Date Added: Mar 2011
In this paper, based on phase-only perturbation method, an innovative up-link Multiple-Intput Multiple-Output Spatial Division Multiple Access (MIMO-SDMA) optimization technique of smart antennas by is proposed. Particle Swarm Optimization (PSO) algorithm is used to search the optimal weighting vector of the phase shift perturbations for array factor. The deduced radiation pattern formulas available for searching optimal solutions are used to search the optimal weighting vector of the array factor of a smart antenna. The design for an optimal radiation pattern of a smart antenna can not only adjustably suppress interferers by placing nulls at the directions of the interfering sources but also provide maximum main lobes in the directions of the desired signals at the same time, i.e., to maximize the Signal to Interference Ratio (SIR).