A posteriori Rake finger selection in space-time coded CDMA systems

We present the optimal Rake finger selection criterion that minimizes the a posteriori probability of symbol error in space-time block coded code division multiple access (CDMA) systems. It can serve as a benchmark for the performance of all a posteriori Rake finger selection criteria. Then we present suboptimal, but more practical, finger selection criteria based on a posteriori symbol error probability bounds, and analyze the bit error probability as a function of constellation sizes and number of resolvable paths. Simulation results show that there is a significant gain over the traditional signal strength-based selection criterion