Research On Confident Information Coverage Hole Healing Strategy In Hybrid Wireless Sensor Networks

Wireless sensor networks(WSN)have been widely used in many fields,such as environmental monitoring and forecasting,medical system and health care,industrial monitoring,precision agriculture and so on.As an important index to measure the performance of WSN,coverage reflects and depicts the degree of sensing quality of an area.The failure caused by energy shortage of sensor node itself and a sudden breakdown,physical attacks,abominable target deployment area,and uneven distribution of nodes with random deployment and all of these will cause a reduction in network sensing and communication capabilities,so then lead to the emergence of coverage holes and affect the network quality of service.This paper focuses on the problem of coverage hole healing in a sensing area of interest in hybrid wireless sensor networks(HSN)including static sensors and mobile sensors.With the emergency of coverage holes,it is necessary to design efficient algorithm according to the number,location and size of the detected coverage holes,and then move mobile sensor nodes to heal holes,so as to ensure the coverage quality of the network.The current researches on HSN coverage hole healing are mostly used simplified and idealized disk coverage model and its derivative model,this kind of research did not fully take into account the spatial correlation of sensed environmental variables within the sensing area of interest and not consider to heal holes through collaborative sensing among the neighbor nodes.It also has higher computation cost and energy consumption.It means that this has caused the waste of sensor node resources in a certain extent.In this paper,a new confident information coverage model(short as CIC)is used as the basic node coverage model.According to the location,the number and the size of CIC hole that has detected and considering the characteristics of the node itself as well as the objectives of healing requirements,we design a efficient and feasible centralized and distributed CIC holes healing algorithms based on the CIC model to improve and optimize the coverage quality of HSN network and to prolong the life of HSN networks.We carried out a series of simulation experiments of the two algorithms in this paper.Simulation results have validated that these two solutions can efficiently healing the CIC holes while minimizing the total moving energy consumption of the dispatched mobile nodes,or maximizing the mobile nodes' average remaining energy after movement or minimizing the maximum mobile energy consumption of each dispatched mobile node,which means the two proposed schemes can satisfy the requirements of coverage and prolong the network lifetime.