Study of ultra-high frequency indoor positioning system accuracy and methods of its increasing
Indoor positioning systems have a wide range of applications in robotic industrial and logistics facilities, augmented reality devices, sports, services and entertainment. Despite the great demand for such systems, the problem of high-precision positioning indoors is still not solved. Existing methods based on reference markers, dead reckoning, radio navigation and their combinations do not achieve the required characteristics in terms of positioning accuracy and efficiency. This fact determines the relevance of the purpose of this work: the study of positioning accuracy based on rangefinder microwave systems, as well as identifying ways to improve it. The paper analyzes the errors of ranging systems, investigates the influence of calibration of distance measurement channels, the topology of the location of reference points and the use of signal filtering to improve the accuracy of positioning. The paper found that the proposed set of methods for improving the accuracy of positioning makes it possible to achieve root-mean-square errors of less than 3.5 cm while maintaining a short signal processing time. Achieving such indicators requires the use of calibration procedures, monitoring the operation of distance measurement channels, as well as the use of Kalman filters. The main purpose of monitoring the operation of channels is the need to prevent the influence of interference and multipath propagation of signals on the evaluation results. In addition, reaching the high point requires the correct selection of reference beacon locations used in position estimation. It has been established that the smallest error is achieved when the object is located inside the triangle formed by triples of reference beacons. The obtained characteristics are sufficient to develop a reliable internal positioning system, which can be used in the organization of automatic operation of industrial, logistics and household robotic systems, orientation and navigation tools in large public places of commercial, cultural and leisure purposes, as well as for tracking movements and movement parameters. people in the systems of medical and sports and health purposes.