HR: 1340h
AN: G33A-0895 [Abstracts]
TI: Analysis of the Characteristics of the GRACE Dual One-Way Ranging System
AU: * Ko, U
EM: udko@yahoo.com
AF: Center for Space Research of the University of Texas at Austin, 3925 West Braker Lane,
Suite 200, R1000, Austin, TX 78759-5316, United States
AU: Tapley, B D
EM: tapley@csr.utexas.edu
AF: Center for Space Research of the University of Texas at Austin, 3925 West Braker Lane,
Suite 200, R1000, Austin, TX 78759-5316, United States
AU: Ries, J C
EM: ries@csr.utexas.edu
AF: Center for Space Research of the University of Texas at Austin, 3925 West Braker Lane,
Suite 200, R1000, Austin, TX 78759-5316, United States
AU: Bettadpur, S V
EM: srinivas@csr.utexas.edu
AF: Center for Space Research of the University of Texas at Austin, 3925 West Braker Lane,
Suite 200, R1000, Austin, TX 78759-5316, United States
AB:
The GRACE (Gravity Recovery and Climate Experiment) is a dedicated space-borne mission to map the Earth's
gravity field with unprecedented accuracy. The primary measurement is the range change between the two
satellites, which reflects the gravity perturbation difference between the two locations. The range change is
measured by a high-accuracy microwave ranging system based on the Dual One-Way Ranging (DOWR) concept.
In this paper, we analyze the characteristics of the DOWR and develop possible improvements to its computation
from the raw observables. In particular, we investigate the high frequency noise that appears to exceed what we
would expect from the design specifications. Possible causes are a higher than expected frequency instability in
the ultra-stable oscillator, or undesirable effects from other instrument components or external environmental
influences. Based on an improved understanding of the instrument characteristics, we investigate possible
improvements to the DOWR processing, especially addressing the attenuation of the excessive high frequency
noise in the data.
DE: 1219 Gravity anomalies and Earth structure (0920, 7205, 7240)
DE: 1241 Satellite geodesy: technical issues (6994, 7969)
DE: 6994 Instruments and techniques (1241)
SC: Geodesy [G]
MN: 2007 Fall Meeting