Performance of a ray-based blind deconvolution algorithm for shipping sources in the Santa Barbara channel

Abstract

This paper investigates the performance of a ray-based blind deconvolution (RBD) algorithm for sources of opportunity, such as shipping noise, in an ocean waveguide recorded on a vertical line array (VLA). The RBD algorithm [Sabra et al., JASA,2010, EL42-7] relies on estimating the unknown phase of the source through wideband beamforming along a well-resolved ray path to approximate the environment’s Green’s Functions (or Channel Impulse responses) between the source and the VLA elements, as well with recovering the unknown radiated source signal. The RBD algorithm is tested here for shipping sources recorded in the Santa Barbara shipping channel (water depth ~550 meters). The four VLAs, with short (~ 15 meter) and long (~56 meter) apertures, were deployed between the north and south bound shipping lanes and collected acoustic data throughout a week in mid-September, 2016. Here, we discuss (1) the performance of conventional beamforming and adaptive (MVDR) beamforming when estimating ray-arrivals, (2) the ability of the RBD algorithm to deconvolve multiple VLAs using the only the same source phase estimated from a single VLA. The performance of the RBD results will be discussed in terms of accuracy of travel times and of the estimated Green’s Functions.