Research On K-coverage Control Technology In 3D Underwater Wireless Sensor Networks

The coverage rate of the WSNs serves as one of the important indicators in evaluating the quality of network services(Qos). The Underwater Sensor Networks(UWSNs),as an important branch of it’s application, the research on that coverage control method is particularly meaningful to the achievement of a more reasonable distribution of underwater network space resources, a better grasp of information, fulfillment of environment sensation and the improvement of underwater surviving ability of the UWSNs.Much of the current research on the coverage issue of 3D UWSNs never attaches the importance on the the requirement of k-coverage of various areas. This dissertation bears the research goal of the optimized deployment of differentiated k- coverage requirements and bases its foundation on the UWSNs model which consists of the UWSNs which is connected with the buoy via a cable, a buoy and an anchor. The following research works have been fulfilled:1) A remarkably better result with an innovative method, which is mainly about the lower bound value on nodes deployment, has been obtained by the theoretical deduction and simulation researching the lower bound of nodes required by differentiated k-coverage area(the smaller lower bound of the number of sensors with the same covering effects).2) The proposal of an upgraded simulated virtual force algorithm(VFA)-- the k-ERVFA based on differentiated k-coverage requirements. Through simulation, this improved algorithm significantly increase the 3-coverage rate and 2-coverage rate under the same circumstances of the same maximum iterations and nodes number when compared with the improved 3D CLA-EDS algorithm targeting k-coverage, the improved 3D IDCA algorithm and the classical VFA algorithm. Meanwhile, the 1-coverage of its requirement area only sacrifices very tiny. This draws to the conclusion that the algorithm has attained a better result of differentiated k- coverage requirements with its effect on high k-coverage being obvious.3) The accuracy, validity and universality of k-ERVFA algorithm have been verified by theoretical reasoning that extends the k value to general status which leads to a synchronizing result between the k-ERVFA algorithm and simulation. The cost control of deployment method described in part 1 has been assured through in-depth analysis and sensitivity discussion regarding the effects those simulation parameters such as r、△lmax and Nmax have on the execution of the algorithm. It also obtains some certain conclusions on the choice of these parameters. Moreover, it guarantees the sensor deployment density redundant parameters known as θ(k, ?) could only be valued in a small constant range.4) This dissertation takes into account, at the same time, the improvement and extension of k-ERVFA algorithm which is about to be extended to general conditions such like k-coverage time varying demands. Analyses have indicated that k-ERVFA algorithm is prone to extension with a fine nature of robustness and universality.