+Team Trail Walker Posted March 11, 2006 Share Posted March 11, 2006 I'm trying to learn more about the whole GPS system and have found a lot of good stuff on the net and this board. One thing I haven't found is a cross reference for satellite SV, PRN, Navstar numbers to the Garmin numbers I see on my GPSr. My goal is to get TLEs for the sats and know which is which. Anybody know where I can find this info? Quote Link to comment
+Sputnik 57 Posted March 11, 2006 Share Posted March 11, 2006 WAAS satellite numbers are here. There is a corralation of Space Vehicle Numbers and Psuedo-Randon Numbers (Garmin uses the latter) here (activate your pop-up blocker first). Quote Link to comment
+Team Trail Walker Posted March 11, 2006 Author Share Posted March 11, 2006 Thanks for the links! I'm one step closer to my goal. Space Track will not allow a search by SV or PRN numbers. So I still need a way to determine the "Object Identification Number" or a Navstar #. Any ideas? Thanks Quote Link to comment
+Team Trail Walker Posted March 11, 2006 Author Share Posted March 11, 2006 (edited) I think I found what I wanted. Link *Edit* Link is to outdated info, Still looking. Edited March 12, 2006 by Team Trail Walker Quote Link to comment
planewood Posted March 11, 2006 Share Posted March 11, 2006 I'm trying to learn more about the whole GPS system and have found a lot of good stuff on the net and this board. One thing I haven't found is a cross reference for satellite SV, PRN, Navstar numbers to the Garmin numbers I see on my GPSr. My goal is to get TLEs for the sats and know which is which. Anybody know where I can find this info? ORBIT SBAS SATELLITE LONGITUDE PRN Gar EGNOS Inmarsat-3-F2/AOR-E 15.5° W 120 33 Inmarsat-3-F1/IOR 64.0° E 131 44 Inmarsat-3-F5/IOR-W 25.0° E 126 39 WAAS Inmarsat-3-F4/AOR-W 54.0° W 122 35 (Being moved to 142°W) Inmarsat-3-F3/POR 178.0° E 134 47 Garmin numbers are obtained by subrtracting 87 from the PRN number. AOR-W should be at 142° west withing a couple of weeks. Don't know when it will be broadcasting corrections though. Don't know why so many are parked over the oceans?? I guess ships at sea need 3 meter accuracy. Sure wish they'd park one at 95°W. Quote Link to comment
+GOT GPS? Posted March 11, 2006 Share Posted March 11, 2006 Seems like they need a WAAS satellite at the approx longitude of W 75 degrees, to cover the eastern USA, so that the airliners do not lock onto the eastern atlantic WAAS satellite, also that position would be just east of Washington D.C. Quote Link to comment
peter Posted March 11, 2006 Share Posted March 11, 2006 Don't know why so many are parked over the oceans?? I guess ships at sea need 3 meter accuracy. Sure wish they'd park one at 95°W. The satellites they're using for SBAS (both WAAS and EGNOS flavors) weren't launched with that as their main purpose. They're using primarily existing Inmarsat birds that happen to have an available repeater channel that's suitable for use by WAAS/EGNOS. And one of the big markets for Inmarsat is to provide global communications for maritime operations. Keep in mind that the WAAS/EGNOS satellites are just acting as repeaters. The timing, ephemeris/almanac, and correction data is beamed to the WAAS/EGNOS satellite by a ground station for retransmission back to earth. Very different from the regular GPS satellites that have their own atomic clocks and initiate the data they transmit (although those also get periodic updates from ground stations). The two new satellites supporting WAAS that were launched last fall and are still undergoing testing will be more centrally located for the US. Quote Link to comment
planewood Posted March 11, 2006 Share Posted March 11, 2006 Don't know why so many are parked over the oceans?? I guess ships at sea need 3 meter accuracy. Sure wish they'd park one at 95°W. The satellites they're using for SBAS (both WAAS and EGNOS flavors) weren't launched with that as their main purpose. They're using primarily existing Inmarsat birds that happen to have an available repeater channel that's suitable for use by WAAS/EGNOS. And one of the big markets for Inmarsat is to provide global communications for maritime operations. Keep in mind that the WAAS/EGNOS satellites are just acting as repeaters. The timing, ephemeris/almanac, and correction data is beamed to the WAAS/EGNOS satellite by a ground station for retransmission back to earth. Very different from the regular GPS satellites that have their own atomic clocks and initiate the data they transmit (although those also get periodic updates from ground stations). The two new satellites supporting WAAS that were launched last fall and are still undergoing testing will be more centrally located for the US. Peter, what are these two new satellites called and where will they be parked? And, more importantly, when will they be in operation for our use?? Quote Link to comment
