Adaptation of One-Way Radiometric Range and Range-Rate Errors to the Lunar Environment

Several organizations, including NASA and the European Space Agency, have initiated plans for establishing lunar navigation satellite systems (LNSSs). This effort is driven by surging interest in the Moon as a platform for scientific discovery and staging area for future missions beyond Earth orbit. Near-Earth missions benefit from GNSSs, which have been refined over decades and are capable of real-time, sub-meter level positioning. For GNSS systems, the navigation community and managing organizations, such as the U.S. Department of Defense (in the case of GPS), have precisely characterized the error sources inherent in pseudorange and range-rate measurements in Earth’s vicinity. Here, we draw parallels between errors in current GNSSs and those expected in future cislunar navigation systems. We identify key differences between the terrestrial and lunar environments and propose methods to accurately quantify the resulting measurement errors. Specifically, we develop techniques for constructing a time-varying error budget for pseudorange and pseudorange-rate measurements near the Moon and then test these techniques using arbitrary system and signal configurations.