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Correction of Single Frequency Altimeter Measurements for Ionosphere DelayThis study is a preliminary analysis of the accuracy of various ionosphere models to correct single frequency altimeter height measurements for Ionospheric path delay. In particular, research focused on adjusting empirical and parameterized ionosphere models in the parameterized real-time ionospheric specification model (PRISM) 1.2 using total electron content (TEC) data from the global positioning system (GPS). The types of GPS data used to adjust PRISM included GPS line-of-sight (LOS) TEC data mapped to the vertical, and a grid of GPS derived TEC data in a sun-fixed longitude frame. The adjusted PRISM TEC values, as well as predictions by IRI-90, a climatotogical model, were compared to TOPEX/Poseidon (T/P) TEC measurements from the dual-frequency altimeter for a number of T/P tracks. When adjusted with GPS LOS data, the PRISM empirical model predicted TEC over 24 1 h data sets for a given local time to with in a global error of 8.60 TECU rms during a midnight centered ionosphere and 9.74 TECU rms during a noon centered ionosphere. Using GPS derived sun-fixed TEC data, the PRISM parameterized model predicted TEC within an error of 8.47 TECU rms centered at midnight and 12.83 TECU rms centered at noon. From these best results, it is clear that the proposed requirement of 3-4 TECU global rms for TOPEX/Poseidon Follow-On will be very difficult to meet, even with a substantial increase in the number of GPS ground stations, with any realizable combination of the aforementioned models or data assimilation schemes.
Document ID
19970026888
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Schreiner, William S. (Colorado Univ. Boulder, CO United States)
Markin, Robert E. (Colorado Univ. Boulder, CO United States)
Born, George H. (Colorado Univ. Boulder, CO United States)
Date Acquired
September 6, 2013
Publication Date
March 1, 1997
Publication Information
Publication: IEEE Transactions on Geoscience and Remote Sensing
Volume: 35
Issue: 2
ISSN: 0196-2892
Subject Category
Geophysics
Report/Patent Number
NAS 1.26:204320
NASA-CR-204320
Funding Number(s)
CONTRACT_GRANT: NAG1-1491
Distribution Limits
Public
Copyright
Public Use Permitted.

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