Abstract
In wireless sensor networks, nodes periodically wake up and sleep in order to reduce their energy consumption. One challenge in this scenario is how to coordinate the sender and receiver so that they can wake up and sleep at the same pace to maintain connectivity. In this paper, we present a synchronization method that has very low energy consumption overhead yet high-precision synchronization performance. Different from existing synchronization methods, it does not need to correct the offsets and skews of the clocks of nodes. Instead, our proposed method takes advantage of the fact that the time interval between two transmitted beacons is the same as the time interval between two received beacons, since the propagation and coding delay can be assumed to be similar in these two transmissions. Thus, the receiver and the sender can be synchronized using their individual clocks. Based on this key idea, our synchronization method can overcome the offset and drift issue without modifying the clocks. This paper focuses on the theoretical analysis to evaluate this proposed method. The closed-form expression of the error limits for our method has been obtained. Also, the correctness of the theoretical analysis has been verified by our experimental results.