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Flight Performance Analysis of the GRACE Inter-Satellite Ranging Instrument

GRACE 위성 간 거리측정기 비행성능 분석

  • Published : 2006.08.01

Abstract

GRACE (Gravity Recovery and Climate Experiment) is the first dedicated gravity mapping mission. Its primary measurements are the distance changes between two co-orbiting low earth satellites. GRACE is a joint development by NASA and German DLR and was launched in March 2002. GRACE improves the Earth gravity model accuracy by nearly two factor of magnitude over pre-launch models. After brief description of the GRACE primary instrument, inter-satellite ranging system, its flight status and preliminary performance evaluation is presented. Ranging system error models, which were not included in the pre-launch performance model and design specifications, are identified through analyzing the flight data. Base on this analysis, future research topics on the GRACE instrument performance analysis are discussed.

2002년 3월에 발사 된 GRACE (Gravity Recovery and Climate Experiment)는 미국과 독일 합작으로 개발된 최초의 지구중력장 측정 전용 위성으로 동일한 궤도를 비행하는 두 개의 위성 사이 거리 변화를 측정하여 지구 중력장을 추정하는 사업이다. 위성 발사 후 이전 보다 수 십배 정확한 지구중력장 모델을 생성하였으며, 지구중력장 변화도 30일마다 추정하고 있다. GRACE 위성의 핵심 관측기인 위성간 거리 측정기의 원리에 대해 소개하고, 운용 결과 및 성능에 대해 소개 하였다. 발사 전 성능 분석 단계에서 고려되지 못했던 거리측정기 오차 요인에 대해 분석하고, 향후 연구 방향을 제시 하였다.

Keywords

References

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