A hybrid localization algorithm using Inertial Sensor, Satellite and Wi-Fi for Smartphone

The complex environment based on Intelligent mobile phone navigation technology has become a research hotspot. The traditional combination navigation technology based on satellite and inertial navigation system can effectively compensate for the effect of short satellite signal loss, but the sensors used in strapdown inertial navigation system generally need high precision and sensitivity, and the existing smart phone built-in MEMS sensor has relatively low precision and sensitivity. One the other hand, the smart phone’s WiFi signal can be considered for improving the positioning performance of inertial navigation system in the absence of satellite, but the fingerprint matching Iocalization results are scattered and there is noise because of its non-Gaussian noise and multipath interference in the outdoor scene. In order to improve the positioning and navigation accuracy and robustness of the smart phone in complex environment, a WiFi-aided fusion positioning algorithm for satellite and inertial navigation system is proposed, which includes two stages, namely, navigational solution and optimization fusion. In order to improve the positioning accuracy, in the navigation solution phase, in the absence of satellite, the system outputs the location result of the outdoor WiFi location algorithm and the combined navigation location result to the optimized fusion device. In order to improve the robustness of the positioning, in the optimization fusion stage, the paper makes a second fusion of two positioning results through an improved fusion weighted average mechanism. The experimental results show that the positioning accuracy of the satellite can be improved obviously in the time of the effective time and the failure moment after WiFi calibration.