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Underwater acoustic imaging by wideband signal

This paper discusses the image reconstruction of underwater objects by large time-bandwidth product acoustic signals or wideband signals. It is shown that the principle of imaging by wideband signal is generalized range-Doppler imaging. This paper shows that the signal with wideband ambiguity function of the 'thumbtack type' is the optimum waveform for imaging for time scales very close to 1, and a digital simulation is used to verify it. The resolution ability of the imaging is analyzed. Finally the differences between the wideband imaging and synthetic aperture sonar are discussed.