Border Effect Analysis for Reliability Assurance and Continuous Connectivity of Wireless Sensor Networks in the Presence of Sensor Failures

This paper presents a model of the connectivity of a wireless sensor network (WSN) deployed over a square area, which considers border effects. This model supports an accurate evaluation of the reliability of the network with and without node failures. Using the proposed model we analyze the tradeoff between the number of sensors and their communication range when deploying a wireless network that is connected with high probability and validate this analysis through simulation experiments. Additional simulations, considering sensor failures, ratified that periodic sensor redeployments, calculated according to the proposed model, can extend the reliability of WSNs, keeping them connected with high probability. For applications that can withstand temporary network disconnection, we obtained theoretical and experimental evidence that the proposed model also supports the calculation of a less frequent redeployment procedure that provides network connectivity at high levels of availability. Finally, extending the approach to a circular shaped area was considered.