New design of single-symbol decodable STBCs for MIMO communication system

Single-symbol maximum-likelihood （ML） decodable space-time block codes （SSDCs） can achieve a maximal symbol rate of 6/7 for multiple-input multiple-output （MIMO） communication system with five or six transmit antennas by using rate-efficient generalized coordinate interleaved orthogonal designs （RE-GCIODs）. Unfortunately, there are many zero entries in the eodeword matrix of RE-GCIODs. The zero entries result in high peak-to-average power ratio （PAPR） and also impose a severe constraint on hardware implementation. In this paper, for MIMO communication systems with five or six transmit antennas and one receive antenna, a new SSDC is proposed. By combining Alamouti code and orthogonal space-time block code （OSTBC）, desirable properties like RE-GCIODs can be achieved and are derived, including maximal symbol rate up to 6/7, full diversity and single-symbol ML decodability. Moreover, by reducing the number of zero entries in the codeword matrix, the peak-to-average power ratio （PAPR） of our proposed code is lower than RE-GCIODs. Simulation results show that the proposed codes outperform RE-GCIODs under peak power constraint while performing almost same under average power constraint.