Barometer Assisted GPS Denied Trilateration Algorithm for Traversing Vertical Three-Dimensional Spaces

GPS denied localization has increasing application for indoor tracking and navigation. However, general literature focus on finding a location solution within the horizontal x-y plane. We propose a GPS-denied localization algorithm that targets better accuracy for a user travelling significant vertical distances compared to level ground. This algorithm works on the basis of taking a height reading from a barometer and reducing the trilateration problem into a two-dimensional problem. With this algorithm, we are able to obtain a three-dimensional solution with less time and comparable accuracy to conventional three-dimensional trilateration. Our simulations and initial hardware testing show that utilizing the barometer’s readings could cut the computation time compared to conventional three-dimensional algorithms as measurement noise increases relative to the range measurements. We intend to apply the results of this study to an algorithm that can optimize node placement in three-dimensional space, all while the user travels through an area and plants new anchors for the localization network.