Author : Swapnil M Hirikude and A.N.Jadhav

The demand for wireless mobile communications services is growing at an explosive rate, the high demand for wireless communication services in 3G and now 4G need more system capacity. The most elementary solution would be to increase bandwidth; however, this becomes even more challenging as the electromagnetic spectrum is becoming increasingly congested. The frequency reuse concept increases capacity however, increasing the number of cells to accommodate growing subscriber needs is not effective and not an economical option. This has led to development of new technologies that exploit space selectivity. This is done through smart-antenna arrays and the associated adaptive beam forming algorithms. In reality, antennas are not smart; it is the digital signal processing, along with the antenna, which makes the system smart. When smart antenna with Adaptive beamforming is deployed in mobile communication using either time division multiple access (TDMA) or code division multiple access (CDMA) environment, exploiting time slot or assigning different codes to different users respectively, it radiates beam towards desired users only. Each beam becomes a channel, thus avoiding interference in a cell. Smart-antenna systems provide opportunities for higher system capacity and improved quality of service. A new beamforming (Hybrid) technique using a pre-filtering process that decreases noise and interference effects to improve performance of cellular systems is illustrated here. This paper presents e comprehensive analysis ththe results obtained by applying prefiltering process to the most researched LMS non blind beam forming algorithm.

Keywords: Smart Antenna, DOA, Beamforming, Prefilter, LMS.

Article published in International Journal of Current  Engineering  and Technology, Vol.4,No.3 (June- 2014)