Ph.D. Proposal

Mark Hartigan

(Advisor: Prof. Glenn Lightsey)

Performance of Lunar Radiometric Navigation Satellite Systems

Thursday, May 1 

9:00 a.m.

Montgomery Knight Building 317

Abstract

Global interest is increasing to establish a sustainable human presence on the moon through flight missions, multilateral cooperation, and infrastructure development. To aid these objectives, several organizations – including NASA, ESA, and JAXA – are planning to construct lunar navigation satellite systems (LNSSs) in the coming decade to provide position, navigation, timing, and communication services for users operating on and above the lunar surface. LNSS constellations would enable surface and orbital users to obtain their absolute position, velocity, and time synchronization solely through one-way radiometric observations of range and range-rate made using a radio receiver.

Crucial to the design and implementation of an LNSS is characterizing the achievable performance for end users on or above the lunar surface. Terrestrial Global Navigation Satellite Systems from which proposed LNSS designs are derived benefit from several decades of research, testing, and use. However, changing domains to cislunar space requires novel methods of error characterization and validation before committing to the costly endeavor of placing a constellation of satellites in lunar orbit. Existing research has begun exploring the navigation implications of LNSSs in cislunar space, but without considering the whole trade space of measurement error sources and their implications for end users. This thesis proposes a methodology for evaluating LNSS design choices through state-dependent analytic modeling of the end user measurement error budget, and further use of these models within user navigation filters to yield performance improvements over traditional methods.

The proposed work includes error budget model development and implementation thereof for the real-time navigation simulation of a lander during powered descent to the lunar south pole. Aspects of the proposed models will be verified through hardware testing to validate their use for LNSS design and eventual implementation.

Committee

• Prof. Glenn Lightsey – School of Aerospace Engineering (advisor)
• Prof. John Christian – School of Aerospace Engineering
• Prof. Brian Gunter – School of Aerospace Engineering