Two-dimensional arrays with nonlinear elements

The use of sensors configured into various geometrical shapes called arrays are of fundamental importance in extracting temporal, spatial, frequency, and probability distribution information in underwater acoustic and other applications. This paper explores the effectiveness of a two-dimensional or planar array in extracting spatial and frequency information. The method utilizes a receiver which converts digitized data at the output of each element, which may be nonlinear, into its frequency components using a discrete-Fourier transform. The frequency components are then weighted and summed over all spatial elements. The objective of the optimum receiver is to choose the weights so that a performance measure is maximized. To combat non-Gaussian interference an ideal nonlinearity is introduced. Several examples are given comparing the performance of a receiver with and without an ideal nonlinearity in an impulsive or non-Gaussian noise environment.