Multi-Path Combining Scheme for ISI Suppression in DS-UWB Systems

Ultra Wide-band (UWB) recently attracts much attention as an indoor short range high-speed wireless communication technology for next generation networks. Direct sequence spread ultra wide-band (DS-UWB) systems uses extremely short pulses and has the advantage of high path resolution and can get multi-path diversity if using rake structured receivers such as selective rake (S-rake) receiver. Unfortunately inter-symbol interference (ISI) will become a significant performance limitation when data rate is high. Several techniques such as rake receiver using minimum mean square error (MMSE) combining weights and frequency domain equalization (FDE) have been proposed to combat ISI. Different from these relatively complex methods, a practical multi-path combining scheme (MPC) to suppress ISI in DS-UWB systems is proposed in this paper. Simulation results show that our proposal outperforms the conventional S-rake receiver especially in a high signal to noise ratio (SNR) scenario