Improved Trilateration Algorithm Based on Unscented Kalman Filter

In order to solve the problem of decreased positioning accuracy caused by ranging errors in indoor or occluded situations, this paper uses the TOF algorithm based on UWB positioning system to achieve ranging, and proposes an improved trilateration positioning algorithm based on weighted centroids to solve the positioning coordinates: using three circles intersect to calculate the weighted center of mass of the intersection point. When the three circles cannot intersect, the radius is enlarged proportionally. The Local Outlier Factor is used to eliminate the abnormal points and then the positioning result is calculated; the Unscented Kalman Filter is used to further improve the accuracy of the positioning results, and at the same time Achieve smoothing of the trajectory. Experimental results show that the overall positioning accuracy of the algorithm proposed in this paper is improved by 15.98% compared with the algorithm without outlier detection and the unscented Kalman filter.