Analysis of radial orbit errors of ERS1, and the development of supertailored gravity models
Abstract
The altimetry mission of the future ESA remote sensing satellite ERS1 requires very accurate orbit solutions, of which in particular the radial position component should have an accuracy of approximately 10 cm. This paper presents some investigations into the possibility of reducing the radial position error due to the earth's gravity field, which is by far the largest contributing error source.
With a detailed harmonic analysis of the ERS1 orbit a number of gravity field model terms are identified which produce the major radial orbit perturbations. These dominant terms are adjusted in a leastsquares orbit determination and parameter estimation procedure using actual SEASAT laser tracking observations and altimeter height measurements. The initial gravity model is the NASA GEML2 model derived from satellite tracking data only, with an emphasis on LAGEOS data. The resulting supertailored model yields a significantly improved radial accuracy relative to GEML2, but fails to reach the accuracy of the SEASATtailored model PGSS4.
Finally, the SEASAT altimeter residuals and the residuals of the crossover differences are analyzed in the frequency domain by applying a special filtering technique which separates the major radial orbit error and geoid error contributions.
 Publication:

Advances in Space Research
 Pub Date:
 1986
 DOI:
 10.1016/02731177(86)903728
 Bibcode:
 1986AdSpR...6i.183Z
 Keywords:

 Earth Gravitation;
 Error Analysis;
 Ers1 (Esa Satellite);
 Gravitational Effects;
 Satellite Altimetry;
 Satellite Orbits;
 Satellite Perturbation;
 Harmonic Analysis;
 Satellite Tracking;
 Seasat Satellites;
 Geophysics