by National Aeronautics and Space Administration, National Technical Information Service, distributor in [Washington, DC, Springfield, Va .
Written in English
|Statement||William S. Schreiner, George H. Born.|
|Series||NASA contractor report -- NASA CR-194282.|
|Contributions||Born, George H., United States. National Aeronautics and Space Administration.|
|The Physical Object|
The performance of PRISM is very promising for predicting TEC and will prove useful for calibrating single frequency altimeter height measurements for ionospheric path delay. Abstract. This report investigates the potential of using Global Positioning System (GPS) data and a model of the ionosphere to supply a measure of the sub-satellite Total Electron Current (TEC) of the required accuracy (10 TECU rms) for the purpose of calibrating single frequency radar altimeter by: 2. The performance of the TOPEX dual-frequency altimeter ionosphere delay measurements has been evaluated by Imel () and Ruffini et al. (). Most historic altimeters were single-frequency (Ku. However, the majority of these missions (Seasat, Geosat, ERS-1, ERS-2 and GFO-1) carry single-frequency (Ku band, GHz) altimeters. Consequently, unlike the case of the TOPEX/POSEIDON (T/P) dual-frequency altimeter, the ionospheric path delay for these satellite data cannot be directly removed from the altimeter range measurements.
Unlike with dual frequency altimeters the path delay due to the ionosphere cannot directly be removed from the altimeter range measurements. For a radar altimeter operating at a frequency of GHz, such as the one carried by GFO, this path delay can be greater than 20 cm at solar maximum or during ionospheric storms due to disturbed solar. Ionospheric calibration for single frequency altimeter measurements. October (10 TECU rms) for the purpose of calibrating single frequency radar altimeter measurements. The accuracy of single-frequency ocean altimeters benefits from calibration of the total electron content (TEC) of the ionosphere below the satellite. Data from a global network of Global Positioning System (GPS) receivers provides timely, continuous, and globally well-distributed measurements of ionospheric electron content. product organization called International GNSS Service (IGS), which applications run from single frequency receivers (accurate mitigation of ionospheric delay), calibration of new altimeters (such as the SMOS mission) up to the potential use for increasing the performance of positioning based on carrier phase measurements.
single-site GPS data and is used to correct navigation radiomctric data for media effects. He continues to pursue efforts to improve the calibration system and validate its accuracy by comparisons with independent ionosphere measurements such as Very Long Baseline Interferometry, integrated dual-frequency Doppler, and theTOPEX dual- frequency. Ionospheric models provide the only recourse short of adding a second frequency to the altimeter. Unfortunately, measurements of the ionosphere are lacking over the oceans or ice sheets where they are most needed. to extend ionospheric measurements by simply adding a GPS receiver and downward-pointing antenna to satellites carrying single. Ionospheric Systems Development Group atJP1,, has been studying the ionospberc using GPS for six years and is a co-developer ofthe GPS-based global ionospheric mapping (GIM) tcchniquc. His current work is focused on improving and validatingGIM, global ionospheric calibration of single-frequency ocean altimetry missions. Get this from a library! Ionospheric calibration for single frequency altimeter measurements. [William S Schreiner; George H Born; United States. National Aeronautics and Space Administration.].