Multi-beam steering with low grating lobes using optimized unequally spaced phased array

We propose a multi-beam steering technique with low grating lobes using unequally spaced phased array. The multi-beam steering is achieved using Array Division Multiplexing (ADM) technique. The unequal spacing distribution in ADM is optimized by the algorithm of particle swarm optimization (PSO) to minimize the grating lobes levels. The results show that the grating lobe level can be effectively reduced from 37.96% to 4.99% of the main lobe power using the proposed technique within the whole scanning range of the two steered beams.