Synchronization of Multiple Levels of Data Fusion in Wireless Sensor Networks

In wireless sensor networks, in-network data fusion is needed for energy-efficient information flow from a plurality of sensors to a central server or sink. As data (either raw or fused) is propagated towards the sink, multiple levels of data fusion are likely. The data fusion at various levels should be synchronized in order to fuse data effectively. It is important that information from as many sensors as possible to be fused in order to increase the credibility of the aggregated report. However, there are trade-offs between fusing a large number of sensor reports and the latency incurred in the aggregation process. The paths taken by the data towards the sink determine where data can be fused, and thus, have an effect on the efficiency of the aggregation process. In this work, we propose a methodology by which the various levels of fusion are synchronized to ensure that the aggregated report has a desired trade-off between credibility and latency, regardless of the topology of the structure created by the integration of the paths on which data traverses towards the sink.