Pre/Post-Rake Diversity Combining for Transmit-Antennae Ultra-Wideband Communications

In this paper, we propose a principal ratio combining (PRC) pre/post-rake for ultra-wideband (UWB) systems with multiple transmit antennas. The combining weights of the PRC pre/post-Rake are determined by maximmng the signal-to-noise (SNR). In the case of one receive antenna, a singular value decomposition (SVD) pre/post-Rake with parallel subchannels can be implemented to increase the information capacity. Simulations show that the PRC pre/post-Rake and the SVD pre/post-Rake outperform the conventional rake in bit error rate (BER) performance and capacity, respectively.