Performance of WCDMA systems based on a novel generalized selective combining diversity technique

Generalized selective combining (GSC) is a hybrid diversity technique involving first selective combining (SC) followed by maximal ratio combining (MRC). In this paper we study a new technology based on bit log-likelihood ratio (BLLR) which is better than the traditional GSC based on signal-to-noise ratio (SNR) in performance. WCDMA is one of the key technologies of the third-generation mobile communication and the average bit-error rate (BER) performance of a MQAM WCDMA system combined with space-time block coding (STBC), 2D-RAKE receiver and the new GSC on correlated Nakagami fading channels has been investigated. The simulation results show that the BLLR scheme is superior to the SNR scheme since it minimizes the BER of WCDMA systems. With the increase of the multipath components, the performance of system is improved significantly. Moreover, the system which possesses the smaller rate of average path decay factor exhibits the higher diversity order.