rtklibexplorer / RTKLIB

A version of RTKLIB optimized for low cost GNSS receivers, especially u-blox receivers. It is based on RTKLIB 2.4.3 and is kept reasonably closely synced to that branch. This software is provided “AS IS” without any warranties of any kind so please be careful, especially if using it in any kind of real-time application.
http://rtkexplorer.com/
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ANTEX: PCV with azimuth, full freq range, ANTEX 2, SINEX metadata #533

Open ourairquality opened 1 week ago

ourairquality commented 1 week ago

The ANTEX support was limited, perhaps good for GPS frequencies L1 and L2, but beyond that it was limited, and using more signals across multiple systems it was problematic. If the PCO is missing or wrong for some signals then that makes the solution difficult or throws it off, often showing up as an error in the height first. While addressing those issues, also added support for PCV azimuth, and for ANTEX 2 which in turn needed some limited support for satellite meta data SINEX files.

This helps if not using matched antennas, and if using a competent base for RTK.

It assumes the antennas are horizontal and pointing north. There is no support in the code yet to consider the rover heading.

Added interpolation for the receiver PCO an PCV across frequencies. If a low end antenna has at least a GPS L1 and L2 calibration then that will be used for other signals in the same band. Even supplying the L1 and L2 PCO can help and this is often printed on the label.

Some antennas with an otherwise tight PCO can vary a lot over frequency in the lower frequency band, 10mm+, so interpolation will not always be great particularly in the lower frequency band.

The ANTEX 2 files are at https://files.igs.org/pub/station/general/atx_alternative/atx2/ and the meta data at https://files.igs.org/pub/station/general/ ANTEX 2 adds nothing over ANTEX 1 for the solution and should give the same solution, it was just a small thing to add support while look over this code. ANTEX 2 has less redundant information, almost half the file size. Some example options for ANTEX 2: file-satmetafile =igs_satellite_metadata.snx file-satantfile =igs20_sat.atx2 file-rcvantfile =igs20_rcv.atx2

The windows app GUI support is not done, that just means there is no file selection for the ANTEX 2 meta data file, it should otherwise work, and ANTEX 2 adds nothing to the solution.