Overhearing model for efficient operation in energy harvesting wireless sensor networks

An energy harvesting node aims to maximize performance, while balancing the available energy and consumption. As long as the consumption does not outpace the harvested and stored energy, the node can remain operational virtually forever. The component that consumes a significant portion of energy is communication. If the energy spent for communication can be accurately predicted, other aspects of node operation can be made more efficient while keeping the harvesting/spending pace well balanced. However, communication energy is consumed not only for packet transmission and reception, but also overhearing. In this paper, a model to predict the rate of packet overhearing from local traffic information is proposed. The model is based on the X-MAC protocol, a widely used low-power listening mechanism. Simulation experiment verifies that the model can give accurate prediction of packet overhearing rate for nodes operating in a single role.