 Acoustic Wave Propagation in the Ocean |
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95 | (63) |
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3.2.1 Acoustical Field and Power Quantities |
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97 | (4) |
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3.2.1.1 Acoustic Pressure and Pressure Levels |
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98 | (1) |
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3.2.1.2 Particle Velocity |
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99 | (1) |
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3.2.1.3 Acoustic Intensity |
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100 | (1) |
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100 | (1) |
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3.2.1.5 Acoustic Energy Flux Density |
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101 | (1) |
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3.2.2 Propagation and Spreading |
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101 | (10) |
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3.2.2.1 The Wave Equation, Spherical Waves, and Spherical Spreading |
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102 | (2) |
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3.2.2.2 Periodic Signals, Wavelength, and Wavenumber |
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104 | (2) |
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3.2.2.3 Cylindrical Spreading |
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106 | (1) |
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107 | (2) |
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3.2.2.5 Near-Field and Far-Field Propagation |
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109 | (2) |
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3.2.3 Sound Projection and Propagation |
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111 | (9) |
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3.2.3.1 Inhomogeneous Wave Equation and the Channel Impulse Response |
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111 | (3) |
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3.2.3.2 Helmholtz Equation and Channel Frequency Response |
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114 | (1) |
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3.2.3.3 Doppler Effect via the Inhomogeneous Wave Equation |
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115 | (3) |
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3.2.3.4 Source Factor and Source Level (SL) |
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118 | (2) |
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3.2.4 Propagation Loss (PL) |
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120 | (4) |
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3.2.4.1 Propagation Loss for Different Spreading Models |
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121 | (1) |
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3.2.4.2 Propagation Loss and the Channel Frequency Response |
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122 | (1) |
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3.2.4.3 Coherent and Incoherent Propagation Loss |
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123 | (1) |
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3.2.5 Absorption and Dispersion |
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124 | (1) |
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124 | (1) |
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124 | (1) |
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3.2.6 Sound-Speed, Snell&apso;s Law, and Refraction |
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125 | (6) |
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3.2.6.1 Sound Speed Profiles and Ray Tracing |
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128 | (3) |
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3.2.7 Boundaries and Reflection Loss |
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131 | (17) |
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3.2.7.1 Boundary Conditions Between Layers |
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132 | (1) |
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3.2.7.2 Constant-Density Layers |
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133 | (1) |
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3.2.7.3 Reflection at the Ocean Surface |
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134 | (2) |
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3.2.7.4 Reflection at the Ocean Bottom |
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136 | (2) |
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3.2.7.5 Total Internal Reflection and Phase Change |
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138 | (4) |
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3.2.7.6 Rough Surface Reflection |
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142 | (6) |
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3.2.8 Rays and Modes in Shallow Water |
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148 | (8) |
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3.2.8.1 Ray-Based Solution and Multipath |
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149 | (1) |
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3.2.8.2 Mode-Based Solution |
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150 | (4) |
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3.2.8.3 Dispersion in a Waveguide |
