Performance of transmitter preprocessing assisted DSTTD over frequency-selective wireless communication channels

Double space-time transmit diversity (DSTTD) is currently one of the promising techniques for realizing both spatial diversity and multiplexing gains concurrently. In this paper, in contrast to previous work [6], we consider the performance of double space time transmit diversity (DSTTD) system with multi-user transmitter preprocessing (MUTP) over correlated and uncorrelated frequency-selective fading channels. The transmitter preprocessing (TP) is realized by singular value decomposition (SVD) which exploits the channel state information (CSI) of all the users at the base stations (BSs). This scheme can greatly bring down the complexity of the mobile terminals as well as obviate the need for complex MUDs. Specifically, we investigate the effects of four types of delay spread distributions on MUTP assisted DSTTD system. In a multi-cell scenario, users conflict co-channel interferences (CCI) which can severely degrade the system performance. It is shown through simulation that multi-user transmitter preprocessing (MUTP) can mitigate CCI in addition to retaining the low complexity nature of the mobile terminals. Comparisons for correlated and uncorrelated frequency-selective channels with and without TP are also provided.