Algorithm Investigation for Large Adaptive Arrays.

Abstract : This report examines the influence of surplus antenna elements in an adaptive array. It is demonstrated that the judicious placement of a few extra antenna elements provides significant performance improvement. In particular, the speed of convergence is improved, and the quality of the antenna beam pattern is enhanced. Convergence rates and beam patterns are closely related to the eigenvalues of the antenna/signal system. A closed form expression is derived for the eigenvalues of a general antenna array with two jammers. From this, expressions for the convergence rate and the optimum beam pattern are found. Computer simulations are used to verify the theoretical developments concerning convergence rates and final beam patterns for a variety of element configurations. (Author)