Information Fusion Strategies for Collaborative Radio SLAM

Information fusion strategies for navigation using signals of opportunity (SOPs) in a collaborative radio simultaneous and mapping (CoRSLAM) framework are studied. The following problem is considered. Multiple autonomous vehicles (AVs) with access to global navigation satellite system (GNSS) signals are aiding their on-board inertial navigation systems (INSs) with GNSS pseudoranges. While navigating, AV-mounted receivers draw pseudorange measurements on ambient unknown terrestrial SOPs and collaboratively estimate the SOPs' states. After some time, GNSS signals become unavailable, at which point the AVs use the SOPs to aid their INSs in a CoRSLAM framework. Two information fusion strategies are studied: (i) sharing time-of-arrival (TOA) measurements from SOPs and (ii) sharing time-difference-of-arrival (TDOA) measurements taken with reference to an SOP. Experimental results are presented demonstrating unmanned aerial vehicles (UAVs) navigating with the CoRSLAM framework, reducing the final localization error after 30 seconds of GPS unavailability from around 55 m to around 6 m.