Energy-Efficient Coded Routing with Selective Transmission Power for Wireless Sensor Networks

Based on the empirical studies of approximate linear correlation between transmission power and link quality, we propose a multi-power opportunistic routing scheme with network coding for wireless sensor networks. A new routing metric taking energy consumption and link quality into account is defined, and an optimal transmission power and forwarding set selection algorithm is implemented, which is used to establish lowest-cost paths from each node to sink. The algorithm extends Dijkstra's algorithm and has a polynomial-time complexity. Intra-session network coding method is also employed in the routing process where we propose a distributed forwarding control and quota assignment algorithm to minimize the transmissions of coded packets. Moreover, a novel picking strategy of coding coefficients greatly decreases the header overhead of small size of sensor data packets. Extensive experiments on TinyOS-Mote based testbed show that the routing approaches perform up to 85% better on energy efficiency than MORE with a fixed transmission power.