Evaluation of Geometric and Atmospheric Doppler for GNSS-RO Payloads

Document Type : Research Article

Authors

Iranian Research Organization for Science & Technology, Tehran, Iran

Abstract

To reduce the sampling rate in global navigation satellite system (GNSS)-radio occultation receivers, it is essential to establish a suitable estimation of Doppler frequency from the received signal in the satellite onboard receiver. This receiver is usually located on low earth orbit satellite and receives GNSS satellites signal in the occultation situation. The occurred Doppler on the signal contains the Geometric and Atmospheric segments. The Geometric Doppler’s value depends on the orbital situation of transmitter and receiver. However, Atmospheric Doppler depends on the signal propagation environment conditions. To investigate the nature of these two types of Doppler, we establish different missions on STK software environment for receivers located on different orbits from 450km altitude to 800km and 1500km with different orbital parameters and by considering the Global Positioning System satellites as the transmitters. We also study the value and nature of the Atmospheric Doppler by utilizing and analyzing the data produced by the COSMIC Data Analysis and Archive Databases Center. In signal tracking part of the receiver, the variation of Doppler is also important, in addition to the Doppler that is called phase acceleration. Therefore, the derivatives of Geometric Doppler related to the LEO satellites in different altitudes need to be considered.

Keywords

Main Subjects


[1] W. H. Bai, Y. Q. Sun, Q. F. Du, G. L. Yang, Z. D. Yang, P. Zhang, Y. M. Bi, X. Y. Wang, C. Cheng and Y. Han, “An introduction to the fy3 gnos instrument and mountain-top tests,” Atmos. Meas. Tech., vol. 7, p. 1817–1823, June 2014.
[2] S. Sokolovskiy, “Method and System for determining The phase and amplitude of a radio occultation signal ” U.S. Patent 6,731,906 B2, May 2004
[3] S. Sokolovskiy, “Tracking Tropospheric Radio Occultation Signals from Low Earth Orbit,” Radio Sci., vol. 36, no. 3, p. 483–498, June 2001.
[4] S. Sokolovskiy, C. Rocken, W. Schreiner, D. Hunt and J. Johnson, “Post processing of l1 gps radio occultation signals recorded in open-loop mode,” Radio Sci., vol. 44, p. 1–13, May 2009.
[5] S. Sokolovskiy, C. Rocken, D. Hunt, W. Schreiner, J. Johnson and D. Masters, “GPS Profiling of the Troposphere from Space: Inversion and Demodulation of the open-loop radio occultation signals,” Geophysical Research Letters, vol. 33, no. 3, p. 483–498, April 2006.
[6] C. O. Ao, G. A. Hajj, T. K. Meehan, D. Dong, B. A. Iijima, A. J. Mannucci and E. R. Kursinski, “Rising and Setting GPS occultations by use of open-loop tracking,” Journal of Geophysical Research: Atmospheres, vol. 114, no. D4, February 2009.
[7] W. Schreiner, C. Rocken, S. Sokolovskiy, S. Syndergaard and D. Hunt, “Estimates of the Precision of GPS Radio Occultations from COSMIC/FORMOSAT-3,” Geophysical Research Letters., vol. 34, 2007.
[8] R. A. Anthes and e. al., “The COSMIC/FORMOSAT-3 mission: Early results,” Bull. Am. Meteorol. Soc., vol. 89, p. 313–333, 2008.
[9] S. B. Healy and J. N. The´paut, “Forecast Impact Experiment with GPS Radio Occultation Measurements,” Q.J.R. Meteorol. Soc., vol. 132, p. 605–623, 2006.
[10] L. Cucurull, J. C. Derber, R. Treadon and R. J. Purser, “Preliminary Impact Studies using Global Positioning System radio occultation profiles at NCEP,” Mon. Weather Rev., vol. 136, p. 1865– 1877, 2008.
[11] L. B. Hande, S. T. Siems, M. J. Manton and D. H. Lenschow, “An evaluation of COSMIC Radio Occultation Data in the Lower Atmosphere over the Southern Ocean,” Atmos. Meas. Tech., vol. 8, no. 1, pp. 97-107, Jan 2015.
[12] M. E. Gorbunov, “Radio-Holographic Analysis of Microlab-1 Radio Occultation Data in the Lower Troposphere,” Journal of Geophysical Research., vol. 107, no. D12, 2002
[13] E. R. Kursinski, G. A. Hajj, S. S. Leroy and B. Herman, “The GPS Radio Occultation Technique,” Terr. Atmos. Oceanic Sci., vol. 11, no. 1, p. 53–114, 2000.