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154 | (2) |
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156 | (2) |
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158 | (6) |
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3.3.1 Overview and Ambient Noise Spectrum Curves |
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158 | (2) |
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3.3.1.1 Converting Spectrum Rates of Change from per Octave to per Decade |
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160 | (1) |
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160 | (1) |
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3.3.3 Low Frequency: Distant Shipping Noise |
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161 | (1) |
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3.3.4 Low to High Frequency: Wind-Related Surface Noise |
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162 | (1) |
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3.3.5 Very High Frequency: Thermal Noise |
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163 | (1) |
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3.3.6 Spatio-Temporal and Statistical Properties of Ambient Noise |
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164 | (1) |
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3.4 Scattering from Objects: Target Echoes and Target Strength |
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164 | (16) |
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3.4.1 Target Strength (TS) |
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165 | (4) |
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3.4.1.1 Relationship to Radar Cross Section |
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168 | (1) |
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3.4.2 Target Impulse Response |
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169 | (3) |
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3.4.2.1 Impulse Response of a Rigid Sphere |
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170 | (2) |
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3.4.3 Scattering from Objects: The ka Dependence |
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172 | (8) |
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3.4.3.1 Rayleigh Scattering Regime (ka 1) |
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173 | (1) |
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3.4.3.2 Geometric Scattering Regime (ka 1) |
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174 | (3) |
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3.4.3.3 Exact Modal Solutions |
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177 | (3) |
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180 | (16) |
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3.5.1 Sources of Reverberation |
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182 | (1) |
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3.5.2 Volume Reverberation |
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182 | (4) |
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3.5.3 Boundary Reverberation |
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186 | (3) |
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3.5.4 Signal to Reverberation Ratio |
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189 | (1) |
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3.5.5 Statistical Characterization of Reverberation |
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190 | (1) |
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3.5.6 Spectral Properties of Reverberation |
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191 | (2) |
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3.5.7 Reverberation from a Moving Source |
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193 | (3) |
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196 | (7) |
Part II Systems, Signal Processing and Mathematical Statistics Background |
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4 Linear Systems and Signal Processing |
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203 | (48) |
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203 | (1) |
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4.2 Linear-Time-Invariant (LTI) Systems and Convolution |
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203 | (5) |
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4.2.1 Impulse Response of an LTI System |
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204 | (3) |
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4.2.2 Frequency Response of an LTI System |
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207 | (1) |
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208 | (7) |
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4.3.1 Inverse Fourier Transform |
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209 | (2) |
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4.3.2 Properties of the Fourier Transform |
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211 | (4) |
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215 | (1) |
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4.5 Signal Time-Bandwidth Product |
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216 | (3) |
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4.6 Converting Analog Signals to Digital Signals |
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219 | (6) |
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4.6.1 Sampling and Aliasing |
