The acoustic world of odontocete biosonar and technical sonar

Bats, toothed whales (odontocetes), and man-made sonar all use the same acoustical principles of echo-location. The fundamental components of these systems include transmitter frequency response, tailored waveforms, properties of a propagation medium, clutter, background noise, target strength, and receiver properties. Across all of these elements, there are very large differences (i.e., underwater versus in-air propagation). This gives rise to several interesting questions about the performance of these sonar systems. For example, given the bandwidth and duration of transmitted signals for bats and odontocetes, what are the relative target strengths/maximum imparted Doppler shifts for common prey types? How does the ambiguity function of the echo compare to these target sizes and relative Doppler shifts? What effect does the medium has and how do these systems adapt to clutter, interferers, and noise? This talk will focus on the underwater aspects of these systems which include (i) the properties of the underwater propagation medium, (ii) the geometry and material of the boundaries that limit the underwater propagation channel (this includes targets of interest and clutter), and (iii) the time-frequency and spatial properties of the underwater sources.