Re: [time-nuts] GPS Common View
Hi Extracting code phase data from the TBolt may or may not be practical. I'm looking at that as a future project. Right now all I'm really trying to do is see if there is any real interest in an amateur common view experiment. With the PICTIC II and a TBolt, you *should* have just about everything you would need to do a comparison between the TBolt's 1 pps and your local standard. Not a lot of cash required since most of us seem to have TBolts already. My *guess* is that a 1 ns resolution counter is probably good enough, so the PICTIC is actually overkill. Bob On Jul 8, 2010, at 9:55 AM, b...@lysator.liu.se wrote: Many (most) GPS postprocessing packages can export a timesolution. But it is not the usual use of these packages, so it might not be the most obvious procedure. From the receiver view, the most common setup for these packages, is datasets from a dual frequency receiver, where you want to solve for a static solution or maybe a moving receiver (kinematic/ solution). Standard measurements are code and phase measurements for L1 and L2, maybe also a doppler measurement. If I remember the Thunderbolt interface discussions we had correctly there is only a code measurement available from the Tbolt. At least in the past the online services has been limited to dual frequency data and solving for a static position. There was also geografical limitations where say a US based service would not process a european dataset. Still its an interesting project to setup an amature Common view process. -- Björn Hi From a quick look it's not real clear how you would go about extracting time from the software suite. It's certainly useful for navigation though. A secondary gotcha is that the TBolt likely has some internal issues that distort the data a bit. Running a TBolt on both ends should wash out the ones that are firmware based. Bob On Jul 7, 2010, at 8:54 PM, jimlux wrote: Bob Camp wrote: Hi I just got through poking at a couple of TBolts with Lady Heather. It appears that you can indeed get the hardware and software to put the TBolt into single satellite mode. That may enable a pretty simple GPS common view setup. One way to do it: Somebody picks a set of sats and times that make sense. Since the constellation repeats it's going to be a fairly simple table of this sat / that time. At those times they run their TBolt against something pretty good and log the results The logs get put on a site somewhere Somebody else wants to do a comparison. They set up to monitor the same satellite at the same time. They log the data. They download the posted data. They run the math on the data, out comes a time comparison between the two locations. Should be fairly simple to try out. Anybody with a good house standard want to give it a try? Couldn't you run your data against Gipsy/OASIS or similar http://gipsy.jpl.nasa.gov/orms/index.html ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] GPS Common View
Hi I just got through poking at a couple of TBolts with Lady Heather. It appears that you can indeed get the hardware and software to put the TBolt into single satellite mode. That may enable a pretty simple GPS common view setup. One way to do it: Somebody picks a set of sats and times that make sense. Since the constellation repeats it's going to be a fairly simple table of this sat / that time. At those times they run their TBolt against something pretty good and log the results The logs get put on a site somewhere Somebody else wants to do a comparison. They set up to monitor the same satellite at the same time. They log the data. They download the posted data. They run the math on the data, out comes a time comparison between the two locations. Should be fairly simple to try out. Anybody with a good house standard want to give it a try? Bob ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GPS Common View
On 07/08/2010 12:49 AM, Bob Camp wrote: Hi I just got through poking at a couple of TBolts with Lady Heather. It appears that you can indeed get the hardware and software to put the TBolt into single satellite mode. That may enable a pretty simple GPS common view setup. One way to do it: Somebody picks a set of sats and times that make sense. Since the constellation repeats it's going to be a fairly simple table of this sat / that time. At those times they run their TBolt against something pretty good and log the results The logs get put on a site somewhere Somebody else wants to do a comparison. They set up to monitor the same satellite at the same time. They log the data. They download the posted data. They run the math on the data, out comes a time comparison between the two locations. Should be fairly simple to try out. You could of course agree upon 2 or more commmon view sats. As long as they are observed at the same time and in good view for both sites, it should work just as well. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GPS Common View
