Passive azimuth estimation using directional sensors in a cluster

This paper investigates the feasibility of a novel receiver system that can be deployed with a single sonobuoy for estimating the azimuthal angle of an underwater acoustic source. The azimuth estimation is based on energy information in signals received at two directional sensors in the receiver in a direct and surface-reflected environment. Expressions for the bias and variance of the azimuth estimator are derived. The results of the study show that the bias of the energy-based azimuth estimator can be predicted and then can be removed, and that its variance error is quite small. The theoretical development is corroborated with Monte Carlo simulations