Convolutionally Encoded TH-BPSK UWB System over Multipath Channels

This work pays attention to the performance analysis of the conventional and encoded time hopping binary phase shift keying modulation (TH-BPSK) ultra wideband systems over multipath fading channels. In order to resist the multipath effects, selective diversity combining Rake (SRake) receiver is employed. The encoded TH-BPSK UWB system is obtained by substituting a convolutional encoder for the repetition encoder. Soft output Viterbi algorithm (SOVA) and Viterbi algorithm (VA) are employed as the decoding methods. The performance analysis shows that the coded TH-BPSK system outperforms the uncoded scheme significantly with the increase of the SRake receiver 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 convolutional code.