Delay-tolerant space-time block codes for asynchronous cooperative relaying

In cooperative networks using a decode-and-forward strategy, the multiple relays effectively transmit a distributed space-time code, the performance of which can be severely degraded when timing synchronization among the relays is not assured. Recent work by Xia et al. and Hammons et al. have investigated the design of distributed space-time codes that are delay tolerant, in the sense that full spatial diversity is achieved regardless of relative timing offsets. In this paper, new distributed space-time codes are introduced that are fully delay tolerant.