Got some formal training from a rep 2 days ago for static work and post processing with GNSS........
Funny, all results were float and failed QC.

Did a job yesterday, simple static collection to measure 5 points.

Post processed today using GNSS and all solutions float and fail QC.

Noticed that timers are going wonkers on PM3's in field.

While logging static data several times I tapped NAV key to see how things were going, the hour of day changed by 1 hour several times.

Also the bars indicating strenght of signal were hollow except for 2 WAAS birds and the bars changed from solid to hollow in middle of day.

I have a lot of successful experience doing static work with PM2's and using Solutions.

OK.........I give ???????

Can use PM3's for RTK work using Carlson but have NEVER successfully used for static or S-N-G.

W

Let's start with a simple question, were the receiver antennas absolutely static, that is, did you have a bipod or other steady rod holder?

Paul in PA

Yep.......both receivers in tripods.
No wind, good sky view. PDOP 1.4 with 12 birds tracking. Observation timer said good for minimum 6 mile vectors, the actual distances I was measureing never exceeded 1,000 ft.


Same procedures I have followed doing static work successfully many times with PM2's and Solutions.

Totally baffled.

W

Send me a set of files.

Paul in PA

What are your tolerances set to? They are user defined if they do not meet your threshold they will fail. I would check your project settings.

Wayne,

I'd like to take a look at your data. Would you please send your base and rover files?
I'm traveling this week, so please send to
cjsmith1@ix.netcom.com
Don't know that I can fix the files, but hopefully I can at least give you a reason for the results you got.

Linda

About a year ago I did a stop and go survey and found that one of the times I hit the nav key that stopped the logging even though it appeared to be going - since then I use the nav key (and the rest of the keys) very carefully - even a short tap - less then the full one second firm key press has sent the pm3 over the edge. Usually shows up on the nav screen as points not being where they are or overlapping on the nav map - in the files the observation times were short or nonexistant. Since then, twice I had to reset the pm3 and the lack of signal or lost sats was the symptom. With the latest software I rarely run into this, but the best way to make the pm3 crazy is to just tap the buttons very quickly. I almost get paranoid about the buttons, but if in doubt ckeck the sat screen for lost signal. Once the signal was lost it took a while to get the pm3 running again where it knew where it was.

Ken

Am I being led astray by observation timer ?

Timer is telling me good for 8 miles when I am measuring 1/4 mile. But total time is like 15 minutes and my 95% confidence is about 1/2 foot with float and fail QC which is set for 0.06 + 1 PPM in feet.

W

I am uncertain of how the internal timers decide whe enough is enough. That is do they actually figure PDOP based on satellite geometry or do they just assume that 8 satellites should give good geometry no matter where they are placed.

Learn to check your sky view, is your receiver really locked into enough satellites with good geometry. There are several periods during the day when I see 7 or 8 satellites and PDOP is 4.5 or better. That 15 minutes would be a bad 15 minutes to only do a 15 minute observation.

The PDOP calculation could be misleading assuming a good WAAS position. Even a WAAS satellite can have a bad day.

BTW sun spot activity has just picked up, heading into a new high activity cycle.

Figure out how much a second trip to the site costs and adjust your minimum occupations accordingly. Some days though the stars are not in your favor.

Somedays even data needs professional psychoanalysis. That would be Linda. I can sometimes catch the easy problems. Timers are guides, you have eyes to see the sky view and experience in your gut. Use all three.

Paul in PA

You sent me the files while I was posting above. Your data looks good. Even point 0003, 6min45sec observation has 0.004m horizontal and 0.002m vertical confidence.

Check all your settings and your GNSS Solutions version. Also reset your computer or receiver clock. It tells me your files were created in 2002.

Paul in PA
Modified By Lawrence Paul Lopresti on 1/14/2008 at 4:44 PM

Appreciate it ! Very big help !
This dials in my scope of investigation to office software/user messup only which REALLY helps !

Thanks !

Wayne (MotorCycleSurveyor)

This version too old ?

W

It's the latest and what I have.

Keep looking, something else has to be funky.

Paul in PA

I'm curious, did you find out where your files were set to 2002?
Ken

I had used DOS to set date to 2002 so that SiteTopo would run properly and had never set back.
I will set platform ( laptop ) date to proper and try entire process over again.

Thanks !

Don't know where to look !

Got date and time correct on laptop.
Current on version of GNSS Solutions.
Re-imported the files from PM3's.
I'm in San Diego using
USA/NAD83/California[Zone6]
Time Zone GMT-08:00 Pacific Time US & Canada & Tijuana
US Feet
Geoid 99

Everything looks good time view, survey view etc. The vectors process but all Float !

Processed all base lines and get all float solutions with 95% confidence of
about 1/2 foot ????

Ideas plese ?

Thanks

W

I would suggest creating a .SAR file and sending it to tech support. This will allow them to see all the settings your currently using in GNSS Solutions and see if they get the same results when post-processing.

Brett

Start out in WGS84, elliptical heights.

I have excellent results with your data there.

As you change your systems check and see what breaks down.

Why are you using Geoid99? I would use Geoid03. Maybe an earthquake messed your settings up?

Paul in PA
Modified By Lawrence Paul Lopresti on 1/15/2008 at 9:16 PM

Thanks for all the good ideas.

I changed settings to WGS84 with elliptical heights and got same results.

I tried un-installing Ashtech Solutions because I had both Ashtech Sol. and GNSS on same laptop and thought maybe they mess each other up.

Always same result, Float with 95% certaintly of about 1/2 foot. ?

How do I make a .SAR file ?