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219 | (4) |
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223 | (2) |
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4.7 Discrete-Time Signals and Systems |
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225 | (3) |
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4.7.1 Fourier Transform of a Discrete-Time Signal |
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226 | (1) |
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4.7.2 Properties of the Fourier Transform of Discrete-Time Signals |
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227 | (1) |
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4.8 Discrete and Fast Fourier Transforms (DFT and 1F1) |
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228 | (3) |
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4.9 Discrete-Time Filtering (LPF, HPF, and BPF) |
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231 | (8) |
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4.9.1 FIR and IIR Filters |
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232 | (2) |
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234 | (2) |
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4.9.3 Bandpass and High-Pass Filters |
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236 | (1) |
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4.9.4 FIR Filter Implementation |
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237 | (2) |
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4.10 Windowing and Window Functions |
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239 | (7) |
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4.10.1 Rectangular, Uniform, or Boxcar Window |
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242 | (1) |
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243 | (1) |
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243 | (1) |
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244 | (1) |
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245 | (1) |
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245 | (1) |
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246 | (1) |
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4.11 Decimation and Interpolation |
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246 | (3) |
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249 | (2) |
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5 Mathematical Statistics |
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251 | (56) |
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251 | (1) |
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251 | (2) |
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253 | (20) |
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5.3.1 Random Variables, Distributions, and Densities |
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253 | (4) |
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5.3.2 Moments and Expectations |
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257 | (2) |
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5.3.3 Functions of Random Variables |
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259 | (3) |
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5.3.4 Simulating Random Variables |
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262 | (1) |
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5.3.5 Histogram Estimates of the PDF and CDF |
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263 | (2) |
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5.3.6 Multiple Random Variables, Joint Densities, and Independence |
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265 | (3) |
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5.3.7 Central Limit Theorem (CLT) |
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268 | (1) |
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5.3.8 Conditional Distributions and Bayes&apso; Theorem |
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269 | (2) |
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5.3.9 Transform-Domain Functions |
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271 | (2) |
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5.3.9.1 Moment Generating Function |
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271 | (1) |
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5.3.9.2 Characteristic Function |
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272 | (1) |
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5.3.9.3 Cumulant Generating Function |
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272 | (1) |
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273 | (8) |
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5.4.1 Stationarity and Ergodicity |
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275 | (3) |
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5.4.2 Power Spectral Density |
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278 | (3) |
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5.5 Complex Random Variables and Random Processes |
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281 | (3) |
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5.6 Common Statistical Distributions |
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284 | (19) |
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5.6.1 Bernoulli Distribution |
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285 | (1) |
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5.6.2 Binomial Distribution |
