On the Information Carried by Correlated Collaborative Ranging Measurements for Hybrid Positioning

Previous research contributions have addressed the definition of a Cramer Rao Lower Bound (CRLB) to investigate the performance of hybrid positioning algorithms that exploit satellite-based range measurements and independent terrestrial range measurements. Starting from such results, this work investigates the quantity of information carried by terrestrial relative measurements obtained from the combination of satellite-based range measurements shared among pairs of connected agents. The study is conceived to investigate the impact of such relative ranges on the positioning error when they are used as additional measurements to help improving accuracy and precision of positioning. By considering some prior knowledge about satellite-to-user and user-to-user ranging uncertainties, the approximation of a theoretical limit for this novel class of hybrid positioning algorithms allows to observe when the use of cooperative ranges is beneficial, depending on their variance and on the geometry of satellites and terrestrial agents.