Research On Mobile Phone Indoor Location Method Integrating Building Map And Multi-Source Sensors

With the continuous emergence of large hospitals,shopping malls,airports,railway stations and other large complex functional building complexes,the demand for indoor positioning and navigation functions is increasing,which makes more industries have an urgent requirement for indoor and outdoor positioning and navigation system services.On the basis of indoor positioning,scholars have explored various indoor positioning technologies for the needs of underground garage car search,rapid medical treatment in hospitals,and rapid positioning of materials in factories.Global Navigation Satellite System(GNSS)is the main outdoor positioning system,using smart phones can be ubiquitous positioning navigation,but the GNSS signal cannot cover the indoor environment so it is not suitable for indoor positioning services,the current cell phone indoor positioning navigation generally need to use Bluetooth,Wi Fi,accelerometer,gyroscope,barometer and other sensors to obtain the user’s location information.Generally,multiple sensors built into smartphones can provide multiple positioning data sources for indoor positioning,but sensor signals are easily affected by the complex indoor spatial environment,resulting in poor universality of single-sensor-based positioning methods.Therefore,with the help of markers,topological relationships,and semantic information in map scenes,indoor positioning error correction and indoor path planning are gradually becoming important auxiliary information.Based on the application potential of the popularity and synergy of multiple sensors built into smartphones,this paper researches and proposes a cell phone indoor positioning method that fuses building maps with multi-source sensors to address the scientific problems of(1)low accuracy of indoor positioning using a single sensor built into the cell phone,(2)insufficient geometric constraint information in building maps,and(3)multi-sensor fusion synergy in multi-scene conditions.Firstly,we construct Map Location Anchors(MLA)on the basis of the building map for the built-in sensor types of cell phones,and then Bluetooth in the smart terminal interacts with the i Beacon signal in the building for initial positioning using the spatial quadrilateral positioning algorithm.Secondly,we use Pedestrian Dead Reckoning(PDR)to obtain Bluetooth,accelerometer,gyroscope,magnetometer,barometer and other sensor data in the real-time positioning process,and match the MLA geometric constraints for pedestrian position calibration.Finally,the MLA is fused with the cell phone’s built-in multi-source sensors to match the positioning for the navigation process in different scenes of the building.The highlight of this paper is the construction of building map location anchor(MLA)based on building maps and also for the built-in sensor types of cell phones,and based on this,we propose a multi-source sensor cooperative localization method for complex scenarios with high indoor localization accuracy.The results of experiments show that the proposed method not only can effectively correct the cumulative error of PDR,but also the indoor pervasive positioning accuracy of cell phone can reach about 0.5m under the walking node constraint,which can fully meet the requirements of positioning and navigation applications in indoor scenes in people’s daily life.