peter Posted March 11, 2006 Share Posted March 11, 2006 Peter, what are these two new satellites called and where will they be parked? And, more importantly, when will they be in operation for our use?? Last I heard the PanAm Galaxy15 satellite was to be positioned at W133° and the Canadian Anik F1R at W107°. So both are to the west of central but visible throughout the country (depending on horizon conditions). The Galaxy15 has already been sending valid correction and ranging data from time to time. I haven't seen the Anik yet, but my wife usually has the receiver with WAAS capability and I haven't checked recently. Quote Link to comment
+EraSeek Posted March 12, 2006 Share Posted March 12, 2006 (edited) HERE IS THE CURRENT STATUS ON ALL GPS SATS: A. BLOCK II/IIA/IIR/IIR-M INDIVIDUAL SATELLITE STATUS SVN PRN 15 15 Launched 01 OCT 1990; usable 15 OCT 1990; operating on Cs std 24 24 Launched 04 JUL 1991; usable 30 AUG 1991; operating on Cs std 25 25 Launched 23 FEB 1992; usable 24 MAR 1992; operating on Cs std 26 26 Launched 07 JUL 1992; usable 23 JUL 1992; operating on Rb std 27 27 Launched 09 SEP 1992; usable 30 SEP 1992; operating on Rb std 29 29 Launched 18 DEC 1992; usable 05 JAN 1993; operating on Rb std 30 30 Launched 12 SEP 1996; usable 01 OCT 1996; operating on Rb std 32 01 Launched 22 NOV 1992; usable 11 DEC 1992; operating on Cs std 33 03 Launched 28 MAR 1996; usable 09 APR 1996; operating on Cs std 34 04 Launched 26 OCT 1993; usable 22 NOV 1993; operating on Rb std Scheduled unusable 16 Mar 2000 UT to 17 Mar 0800 UT (NANU 2006019/9 MAR) 35 05 Launched 30 AUG 1993; usable 28 SEP 1993; operating on Cs std 36 06 Launched 10 MAR 1994; usable 28 MAR 1994; operating on Rb std 37 07 Launched 13 MAY 1993; usable 12 JUN 1993; operating on Rb std 38 08 Launched 06 NOV 1997; usable 18 DEC 1997; operating on Cs std 39 09 Launched 26 JUN 1993; usable 20 JUL 1993; operating on Cs std 40 10 Launched 16 JUL 1996; usable 15 AUG 1996; operating on Cs std 41 14 Launched 10 NOV 2000; usable 10 DEC 2000; operating on Rb std 43 13 Launched 23 JUL 1997; usable 31 JAN 1998; operating on Rb std 44 28 Launched 16 JUL 2000; usable 17 AUG 2000; operating on Rb std 45 21 Launched 31 MAR 2003; usable 12 APR 2003; operating on Rb std 46 11 Launched 07 OCT 1999; usable 03 JAN 2000; operating on Rb std 47 22 Launched 21 DEC 2003; usable 12 JAN 2004; operating on Rb std 51 20 Launched 11 MAY 2000; usable 01 JUN 2000; operating on Rb std 53 17 Launched 26 SEP 2005; usable 16 DEC 2005; operating on Rb std 54 18 Launched 30 JAN 2001; usable 15 FEB 2001; operating on Rb std 56 16 Launched 29 JAN 2003; usable 18 FEB 2003; operating on Rb std 59 19 Launched 20 MAR 2004; usable 05 APR 2004; operating on Rb std 60 23 Launched 23 JUN 2004; usable 09 JUL 2004; operating on Rb std 61 02 Launched 06 NOV 2004; usable 22 NOV 2004; operating on Rb std WAAS sat 35 is suppose to start re-broadcasting ranging on april 1. (Edit that. Here is what they say: "February 2006 – On February 1st, one of the WAAS geostationary satellites (INMARSAT AOR-W) will begin moving west to a new location. This move, which will take approximately 60 days, is the first of several steps this year leading to a new configuration of WAAS GEO satellites") Edited March 12, 2006 by EraSeek Quote Link to comment
+Team Trail Walker Posted March 12, 2006 Author Share Posted March 12, 2006 (edited) Thanks all for adding info to this thread. I made a lucky find on the net this morning, the Navstar GPS Constellation Status as of 01-02-06. In contains the information posted above plus the NORAD #s I was looking for. I should be able to download the current TLEs from Space Track now. Thanks again for the posts. Link Edited March 12, 2006 by Team Trail Walker Quote Link to comment
+fizzymagic Posted March 12, 2006 Share Posted March 12, 2006 AOR-W should be at 142° west withing a couple of weeks. Don't know when it will be broadcasting corrections though. AOR-W has been sending corrections all along. What gave you the idea that it was not? Quote Link to comment
+fizzymagic Posted March 12, 2006 Share Posted March 12, 2006 Keep in mind that the WAAS/EGNOS satellites are just acting as repeaters. The timing, ephemeris/almanac, and correction data is beamed to the WAAS/EGNOS satellite by a ground station for retransmission back to earth. Don't the WAAS satellites also send ranging data? And doesn't that require that they have clocks onboard? Quote Link to comment
