Environmental symmetry breaking: An application of 3‐D matched‐field processing

Abstract

Self‐consistent simulations of matched‐field processing in a noisy three‐dimensional environment are produced by using the same numerical model for constructing the signal and correlated noise field. In principle, matched‐field processing in an asymmetric three‐dimensional (range‐ and azimuthal‐dependent) ocean provides the possibility of horizontal beamforming with a purely vertical array since the environment itself breaks the azimuthal symmetry of the vertical array. This scheme is called environmental symmetry breaking (ESB). As a demonstration, an ocean environment is used that has a portion of the Gulf Stream running through the area of interest together with a storm that produces a correlated horizontally (as well as vertically) anisotropic noise field. Linear and nonlinear matched‐field processing is considered for a vertical array. These simulations provide the first numerical evidence that ESB can be applied to the underwater detection problem.