Research On Coverage-all Targets Algorithm For 3D Directional Sensing Model

Wireless Multimedia Sensor Networks is a new sensor network with multimedia information sensing such as audio,video,and images.In WMSN,a large number of sensor nodes are densely deployed in the coverage area.Due to the randomness of the distribution,it may lead to multiple sensor nodes covering a target or target missing and other issues.This will result in a waste of sensor resources and a decline in network performance.Monitor all the targets,that is,with the least number of sensors to cover all the targets,which is Coverage-all targets problem.In order to solve the problem of covering the whole target,this paper studies from the following three aspects:Firstly,since the Coverage-all targets problem belongs to the NP-hard problem,and the swarm intelligent algorithm is the most effective way to solve this.Gravitational search algorithm is one of the most advanced,most representative and optimal evolutionary algorithms in this field.Compared with other swarm intelligence algorithms,the gravitational search algorithm has some advantages in solving the WMSN Coverage-all targets problem.However,in the WMSN network,the number of sensor nodes is very large,which puts forward greater demands on the performance of the core optimization algorithm.In order to improve the performance of gravity search algorithm,differential mutation strategy is introduced on the basis of the evolutionary strategy.Weight function is introduced to balance the global exploration and local search capabilities of the algorithm.The particles are divided into good,medium and poor according to their qualities,and using different types of particles for gravity calculation in different iterative periods for avoiding the local optimum problem.Based on the above improvements,Piecewise gravitational search algorithm of weight function is proposed.Through the simulation experiment,it is proved that the convergence algorithm can reach the theoretical optimal value and the convergence speed is obviously faster than the other improved algorithm.Secondly,coverage-all targets mathematical model of three-dimensional directed perception model is created to improve the practical application of coverage control algorithm for the actual coverage of the wireless multimedia sensor network coverage.The coordinates of each point are defined by analyzing the topological structure of the three-dimensional directed perception model.After the mathematical derivation,the target coverage condition is determined,that is,the target is satisfied within the sensing range of the sensor and the regional perspective,so the coverage-all targets mathematical model is established.Finally,in order to solve the problem of coverage-all targets,Coverage-all Targets Control Algorithm is proposed.Each sensor cooperates with others to cover all the targets by adjusting the elevation angle and deflection angle of each sensor.Adjusting the pitch angle and the deflection angle of the sensor is an optimization problem,therefore,this paper uses Piecewise Gravitational Search Algorithm of weight function as the core algorithm to solve the optimization problem.The experimental results show that the algorithm can cover all the targets with less sensors.