Adaptive Beam Formation in Smart Antenna Using VSLMS and VSNLMS Algorithms for Side Lobe Level Reduction

Monisha Bairagya


In mobile communication using smart antenna, the capacity of a cellular network can be enhanced significantly. Adaptive beamforming is one of the critical issues in smart antenna. A comparative study of beamforming algorithms by using their variable step size parameter like, variable step size least mean square algorithm (VSLMS) and variable step size normalized least mean square algorithm (VSNLMS) are presented in this paper. Smart antennas of 8 elements and 10 elements linear array are considered here. It is found that using VSNLMS algorithm a lower side lobe level is achieved compared to VSLMS algorithm for various angles of desired user and undesired interferer.


Smart antenna; adaptive beamforming; VSLMS algorithm; VSNLMS algorithm; Side lobe reduction

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