Multiple‐encoder layered space–time–frequency architecture with QR decomposition and M‐algorithm maximum‐likelihood detection

Abstract

In this paper, to achieve the available spatial, temporal, and frequency diversities, and also to make the system implementation feasible for high-speed orthogonal frequency division multiplexing multiple-input multiple-output multiplexing, a novel layered space-time-frequency (LSTF) transmitter architecture with multiple channel encoders is proposed with each independently coded information sub-stream being threaded in the three-dimensional (3-D) space-time-frequency transmission resource array. The performance of a non-iterative receiver consisting of a maximum-likelihood detector with QR decomposition and M-algorithm maximum-likelihood detection is exploited, by employing irregular low-density paritycheck code as the channel code. The threaded distribution of each coded information sub-stream in the proposed LSTF architecture makes it achieve the spatial, temporal, and frequency diversities the same as the conventional single-encoder LSTF architecture where coding is applied across the whole information stream, and simulation results show that the performance of the proposed multiple-encoder LSTF architecture is very close to that of the conventional single-encoder LSTF architecture. However, because of the use of multiple parallel encoders/decoders with a shorter codeword length, the proposed LSTF architecture has much lower hardware processing speed and complexity than that of the conventional LSTF architecture.