Comparison of Outage Probability Between Best-relay 2-hop Relaying and 3-hop Relaying

In this paper, we investigate decode-and-forward (DF) relaying systems with a direct link between the source and the destination node. The objective of this paper is to determine the better relaying strategy between 3-hop DF relaying and dual-hop DF relaying with the best relay selection. Assuming Rayleigh fading channels, we present closed-form outage probability of the 3-hop relaying and the dual-hop relaying, respectively, and compare the performances by numerical investigation. Numerical results show that if the channel is poor, the outage performance of the 3-hop relaying is better than the dual-hop relaying.