+Team Trail Walker Posted March 12, 2006 Author Share Posted March 12, 2006 If anyone is interested, I put together a Satellite ID Reference Chart. Quote Link to comment
freeday Posted March 12, 2006 Share Posted March 12, 2006 cool! I was searching such kind of list a few weeks ago. Great job! Quote Link to comment
planewood Posted March 12, 2006 Share Posted March 12, 2006 If anyone is interested, I put together a Satellite ID Reference Chart. Now I'm really confused! Are what your calling PRN numbers the numbers used by Garmin? I thought you had to subtract 87 from the PRN numbers to get the Garmin numbers?? What about adding the present and known future WAAS satellites and their Garmin numbers to your chart? Is it correct that the WAAS/EGNOS satellites are/will be in a geosynchronous position over the equator? I think the one's you are showing circle the earth every 24 hrs. Here is what I'be using as reference and hence the confusion about PRN numbers. http://gpsinformation.net/exe/waas.html Quote Link to comment
peter Posted March 12, 2006 Share Posted March 12, 2006 Now I'm really confused! Are what your calling PRN numbers the numbers used by Garmin? I thought you had to subtract 87 from the PRN numbers to get the Garmin numbers?? What about adding the present and known future WAAS satellites and their Garmin numbers to your chart? Is it correct that the WAAS/EGNOS satellites are/will be in a geosynchronous position over the equator? I think the one's you are showing circle the earth every 24 hrs. Garmin subtracts 87 from the PRN numbers of the SBAS (WAAS/EGNOS/etc.) satellites which makes a nice consecutive sequence of all the PRNs. Yes, all WAAS & EGNOS satellites are in geostationary orbits (which therefore must be over the equator). The Japanese MSAS satellites are in geosynchronous but inclined orbits (so they go back and forth but at least one will always be close to overhead from Japan). The regular GPS satellites orbit once every 12 sidereal hours. But since the earth is also rotating they'll be over the same location again about every 24 hours (not exactly since the orbits are based on sidereal rather than solar time). Quote Link to comment
+Team Trail Walker Posted March 13, 2006 Author Share Posted March 13, 2006 Added WAAS & EGNOS to chart. Quote Link to comment
+geognerd Posted March 16, 2006 Share Posted March 16, 2006 Why does Garmin display a number for WAAS and EGNOS satellites, but Magellan doesn't? The eXplorists only show a W. "Magellan is teh sux0r" is not an acceptable answer. Quote Link to comment
peter Posted March 16, 2006 Share Posted March 16, 2006 Why does Garmin display a number for WAAS and EGNOS satellites, but Magellan doesn't? The eXplorists only show a W. "Magellan is teh sux0r" is not an acceptable answer. Maybe the Magellan firmware designers didn't see a need to show an identifying number. Afterall, the WAAS/EGNOS satellites are in fixed locations (current move by #122 excepted), so anyone who is really interested in the subject will probably already know which is which just by the location - and anyone who's not interested wouldn't care about the number. I'd much rather have my Garmin act in a little more intelligent way about the WAAS satellites and don't really care if it shows the numbers (it's currently constantly looking for a signal from #123 and #134, which aren't visible, and not looking for others such as #125 & #135 which are high in the sky and sending good data). Quote Link to comment
+geognerd Posted March 29, 2006 Share Posted March 29, 2006 Another topic got me thinking. How does Lowrance show WAAS satellites on the satellite screen? Does Lowrance number them like Garmin, or do they use a W like Magellan? Quote Link to comment
+DaveA Posted October 14, 2006 Share Posted October 14, 2006 Well, I just backed up my Meridian Color and then hard reset it. Left it in the driveway for a good while and then looked at it. It isn't showing all 4 WAAS sats, but it is showing 3 where it used to show only 2. I didn't have to prevent it from 'seeing' in any direction, just left it out. I assume this is because the new birds are now officially online? In any event WAAS birds high in the sky are good news. Quote Link to comment
+spotter/g Posted October 14, 2006 Share Posted October 14, 2006 Is there a chart for magellen sat #'s? thanks Quote Link to comment
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