Hi Oddly enough I happen to be set up to do 6 common view sats Bob On Jul 7, 2010, at 6:56 PM, Magnus Danielson wrote: On 07/08/2010 12:49 AM, Bob Camp wrote: Hi I just got through poking at a couple of TBolts with Lady Heather. It appears that you can indeed get the hardware and software to put the TBolt into single satellite mode. That may enable a pretty simple GPS common view setup. One way to do it: Somebody picks a set of sats and times that make sense. Since the constellation repeats it's going to be a fairly simple table of this sat / that time. At those times they run their TBolt against something pretty good and log the results The logs get put on a site somewhere Somebody else wants to do a comparison. They set up to monitor the same satellite at the same time. They log the data. They download the posted data. They run the math on the data, out comes a time comparison between the two locations. Should be fairly simple to try out. You could of course agree upon 2 or more commmon view sats. As long as they are observed at the same time and in good view for both sites, it should work just as well. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GPS Common View
Bob Camp wrote: Hi I just got through poking at a couple of TBolts with Lady Heather. It appears that you can indeed get the hardware and software to put the TBolt into single satellite mode. That may enable a pretty simple GPS common view setup. One way to do it: Somebody picks a set of sats and times that make sense. Since the constellation repeats it's going to be a fairly simple table of this sat / that time. At those times they run their TBolt against something pretty good and log the results The logs get put on a site somewhere Somebody else wants to do a comparison. They set up to monitor the same satellite at the same time. They log the data. They download the posted data. They run the math on the data, out comes a time comparison between the two locations. Should be fairly simple to try out. Anybody with a good house standard want to give it a try? Couldn't you run your data against Gipsy/OASIS or similar http://gipsy.jpl.nasa.gov/orms/index.html ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GPS Common View
Hi From a quick look it's not real clear how you would go about extracting time from the software suite. It's certainly useful for navigation though. A secondary gotcha is that the TBolt likely has some internal issues that distort the data a bit. Running a TBolt on both ends should wash out the ones that are firmware based. Bob On Jul 7, 2010, at 8:54 PM, jimlux wrote: Bob Camp wrote: Hi I just got through poking at a couple of TBolts with Lady Heather. It appears that you can indeed get the hardware and software to put the TBolt into single satellite mode. That may enable a pretty simple GPS common view setup. One way to do it: Somebody picks a set of sats and times that make sense. Since the constellation repeats it's going to be a fairly simple table of this sat / that time. At those times they run their TBolt against something pretty good and log the results The logs get put on a site somewhere Somebody else wants to do a comparison. They set up to monitor the same satellite at the same time. They log the data. They download the posted data. They run the math on the data, out comes a time comparison between the two locations. Should be fairly simple to try out. Anybody with a good house standard want to give it a try? Couldn't you run your data against Gipsy/OASIS or similar http://gipsy.jpl.nasa.gov/orms/index.html ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GPS Common View
Bob Camp wrote: Hi From a quick look it's not real clear how you would go about extracting time from the software suite. It's certainly useful for navigation though. A secondary gotcha is that the TBolt likely has some internal issues that distort the data a bit. Running a TBolt on both ends should wash out the ones that are firmware based. Bob If you're intersted send an email to one of the guys who is involved with this. I know that they do common-view time transfer, it just might not be with that package. JPL has a bunch of groups doing this kind of stuff in the building between where I park my car and where my office is. You might also try asking the folks at http://igscb.jpl.nasa.gov/ For instance, they log raw observables of all kinds http://igscb.jpl.nasa.gov/components/data.html http://igscb.jpl.nasa.gov/components/prods.html I'll ask around tomorrow, too. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GPS Common View
Hi NIST publishes data on a per satellite basis as well. WIth all of these the big question will be weather the data is in fine enough buckets to be useful. I know that back when we had a NIST time transfer modem that they indeed had all the data to make it work. At least at that time the data they used was not available online. Of course they were indeed *selling* you the service on a monthly basis Bob On Jul 7, 2010, at 9:29 PM, jimlux wrote: Bob Camp wrote: Hi From a quick look it's not real clear how you would go about extracting time from the software suite. It's certainly useful for navigation though. A secondary gotcha is that the TBolt likely has some internal issues that distort the data a bit. Running a TBolt on both ends should wash out the ones that are firmware based. Bob If you're intersted send an email to one of the guys who is involved with this. I know that they do common-view time transfer, it just might not be with that package. JPL has a bunch of groups doing this kind of stuff in the building between where I park my car and where my office is. You might also try asking the folks at http://igscb.jpl.nasa.gov/ For instance, they log raw observables of all kinds http://igscb.jpl.nasa.gov/components/data.html http://igscb.jpl.nasa.gov/components/prods.html I'll ask around tomorrow, too. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
