NULL PLACEMENT AND SIDELOBE SUPPRESSION IN FAILED ARRAY USING SYMMETRICAL ELEMENT FAILURE TECHNIQUE AND HYBRID HEURISTIC COMPUTATION

In this paper, we have addressed three major problems of uniform linear array in case of a sensor failure at any position. We assume that sensor position is known. The problems include increase in sidelobe levels, displacement of nulls and diminishing of null depth. The desired null depth is achieved by making the weight of symmetrical counterpart element passive. Genetic algorithm (GA) along with pattern search (PS) is used for reduction of sidelobe levels, and adjustment of nulls. Fitness function minimizing the error between the desired and estimated beam pattern along with null constraints is used. Simulation results for diversifled scenarios have been given to demonstrate the validity and performance of the proposed algorithm.