Volume -I , Issue -III, February 2014

BEAM STEERING IN ANTENNAS USING NOVEL LOW COMPLEX ADAPTIVE ALGORITHMS

P . V . Ramana and V . Saritha

An adaptive antenna system consists of a combination of multiple antenna elements with a signal-pr ocessing capability to optimize its radiation and/or reception pattern automatically in response to the signal environment. In a telecommunication system, adaptive antenna system is the port through which radio frequency (RF) energy is coupled fr om the transmitter to the environment and, in reverse, to the receiver from the environment.In this paper ,an efficient and simple adaptive beam steering technique is presented. The proposed method is based on Least Mean Square(LMS) algorithm, provides a comprehensive and detailed treatment of the signal model used for beam forming. In order to improve the convergence rate of LMS algorithm in smart antenna system, this paper pr oposes the Block Based Normalized LMS (BBNLMS) algorithm. The performance of the BBNLMS algorithm in the presence of Multi path effects and multiple users is analyzed using MATLAB simulations. Simulation results confirm that the convergence rate and error reduction of BBNLMS is superor than conventional LMS algorithm.

smart antenna, LMS, BBNLMS, DOA, convergence rate

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