Swarm Intelligence-based Optimal Design to Minimize the Sidelobe Level of Concentric Circular Antenna Array with Element Failures

In an antenna array due to large number of elements, there is always a possibility of failure of one or more elements in the array system, which results in increased SLL with distorted radiation pattern. Recovering the optimal beam pattern can be done by recalculating the amplitude distributions for array elements leaving the failed elements. Here, we have corrected the radiation pattern for concentric circular antenna array (CCAA) with central element, as CCAA with central element is widely implemented in smart antennas and mobile communication. A central element has been added to array to increase the steering capability of proposed array. It has been noticed that after failure of three or more number of elements with central element, there is a significant increase in side lobe level (SLL) which degrades the performance of the system. This distortion is corrected using bacterial foraging optimization, standard particle swarm optimization (PSO), and craziness-based particle swarm optimization (CRPSO) technique. The results of standard PSO and CRPSO are compared for a three ring CCAA with central element and it has been concluded that CRPSO gives the optimum result.