Weighted Aggregation Scheme with Lifetime-Accuracy Tradeoff in Wireless Sensor Network

We consider design of wireless sensor network for event detection application. An MMSE based q-bit weighted aggregation scheme (q-WAS) is proposed in which each node transmits q bits to its parent in every session. The observation of each sensor is assumed to be one bit. The simulation results show that 1-WAS achieves better accuracy than a previously proposed one bit aggregation scheme while offering almost same lifetime. With increasing q, the accuracy of q-WAS approaches that of the infinite precision aggregation scheme. Moreover, the lifetime for q-WAS is significantly higher than infinite precision aggregation scheme. For a 100 node sensor network, the simulation results show that 3-WAS achieves a near optimum accuracy. The lifetime of the q-WAS is approximately 1/q-th of the lifetime of the one bit aggregation schemes. Hence this class of aggregation schemes offers a trade-off between accuracy and lifetime.