On Jun 30, 2006, at 3:20 PM, Magnus Danielson wrote:
From: "Stephan Sandenbergh" <[EMAIL PROTECTED]>Subject: [time-nuts] Relationship of relative stability between distant locations using GPS and environmental factorsDate: Fri, 30 Jun 2006 14:36:30 +0200 Message-ID: <[EMAIL PROTECTED]>Hi,Hi Stephan,A number of recent entries to this list have mentioned topics relating to GPS timing and environmental corrupting factors (e.g. Ionosphere, Temp., Humidity, etc.). Personally, I am very interested in setting up a very precise relative time between locations (maybe 100s of meters to 10s ofkilometres apart) on time scales of (maybe 100s of seconds to 10s ofminutes). I noted some members referred to dual frequency receivers for overcoming these effects. Can anyone point me to some literature, articlesor links to overcome these environmental factors?I can recommend the "Global Positioning System: Theory and Application - Volume I" and also (naturally) Volume II, edited by Parkinson & Spilker. The pair should be a natural extention to the "Understanding GPS Principlesand Applications" edited by Kaplan.
Also, note that you don't really need dual-frequency for short baseline synchronization. Common-view carrier phase time transfer is designed for exactly that situation. The ionospheric problems that dual frequency is designed to overcome are roughly equal when the two receivers are sitting that close, so you're able to get sub- nanosecond synchronization.
Environmental effects and system calibration (antenna length, etc) will be your big problems. There's been lots of good discussion about heat/humidity/etc., and clocks on this list. The usual solution for the national timing labs (and tvb. :) is to stick everything in a completely controlled room. :-)
-Dave
PGP.sig
Description: This is a digitally signed message part
_______________________________________________ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
