Superposition-Coded Concurrent Decode-and-Forward Relaying
  In this paper, a superposition-coded concurrent decode-and-forward (DF) relaying protocol is presented. A specific scenario, where the inter-relay channel is sufficiently strong, is considered. Assuming perfect source-relay transmissions, the proposed scheme further improves the diversity performance of previously proposed repetition-coded concurrent DF relaying, in which the advantage of the inter-relay interference is not fully extracted. 
Chao Wang, Yijia Fan, Ioannis Krikidis, John S. Thompson, and H.   Vincent Poor