Foray of Time-Frequency Techniques in Sonar Signal Processing

The advent of time-frequency methods have opened a whole new chapter in sonar signal processing. Current implementations are based on conventional techniques like FFT etc, which have many shortcomings. Although the Fourier transform yields perfect reconstruction of a broad class of signals, it does not necessarily provide a meaningful interpretation when the signal lacks global stationarity. Time-frequency methods allow us to observe how a spectral estimate evolves over time. In this paper, we have tried to explore the potential of time-frequency methods in sonar processing. The potential of three time-frequency methods namely WT, WVD & FrFT for different sonar functions have been explored in our work. Our simulations clearly demonstrate how these techniques outperform conventional methods, in each of the sonar application.