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286 | (1) |
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5.6.3 Poisson Distribution |
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286 | (1) |
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5.6.4 Uniform Distribution |
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287 | (1) |
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288 | (1) |
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5.6.6 Gaussian or Normal Distribution |
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289 | (1) |
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5.6.7 Complex Gaussian Distribution |
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290 | (1) |
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5.6.8 Multivariate Gaussian Distribution |
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291 | (1) |
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5.6.9 Complex Multivariate Gaussian Distribution |
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291 | (1) |
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5.6.10 Exponential Distribution |
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292 | (1) |
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5.6.11 Gamma Distribution |
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293 | (1) |
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5.6.12 Rayleigh Distribution |
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294 | (1) |
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5.6.13 Rician Distribution |
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295 | (1) |
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5.6.14 Chi-Squared Distribution |
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296 | (1) |
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5.6.15 Non-central Chi-Squared Distribution |
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297 | (1) |
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298 | (1) |
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5.6.17 Non-central F Distribution |
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299 | (1) |
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5.6.18 Weibull Distribution |
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300 | (1) |
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301 | (1) |
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5.6.20 Generalized Pareto Distribution |
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302 | (1) |
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5.6.21 Log Normal Distribution |
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303 | (1) |
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303 | (4) |
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6 Statistical Signal Processing |
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307 | (42) |
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307 | (1) |
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6.2 Signal Detection Theory |
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307 | (18) |
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6.2.1 Hypothesis Testing in Underwater Acoustics |
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308 | (1) |
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6.2.2 Performance Measures, Implementation, and Analysis of Detectors |
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309 | (7) |
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6.2.2.1 Receiver Operating Characteristic (ROC) Curves |
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312 | (2) |
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6.2.2.2 Estimating Pd and Pf |
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314 | (1) |
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6.2.2.3 Importance Sampling |
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315 | (1) |
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6.2.2.4 Equal-Error Point and Area Under the Curve |
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315 | (1) |
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6.2.3 Design of Detectors: Neyman-Pearson Optimal |
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316 | (2) |
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6.2.4 Composite Hypothesis Testing: Detecting When There Are Unknown Parameters |
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318 | (1) |
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6.2.5 Design of Detectors: Uniformly Most Powerful Tests and Invariance |
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319 | (1) |
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6.2.6 Design of Detectors: Small-Signal Situations |
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320 | (1) |
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6.2.7 Design of Detectors: Generalized Likelihood Ratio (GLR) |
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321 | (4) |
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6.2.7.1 Asymptotic Distribution of the GLR Detector Decision Statistic |
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324 | (1) |
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6.2.8 Design of Detectors: Bayesian Approaches |
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325 | (1) |
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325 | (20) |
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6.3.1 Point Estimation in Underwater Acoustics |
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326 | (1) |
