Approach On Personnel Localization And Routing Strategy Of Location Information By Wireless Sensor Networks

In order to improve rescuing efficiency and searching precision as well to reduce second loss during rescue process,it is crucial to rapidly obtain the position of rescuee and rescuer. From the perspective of utility, Wireless Sensor Networks(WSN) is an ideal option for its numerous excellent properties. We establish a WSN-based localization system after summarizing lots of indoor positioning schemes.The system acquires support from nodes deployment method, positioning algorithm and route protocol.So as to make the system practically work, some concrete missions have been done as follows:First of all, the common architectural structures have been sorted into two forms: inner-corridor and large-space zone.An optimized fixing deployment approach is proposed, which gets full-coverage of space, all-connectivity of network.The approach facilitates the position-based service and provides network infrastructure to the algorithm below.Further, a stochastic model is introduced to assess the validity of deployment approach above.Secondly, a coarse-grain and a fine-grain localization algorithm are proposed. The coarse-grain algorithm estimates the proximate range of unknown nodes. Although it is not that accurate, coarse-grain algorithm meets the localization requirement smoothly and implements easily. On the other side, precise coordinate of unknown nodes can be obtained with the help of fine-grain algorithm,which includes range-based algorithm and range-free algorithm.Range-based algorithm is the improved RSSI measurement method,while range-free algorithm is the improved weighted centroid algorithm.The improved RSSI(Received Signal Strength Indication) measurement method need solve equation set,and this process is operated by a swarm intelligent algorithm named as Parallel Pattern Search with Swarm Update (PPSSU).The improved weighted centroid algorithm is refined by an Unscented Kalman Filter (UKF) procedure after distance related centroid coordinate achieved.At last, some routing related problems are studied. A location-aided multipath route protocol is devised It takes use of location information while constructing route and transmits message via multipath. The protocol is proved to be more reliable and efficient than single-path protocol as well as ordinary multipath protocol. During the research process, simulation software Matlab and NS-2are used to analyse localization-accuracy, system-reponse time, packet-delivery delay and route reliability. As a conclusion, the performance of localization system is generally satisfied. It makes the positioning work prompt and accurate.