Research On Magnetic Field Based Indoor Self-location Technology

Abstract–Indoor location technology is a matter of access to obtain location information, which canprovide a variety of services for the user, have broad application prospects both in military andcivilian fields. Traditional method of indoor self-location technology includes ultrasonic positioningtechnology, Bluetooth technology, radio frequency identification technology and wireless sensornetwork technology, each with distinct characteristics. Because of the complexity of indoor locationenvironment, traditional method of location has various defects, requiring a combination of newmethods and techniques.Evidence shows that a large variety of animals use Earth’s magnetic field for navigation.Inspired by this intriguing ability of animals, this thesis proposes an algorithm that utilizes localanomalies of magnetic field to achieve2-D indoor self-location. Monte Carlo Location (MCL) isone of the most popular probabilistic techniques due to the high efficiency and accuracy, but onepotential problem is particle impoverishment.The main contents of this thesis include the following aspects:First, briefly describes the current several indoor location technology principles andcharacteristics, analyzes the advantages and disadvantages of various indoor location technology,and highlights indoor location technology based on magnetic fields.Secondly, introduces the basic concepts and applications of probabilistic methods in indoorlocation, analyzes several typical probabilistic methods including Kalman filtering, Markov gridmethod and topology method, particle filter method. In particular, compared to other methods,Monte Carlo particle filter positioning method can achieve a simpler and more intuitive positioning.Furthermore, the author optimizes existing motion model to achieve a2-D object movementmodel.Finally, in order to further improve the performance of MCL, the author employs a BSASclustering approach to get the clustering information and thus resolving the problem of losingeffective particles. Also, this thesis applies a relevant point method to resolve similar magnetic fieldinterference problem.The proposed method was simulated and tested in a real environment. The results show that theproposed method can provide a simple, reliable, low-cost solution for indoor location.