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6.3.2 Performance Measures and Analysis of Estimators |
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327 | (2) |
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6.3.3 Cramer-Rao Lower Bound (CRLB) |
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329 | (6) |
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6.3.3.1 CRLB for Multiple Parameters |
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331 | (1) |
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6.3.3.2 CRLB for Transformations |
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332 | (2) |
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6.3.3.3 CRLB for a Multivariate Gaussian Model |
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334 | (1) |
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6.3.3.4 CRLB for a Complex Multivariate Gaussian Model |
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334 | (1) |
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6.3.4 Estimation Techniques: Maximum Likelihood |
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335 | (2) |
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6.3.4.1 Properties of the MLE |
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336 | (1) |
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6.3.5 Estimation Techniques: Method of Moments |
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337 | (3) |
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6.3.6 Estimation Techniques: Bayesian Inference |
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340 | (1) |
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6.3.7 Estimation Techniques: Expectation-Maximization (EM) Algorithm |
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341 | (3) |
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6.3.7.1 Example: Exponential Mixture |
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342 | (2) |
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6.3.8 Confidence Intervals and Bayesian Credible Sets |
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344 | (1) |
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345 | (4) |
Part III Detection in Underwater Acoustics |
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7 Underwater Acoustic Signal and Noise Modeling |
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349 | (108) |
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349 | (2) |
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7.2 Characterizing Underwater Acoustic Signals |
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351 | (16) |
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7.2.1 Signal Consistency and Knowledge |
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353 | (3) |
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7.2.2 Time-Frequency Characterization of the Signal |
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356 | (6) |
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7.2.2.1 Finite-Duration Signal Measurement as a Stationary Random Processes |
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358 | (1) |
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7.2.2.2 Narrowband, Broadband, and Bandpass Signals |
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359 | (3) |
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7.2.3 Effect of Propagation on Source-Signal Characterization |
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362 | (5) |
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7.2.3.1 Unknown and Random Phases |
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363 | (1) |
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7.2.3.2 Unknown and Random Amplitudes |
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364 | (3) |
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7.3 Bandpass and Baseband Representations of Signal and Noise |
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367 | (21) |
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368 | (3) |
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7.3.2 Basebanding and the Complex Envelope |
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371 | (6) |
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7.3.2.1 Signal Envelope and Instantaneous Intensity |
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373 | (1) |
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7.3.2.2 Different Ways to Baseband a Signal |
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374 | (1) |
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7.3.2.3 Basebanding a Signal Subject to Delay and Doppler |
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375 | (2) |
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7.3.3 Bandpass Signals and Linear Time-Invariant Systems |
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377 | (1) |
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7.3.4 Complex Envelope of Bandpass Noise |
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378 | (4) |
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7.3.5 Modeling the Complex Envelope After Sampling in Time |
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382 | (3) |
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7.3.5.1 Deterministic Signal Energy |
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382 | (1) |
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7.3.5.2 Noise Covariance Matrix |
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383 | (2) |
