A distributed space-time block coding scheme based on multi-relay selection

Cooperative diversity techniques have been adopted as an efficient way to mitigate multipath fading in wireless environments,and the performance will become more efficient when combining with space-time block coding.The traditional space-time cooperative communication chooses all the relays which could decode correctly,but it can't achieve the additional benefit when cooperative nodes more than the column of space-time matrix.In this paper,the multi-opportunistic relaying(M-OR)strategy was proposed to select multi relays.Then,the cooperative diversity of the distributed space-time block coding(DSTBC)was developed based on M-OR.Under the given STBC coding matrix,many appropriate terminals were selected to participate in the cooperative communication of distributed space-time block coding according to the state of channels.The new scheme can obtain the diversity-multiplexing tradeoff of traditional scheme by simple protocol and save the system energy.Simulation result validates the good performance and availability of the new cooperative scheme.