Evaluating Viterbi decoded Reed-Solomon block codes on a Complex Spreaded DS/SSMA CDMA system. Part II: channel model, evaluation platform and results

Abstract

For pt.I see ibid., p.329-34. In recent years, the Viterbi algorithm (VA) has been shown to be an efficient trellis decoder for binary and non-binary linear blocks. In our simulation study, the performance of VA decoded non-binary Reed-Solomon (RS) block codes, employed in a wideband code division multiple access (CDMA) system, operating in multipath fading channel conditions, was considered. A RAKE receiver-based direct sequence spread spectrum multiple access (DS/SSMA) quadrature phase shift keying (QPSK) system is employed. It uses complex spreading sequence (CSS), such as Frank-Zadoff-Chu (FZC), double sideband (DSB) constant envelope linearly interpolated root-of-unity (CE-LI-RU) filtered general chirp-like (GCL), analytical bandlimited complex (ABC) and quadriphase (QPH) sequences. The paper first describes a novel complex multipath fading channel simulator model. Next, the realistic multiuser multipath fading performance evaluation platform is described. Lastly, simulated bit error rate (BER) performances are presented for uncoded systems and systems employing VA decoded non-binary RS block codes under realistic multipath fading channel conditions. The effects of multiuser interference (MUI) and of channel state information (CSI) on the decoding performance of the VA are also considered