Performance Analysis of DS-BPAM UWB System over Fading Channels - Uncoded and Coded Schemes

This paper investigates the performance of two direct sequence ultra wideband (DS-UWB) communication systems over multipath fading channels. The first system is the classic DS-UWB system and the second is obtained by adding a forward error control code (FEC), convolutional code. For the two systems, bipolar pulse amplitude modulation (BPAM) is applied. In the receiver end, the selective diversity combining receiver-SRake receiver is used as a feasible receiver. In the proposed coded scheme, we use soft output Viterbi algorithm (SOVA). The analysis shows that the coded DS-UWB system outperforms the conventional DS-UWB system significantly with the increase of the SRake fingers. The effective order of processing gains achieved by the coded scheme is the product of the number of SRake branches and the free distance of the code applied.