[14] M. E. Gorbunov, “Canonical Transform Method for Processing Radio Occultation Data in the Lower Troposphere,” Radio Sci., vol. 37, no. 5, 2002.
[15] M. E. Gorbunov and L. Kornblueh, “Analysis and validation of GPS/MET Radio Occultation Data,” Journal of Geophysical Research, vol. 106, no. D15, p. 161–169, 2001.
[16] A. S. Nielsen, A. S. Jensen, M. S. Lohmann, H. H. BenFull, “Spectrum Inversion of Radio Occultation Signals,” Radio Sci., vol. 38, no. 3, 2003.
[17] M. E. Gorbunov and L. Kornblueh, “Analysis of Wave Fields by Fourier Integral Operators and their Application for Radio Occultations,” Journal of Geophysical Research, vol. 39, 2004.
[18] A. S. Jensen, M. S. Lohmann, H. H. Benzon and A. S. Nielsen, “Geometrical Optics Phase Matching of Radio Occultation Signals,” Radio Sci., vol. 39, 2004.
[19] C. O. Ao, T. K. Meehan, G. A. Hajj, A. J. Mannucci and G. Beyerle, “Lower Troposphere Refractivity bias in GPS Occultation Retrievals,” Journal of Geophysical Research., vol. 108, no. D18, 2003.
[20] G. Beyerle, M. E. Gorbunov and C. O. Ao, “Simulation studies of GPS radio occultation measurements,” Radio Sci., vol. 38, no. 5, 2003.
[21] K. Hocke, A. G. Pavelyev, O. I. Yakovlev, L. Barthes and N. Jakowski, “Radio Occultation Data Analysis by the Radio Holographic method,” J. Atmos. Sol-Terr. Phys, vol. 61, p. 1169–1177, 1999.
[22] S. Sokolovskiy, C. Rocken, W. Schreiner and D. Hunt, “On the uncertainty of Radio Occultation Inversions in the lower troposphere,” Journal of Geophysical Research, 2010.
[23] C. Rocken and e. al., “Analysis and validation of GPS/MET data in the Neutral Atmosphere,” Journal of Geophysical Research., vol. 102, no. D25, pp. 29,849–29,866, 1997.
[24] C. Marquardt, K. Schollhammer, G. Beyerle, T. Schmidt, J. Wickert and C. Reigber, “Validation and Data Quality of CHAMP Radio Occultation Data, in First CHAMP Mission Results for Gravity,” Magnetic and Atmospheric Studies, p. 384–396, 2003.
[25] G. A. Hajj, C. O. Ao, B. A. Iijima, D. Kuang, E. R. Kursinski, A. J. Mannucci, T. K. Meehan, L. J. Romans, M. de la Torre Juarez and T. P. Yunck, “CHAMP and SAC-C Atmospheric Occultation Results and Inter Comparisons,” Journal of Geophysical Research., vol. 109, no. D06109, 2004.
[26] S. V. Sokolovskiy, “Effect of super refraction on inversions of Radio Occultation Signals in the Lower Troposphere,” Radio Sci., vol. 38, no. 3, 2003.
[27] F. Xie, S. Syndergaard, E. R. Kursinski and B. Herman, “An Approach for Retrieving Marine Boundary Layer Refractivity from GPS occultation data in the Presence of Super-Refraction,” J. Atmos. Oceanic Technol., vol. 23, p. 1629–1644, 2006.
[28] C. O. Ao, “Effect of Ducting on Radio Occultation measurements: An Assessment based on High-Resolution Radio sonde soundings,” Radio Sci., vol. 42, no. RS2008, 2007.
[29] G. Beyerle, S. Heise, T. Schmidt, J. Wickert and M. Rothacher, “Tracking GPS radio Occultation Signals in the Lower Troposphere: CHAMP Observations and Simulation Studies,” DMI Technical Report 05-11, 2005.
[30] S. Gleason and D. Gebre-Egziabher, GNSS Applications and Methods, Boston: Artech House , 2009.
[31] M. Bonnedal, A. Carlström, J. Christensen and M. Sust, “Apparatus and Method for Performing Open Loop Tracking of a Signal”. USA Patent US6720916 B2, 13 April 2004.
[32] E. R. Kursinski, “Observing Earth’s Atmosphere with Radio Occultation Measurements using the Global Positioning System,” Journal of Geophysical Research: Atmospheres, vol. 102, no. D19, pp. 23429-23465, 1997.
[33] Man Feng, Detection of high latitude ionospheric Irregularities from GPS, Ph.D. Dissertation, Radio Occultation Department of Geometrics Engineering , University of Calgary, May 2010.
[34] Sokolovskiy, Sergey, “Modeling and Inverting Radio Occultation Signals in the Moist Troposphere”, Radio Sci., vol. 36, no. 3, pp. 441-458, 2001.
[35] Sergey, Sokolovskiy,”Modelling of tropospheric RO signals, Acquisition of the Tropospheric RO Signals” UCAR –COSMIC project.