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7.3.6 Statistics of the Complex Envelope, Envelope, and Instantaneous Intensity |
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385 | (3) |
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7.3.6.1 Uniformly Random Phase |
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386 | (2) |
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7.4 Noise and Interference Models |
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388 | (41) |
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389 | (3) |
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392 | (11) |
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7.4.2.1 Reverberation as a Random Process |
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392 | (1) |
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7.4.2.2 Reverberation Autocorrelation Function |
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393 | (1) |
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7.4.2.3 Reverberation Power Spectral Density |
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394 | (2) |
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7.4.2.4 Doppler Spreading of Reverberation |
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396 | (7) |
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7.4.3 Heavy-Tailed Noise and Reverberation |
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403 | (26) |
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7.4.3.1 Effect of Beamforming and Matched Filtering on Reverberation Statistics |
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404 | (2) |
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7.4.3.2 Statistical Models for Heavy-Tailed Data |
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406 | (2) |
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408 | (5) |
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7.4.3.4 Poisson-Rayleigh Distribution |
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413 | (2) |
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7.4.3.5 Other Common Models |
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415 | (5) |
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7.4.3.6 Performance Bounds on Parameter Estimation |
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420 | (3) |
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7.4.3.7 Mixture Distributions |
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423 | (6) |
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7.5 Signal and Signal-Plus-Noise Statistical Models |
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429 | (23) |
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7.5.1 Deterministic Signal |
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430 | (5) |
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7.5.1.1 Probability of Detection |
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434 | (1) |
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7.5.1.2 Sum of Instantaneous-Intensity Samples |
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434 | (1) |
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7.5.2 Gaussian-Fluctuating Signal |
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435 | (2) |
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7.5.2.1 Probability of Detection |
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436 | (1) |
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7.5.2.2 Sum of Instantaneous-Intensity Samples |
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436 | (1) |
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437 | (3) |
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7.5.3.1 Probability of Detection |
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438 | (1) |
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7.5.3.2 Sum of Instantaneous-Intensity Samples |
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439 | (1) |
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7.5.4 Gamma-Fluctuating-Intensity (GFI) Signal |
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440 | (2) |
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7.5.4.1 Probability of Detection |
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441 | (1) |
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7.5.4.2 Sum of Instantaneous-Intensity Samples |
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442 | (1) |
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7.5.5 Hankel Transform for Signal-Plus-Noise PDFs and CDFs |
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442 | (3) |
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7.5.6 Approximations to the CDF of Signals in Heavy-Tailed Noise |
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445 | (12) |
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7.5.6.1 Signal in Gaussian Noise |
|
|
446 | (1) |
|
7.5.6.2 Three-Moment Shifted-Gamma (TMSG) Approximation |
|
|
446 | (2) |
|
7.5.6.3 Three-Moment Non-central-gamma (TMNCG) Approximation |
|
|
448 | (3) |
|
7.5.6.4 Sums of Instantaneous-Intensity Samples |
|
|
451 | (1) |
|
7.5.6.5 Signal and Noise Model Instantaneous-Intensity Moments |
|
|
452 | (1) |
|
|
452 | (5) |
|
8 Detecting Signals with Known Form: Matched Filters |
|
|
457 | (164) |
|
|
457 | (7) |
|
8.1.1 Introductory Examples |
|
|
459 | (5) |
|
8.2 Matched-Filter Detectors |
|
|
464 | (34) |
|
8.2.1 SNR Gain of the Matched Filter |
|
|
469 | (2) |
|
8.2.2 Detector for Signals with Known Form, Known Amplitude, and Known Phase |
|
|
471 | (4) |
|
8.2.3 Detector for Signals with Known Form and Unknown Phase |
