n-Connectivity Routing Algorithm Under Border Effects in Heterogeneous Sensor Networks

Wireless sensor networks (WSNs) can be used to monitor the interested region using multihop communication. Coverage is a primary metric to evaluate the capacity of monitoring. Connectivity also needs to be guaranteed so that the sink node receives all sensed data for future processing. In this paper, we study the m-coverage and n-connectivity problem under border effects. We consider the scenario where the heterogeneous sensor nodes are randomly distributed in a circular region. We first exactly derive the network m-coverage ratio that is provided by N sensor nodes by the mathematical formulas. Then, the lower bound of the network n-connectivity probability is also derived. Since sensor nodes are equipped with energy-limited batteries, energy conservation in such networks is of paramount importance to prolong the lifetime of the network. Accordingly, we propose a location-independent, energy-efficient routing algorithm EECCR, which simultaneously preserves the network m-coverage ratio and the sensor n-connectivity probability. Extensive simulation results are provided to demonstrate that our algorithm is correct and effective.