Clustered Multiuser Detection Using SC-FDE Transmission with Iterative Receivers

Iterative block decision feedback equalization (IB-DFE) algorithms are proven to be powerful tools when detecting several uplink signals sharing the same physical channel. However, those algorithms may face some constraints -- the IB-DFE has some difficulty picking certain signals up if they are considerably weaker than the rest and the computational effort grows exponentially with the number of signals to be detected. In this paper we present a clustered multiuser detection scheme, based on an IB-DFE algorithm. It is demonstrated that if the mobile terminals (MTs) have enough power and are distributed in clusters, with considerable power difference between them, it is possible to successfully detect them all while containing the computational complexity. Our scheme also requires fewer receiving antennas than the original IB-DFE implementations and, with the aid of low-density parity- check (LDPC) and turbo- equalization, it is able to reach high performance levels with low power requirements.