The Maximin Adaptive-Array Algorithm for Direct-Sequence Systems

An adaptive-array algorithm that suppresses interference in a direct-sequence system is proposed. The maximin algorithm differs from alternative algorithms in that it requires neither training sequences, directional information, decision-directed adaptation, nor elaborate computations such as eigenanalysis. The algorithm is derived and implementation details of the maximin processor in a direct-sequence system are explained. A convergence analysis establishes bounds on the adaptation constant and justifies the adaptation sequence used in the maximin algorithm. Simulation experiments confirm that the algorithm supplements the direct-sequence processing gain with a large amount of additional interference suppression. The simulation results demonstrate the robust performance of the algorithm for various array configurations, numbers of interference signals, interference levels, and fading conditions