| With the rapid development of information technology and the popularization of smart phones,the indoor positioning technology based on mobile phones has become a hot research topic.At present,magnetic matching(MM)indoor positioning technology,without any infrastructure,can achieve fast and accurate positioning through matching the fingerprint,which is the magnetic field difference caused by the soft magnetic and hard magnetic.The collected geomagnetic data is closely related to the height and attitude of the phone in environment indoor.Magnetometer calibration can reduce the influence of attitude on the geomagnetic data,but the deviation remains.The influence of height on geomagnetic data was mentioned in some theses,but not in depth.This thesis studied the effect of altitude on the geomagnetic data,taking account of different situations of using mobile phones,such as calling,texting,navigating and putting in pockets,and analyzed the influence of the mobile phone's attitude and height on the collected geomagnetic data.Then this thesis researched and implemented a WiFi-assisted geomagnetic localization system suitable for mobile phone multi-use mode,which was robustness and could accurately locate in different scenarios.The method classified the using pattern of mobile phones according to their height,and recognized the pattern by their attitude,so that established different fingerprint databases according to different patterns,to realize the multi-pattern positioning of mobile phone and improve geomagnetic positioning accuracy.Finally,by combining WiFi positioning technology,using WiFi positioning results to restrict the search scope of magnetic fingerprints,the thesis improved the matching of magnetic fingerprints,and the positioning accuracy of MM.The experimental results showed that the combination positioning system of WiFi assisted geomagnetic improved the average positioning accuracy to 3.6m,and was robust,for all sorts of phone usage patterns. |
PDF Full Text Request