Iterative Multiuser Detection with Spectral Efficient Protocol for Relay-Assisted SC-FDE

This letter proposes an iterative multiuser detection scheme using spectral efficient protocol for relay-assisted single- carrier frequency-domain equalization (SC-FDE). The proposed system achieves spatial diversity over fading channels in a distributed fashion. In the proposed system, two sources with user-specific interleavers access a relay simultaneously, which increases spectral efficiency of time-division multiple-access (TDMA)-based relay protocol. Interference from the other source is removed by an iterative detection method in the frequency domain at the destination. Simulation results show that the proposed system can obtain diversity gain without sacrificing spectral efficiency and approaches the single-user bound.