High-rate irregular-LDPC coded OFDM BLAST systems

This paper is focused on the study of high coding rate irregular low-density parity-check (LDPC) coded Orthogonal Frequency Division Multiplexing (OFDM) Bell Laboratories Layered Space-Time (BLAST) [1] systems for high-speed wireless transmission. One modified LDPC-coded OFDM BLAST scheme is proposed. To generate high coding rate irregular LDPC codes, three construction rules are adopted to obtain low encoding complexity with little loss of decoding performance. The list sphere decoding is adopted for BLAST detection [2]. The simulation results show that with sphere decoding for BLAST detection and LDPC as channel code, this proposed OFDM BLAST scheme can jointly exploit the available spatial, frequency and temporal diversity as effectively as the OFDM-based BLAST applying coding across the whole data stream [3], and reduce the code length and processing rate for LDPC construction and the implementation of LDPC encoder and decoder as much as the OFDM-based BLAST assuming independent coding within each sub-stream [3].