Energy efficiency of base station cooperation using amplify-and-forward relay protocol

Since 80% of energy is consumed in radio access side, advanced deployment strategies such as amplify-and-forward (AF)relay networks were presented to provide special diversity for future mobile communication systems. In this paper, BS cooperation scheme is proposed using AF relay protocol for relatively smaller cells than conventional networks. Here, performance of the proposed scheme outperforms both direct transmission and relay cooperative protocols in such a way that, it consumes lower transmission energy than AF for both source and relay nodes. Furthermore, impacts of distance dependent path loss and log-normal shadowing on the performance of proposed scheme are examined and compared to the available schemes such as AF relay networks. Finally, advantages of using fixed and optimal power allocation for base station cooperation schemes are examined and compared to AF relay cooperative networks. It was observed that BS cooperation scheme results in almost 67.64% reduction in μjoules/bit, for both uplink and downlink modes at the worst case. Hence, less power will be consumed to combat fast variations in channel conditions such as log-normal shadowing effect.