From our point of view, some improvements and enhancements in the format definition of the PCV table used by IGS/NGS are recommendable (e.g. identical header information). Furthermore, the format should be extended in order to represent also azimuthal PCV. Some explanations and discussions can be found here:
Standard and Extension of Antenna PCV Exchange Formats.
In general, confirmed by our absolute results of several other antenna
types, a complete set of individual azimuth- and elevation dependent PCV
should be used preferably. The Dorne Margolin type is one of the seldom
antenna types with almost none or only minor azimuthal PCV.
The ant-file corresponds to the spherical harmonic development, which was also used for the real-time calibration of degree 8 and order 5. The PCV are therefore azimuth and elevation dependent. The results of the ant-file are the best possible model of the PCV for the calibrated antenna.2) Elevation dependent PCV table (Geo++ -format, ane-file)
The ane-file contains only elevation dependent PCV, which were determined using an elevation dependent spherical harmonic develepment of degree 8. These PCV have been computed, because most of currently available RT-systems and post-processing software cannot handle azimuthal PCV. Existing azimuthal variations will distort the elevation dependent PCV and will degrade the accuracy of the PCV correction.3) Elevation dependent PCV table (IGS-format, only minor header difference to NGS)
(Format GEO++ PCV table)
identical to 2), reformatted4) Elevation dependent PCV table (NGS-format, only minor header difference to IGS)
identical to 2), reformatted0) Elevation dependent PCV Nullantenna (IGS-format), for relative PCV tables
As proposed in "Standard and Extension of Antenna PCV Exchange Formats", a Nullantenna is a convenient way to use relative and absolute PCV with currently existing relative PCV tables. Thus, a GPS user who wants to stay with relative PCV corrections can restore the missing absolute information by correcting for the Nullantenna type.
(Definition of "Nullantenna" and Antenna Type "Nullantenna")
Download the Absolute PCV Results for the AOAD/M_T Choke Ring Antenna (without dome):
AOAD/M_T, 7490400, SN 404
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