Space-Time Pre-Filtering Based Soft-Input Soft-Output Detectors in Frequency-Selective MIMO Channels

This paper investigates low-complexity soft-input soft-output (SISO) detectors for multiple-input multiple-output (MIMO) transmission over frequency-selective channels. The detectors are developed with a unified detection procedure, that is space-time pre-filtering followed by a reduced dimension MAP detection. The condition of perfect pre-filtering is discussed and several suboptimal pre-filtering methods are proposed. Simulation results show that the proposed SISO detectors can make a good trade-off between performance and computational complexity in frequency-selective fading MIMO channels with various spatial correlating factor and Ricean components.