Resolving energy hole problem based on unequal cluster size in heterogeneous Wireless Sensor Networks

Energy hole problem is one of the most important hot spots of the academic research in Wireless Sensor Networks. The proposed strategies of clustering focus on heuristically determining the cluster size rather than obtaining the optimal cluster radius for Wireless Sensor Networks and fall short in the application requirement of time-sensitive. To overcome these limitations, in this paper, the strategy of resolving energy hole with unequal cluster radius is proposed on basis of time-sensitive in heterogeneous WSNs. Firstly, we formulate the optimal model of non linear programming problem accorded with the requirements of network lifetime and latency-time in heterogeneous network model. Then, NLP problem is simplified by Lagrange-Newton method in order to prove that there is a feasible solution for the optimal model. In succession, an effective algorithm to obtain the optimal solutions of cluster radius is proposed after analyzing the characteristics of this optimal model theoretically so that it can be good practice guidance for deployment of heterogeneous WSNs. Finally, the simulation results demonstrate the performance advantages of our strategy.