A DS-UWB Interpath Interference Suppression Scheme Based on MLSE Algorithm

By taking advantage of the good correlation properties of spreading codes, RAKE receiver can resolve multipath components with propagation delay difference larger than one chip period. However, for DS-UWB systems, the good correlation properties are missing due to the use of low processing gains to support high data rates. Hence, the interpath interference (IPI) becomes an important factor to system performance. In this paper, the maximum likelihood sequence estimation (MLSE) is used to combat IPI. MLSE formulations for DS-UWB signals are derived and a reduced complexity RAKE-MLSE structure is proposed. Various simulations are carried out to assess performance of the proposed structure. Results obtained indicate that significant performance gains over conventional RAKE receiver can be achieved