We are witnessing a space renaissance. Tens of thousands of broadband low Earth orbit (LEO) satellites are expected to be launched by the end of this decade. These planned megaconstellations of LEO satellites along with existing constellations will shower the Earth with a plethora of signals of opportunity, diverse in frequency and direction. These signals could be exploited for navigation in the inevitable event that global navigation satellite systems (GNSS) signals (e.g., GPS) become unavailable (e.g., in deep urban canyons, under dense foliage, during unintentional interference, and intentional jamming) or untrustworthy (e.g., under malicious spoofing attacks).
This talk will present a framework, termed STAN: simultaneous tracking and navigation, for exploiting signals of opportunity from LEO megaconstellations, which are not intended as navigation sources. In this framework, specialized cognitive radios draw relevant positioning and timing information from unknown downlink signals of LEO satellites with poorly known ephemerides to build and continuously refine a spatiotemporal signal landscape map of the environment within which the radios simultaneously localize themselves in space and time. We will present an end-to-end research approach, spanning theoretical modeling and analysis of signals of opportunity, specialized cognitive software-defined radio (SDR) design, practical navigation algorithm development, and experimental demonstration of our system on ground and aerial vehicles, navigating with multi-constellation LEO satellite signals (Starlink, Orbcomm, and Iridium) to an unprecedented level of accuracy.