An Improved Strategy for Determining Earth Satellite Orbits by Radio
Abstract
For satellite orbit determination, the most accurate observable available today is microwave phase, differenced between observing stations and between satellites to cancel both transmitter and receiver related errors. For maximum accuracy, the integer cycle ambiguities of such observations must be resolved. To perform this ambiguity resolution, a bootstrapping strategy is effective. The tracking stations must have a wide ranging progression of spacings. Then, by conventional 'integrated Doppler' processing of the observations from the most widely spaced stations, the orbits can be determined well enough to permit resolution of the ambiguities of the observations from the most closely spaced stations. The resolution of these ambiguities can reduce the uncertainty of the orbit determination enough to enable ambiguity resolution for more widely spaced stations, which will reduce the orbital uncertainty further, and enable ambiguity resolution resolution for still more widely spaced stations, and so on. In a test of this strategy with a total of six tracking stations, both the formal and the actual errors of determining NAVSTAR Global Positioning System satellite orbits were reduced by a factor of two.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 27, 1988
- Accession Number
- ADA205826
Entities
People
- Charles C. Counselman Iii
- Richard I. Abbot
Organizations
- Massachusetts Institute of Technology