Qualitative Evaluation of Clusters in Wireless Sensor Networks Using Fuzzy Logic

In most applications of wireless sensor networks, it is not possible to charge the nodes' batteries, so the protocols designed for these networks must be as energy-efficient as possible. Clustering is one of the main approaches to designing energy-efficient and scalable protocols for wireless sensor networks. The use of clusters reduces the communication overhead caused by data transmission as well as energy consumption and wave interference between nodes. Despite the importance of clustering in wireless sensor networks, no criteria have yet been proposed to evaluate the quality of clusters derived from clustering algorithms. This paper defines several criteria for evaluating the quality of clusters formed in different clustering protocols. Then, these criteria are combined using fuzzy logic. With the help of the resulting fuzzy criterion, the quality of clusters formed in different clustering algorithms can be better compared. Finally, the correctness and feasibility of this fuzzy evaluation criterion have been verified by simulating three applied protocols and comparing the metrics evaluation results with what is actually happening.