High-rate full-diversity space-time-frequency codes with PIC decoding

In this paper, a simple design of a linear dispersive space-time-frequency (STF) code is proposed with a design criterion to achieve high rate for frequency-selective channels in terms of multipath when the Partial Interference Cancellation Group (PIC) group decoding is applied at receiver. With an appropriate grouping scheme as well as the PIC group decoding, the proposed STF code is shown to obtain the similar diversity gain as the maximum likelihood (ML) decoding, namely full-dimensional sphere decoding, but have a low decoding complexity. It seems as an intermediate decoding between the ML receiver and zero-forcing (ZF) receiver. The proposed grouping design criterion for the PIC group decoding to achieve full diversity deploying the orthogonal frequency-division multiplexing (OFDM) technique is also an intermediate condition between the loosest ML full rank criterion of codewords and the strongest ZF linear independence condition of the column vectors for the equivalent frequency-selective channel matrix. It can achieves full diversity with the PIC group decoding for any number of sub-carriers and the data rate can be made high. Simulation results show that the proposed STF code can well address the rate-performance-complexity tradeoff of the multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) communication system.