DOI QR코드

DOI QR Code

Gravity Estimation by Using Low-Low Inter-Satellite Tracking Data

저궤도 위성간 추적데이터를 이용한 지구중력장 측정

  • 김정래 (한국항공우주연구원 유도제어그룹)
  • Published : 2003.10.01

Abstract

Accurate estimation of the Earth gravity field plays an important role in understanding the Earth geodynamic activities. After brief discussion on the objective of the gravity estimation, dedicated satellite missions for this purpose are described. Recently launched NASA/DLR Gravity Recovery and Climate Experiment (GRACE) mission, which consists of two co-orbiting low altitude satellites, is described. For the performance analysis, full numerical simulation was performed. The simulation procedure and its key instrument modelings are described. From the simulation results, a significant improvement on the Earth gravity field accuracy is expected.

정밀한 지구중력장 측정은 지구역학적인 현상을 이해하는데 매우 중요한 역할을 한다. 지구중력장 측정 목적에 관하여 간략히 언급한 뒤, 중력장 측정 전용위성을 이용한 측정 기법에 관해 고찰하였다. 최근에 발사된 NASA/DLR의 중력장 측정 전용위성인 Gravity Recovery and Climate Experiment (GRACE)의 개요 및 주요 관측기기들을 소개하였다. 두 개의 저궤도 위성으로 구성된 이 사업의 성능분석을 위한 시뮬레이션 기법과 관측기 모델링 방법 등을 소개하였다. 시뮬레이션 결과 GRACE를 이용하여 지구중력장 정확도를 상당히 향상시킬 수 있을 것으로 예상된다.

Keywords

References

  1. National Research Council, Committee on Earth Gravity from Space, Satellite Gravity and the Geosphere: Contributions to the Study of the Solid Earth and Its Fluid Envelope, National Academy Press, Washington DC, 1997.
  2. Vetter, J.R. Nerem,R.S., Cefola,P.J. and Hagar,H., "A Historical Survey of Earth Gravitational Models Used in Astrodynamics from Sputnik and TRANSIT to GPS and TOPEX", Advances in the Astronautical Sciences, Vol. 85 , 1993, pp.1253-1273.
  3. Reports for Mission Selection, "The Four Candidate Earth Explorer Core Missions: Gravity Field and Steady-State Ocean Circulation Mission", ESA SP-1233, July 1999.
  4. Wolff, M., "Direct Measurements of the Earth's Gravitational Potential Using a Satellite Pair", Journal of Geophysical Research, Vol. 74, No. 22, Oct. 15, 1969, pp. 5295-5300. https://doi.org/10.1029/JB074i022p05295
  5. Keating, T.P., Taylor,P., Kahn,W., and Lerch, F., "Geopotential Research Mission, Science, Engineering, and Program Summary", NASA TM-86240, 1986, pp. 69-73.
  6. Davis, E. S., Dunn, C. E., Stanton, R. H., and Thomas, J. B., "The GRACE Mission: Meeting the Technical Challenges," International Astronautical Federation, Paper IAF-99-B.2.05, Oct. 1999.
  7. MacArthur, J.L. and Posner, A.S., "Satellite-to-Satellite Range-Rate Measurement ", IEEE Transactions on Geoscience and Remote Sensing, Vol. GE-23, No. 4, Jul. 1985, pp. 517-523. https://doi.org/10.1109/TGRS.1985.289443
  8. Thomas, J.B., "An Analysis of Gravity-Field Estimation Based on Intersatellite Dual-1-Way Biased Ranging", Jet Propulsion Laboratory, JPL Publication 98-15, Pasadena, CA, May 1999.
  9. Rim, H.J., "TOPEX Orbit Determination using GPS Tracking System", Ph.D. Dissertation, Department of Aerospace Engineering and Engineering Mechanics, The University of Texas at Austin, December 1992
  10. Tapley, B.D., "Statistical Orbit Determination Theory", Advances in Dynamical Astronomy, D. Reidel Publishing Co., Holland, 1973, pp. 396-425.
  11. Kim, J.R., Simulation Study of a Low-Low Satellite-to-Satellite Tracking Mission, Ph.D. Dissertation, Department of Aerospace Engineering and Engineering Mechanics, The University of Texas at Austin, May 2000.
  12. Kim, J. and Tapley, B.D., "Error Analysis of a Low-Low Satellite-to-Satellite Tracking Mission", Journal of Guidance, Control, and Dynamics, Vol. 25, No. 6, 2002, pp. 1100-1106. https://doi.org/10.2514/2.4989
  13. Kim, J. and Tapley, B.D., "Simulation of Dual One-Way Ranging Measurements", Journal of Spacecraft and Rockets, Vol.40, No.3, 2003, pp. 419-425. https://doi.org/10.2514/2.3962
  14. Kosaka, M., "Evaluation Method of Polynomial Models' Prediction Performance for Random Clock Error", Journal of Guidance, Control, and Dynamics, Vol. 10, No. 6, 1987, pp. 523-527. https://doi.org/10.2514/3.20251
  15. Mazanek, D.D., Kumar, R.R., Seywald, H., and Min,Q., "GRACE Mission Design: Impact of Uncertainties in Disturbance Environment and Satellite Force Models", Advances in the Astronautical Sciences, Vol. 105, 2000, pp.967-986.
  16. University of Texas / Center for Space Research GRACE website http://www.csr.utexas.edu/grace/gravity