Coverage Equalization And Optimization In Stochastic Heterogeneous Sensor Networks

The function of wireless sensor network is to monitor and transmit the data of the target scene in detail.Most of its working places are in the outdoor harsh environment.The special environment makes random deployment more widely used in wireless sensor networks,but random deployment will cause low initial coverage efficiency,and then lead to channel conflict,high energy consumption and other issues.To solve these problems,the focus of wireless sensor network coverage research is to optimize the coverage quality and integrity of the network by changing the node's location or sensing range and other attributes.In order to adapt to the complex and harsh working environment and meet the diverse application of network,ubiquitous heterogeneous network is usually used to contain the error of node's hardware specifications.This paper also considers the "The fracture of communication" between heterogeneous nodes,and all works are compatible with the homogeneous network in conventional research.To solve the problem of area coverage and optimization in multi-level heterogeneous wireless sensor networks,this paper designs three algorithms from three aspects: making the network topology more uniform,detecting and repairing holes and reducing network's redundancy.(1)Aiming at the uneven distribution and the fracture of communication caused by the random deployment of heterogeneous sensor nodes,an algorithm based on “Multi-Distance &Density” Dual-Drived Deployment Optimization for Heterogeneous Sensor Network(DDDH)is proposed.Starting from the problem of "two-way no communication" between heterogeneous nodes,the best deployment state of heterogeneous nodes is determined by using the two-way communication neighbors established by heterogeneous characteristics;the traditional concept of density is improved so that nodes can obtain redundant information of their two-hop neighbors in turn and perform mobile force analysis;The step of the designed node is excited by its redundancy,which effectively guides the node to overcome the problem of local optimization.(2)Aiming at the problem of random holes and redundancy balance caused by heterogeneous sensor network deployment,a Coverage Optimization Strategy of Heterogeneous Sensor Network guided by Hollow Arc(CHHA)is proposed.The sensor only uses its neighbor information as the support to divide the covering circle,analyzes the disassembled arc segments one by one,so as to evaluate the adjacent holes and outline them in series.Based on the information of arc segment within the visual range,the node completes its own redundancy judgment and adaptation assessment of repair,and then selects the incremental self-healing or recruitment repair strategy to compensate for the hollow arc.Compared with the conventional method,the proposed method does the research on the segmentation of void recognition and repair.(3)Radius Adjustment strategy for static Heterogeneous sensor networks with Priority constraints(RAHP)follows the concept of "k-covering intersection" of CHHA algorithm,for reducing the redundant coverage of nodes in the network.The node obtains and analyzes the1-coverage intersection set through the limited hop neighbor's information,then the best sensing radius can be calculated without reducing the network coverage.In addition,two sleeping methods based on distance and arc segment are proposed to reduce the redundant rate with slight coverage loss.The current topology's information of nodes can quantify the order of node's execution,which can help improve the efficiency of the algorithm.