An Autonomous And Portable Indoor Positioning System For Pedestrians

Positioning and navigation are playing an increasingly important role in modern life.Travelling,military,rescue areas are increasingly inseparable from the location-based services.Outdoor positioning depends on GNSS(Global Navigation Satellite System),which have reached a meter-level accuracy.Outdoor positioning also provided a strong support for all kinds of occupations.However,in enclosed indoor environment GPS satellite signals are very weak,other ways should be considered.In these days,portable smart devices have been more and more popular.Smart phones and tablets have already become common devices,which provided indoor positioning with a good environment.The algorithm of fully autonomous pedestrian indoor positioning in this article is based on tablets or smart phones.It uses gait analysis and simplified orientation estimation methods to solve poor performance of sensors in those relatively cheap devices.To do on scene experiment and get an ideal result,a conventional test program is developed.This paper focuses on the following parts:1.Raised a cadence detection algorithm based on dynamic threshold window,which performs better than common algorithm;2.Realized orientation estimation algorithm from gyroscope with the help of accelerometer and magnetometer,and presented heuristic yaw compensation method;3.Wrote a windows8 app store application in.net4.5 framework,as well as doing some comparison between method based on other theories and methods.4.Proposed a method of matching direction between map and heading.