Energy Aware Basestation Placement in Solar Powered Sensor Networks

Sensor nodes are often used in outdoor locations where they can be operated using solar power. When such a network is deployed, there are usually restrictions in the way that the nodes can be positioned, and this results in a node-dependent attenuation of the usable solar energy. This effect must be taken into account when placing the basestations used to communicate with the sensor nodes. In this paper we consider the minimum-cost placement of data collecting basestation nodes so that outage-free operation of the sensor nodes is obtained. This is done by minimizing the number of basestations required when taking into account the energy costs of sensor node traffic relaying. An optimization is first formulated which gives a lower bound on the number of basestations that are required. Because of the complexity of the problem, an algorithm is proposed which can be used to do placements for practical problem sizes. The algorithm uses the result from an iterated local search as a starting point, and then uses an energy aware local optimization to obtain feasible basestation placements. Results are presented which show that the algorithm performs well for a variety of network scenarios.