An indoor positioning algorithm based on Wi-Fi fingerprint and inertial navigation system

Large buildings grow rapidly nowadays, indoor positioning technology is becoming increasingly important. Satellite navigation system, though very mature in the outdoors, loses the ability to locate indoors due to the block by the buildings. The combination of widely covered Wi-Fi signals and independent inertial navigation system is proposed to solve the indoor positioning. In order to improve the accuracy of indoor positioning, an indoor positioning method based on Wi-Fi fingerprint and inertial navigation technique is proposed in this paper. The motion state and the position information are obtained by an inertial sensor including a gyroscope, an acceleration sensor and a magnetometer, the dynamic adjustment threshold algorithm is proposed to determine the walking attitude of pedestrians, the walking direction is obtained by using the direction detection algorithm, the particle filter algorithm with improved map matching is used to calculate the pedestrian position, and the inertial sensor navigation information combined with Wi-Fi fingerprint location information is used to correct the position of pedestrians and reduce the position error. Simulation experiments were carried out to verify the effectiveness and practicability of the algorithm on the 4th floor of the new main building of Beihang University.