Pedestrian Indoor Navigation Algorithm based on the Pseudolite and Low-cost IMU with Magnetometers Including In-Flight Calibration

Abstract

In the current navigation environments, the most unsolvable subject is an indoor positioning or navigation. Of course, there have been many researches about indoor navigation such as pseudolite, indoor GPS, Wi-Fi, UWB, RFID and so on. However, we don’t have definite or absolute solutions in indoor environments as we use GNSS in outdoors. As mobile environments are constructed in these days, people or robots have locationbased applications in indoor. And the mobile devices such as smart phones and mp3 players contain GPS chipset, low-cost IMU and magnetometers. So we hope to implement indoor navigation module using these multisensors. The object of this paper is to develop and implement cost-effective, accurate and robust indoor navigation technique for pedestrians or robots in mobile environments. The navigation module is constituted with GPS receiver for pseudolite, 3 axis accelerometers, magnetometers and gyroscope. And this navigation algorithm includes positioning, attitude estimation, inflight calibration and magnetic disturbance rejection. The position is calculated using pseudolite measurements and accelerometer measurements with attitude information. The attitude can be estimated using IMU and magnetometer measurements. Using this algorithm, we could estimate position and attitude of pedestrian.