Performance Trade-Offs Among Optimized Beamforming Techniques for Smart Antenna System

Abstract

Smart antenna is a promising technology for the efficient utilization of limited Radio Frequency (RF) spectrum, improved system capacities and wireless communications through the implementation of Space Division Multiple Access (SDMA). Smart antenna radiation patterns are controlled via beamforming algorithms exploiting sophisticated spatial processing techniques based upon certain optimum criteria. This paper highlights the implications of optimum beamforming techniques for achieving high data speed rates and coverage area in cellular communication networks. In this paper, optimum beamforming algorithms have been analysed such as Multiple Sidelobe Canceller (MSC), Minimum Variance Distortionless Response (MVDR) and Minimum
Mean Square Error (MMSE) respectively. A trade-off analysis of various array performance metrics has also been presented among three beamforming techniques. Simulation results reveal that beamforming minimizes the interference power considerably by selecting optimum weights. The results illustrate that MMSE beamformer is helpful in mitigating Non-Line of Sight (NLOS) fading effects while MVDR beamformer has good performance in Line-of-Sight (LOS)fading environment. Moreover, MMSE beamformeroutperforms than other techniques with very narrower Half Power Beamwidth (HPBW) and Null-to-Null Beamwidth (NNBW). Depending on the application, one of the techniques is carefully chosen for deployment in smart base station antenna for cellular communication networks.