Optimized Techniques Of Wi-Fi-based Indoor Positioning Based On Android Phones' Sensors

Location-based services is essential in people's lives on the present.In an outdoor environment,satellite navigation technology has been widely used in people's lives.But the satellite navigation system is difficult to cover the indoor environment,and the demands for location services are increasingly urgent.With the continuous development of social modernization and the growing number of large buildings,people spend more than 80 percent of the time playing in the indoor environment,so the demand for indoor location services are increasing more and more important.For example,special population's care,fire rescue,large venues management,networking,and other areas of personal location services will require the use of precise indoor location information.In a word,indoor positioning technology has become one of the hot research directions.Existing indoor positioning technology is still an insufficient problem in accuracy of positioning,so we need further research to improve indoor positioning's accuracy.In order to improve the deficiencies of the prior Wi-Fi positioning technology,this paper has proposed an optimization method of Wi-Fi indoor location.The method is based on Android phone sensor,and the principle is combined mobile phones'inertial sensors' trajectory calculation method with Wi-Fi positioning method.It can give peoples' more accurate positions.The manly Android smart phone sensor this paper used is the acceleration sensor,the direction sensor and the gyroscope,and three-axis acceleration data is obtained by using the acceleration sensor,the direction angle data is obtained by using the direction sensor,the rotational angular velocity data is obtained by using the gyroscope,and we use these data to pitch detector and direction,and assess peoples' step dynamic,and then achieve the estimates of peoples'walking track.Finally we will use particle filtering method to integrate walking track data and Wi-Fi positioning data to get the final position of the user.This article is designed and implemented indoor location system based on this suggested method,which can achieve continuous positioning.We import maps to realize this system,and then we compare this method with traditional Wi-Fi based positioning system.The results showed that compared to the traditional Wi-Fi indoor positioning methods,the proposed method can effectively reduce the position error,thereby the method has improved the Wi-Fi-based indoor positioning accuracy.