Performance of Over Constrained Channel Shortening Technique with Receive Diversity for MB-OFDM UWB System
Jen-Ming Wu and Hung-Wen Yang
International Symposium on Performance Evaluation of Computer and Telecommunication Systems (SPECTS 2007)
San Diego, California (USA), July 16-18, 2007
SPECTS_Summary
In this paper, we present an adaptive channel equalization scheme with receiver diversity for MB-OFDM Ultra-wide Band (MB-OFDM UWB) communication system. When the channel impulse response is longer than guarding interval, inter-symbol interference (ISI) will heavily degrade the system performance. Our scheme combines time domain impulse response shortening technique to deal with ISI, and multiple receive antennas for extra diversity gain. We propose to over constraint the desired length of shortening window of interest, and the BER can be improved by at least 4.4dB than conventional shortening techniques with shortening window equal to guard interval. Simulation results show the proposed scheme has better bit error rate (BER) performance over traditional UWB systems, which uses only frequency domain equalization. In addition, we also present the proposed channel shortening technique within the context of Single Input Multiple Output (SIMO) channel for additional receiver diversity gain.