Research On The Low Redundancy Coverage Algorithm For Medium And High Rate Sensor Networks

Medium and high rate sensor networks includes sensor networks used in industrial real-time control and wireless multimedia sensor networks(WMSNs) wh-ich is new to the sensor networks. Currently there are many key technologies for the medium and high rate sensor networks waiting to be solved, including network architecture and model, group routing protocols, QOS assurance technology, infor-mation security assurance,node deployment and network coverage technology,etc. The network coverage is not only a deployment issue but also a service quality issue. Many sensing models and coverage algorithms designed for traditional sensor networks are no longer applicable to complex medium and high rate networks. This research concentrates on the coverage problem of directional sensor netwroks which belongs to the medium and high rate sensor networks. The main responsibilities are:(1)Analysing the characteristics of medium and high rate sensor networks, also challenges for coverage and evaluation criteria of coverage algorithm.(2)Building an experimental system for medium and high rate sensor networks, it can verify the validity of the algorithm for medium and high rate sensor networks.(3)Taking into account the network's redundancy, according to the characteris-tics of directional sensor node, this thesis designs a directional and adjustable model, and on this basis proposes a low-redundancy coverage-enhancing algorithm based on virtual force. Through the establishment of relation model between virtual force and adjustment value of angle, it changes nodes'sensing direction according to the model;after the node is stable, we determine whether this node is a redundant node by its coverage subsets until the entire network goes into steady state. At the same time, the network adjustment is completed. The simulate results show that this algorithm can effectively solve network's redundancy.(4) Taking into account the network's redundancy, with the already established directional sensing model, a target-oriented connective coverage algorithm of directional sensor network is proposed. This algorithm makes the preliminary schedule to nodes which are randomly deployed by establishing candidate node sets which coverage most target-nodes within deploying circle. On this basis, the algorithm find the node set which can detect all the targets and have the best location and least number by integer linear programming model. Simulation results show that the algorithm not only can reduce the network's deployment costs, but also ensure the network's connectivity under the premise of meeting coverage.