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GPS in the flow layer monitoring

The garmin gps application in the early mainly affect the precision orbit error, and the early GPS baseline is relatively short, the height difference is not, therefore, of the troposphere has not given much attention. As the accuracy of GPS orbit until recently much increased, tropospheric limit has been increased GPS positioning accuracy is an important obstacle. A basic assumption of zero elevation areas, the GPS receiver receives signals coming from the zenith direction, then the delay can reach 2.2-2.6m of this magnitude, and 2 hours up to the delay variation 10cm is not rare (so IGS analysis center parameters of the troposphere is a 2 hours interval). And because of this reality, tropospheric and random processes need to take the changes to be modeled.
The gps navigation system used in the study of the troposphere, IGS rapid orbit and orbital information for weather forecasting will play a major role. In addition, IGS GFZ by Germany's "IGS troposphere comparison and coordination center" to provide for every 2-hour series of troposphere zenith delay as a control point, for regional or local level of convection is, magellan gps can play the troposphere the role of absolute calibration delay.
GPS monitoring of different air and ground, satellite-based or space-based GPS radio occultation method for the determination of meteorological technology has wide coverage, vertical resolution is good, fast speed data acquisition. The principle of this technology is the GPS receiver on a LEO satellite (LEO) or aircraft platforms, the gps navigation receiver on the one hand to play the satellite (or aircraft) Precise Orbit Determination of the role, while Application of GPS radio occultation technology plays a role in atmospheric detectors. In 1997 the GPS / MET research project, confirmed that this idea is feasible. Scheduled for April 2000 launch of the CHAMP satellite TreadTang GPS radio occultation method to take advantage of the global tropospheric (including sub-atmospheric precipitation) determination.
In the next few years, there is Argentina's SAC-C, China Taiwan, COS-MIC, these LEO satellites have to be with Spaceborne GPS occultation method to measure the use of rail and air.
Gps systems for future use of spaceborne weather and the electron density cross-section values, combined with gps systemsground station data, make a layer off the image available for use. The next three years, GPS / MET project research is to be 6 times, which is expected in weather forecasting, space weather forecasting, weather monitoring, make a significant contribution.