Space-Time Coding with High-Performance Demodulation for Two-Relay DF Cooperation Systems

In this paper, we consider a decode-and-forward (DF) cooperative communication system with half-duplex (HD) nodes consisting of a source node, a destination node, and two relay nodes. We propose a space-time coding scheme and employ two different decoding strategies at the destination. First, we employ an appropriate power profile and a maximumlikelihood (ML) combiner at the destination. Second, we use a cooperative-MRC (C-MRC) combiner at the destination. The numerical results clearly demonstrate that both of the mentioned schemes outperform a recent work while preserving the maximum multiplexing gain of two-third.