A New Cooperative Transmission Metric in Wireless Sensor Networks to Minimize Energy Consumption per Unit Transmit Distance

In this letter, we propose a new metric for energy-efficient cooperative transmission in wireless sensor networks (WSN) where the circuit energy consumption is taken into consideration. Under the guide of the new metric, we optimize the energy consumption per unit transmit distance by selecting the appropriate number of cooperative nodes and the transmit energy consumption. In this way, we provide a new point of view to achieve the energy- efficient cooperative transmission, and the proposed metric can be applied in clustered multi- hop sensor networks to transmit data to an appropriate next relay cluster far away from the former cluster.