The Multiple Interferometric Ranging Analysis using GPS Ensemble (MIRAGE) computer program processes spacecraft-tracking data to determine orbits of single satellites, or of multiple satellites with intersatellite tracking, to within position errors as small as a few centimeters (see figure). MIRAGE also targets spacecraft maneuvers (changes of velocity) to precision higher than that achievable by current spacecraft hardware. Tracking data that MIRAGE can utilize include Global Positioning System (GPS) pseudorange and phase, data from general range and Doppler measurements, angles, data from optical measurements, and data from very-long-baseline interferometry (VLBI). The modular program structure enables addition of other tracking data types for specific user spacecraft.

MIRAGE implements a variety of geometrical and dynamical models that the user can control. A pseudo-epoch-state filter in MIRAGE smooths over data arcs selectable by the user, yielding robust solutions in the presence of bad tracking data and modeling errors. Operation is simplified through a system of interdependent and automated Unix and Perl scripts or through interactive X-Window menu-driven software wrappers. MIRAGE could be particularly useful for navigating multiple satellites to maintain them in a constellation for global telecommunications.

MIRAGE serves as a navigation system for multiple Earth-orbiting spacecraft. This diagram summarizes its functions.

This program was written by Bobby G. Williams, Peter J. Wolff, Rick F. Sunseri, Theodore R. Drain, James B. Collier, Tseng-Chan Wang, and Joseph R. Guinn of Caltech for NASA's Jet Propulsion Laboratory. NPO-20287

This Brief includes a Technical Support Package (TSP).
Program performs high-precision spacecraft-constellation navigation

(reference NPO20287) is currently available for download from the TSP library.

Don't have an account? Sign up here.

NASA Tech Briefs Magazine

This article first appeared in the July, 1998 issue of NASA Tech Briefs Magazine.

Read more articles from the archives here.