Datensatz

Zusammenfassung

In this report, we present the results of elaboration of methods of inversion of the
GPS /MET satellite data taking diffraction and multipath effects into account. The first
results of the GPS /MET program of sounding of the Earth’s atmosphere by means of a
Low Earth Orbit satellite implemented with a GPS receiver, indicated that in the lower
troposphere, the phase and amplitude of the signal received undergo strong oscillations.
This effect is a consequence of multipath propagation resulting from complicated structure
of the atmospheric refractivity in the tropical regions. We propose a method of processing
the phase measurements, based on the theory of diffraction. The method was tested in
processing GPS/MET radio soundings. Comparison of the reconstructed profiles of the
temperature and humidity with those derived from the radiosonde measurements extracted
from the NMC Global Atmospheric Circulation Model, indicates validity of the method
proposed. An approach to the nudging assimilation of the GPS /MET refractometric data is proposed.