DPOS 24hr delay?

Matt Johnson

Well-Known Member
5PLS
To be more precise, data for the current day should be available after midnight UTC or 8PM EST with daylight savings.
 

avoidthelloyd

Active Member
Why were we able to do this before recently? It was part of my Hybrid RTK process... I like being able to setup a new base on Auto, go tie section corners, come back, DPOS the data and it tie into the other section corners I already have previous data for. All in the same day so I can finish the job.
 

John Rosco

Administrator
JAVAD GNSS
5PLS
See https://www.ngs.noaa.gov/CORS/data.shtml

IE: The GNSS data collected at NCN stations are made available to the public by NGS in Receiver INdependent EXchange (RINEX) format.
Most data are available within 1 hour (60 minutes) from when they were recorded at the remote site,
and other sites have a delay of 24 hours (1440 minutes).
 

Steve Hankins

Active Member
5PLS
Why were we able to do this before recently? It was part of my Hybrid RTK process... I like being able to setup a new base on Auto, go tie section corners, come back, DPOS the data and it tie into the other section corners I already have previous data for. All in the same day so I can finish the job.
I understand your workflow, but I don't think this is an issue on the JAVAD side of the equation, it, JAVAD, has to wait until the data is available just like OPUS. A possible workaround may be to set your autonomous base, then use reverse shift function to tie in to one of the points you mentioned in your post, that you already have data on. You don't have to do that function first, you can locate the new positions first, and the use the reverse shift to tie it all together. Shawm Billings has an excellent YouTube video to explain the procedure. Please feel free to give me a call if you have questions, 501-620-0608.
 

avoidthelloyd

Active Member
I understand your workflow, but I don't think this is an issue on the JAVAD side of the equation, it, JAVAD, has to wait until the data is available just like OPUS. A possible workaround may be to set your autonomous base, then use reverse shift function to tie in to one of the points you mentioned in your post, that you already have data on. You don't have to do that function first, you can locate the new positions first, and the use the reverse shift to tie it all together. Shawm Billings has an excellent YouTube video to explain the procedure. Please feel free to give me a call if you have questions, 501-620-0608.
I understand what you are suggesting. It doesn't answer my question as to why we have been able to use the Hybrid RTK procedure up until recently. I'm saying for the past 7 years, I have been able to use the workflow I described above. That was one of the selling points to me for Javad.

I'm wondering what has changed? @John Rosco mentioned some stations have a 24 hour delay, but I'm using the same stations I have used around here for 7 years. If the CORS GNSS data is being delayed there is nothing to do, but if it hasn't changed, I assumed (maybe incorrectly) that J-Field or something was changed.

Here is a video of a not so handsome bloke doing a similar workflow.

 

Matt Johnson

Well-Known Member
5PLS
Here is a video of a not so handsome bloke doing a similar workflow.
Watch and listen to what Shawn says at the 10:20 mark. He is only processing base-rover data and not the base point with CORS data. He states "We are only going to be processing from the base to the rover since CORS data is not available until typically the next day"


If you were able to process with CORS data sooner midnight UTC in the past, it was because DPOS was able to retrieve hourly files in the past but is now only retrieving daily uploads.
 

Matt Johnson

Well-Known Member
5PLS
We used to be able to send data to DPOS after the top of the hour and it worked flawlessly for years.
I think in the past it was downloading hourly files in some areas but now I think it may only download daily files now. I do not know the details of why the hourly files can't be downloaded anymore.
 

John Rosco

Administrator
JAVAD GNSS
5PLS
Please be advised, DPOS is 'provided as a' free JAVAD service', but is subject to the 'DPOS server' being able to retrieve 'reference station observation' as provided "in the USA' by the availability of the "NGS Server" . . .

The NGS are updating their capability with their more recent 'modernization service'.
So there will be some 'consequences' for all users.
"Hourly RINEX base reference files' may not always be available, but next day 24hr RINEX files will always be available (as applicable to DPOS or CORS processing etc...)
 

John Rosco

Administrator
JAVAD GNSS
5PLS
Wait a day before submitting your file:
Post-Processing (in the US) will use the best CORS and Orbit information available "at the time you upload your data" . . .
While many CORS 'reference data' are archived within 30-minutes past the hour, some aren't available until the next day (after Midnight UTC).
 
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