A Low Complexity Two Stage MMSE-Based Receiver for Single-Carrier Frequency-Domain Equalization Transmissions over Frequency-Selective Channels

In this paper, we propose a novel low complexity two-stage minimum mean square error (MMSE)-based receiver for single carrier frequency-domain equalization (SC-FDE) for space-time block coded (STBC) transmissions over frequency selective channels. We demonstrate that the proposed receiver enjoys a remarkably simple decoding scheme. We further show that, by incorporating linear processing techniques, our MMSE-based receiver is able to collect full antenna and multipath diversity gains, while maintaining low complexity, thus, eliminating the need for maximum-likelihood sequence detection (MLSD), which has certainly prohibitive complexity, specially, when the constellation size of the transmitted signals and/or the block length increases. Simulation results demonstrate that our proposed receiver significantly outperforms the conventional SC-MMSE-FDE receiver, while maintaining nearly similar complexity.