Indoor Location Algorithm Based On IMU And WIFI

Recently,with the development of science and technology,Location Based Service(LBS)has also developed enormously.At the same time,people who pursue convenient life make it increasingly demanded,especially in the indoor environment,such as supermarket,museum,parking garage,mine,which usually needs to obtain the position information of the user or equipment quickly and accurately.However the indoor environment is complex and changeable,the propagation of the wireless signal tends to be affected by attenuation,multipath interference and the influence of obstacles,which lead to poor positioning accuracy based on WIFI technology.On the other hand,Inertial measurement Unit(IMU)has large accumulated error in indoor autonomous navigation positioning.In view of the single positioning technology failing to get higher indoor positioning accuracy.Around the IMU and WIFI positioning algorithm research,this paper puts forward the combination of indoor positioning system based on the technology of IMU and WIFI,the concrete research content mainly includes the following aspects:The effective method to remove noise and supple losing data of the raw data for WIFI signal is introduced.The method to calculate distance and location based on the WIFI signal is discussed.The algorithm of traditional localization based on mathematical model is studied,and the probability model localization algorithm is put forward.In the part of pedestrian navigation of reckoning positioning,we can get the number of walking step based on the periodic change information of the vertical acceleration,threshold filtering process is adopted to deal with the problem of invalid steps,average method is adopted to the problem of the direction angle,namely by getting the average of angle accumulated form gyroscope and the angle from magnetometer.WIFI technology is adopted to update the position which involves errors during walking steps.Online updating algorithm is put forward aiming at the randomness of step length.In the part of integrated positioning system based on Kalman Filter,this paper puts forward and analyzes different combinations of fixing,an integrated positioning algorithm based on Kalman Filter is choosed,which divides into two situations,namely deep coupling and light coupling,certainly the two methods has improved positioning accuracy.In this paper,the above three studies will be carried out,then improved or new positioning algorithms will be put forward and the rationality and superiority of the conclusion will be proved by the simulation experiment,which will lay a foundation for the future application of algorithms and contribute to the follow-up research.