Energy Optimal Selection of Access Points in Wireless Sensor Networks

In a Wireless Sensor Networks (WSN), there are normally one or several sensor nodes working as Access Points (AP), which are able to provide a relay for other sensors to an external Internet connection. Since WSNs are resource-constrained, the selection of APs is very crucial in economizing power usage. In this paper, we study the optimal selection of APs to maximize the WSN lifetime. This issue is closely related to routing protocols in WSN. We propose a new adaptive multi-path routing protocol to reduce the energy consumption and guarantee QoS requirements with respect to transmission delay. In this paper, we formulate the issues we mentioned above as a non-linear NP-hard optimization problem. Due to the high computation complexity of this problem, we proposed two polynomial-time approximation algorithms to optimally select APs in the WSN that based on the framework in \cite{X09}. Combining with our new adaptive multi-path routing protocol, our preliminary simulation results show that our schemes can save more than $20\%$ energy compared with the existing APs selection schemes with single-path routing protocols.