Cost-aware opportunistic DF relaying with power constraints

This paper proposes a cost-aware opportunistic relaying scheme to minimize total cost in decoding and forwarding (DF) relay networks with power constraints. In the proposed scheme, a relay is selected such that it costs minimally among relays which correctly decode the signal from the source and have sufficient power to transmit the signal to the destination. We derive the outage probability and the average total cost of the proposed relay selection scheme. By means of simulation we show that the numerical results perfectly match our theoretical analysis. Simulations demonstrate that the proposed scheme can effectively reduce total cost compared to the best relay selection scheme. It is also shown that there exists an optimal source power which minimizes the average total cost.