Research On Coverage And Connectivvity In Wireless Ad Hoc Sensor Networks

As a new network technology, the sensor networks can be applied to various application areas and have attracted a lot of research interest from research and industry. Coverage and connectivity are two fundamental problems in the sensor networks, which have direct effect on the network performance and answer the questions about the quality of service that can be provided by a particular sensor network.As to the connectivity and coverage problem of randomly deployed sensor networks, we firstly propose a new network model, and then derive the fundamental relationships among cells number, nodes number and the probability of coverage and connectivity through mathematic analysis. The analysis is based on the basic characters of sensor networks and can be extended to analyze other practical sensor networks.As to the fault tolerance of sensor networks using deterministic deployment, we firstly propose a network model based on triangular topology, and secondly, derive the relationships between the probability of coverage and that of the node failure, and then derive the lower bounds on the connectivity probability for triangular networks using the k-subnet concept when the probability of node failure and the network size are given. These results answer the question how we can guarantee the probability of coverage and connectivity by determining the probability of node failure. The comparison between triangular topology and grid topology shows the advantage of triangular topology in the fault tolerance of connectivity.Finally, we propose an algorithm of connected coverage for multiple target points. This algorithm has the O(n) running time complexity and its result is proved closed to the optimal result.