[time-nuts] Ashtech 3DF GPS
On more or less of a whim, I found and bought an Ashtech 3DF GPS. The interesting thing about this particular GPS is that it uses four separate GPS antennas mounted in a diamond pattern about 1 meter on a side and can compute not only the usual stuff, but also heading, roll, and pitch angles. I had heard of this being possible, but never actually seen it done. There are no accessories included with this unit, other than the power cord. Does anyone know where I can find a manual for it? Will this GPS work with just four ordinary active antennas or are the antennas special? Given the complexity of the additional data massaging it does to extract the angular data, does this also mean that it will have more accurate position and or timing performance? Does it need all four antennas to be able to do anything at all, or can it compute position and time with just one antenna connected? Thanks, Stan ___ 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] Ashtech 3DF GPS
According to this: cedb.asce.org/cgi/WWWdisplay.cgi?80010 it seems that this GPS uses carrier phase tracking... it seems interesting. On Tue, May 1, 2012 at 3:08 PM, Stan swp...@earthlink.net wrote: On more or less of a whim, I found and bought an Ashtech 3DF GPS. The interesting thing about this particular GPS is that it uses four separate GPS antennas mounted in a diamond pattern about 1 meter on a side and can compute not only the usual stuff, but also heading, roll, and pitch angles. I had heard of this being possible, but never actually seen it done. There are no accessories included with this unit, other than the power cord. Does anyone know where I can find a manual for it? Will this GPS work with just four ordinary active antennas or are the antennas special? Given the complexity of the additional data massaging it does to extract the angular data, does this also mean that it will have more accurate position and or timing performance? Does it need all four antennas to be able to do anything at all, or can it compute position and time with just one antenna connected? Thanks, Stan ___ 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] Ashtech 3DF GPS
Hi Stan, On more or less of a whim, I found and bought an Ashtech 3DF GPS. The interesting thing about this particular GPS is that it uses four separate GPS antennas mounted in a diamond pattern about 1 meter on a side and can compute not only the usual stuff, but also heading, roll, and pitch angles. I had heard of this being possible, but never actually seen it done. There are no accessories included with this unit, other than the power cord. Does anyone know where I can find a manual for it? Look for manuals in ftp://ftp.ashtech.com/OEM,%20Sensor%20%20ADU/ perhaps it is this one? Or an earlier version. ftp://ftp.ashtech.com/OEM,%20Sensor%20%20ADU/ADU2/Reference%20Material/adu2.pdf Will this GPS work with just four ordinary active antennas or are the antennas special? Will probably work with almost any antenna, but for good performance use a geodetic quality rover antenna. Given the complexity of the additional data massaging it does to extract the angular data, does this also mean that it will have more accurate position and or timing performance? No, its specialty is to determine the relative positions of the four antennas. This will give heading, roll and pitch of the vehicle the system is mounted on. Does it need all four antennas to be able to do anything at all, or can it compute position and time with just one antenna connected? It will probably do position and time with just the master antenna connected. Thanks, Stan Good luck! -- Björn ___ 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] Ashtech 3DF GPS
These are specifically for attitude determination in mobile environments. Not sure how good they would be for timing though. I remember seeing something from Trimble a few years back which did similar. Rob K -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Stan Sent: 01 May 2012 14:08 To: time-nuts@febo.com Subject: [time-nuts] Ashtech 3DF GPS On more or less of a whim, I found and bought an Ashtech 3DF GPS. The interesting thing about this particular GPS is that it uses four separate GPS antennas mounted in a diamond pattern about 1 meter on a side and can compute not only the usual stuff, but also heading, roll, and pitch angles. I had heard of this being possible, but never actually seen it done. There are no accessories included with this unit, other than the power cord. Does anyone know where I can find a manual for it? Will this GPS work with just four ordinary active antennas or are the antennas special? Given the complexity of the additional data massaging it does to extract the angular data, does this also mean that it will have more accurate position and or timing performance? Does it need all four antennas to be able to do anything at all, or can it compute position and time with just one antenna connected? Thanks, Stan ___ 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.
