Performance analysis of LMS and fractional LMS algorithms for smart antenna system

Abstract

Adaptive smart antennas are used as spatial filters for receiving the intended signals arriving from specific directions while nullifying the reception of undesired signals emanating from other directions. The LMS algorithm becomes most prominent technique used in several applications including beamforming of antenna array because of its simplicity and robustness. In this paper, a variant of LMS called Fractional LMS (FLMS) is proposed for updating the complex weights of the uniform circular array and its performance is compared with standard LMS algorithm. Simulation results show that FLMS converges faster than LMS and gives a good reduction of side lobes as compared to LMS algorithm.