Hi all,
I am having an issue with some old navigation data that I was hoping to get some help with.
I have navigation data from a flight back in March, and I need to reprocess the SBET. We have recently moved to using an egps network and my problem is that the network we subscribe to deletes their data after 3 months, and my flight of interest was prior to that.
So, my question is, is there a way to change the date information of a rinex file so that it correlates with the nav data? My thought was to download a rinex file from a current date that the network has, and then to simply change the date to match the one of my flight. Not sure if this would work or not, but thought it could be worth a shot.
Any help would be greatly appreciated.
Thanks!
> Hi all,
>
> I am having an issue with some old navigation data that I was hoping to get some help with.
>
> I have navigation data from a flight back in March, and I need to reprocess the SBET. We have recently moved to using an egps network and my problem is that the network we subscribe to deletes their data after 3 months, and my flight of interest was prior to that.
>
> So, my question is, is there a way to change the date information of a rinex file so that it correlates with the nav data? My thought was to download a rinex file from a current date that the network has, and then to simply change the date to match the one of my flight. Not sure if this would work or not, but thought it could be worth a shot.
>
> Any help would be greatly appreciated.
>
> Thanks!
At risk of misunderstanding what you want, let me address what I think you want to do. By navigation data, I assume you mean the navigation file containing information about all satellites in the constellation allowing your processing software to compute the satellite positions at specific dates and times.
1. If you merely. Need a navigational message for a specific date to process with your observation data, these files are downloadable from the www.ngs.noaa.gov/CORS site
2. If you think that the navigation message does not vary by date/time you are mistaken. The RINEX navigation message contains information specific to a particular date and time. It provides a great deal of information in additional to satellite orbital elements. Do a search for RINEX navigation message and you will find details about the content of these files.
3. While the Navigation message for a specific date can be used with any observation file logged that date, observation files containing code and phase data logged at a site are unique to that site.