|
|
475 | (2) |
|
8.2.4 Detector for Signals with Known Form and Uniformly Random Phase |
|
|
477 | (2) |
|
8.2.5 Detector for Signals with Known Form and Gaussian Amplitude Fluctuations |
|
|
479 | (2) |
|
8.2.6 Detector for Signals with Known Form and an Arbitrary Amplitude Distribution |
|
|
481 | (1) |
|
8.2.7 Detector for Signals with Known Form and a Rician Distributed Amplitude |
|
|
482 | (3) |
|
8.2.8 Detectors When Parameters Other Than Phase and Amplitude Are Unknown |
|
|
485 | (4) |
|
8.2.8.1 Detectors for Unknown Noise Parameters |
|
|
485 | (3) |
|
8.2.8.2 Detectors for Unknown Signal Parameters |
|
|
488 | (1) |
|
8.2.9 Noise-Normalized and Adaptive Matched Filters |
|
|
489 | (2) |
|
8.2.10 Effect of Oversampling on a Matched-Filter Detector |
|
|
491 | (3) |
|
8.2.11 False-Alarm Rate (FAR) |
|
|
494 | (4) |
|
8.2.11.1 FAR Under Oversampling |
|
|
497 | (1) |
|
8.3 Waveform Autocorrelation and Ambiguity Functions |
|
|
498 | (29) |
|
8.3.1 SNR Loss from Waveform Mismatch |
|
|
500 | (7) |
|
8.3.1.1 Coherent Matched Filter |
|
|
500 | (1) |
|
8.3.1.2 Quadrature Matched Filter |
|
|
501 | (1) |
|
8.3.1.3 The Complex Ambiguity Function and SNR Loss |
|
|
502 | (5) |
|
8.3.2 Ambiguity Functions |
|
|
507 | (3) |
|
8.3.2.1 Narrowband Signals |
|
|
508 | (1) |
|
|
509 | (1) |
|
8.3.3 Autocorrelation Functions |
|
|
510 | (1) |
|
|
511 | (4) |
|
8.3.4.1 Autocorrelation Function for a CW Pulse |
|
|
511 | (2) |
|
8.3.4.2 Ambiguity Function for a CW Pulse |
|
|
513 | (2) |
|
|
515 | (5) |
|
8.3.5.1 Autocorrelation Function for an LFM Pulse |
|
|
516 | (1) |
|
8.3.5.2 Narrowband Ambiguity Function for an LFM Pulse |
|
|
517 | (2) |
|
8.3.5.3 Wideband Ambiguity Function for an LFM Pulse |
|
|
519 | (1) |
|
|
520 | (7) |
|
8.3.6.1 Autocorrelation Function for an HFM Pulse |
|
|
522 | (2) |
|
8.3.6.2 Ambiguity Function for an HFM Pulse |
|
|
524 | (3) |
|
8.4 Beamforming as a Detection Process |
|
|
527 | (8) |
|
8.4.1 Plane Waves and Line Arrays |
|
|
527 | (1) |
|
8.4.2 Narrowband Beamformer |
|
|
528 | (3) |
|
8.4.2.1 Array Signal and Noise Models |
|
|
529 | (2) |
|
8.4.3 Array Beam Response and Beampattern |
|
|
531 | (2) |
|
8.4.4 Array Gain and Directivity |
|
|
533 | (2) |
|
8.5 Signal-Parameter Estimation Performance |
|
|
535 | (27) |
|
8.5.1 Waveform Resolution vs. Estimation Accuracy |
|
|
537 | (4) |
|
8.5.1.1 Resolution of the Standard Sonar Pulses |
|
|
537 | (3) |
|
8.5.1.2 Accuracy vs. Resolution |
|
|
540 | (1) |
|
8.5.2 Performance Bounds for Estimating Signal Strength and Phase |
|
|
541 | (4) |
|
8.5.3 Performance Bounds for Estimating Arrival Time |
|
|
545 | (8) |
|
8.5.3.1 Frequency-Modulated Pulses |
|
|
550 | (2) |
|
8.5.3.2 Continuous-Wave Pulses |
|
|
552 | (1) |
|
8.5.4 Performance Bounds for Estimating Doppler Scale |
|
|
553 | (5) |
|
8.5.4.1 Shaded CW-Pulse Example |
|
|
556 | (2) |
|
8.5.5 Performance Bounds for Joint Estimation of Arrival Time and Doppler Scale |
|
|
558 | (4) |
|
8.5.5.1 LFM-Pulse Example |
|
|
560 | (2) |
|
8.6 Normalization: Background Power Estimation |
|
|
562 | (22) |
|
8.6.1 Cell-Averaging CFAR Normalizer |
|
|
566 | (8) |
|
8.6.1.1 Decision-Threshold Analysis |
|
|
567 | (2) |
|
8.6.1.2 Equivalent Number of Independent Samples |
|
|
569 | (3) |
|
8.6.1.3 Performance Analysis and CFAR Loss |
|
|
572 | (2) |
|
8.6.2 Target Masking and False-Alarm-Rate Inflation |
|
|
574 | (1) |
|
8.6.3 Order-Statistic CFAR Normalizer |
|
|
575 | (9) |
|
8.6.3.1 Decision-Threshold Analysis |
|
|
577 | (1) |
|
8.6.3.2 Performance Analysis |
|
|
578 | (4) |
|
8.6.3.3 Which Order Statistic to Use? |
|
|
582 | (2) |
|
|
584 | (19) |
|
8.7.1 Doppler Filter Bank |
|
|
586 | (8) |
|
8.7.1.1 Probability of False Alarm in a Filter Bank |
|
|
587 | (1) |
|
8.7.1.2 Probability of Detection in a Filter Bank |
|
|
588 | (2) |
|
8.7.1.3 Doppler Filter Bank Example |
|
|
590 | (2) |
|
8.7.1.4 FFT Implementation of a CW-Pulse Doppler Filter Bank |
|
|
592 | (2) |
|
8.7.2 Reverberation in a Doppler Filter Bank |
|
|
594 | (5) |
|
8.7.2.1 Detection in Reverberation and Noise |
|
|
596 | (1) |
|
8.7.2.2 Reverberation Temporal-Support Function for CW and FM Pulses |
|
|
597 | (2) |
|
8.7.3 Normalization for CW Pulses |
|
|
599 | (4) |
|
8.8 Temporal Spreading and Incoherent Integration |
|
|
603 | (13) |
|
8.8.1 Energy Spreading Loss (ESL) |
|
|
604 | (6) |
|
8.8.2 Incoherent Integration |
|
|
610 | (15) |
|
8.8.2.1 Decision-Threshold Analysis |
|
|
612 | (2) |
|
8.8.2.2 Performance Analysis |
|
|
614 | (2) |
|
Appendix 8.A: Example MATLAB® Code for a Doppler Filter Bank |
|
|
616 | (1) |
|
|
617 | (4) |
|
9 Detecting Signals with Unknown Form: Energy Detectors |
|
|
621 | (122) |
|
|
621 | (4) |
|
|
625 | (57) |
|
9.2.1 Statistical Characterization of the Signal and Noise |
|
|
628 | (2) |
|
9.2.2 SNR After the Coherent Portion of Detection Processing |
|
|
630 | (2) |
|
9.2.3 Detector for Random Signals and Noise Having Constant Spectra in a Known Frequency Band |
|
|
632 | (6) |
|
9.2.3.1 The Basic Energy Detector and Its Performance Analysis |
|
|
634 | (4) |
|
9.2.4 Frequency-Domain Processing for Shaped Signal and Noise Spectra |
|
|
638 | (4) |
|
9.2.4.1 Decorrelation of DFT Bin Data |
|
|
640 | (2) |
|
9.2.5 Detectors for Random Signals with Known Spectra in a Known Frequency Band |
|
|
642 | (4) |
|
9.2.5.1 Optimal Detector for a Signal with a Known Spectrum |
|
|
642 | (1) |
|
9.2.5.2 Locally Optimal Detector for a Signal with a Known Spectral Shape |
|
|
643 | (1) |
|
9.2.5.3 Eckart Filter for Maximum Detection Index |
|
|
644 | (2) |
|
9.2.6 Detectors for Random Signals with Unknown Spectra in a Known Frequency Band |
