Generalization of the subspace-based array shape estimations

This work describes a nonplane wave signal model for array shape estimation in ocean environments. Though existing array shape estimation methods, which utilize reference sources, show good performance in the environment where plane wave assumption is satisfied, their performances are degraded significantly in more realistic nonplane wave situation. The proposed subspace-based array shape estimation method, which generalizes the conventional subspace fitting method, works very well for both plane wave and nonplane wave environments. The Cramer-Rao lower bound is investigated to analyze the theoretical lower bound of the variance of the estimation. The simulation results indicate that the proposed method correctly estimates the shape of perturbed array regardless of reference source location.