Research On Key Technologies Of Indoor Positioning Based On Ultra-Wideband

With the growing of GPS,beidou and other outdoor positioning technologies in China,outdoor positioning technology has been widely used in commerce.Compared with a large number of commercial outdoor positioning technology,indoor positioning technology is still in the laboratory research stage in China.In recent years,with the gradual development of urbanization and the large-scale reduction of the urban-rural junction,the commercial value of indoor positioning technology in the city is also increasing.It is not only the personnel positioning equipment inside the large shopping mall,but also the intelligent equipment in the household intelligent electrical appliances network.In addition,in the city's very complex environment,the use of indoor positioning technology to complete the positioning of personnel or items can be very good to assist the city's security and fire protection.In terms of indoor positioning technology,based on the large-scale construction of WSN and WLAN,the dominant position of UWB technology is increasingly prominent.Therefore,using UWB technology to achieve indoor positioning has become the best way.Based on the hybrid TW-TOA /TDOA localization method in UWB localization method,this paper improves the model and parameter extraction.The specific improvements are as follows: on the one hand,aiming at the positioning accuracy problem caused by clock stability,an improved node ranging scheme is proposed to improve the positioning accuracy;On the other hand,using the improved model mentioned above,an innovative method of parameter extraction from listening node is proposed.This method not only reduces the extraction of nodes,but also reduces the industrial cost of the whole system.Among them,the advantage of the listening node extraction method is for the hybrid TW-TOA /TDOA positioning method.The time parameters of the hybrid TW-TOA /TDOA positioning method need to be extracted from the communication master node,the target node and the listening node respectively,while the former only needs to extract the time parameters from the listening node.In addition,under the condition of model transformation and positioning effect not being affected,the improvement strategy of time cost is also proposed.In view of the fact that the target number is not single in the actual experiment,this paper USES changing the data packet sent by the communication master node to reduce the time cost.Although changing data packets in the model-based method can be applied to the method of listening nodes to extract data,it is not as effective as the former in terms of time cost.On the basis of theoretical analysis,relevant experiments were carried out to verify some indoor RTLS environments.The fixed number of reference nodes,horizontal comparison of the target node position coordinates,and a certain positioning accuracy comparison.The experiment mainly explains and discusses the influence factors of node distance in several methods.Finally,the advantages and disadvantages of the method and its practical application in engineering are summarized.