|
|
646 | (2) |
|
9.2.6.1 Large and. Small Signal-to-Noise Spectral-Density Ratios |
|
|
646 | (1) |
|
9.2.6.2 Generalized Likelihood Ratio Energy Detector for an Unknown Signal Spectrum |
|
|
647 | (1) |
|
9.2.7 Performance of a Weighted-Sum Energy Detector for Gaussian Random Signals and Noise |
|
|
648 | (9) |
|
9.2.7.1 Exact Solution via the Characteristic Function |
|
|
651 | (1) |
|
9.2.7.2 Numerical Evaluation of the CDF from the Characteristic Function |
|
|
652 | (3) |
|
9.2.7.3 Gaussian Approximation |
|
|
655 | (1) |
|
9.2.7.4 Gamma Approximation |
|
|
656 | (1) |
|
9.2.7.5 Shifted Gamma Approximation |
|
|
656 | (1) |
|
9.2.8 Detectors for Random Signals with Unknown Spectra in an Unknown Frequency Band |
|
|
657 | (6) |
|
9.2.8.1 Modified Generalized Likelihood Ratio Energy Detector |
|
|
658 | (1) |
|
9.2.8.2 Power-Law Energy Detector |
|
|
659 | (4) |
|
9.2.9 Detectors for Deterministic Signals with Unknown or Partially Known Form |
|
|
663 | (6) |
|
9.2.9.1 Deterministic Signals with Unknown Structure in a Known Frequency Band |
|
|
664 | (2) |
|
9.2.9.2 Deterministic Signals with Partially Known Form |
|
|
666 | (2) |
|
9.2.9.3 Completely Unknown Deterministic Signals |
|
|
668 | (1) |
|
9.2.10 Time-Domain Energy Detector: Coherent and Incoherent Averaging |
|
|
669 | (7) |
|
9.2.10.1 Choosing the Coherent-Processing- Window Size and Spacing |
|
|
674 | (1) |
|
9.2.10.2 Choosing the Analysis Window Extent |
|
|
675 | (1) |
|
9.2.11 Detection Threshold for the Noise-Normalized Energy Detector |
|
|
676 | (6) |
|
9.2.11.1 Deterministic Signals |
|
|
677 | (2) |
|
9.2.11.2 Gaussian-Based Approximation for Gaussian Random Signals |
|
|
679 | (2) |
|
9.2.11.3 Gamma-Based Approximation for Gaussian Random Signals |
|
|
681 | (1) |
|
9.3 Normalization: Background Power Estimation |
|
|
682 | (16) |
|
9.3.1 Auxiliary Data for Narrowband and Broadband Processing |
|
|
683 | (2) |
|
9.3.2 Cell-Averaging Normalizer |
|
|
685 | (3) |
|
9.3.3 Exponential-Average Normalizers |
|
|
688 | (4) |
|
9.3.4 Weighted-Average Normalizers |
|
|
692 | (6) |
|
9.3.4.1 Characteristic Function of a Weighted-Average Background Estimate |
|
|
693 | (1) |
|
9.3.4.2 Single-Sample Normalizer Distribution, Characteristic Function and Moments |
|
|
693 | (5) |
|
9.4 Time-Delay Estimation |
|
|
698 | (23) |
|
9.4.1 Cross-Correlation Processing |
|
|
701 | (12) |
|
9.4.1.1 Inter-Sensor-Delay Estimation |
|
|
706 | (4) |
|
9.4.1.2 Cramer-Rao Lower Bound for Inter-Sensor Delay |
|
|
710 | (3) |
|
9.4.2 Autocorrelation Processing |
|
|
713 | (8) |
|
9.4.2.1 Estimating Parameters of a PSD |
|
|
714 | (1) |
|
9.4.2.2 Multipath-Delay Estimation |
|
|
715 | (5) |
|
9.4.2.3 Cramer-Rao Lower Bound for Multipath Delay |
|
|
720 | (1) |
|
9.5 Narrowband-Signal Parameter Estimation |
|
|
721 | (12) |
|
|
722 | (6) |
|
9.5.1.1 Estimation of the Frequency, Phase, and Amplitude of a Sinusoid |
|
|
723 | (2) |
|
9.5.1.2 Phase Estimator Distribution |
|
|
725 | (2) |
|
9.5.1.3 Cramer-Rao Lower Bounds |
|
|
727 | (1) |
|
9.5.2 Narrowband Gaussian Random Signals |
|
|
728 | (24) |
|
9.5.2.1 Cramer-Rao Lower Bounds |
|
|
729 | (3) |
|
9.5.2.2 Estimation of the Center Frequency and Bandwidth |
|
|
732 | (1) |
|
Appendix 9.A: Numerical Evaluation of the CDF of a Sum of Exponential Random Variables |
|
|
733 | (2) |
|
Appendix 9.B: Moments of the Modified GLR Energy Detector Decision Statistic |
|
|
735 | (1) |
|
Appendix 9.C: Algorithm for Estimating the Bandwidth and Center-Frequency of a Narrowband Random Signal in Noise |
|
|
736 | (3) |
|
|
739 | (4) |
|
10 Detecting Signals with Unknown Duration and/or Starting Time: Sequential Detectors |
|
|
743 | (76) |
|
|
743 | (4) |
|
10.2 Performance Measures for Sequential Signal Detectors |
|
|
747 | (5) |
|
10.3 Detectors for Signals with Known Duration and Known Starting Time |
|
|
752 | (6) |
|
10.3.1 M-of-N Detector: Binary Integration |
|
|
753 | (5) |
|
10.3.1.1 M-of-N Detector Design: Choosing Thresholds |
|
|
755 | (3) |
|
10.4 Detectors for Signals with Known Duration and Unknown Starting Time |
|
|
758 | (8) |
|
10.4.1 Sliding Incoherent Sum Detector |
|
|
760 | (3) |
|
10.4.2 Sliding M-of-N Detector |
|
|
763 | (3) |
|
10.5 Detectors for Long-Duration Signals |
|
|
766 | (27) |
|
10.5.1 Known Starting Time: Sequential Probability Ratio Test (SPRT) |
|
|
767 | (9) |
|
10.5.1.1 Decision Thresholds and Error Probabilities |
|
|
769 | (1) |
|
10.5.1.2 Average Sample Numbers for the SPRT |
|
|
770 | (4) |
|
10.5.1.3 Overshoot Corrections to the SPRT Average Sample Numbers |
|
|
774 | (2) |
|
10.5.2 Unknown Starting Time: Page&apso;s Test |
|
|
776 | (17) |
|
10.5.2.1 Average Sample Numbers for Page&apso;s Test |
|
|
780 | (4) |
|
10.5.2.2 Unity Roots of the Moment Generating Function |
|
|
784 | (2) |
|
10.5.2.3 ROC Curves and Asymptotic Performance of Page&apso;s Test |
|
|
786 | (3) |
|
10.5.2.4 Biasing a General Input to Page&apso;s Test |
|
|
789 | (2) |
|
10.5.2.5 Page&apso;s Test with Nuisance Parameter Estimation |
|
|
791 | (1) |
|
10.5.2.6 Overshoot Corrections to Page&apso;s Test Average Sample Numbers |
|
|
792 | (1) |
|
10.6 Detectors for Signals with Unknown, Intermediate Duration |
|
|
793 | (24) |
|
10.6.1 Known Starting Time: Sequential Probability Ratio Test (SPRT) |
|
|
795 | (9) |
|
10.6.1.1 SPRT Analysis by Quantization |
|
|
797 | (5) |
|
|
802 | (2) |
|
10.6.2 Unknown Starting Time: Page&apso;s Test |
|
|
804 | (13) |
|
10.6.2.1 Alternating Hypothesis Page&apso;s Test |
|
|
804 | (3) |
|
10.6.2.2 Page&apso;s Test Analysis by Quantization |
|
|
807 | (3) |
|
|
810 | (7) |
|
|
817 | (2) |
Index |
|
819 | |