Power efficiency of decode-and-forward cooperative relaying

We investigate fundamental characteristics of cooperative transmission in terms of power efficiency. By introducing the concept of “cooperative region”, we evaluate the average power efficiency which is defined as the ratio of total consumed transmit power with cooperation to that of direct transmission and show how the average performance depends upon the QoS requirement, distance between source and destination and on node density. Further, we propose a dynamic cooperation scheme that combines both cooperative and direct transmission. Analytical results are supplemented by simulation results to demonstrate the energy saving of cooperation transmission.