Performance Evaluation of Hybrid Channel Assignment for Wireless Sensor Networks

Data transmission in Wireless Sensor Networks (WSNs) is physically constrained by interference, throughput, latency and many other physical phenomena. We propose a distributed hybrid algorithm to perform the selection of communication channels in such a way that overall throughput, latency, energy and overhead are improved. A tree structure is built out from the sink, in order to elect sensors with the highest degree of connectivity as parents, and sensors with the lowest degree of connectivity as leaves. A set of parents and leaves are assigned to a single fixed channel. Specific sensors, called mediators, are assigned to several orthogonal channels. So, they can switch dynamically to the static channels of parents for collecting the data. This allows the data to be efficiently propagated in parallel on multiple channels from parent to mediator to parent towards the sink. We compare the results obtained with those for single and multiple channels by taking sink throughput, broadcast latency, energy consumption and routing overhead as performance criteria. We show that our method provides better results.