Data Aggregation Scheduling in Uncoordinated Duty-Cycled Wireless Sensor Networks under Protocol Interference Model

Data aggregation is a critical and widely-used operation in wireless sensor networks (WSNs). Data aggregation scheduling (DAS) aims to find an interference-free scheduling for data aggregation with the minimum latency. Most existing algorithms for the DAS problem, unfortunately, assume that nodes are always active, and hence are not suitable for dutycycled scenarios. In this paper, we investigate the DAS problem in uncoordinated duty-cycledWSNs (DAS-UDC problem) under protocol interference model and prove its NP-hardness. To solve this problem, we propose two novel approximation algorithms called SDAS and CDAS with the data aggregation latency of at most O(Rs + ∆) and O(R + ∆) respectively, where Rs, ∆ and R are the maximum depth of the breadthfirst-search tree rooted at the sink node s, the maximum node degree and the graph-theoretic radius of the network respectively. We conduct extensive simulations to evaluate the performance of our algorithms and report their average performance.