Research On Location Aided WWSN Routing Algorithm In Large Fire Environment

Wearable wireless sensor network(WWSN)is a kind of self-organized cognitive network.It doesn't rely on or rarely depends on infrastructure,but can adjust data transmission strategy intelligently and dynamically according to the change of environment.At present,it is more active in the field of life and medical care,and gradually moves forward to the field of disaster relief and war.Aiming at large-scale fire rescue environment,this thesis puts forward the design goal of routing algorithm and analyzes the current mainstream algorithms,and finds that the current algorithms are not fully suitable for WWSN in fire scene.Therefore,in order to improve the data transmission ability of WWSN in large-scale fire environment,this thesis develops a Mobile Adaptive Routing Algorithm(MARA)which mainly includes two parts: routing discovery algorithm-LAR for Multiple Request Zone(LAR-MRZ)and routing maintenance algorithm-(Route Maintenance Algorithm based on Trust Value)RMA-TV: Firstly,this thesis analyzes the advantages and disadvantages of LAR algorithm in the process of route discovery,and makes a route discovery algorithm-LAR-MRZ with the aid of LAR auxiliary algorithm.Due to the inaccuracy of the expected domain range,the unreasonable setting of the request domain,and the unsolved problem in the discovery process of LAR,this thesis proposes an appropriate routing strategy for these three problems.First,the expected domain is normalized,and the positioning error is considered based on the original algorithm.Then,multiple request domains are designed to adapt to route discovery at different distances.In the end,two solutions are proposed to solve the problem of void caused by narrow request domain.Secondly,in order to increase the reliability of the network,RMA-TV is developed.The link stability and node stability are calculated according to the motion state of the neighboring nodes.Then,according to the link stability and node stability,the trust value between the two nodes is calculated.The trust value can well reflect the changes of the environment between the nodes.The path is preprocessed according to the change of trust value,so that the link is always in trust state.In case of disconnection,the path repair is carried out in the way of reverse maintenance.The simulation results show that the proposed algorithm has excellent performance in both delivery rate and delay,which verifies that the algorithm has good adaptability in WWSN in fire scenarios.