Spectracom GSG-5 series, Руководство пользователя с руководством по SCPI

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Note: The GSG also supports simulation of ionosphere delays using files in the
IONEX format.
Tropo model
A number of tropospheric models are supported by the device. These are:
Saastamoinen model. The model is based on Saastamoinen, J., 'Atmospheric Correction
for the Troposphere and Stratosphere in Radio Ranging of Satellites,' The Use of Arti
ficial Satellites for Geodesy, Geophysics Monograph Series, Vol. 15., American Geo
physical Union, 1972
Black model. The model is based on Black H., ‘An Easily Implemented Algorithm for the
Tropospheric Range Correction’, JOURNAL OF GEOPHYSICAL RESEARCH, 1978
Goad&Goodman , a tropospheric model based on Goad and Goodman(1974), "A
Modified Hopfield Tropospheric Refraction Correction Model", 1974
STANAG model. The model is based on NATO Standardization Agreement (STANAG)
Doc. 4294, Appendix 6.
The tropospheric model can also be set to Off , and no troposperic delays are used in sim
ulation. Under normal testing conditions, one of the tropospheric model
should
be used.
The tropospheric model also allows for the temperature, pressure and humidity to be con
figured:
Temperature : to be specified in degrees Celsius
Atmospheric pressure : in millibars
Humidity : relative humidity in percent.
The graph below illustrates the delays for the different models available, using default values
for environmental conditions.
Note that the troposheric delay added to satellites with low elevation angles are ‘capped’ at a
maximum value. The capping delay value and the elevation angle are a function of the model
used.
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CHAPTER
3
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User Manual GSG-5/6 Series Rev. 26
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