Evaluation of potential transmit diversity schemes with iterative receivers in EDGE

In this paper we compare conventional and iterative receiver structures for transmit diversity schemes for frequency selective fading channels. As a practical example we consider an EDGE system with two transmitting and one receiving antennas. In particular, delay diversity (DD) and space-time block codes (STBC) for multipath channels are considered. It is shown that STBC in EDGE brings up to 3 dB gain, which is by 1-2 dB more than the gain provided by the DD. However, the SBTC diversity gain may not be fully utilized due to degradation of channel estimation accuracy. To improve the accuracy of channel estimates and the overall performance we consider receivers with iterative (turbo) estimation/detection. It is shown that iterative data processing in EDGE is more beneficial for STBC than for the DD.