I have read previous threads and realize I am not the only person who has got the "OPUS-RS aborting, fewer than 3 usable reference stations remain" back. I took (2) 30 min observations back to back on 2 different points, one came back with good results and the other aborted with this message. My questions is why? I had enough CORS data on one session but not the other 30 mins later? I realize I may need to edit the rinex file but have no clue as to what to look for or how the file is setup. From my basic knowledge it appears to be positions from each sv during the session? Any help in the right direction would be appreciated.
The TEQC program can be downloaded for free and can help you edit the Rinex if you don't want to do it manually like a text file. It can split it into different time increments, etc. How long did you wait to submit the file? I always have problems when I send them in the same day.
Dan Patterson, post: 452255, member: 1179 wrote: The TEQC program can be downloaded for free and can help you edit the Rinex if you don't want to do it manually like a text file. It can split it into different time increments, etc. How long did you wait to submit the file? I always have problems when I send them in the same day.
I downloaded teqc but didn't have much luck as a new user. I sent on Friday and have played with it since then on wordpad. I finally notice some of the epochs were smaller than the rest, deleted those, and just have got a solution a few mins ago. Thanks.
Each epoch has a header with time and date and SV numbers (and how many satellites). Then range and phase measurements from each satellite (often on two lines for each satellite depending on how many frequencies, etc are used.
Look for epochs with few satellites. Delete those epochs including the header line. DO NOT USE A WORD PROCESSOR, use a text editor. Keep a backup of the original file
John Hamilton, post: 452268, member: 640 wrote: Each epoch has a header with time and date and SV numbers (and how many satellites). Then range and phase measurements from each satellite (often on two lines for each satellite depending on how many frequencies, etc are used.
Look for epochs with few satellites. Delete those epochs including the header line. DO NOT USE A WORD PROCESSOR, use a text editor. Keep a backup of the original file
That is exactly what I did and it worked. So is using wordpad not a good idea? What should I use?
I have always used NOTEPAD, and find that it works just fine for me.
On a related note (no pun intended), some RINEX files that I download from UNAVCO, look "strung together" when initially opened in NOTEPAD. If I open them in WORDPAD, and then immediately save them (nothing in between), then open them in NOTEPAD, they are FINE, and I proceed from there as usual.
Loyal
Fewer than 3 useable CORS is a comment on the actual CORS data available. I imagine one of the CORS used in your first solution did not have good clean data for the second solution. It is possible that that poor data gets fixed or is resubmitted to CORS at a later time. Typically that comment goes away the following day. OPUS-RS cannot be expected to provide a same day solution every days as OPUS does.
I do most of my editing in WordPad as it is simply removing a few epochs. If it is more complicated I use WINteqc.
As what to look for, OPUS-RS uses L1, L2, C1/P1 & C2/P2 data. At the beginning of a file it is common to have L1 & L2 and the other data is not up to snuff. C1/P1 & C2/P2 are the actual calculated ranging values in meters from the satellite to your antenna, in the range from 20,000,000m straight up to 25,000,000m 10?ø above the horizon. Typically after a minute or two the data is acceptable. OPUS-RS actually does a CORS to CORS solution before it adds in your file for a second solution. It is possible that OPUS-RS never seriously looks at your data because it has nothing good to start with from the CORS.
Depending on how your receiver is set up C1 is standard, P1 has been standard in Ashtech Receivers for years. P2 was available from all receivers, C2 is available only from the newer GPS satellites, half the constellation now. Your receiver may be set up to record only P2 from the older and C2 from the newer GPS, take a look at the RINEX. That was a problem for a while, as OPUS-RS would automatically use P1 instead of C1 if it was available but was not using the either or option with the half P2 half C2 data. That is now fixed.
Paul in PA
OK, so some rinex files are dos (carriage return and line feed at the end of each line) and some rinex files are unix (only line feed at the end of each line). I use a very powerful text editor called ultraedit which recognizes this and displays both correctly, and also has conversions between the two. I can tell you that reading a unix file is more difficult programmatically in dos than is reading a dos file.
about the difference:
http://www.cs.toronto.edu/~krueger/csc209h/tut/line-endings.html
It all depends on the source of the rinex file. TBC will read either type with no problem. I had to do some extra programming in order to properly read the unix style files into my databases. First I had to count the number of line feeds, then create an array dimensioned to that number, then scan through and fill the array with the file offsets to each line feed, and finally read the file as a random access file using those file positions. The dos version reads right in.
Thanks everyone for their input. I normally learn new things the hard way (by what doesn't work). It is nice to be able to have someone way more experienced than me to ask questions to. I think the rover was still recording data after I had pulled up and moved around, this probably didn't help OPUS. After deleting anything past my 30 min observation everything came back clean. Live n Learn.
WordPad and Word can insert control characters that mark formatting, etc. Open a Word file sometime and click the paragraph symbol (backwards P with a vertical line through it) in the center of the Home tab to see some of the extra symbols. Saving a .doc or .docx file as .txt should strip all that out but can affect the spacing/formatting of the actual text. Software parsing what it thinks is a ASCII-only file will choke on the control characters or the messed up text. Notepad doesn't do that because it doesn't support any formatting that is stored within the text file, it's all handled by display.
What Loyal is doing with the UNAVCO RINEX files is converting a unix-style text file (no line feeds, so all lines run together) into a DOS-style text file by resaving it out of WordPad.
mkennedy, post: 452322, member: 7183 wrote: WordPad and Word can insert control characters that mark formatting, etc. Open a Word file sometime and click the paragraph symbol (backwards P with a vertical line through it) in the center of the Home tab to see some of the extra symbols. Saving a .doc or .docx file as .txt should strip all that out but can affect the spacing/formatting of the actual text. Software parsing what it thinks is a ASCII-only file will choke on the control characters or the messed up text. Notepad doesn't do that because it doesn't support any formatting that is stored within the text file, it's all handled by display.
What Loyal is doing with the UNAVCO RINEX files is converting a unix-style text file (no line feeds, so all lines run together) into a DOS-style text file by resaving it out of WordPad.
YUP
