Extracting the time domain Green's function from ocean ambient noise using acoustic vector sensors.

A function that closely resembles the two-point time-domain Green's function (TDGF) representing the time delays associated with multipath between the two sensors can be recovered by correlating the noise field measured by two sensors. Here, a technique for extracting the TDGF from ambient ocean noise using acoustic vector sensors is presented. Experimental results suggest that the averaging time to extract TDGF is greatly reduced if sound pressure sensors (hydrophones) are replaced by acoustic vector sensors. The direct arrival and bottom bounce arrival were extracted successfully with only 1 min of vertical velocity data, while the bottom bounce arrival was not extracted with even 10 min of sound pressure data.