Patched Distributed Space-Time Block Codes

In this paper, we propose Patched Distributed Space-Time Block Codes (DSTBC) for the Dynamic Decode and Forward (DDF) Relaying protocol, in which the relay transmits combination of information from the first and second phase of the DDF protocol, and the destination makes a linear combination of symbols received in the two phases. Thus, from the error correcting code point of view, the number of coded bits seeing a diversity-one channel reduces proportionnally as the number of symbols sent by the relay increases, which is not the case with known schemes. In other words, the length of the phase two of the DDF protocol needed to achieve full diversity can be reduced with respect to known schemes. Three examples of Patched-DSTBC are presented, the Patched Alamouti, the Patched Golden Code and the Patched Silver Code whose outage analyses prove the diversity enhancement offered by the proposed scheme.