Differential spatial multiplexing

In this paper, we present a novel differential space-time (DST) architecture which is well suited for high data-rate applications but requires only a low decoding complexity. Multiple transmit antennas are divided into groups and DST encoding is applied individually to each group. Instead of using the optimum joint-group decoding approach, the receiver combines group interference suppression (GIS) and decision-feedback differential detection (DF-DD) to reduce the decoding complexity. By taking advantage of the differential encoding at the transmitter, the GIS filter can be calculated without knowledge of channel state information (CSI). In addition, both the GIS filter computation and the detection scheme are robust against frequency offsets and phase noise.