Evaluation of chip space-time block coding DS-WCDMA in time-varying channels

In this paper, we investigate the performance of the downlink of a wideband code division multiple access system employing space-time block coding in a time-varying multipath channel. Space-time block coding is applied at the chip level to improve the robustness of the system to fading envelope variations. Simulation results show that the presented scheme offers considerable diversity gain even for high mobility users transmitting low data rate, outperforming a system employing symbol level space-time block coding in time-variant channels.