Wayne

Version 2.7 runs along side GNSS Solutions. In fact I had both running last night, one old project and your data.

My settings are currently
Horizontal 0.002m + 1 PPM
Vertical 0.004m + 2 PPM

Verify yours.

Then go to the "Project" pulldown

"Clear Adjustment Results"

"Clear Process Results"

Then Process and Adjust.

Paul in PA

how about the cut-off/mask angle during procrssing??

It works, day in and day out. I don't touch it until it does not work. So far I have not changed it on any GNSS project.

EOS

Paul in PA

Download a nearby CORS site and process each file from that long distance base. That will give seed coords close to geodetic truth..maybe one of your local files has a bad ecef coord in its header.

Once you have processed those sites then erase the CORS data and reprocess using the updated seed positions and see if you still get floats.

If still no joy then load one file, then one more and process. TWO files only in the project..float or fix? If fixed then add another file and reprocess.

Are occupations at same epoch rate? Antenna heights correct and type consistent? Antenna model correct?

You shouldn't be adjusting yet until you are satisfied with your vectors...adding a float vector should be a test, not a normal procedure, especially if you have bare minimum redundancy.

Wayne sent me 1 base and five remote files. I loaded them in GNSS Solutions and got very good results. The problem is to figure out what Wayne has set wrong in his Solutions. The data is OK.

Wayne just has some bad GPS karma going on in San Diego.

Paul in PA

I suspect Asthech Solutions messed up GNSS installation ?

Can we use GNSS to download PM2's and post process PN2's static & S-N-G ?

I will try un-installing GNSS, ( I have already un-installed Asht. Sol's ), then re-install GNSS and try again just using all defaults........

W

I have used GNSS Solutions to download, Z-12s, Super CAs and even an M-12. Locus being the only problem.

Since your projects are in a separate folder they should not be affected by the un-install process.

What you may want to try first is to delete everything in you particular project folder that was not downloaded directly from a receiver and open a new project in the same directory.

BTW, I did not ask before, in "Settings" have you told Solutions where to find the orbit files?

Paul in PA
Modified By Lawrence Paul Lopresti on 1/16/2008 at 6:58 PM

Ashtech Sol's has an option for this.

I don't see for GNSS ?

Still curios. Can we download PM2's with GNSS and process static and S-N-G?

Afraid I don't understand "Settings" telling GNSS where to find orbit files.

Thanks

W

Under project settings misc. there is a path setting for Precise Orbit files..........

C:\PROGRAM FILES\COMMON FILES\MAGELLAN PROFESSIONAL\ORBIT\

The only file in there is a text file stating that this is where the precise orbit files are to be.
But nothing else in there.

Should this be empty ?
What are Precise Orbit files ?
Where do we get them ?

W

I believe Precise Orbit files are from CORS sites, not if using just 2 PM3's for vectors/baselines. ?

W

I you want to use the default location you would need to put the orbits in that folder or let GS get them for you. I never did that. I get the orbits from the igs site,

http://igscb.jpl.nasa.gov/components/prods_cb.html

Then put that orbit in my particular project folder and unzip it. I have to do it for every project but I can easily see if it is there. If all the orbits were in one folder you could not tell at a glance if the one you need is not there, because the date formatting is different from observation and RINEX files. In Ashtech Solutions you got a red note that the precise orbits were not used. I do not know why GNSS Solutions does make make that useful information as evident.

igu14622_18.sp3 was the last ultra rapid orbit for Tuesday, 1/15/08, it is generally available about midnite GMT.

Name format
igu, type of orbit
1462, GPS week
2, day of week, Sunday = 0, Tuesday = 2
if instead the 8th number is 7, it means the orbit file covers the whole week.
_00, _06, _12, _18, time of day for ultra rapid orbits

igr14622.sp3 is the rapid orbit, generally available at noon EST the next day. Waiting for the rapid orbit might change you coordinates by 0.001m or so. Precise orbits come about 2 weeks later and are not worth waiting for for survey projects.

Solutions knows the file name format and will use the best available, igu, igr or igs.

In settings browse to
C:\MY PROJECTS\YOUR PROJECT FOLDER\

If you download CORS RINEX files from the ufcors site you can select and have NGS include the best available orbit.

You can also find all of them for a day at the bottom of the CORS ftp site daily folder:

ftp://www.ngs.noaa.gov/cors/rinex/2008/015/

When you download your receiver you get a broadcast orbit with your observation file.

Wayne, this should be only incremental improvement, but let's get it out of the way of the true problem.

Paul in PA

1) To un-install GNSS you just put in GNSS solutions disk and start running and it will lead you through un-install and re-installation

2) You can download PM2's with GNSS, just use option for serial port etc.

More to follow

W

Do you have a disc with the latest Solutions on it? I know I don't, I updated by downloading from the ftp site. If you uninstall, you may have to reinstall what is on your disc and update after that.

Paul in PA

Thanks .........

I re-installed. Same results.

Next I'll try loading on another laptop.

W

Go Figure !!!!!

GNSS will NOT process properly on Dell Laptop

It WILL process FIX solutions on Sony Vaio Laptop !!!!!!!!

VICTORY !!!!!!!!!

Wayne (MotorCycleSurveyor)

I have just thought of what might have been the problem. In redoing and adjusting solutions, Solutions overwrites previous files. I could not get results at one office I worked in. I had to get administrative rights. However, I would get messages from Solutions about why it could not work. In newer Windows those messages may not occur. If you are game, check what the permissions were on the Dell.

Paul in PA

Ashtech Solutions works to a fix solution.

GNSS will not process to fix.

On MY Dell.

I know other who has no problem on his Dell.

W