A Joint Look on Lunar Satellite and Cooperative Surface PNT

A large number of missions to the Moon is planned in the coming years by both, public and private sectors. A high demand for a Lunar position, navigation and timing (PNT) system exists to aid landing, to support autonomous robotic exploration etc. ESA has proposed a satellite based system for communication and PNT. Furthermore, cooperative radio navigation for users on the Lunar surface, where PNT is provided through radio signals exchanged among robots and other entities, has been suggested. An analysis of the combination of satellite and cooperative navigation for Lunar PNT has not been done yet. In this paper, we provide a first estimation theoretic analysis of joint Lunar satellite and cooperative surface PNT. We derive the Bayesian Cramér-Rao bound (BCRB) and analyze the benefit of cooperation by comparing different cooperation strategies and scenarios, using system parameters from recent studies.