Two-stage blind adaptive multiuser detection algorithm for DS-CDMA UWB in ISI channels

Ultra wide-band (UWB) communication has to face two problems of multi-access interference (MAI) under multiple access scenario and intersymbol interference (ISI) in multipath environment. In this paper, we proposed a blind adaptive multiuser detection algorithm for direct-sequence code division multiple access (DS-CDMA) UWB systems in ISI channel, called two-stage algorithm, which consists of two stages. The first one jointly suppresses MAI and equalizes ISI to estimate multipath components of received symbol based on constrained minimum output energy (CMOE) criterion. The second combines these multipath components adaptively to achieve multipath diversity. Simulation results demonstrate that the proposed algorithm can effectively suppress MAI and equalize the ISI at the same time.