Indoor Radio-map Building Method And System Implementation

With the rapid development of the times and the rapid development of information technology,people's perception of their own location is rising.At present,GPS,Beidou navigation and other representative of the outdoor positioning technology can basically meet the needs of outdoor positioning,but the indoor positioning,due to the complexity of the indoor environment,its positioning accuracy significantly deteriorated,still can not fully meet the needs of people.Therefore,the study of indoor positioning technology has a very important theoretical significance and application value.Based on the Received Signal Strength Indication(RSSI),the RF fingerprint localization method is a positioning method for establishing position fingerprints by receiving position-related signal strength values.The method is generally divided into two stages: off-line training and online positioning.Because of its simple structure and high positioning accuracy,it is the mainstream of indoor positioning technology.In this method,the construction of the offline phase Radio-map and the selection of the RF fingerprint will have a direct impact on the positioning accuracy of the system,which is the basis of the realization of the RF fingerprint positioning system.In this paper,the construction method and its characteristics of RF fingerprint are studied.On this basis,a set of hardware and software systems for collecting RF fingerprint data and constructing Radio-map are designed and implemented.The main work is as follows:(1)This paper analyzes the characteristics of RSSI and LQI data,and gives the scheme of constructing location fingerprint based on RSSI.The paper introduces the characteristics of RSSI and LQI data,and analyzes the characteristics of RSSI and LQI data.In order to better describe,analyze and compare the characteristics of fingerprints at different locations and the influence on the positioning accuracy,the stability and fingerprint resolution are analyzed theoretically and compared with the traditional RSSI mean fingerprints.The results of field experiments show that the location fingerprints based on mode of RSSI are better than the traditional position fingerprints,and can reduce the influence of environmental changes on fingerprints and improve the accuracy of the online positioning of the system.(2)Based on IRIS hardware node platform and B / S architecture,SSH framework technology is used to design and implement a set of hardware and software systems for building Radio-map.The system is easy to deploy,can RSSI and LQI raw data real-time acquisition,analysis and processing,and generate the corresponding location fingerprint,and then get the indoor positioning required Radio-map.The radio-map data generated by the system can provide support for the research of indoor positioning technology based on RF fingerprint.The RF fingerprint data set can also be used by the relevant personnel.