Research And Realization Of The Indoor Positioning System Based On The UWB Range Sensor

With the development of science and technology, the research of target locationhas received more and more attention. In the open air, GPS positioning technologyhas been very mature. But in a complex indoor environment, such as the airport hall,exhibition halls, warehouses, supermarkets, libraries, and underground parking lotenvironment, where we need to identify the mobile terminal or its holders, facilitiesand items in the indoor location information, GPS technology has great limitations. Innumerous personnel detection and location technology, positioning technology basedon UWB range sensor was specifically developed for indoor crowded environment,compared with other indoor positioning technology, it has a series of advantages, suchas strong penetrating power, low power consumption, low system complexity, provideaccurate positioning, etc.In positioning algorithms based on range measurement, the trilateral centroidlocalization algorithm is a classic positioning algorithm, but the positioning accuracyin the triangle border of this algorithm is low. The overall positioning accuracy of thisalgorithm and the causes of positioning error are analyzed and simulated in Matlab.Based on the above analysis, this paper puts forward the inscribed circle averagealgorithm: On the premise of the trilateral localization algorithm, the public inscribedcircle of the three positioning circle in the public area was calculated. In practice, thepublic inscribed circle may not exist, so in this new algorithm, we selected a referencepoint, based on the point near the public area, looking for three inscribed circles ofeach positioning circle, taking the average of three inscribed circles as an estimate ofthe mobile node. Simulation and experimental results show that the inscribed circleaverage algorithm can improve the precision of node location effectively comparedwith trilateration centroid algorithm.According to characteristics of the UWB range sensor, the processing method ofdata from range sensors is proposed. The program of network communicationinterface was written, which can control range sensors, and receive data from rangesensors. In order to achieve visualization of the positioning system’s output, thegraphics programming technology was used. On the basis of all mentioned above, thesoftware platform provided experimental analysis for the inscribed circle averagealgorithm.Trilateral centroid localization algorithm and the inscribed circle average algorithm were integrated into the software platform. With UWB range sensors, apositioning system was set up. Based on this system, accuracy tests of the newalgorithm was done, And the results show that the new positioning algorithmsignificantly improves the positioning accuracy of mobile objects.Finally, based on the two modes of UWB range sensor: MRM (Monostatic RadarModule Reconfiguration) and RCM (Ranging and Communications Module),experiments of ranging and positioning were done with indoor positioning systems,which can provide useful sample data and lay a solid foundation for the furtherresearch.