Title :
Earth station errors in two-way time and frequency transfer
Author :
Ascarrunz, Franklin G. ; Jefferts, S.R. ; Parker, Thomas E.
Author_Institution :
Time & Frequency Div., Nat. Inst. of Stand. & Technol., Boulder, CO, USA
fDate :
4/1/1997 12:00:00 AM
Abstract :
We have investigated the earth station errors in two-way time transfer. A 3.7-m earth station and a very small aperture terminal earth station were used in these experiments along with a transponder located on a mountain about 10 km away. The temperature coefficient of the receive delay for the 3.7 m NIST earth station was (-150±30) ps/K, and the temperature coefficient for the transmit delay was (-50±10) ps/K. The overall temperature coefficient for the earth station was (100±30) ps/K. Aside from environmental errors there are apparent changes in delay due to characteristics of the modulation/demodulation scheme. Apparent delay changes due to nonlinearity effects in the earth station were as high as 10 ns. The errors due to code dependence and third code interference were sometimes as high as 3 ns
Keywords :
coding errors; delays; error analysis; measurement standards; modulation; satellite ground stations; spread spectrum communication; time measurement; transponders; 10 km; 3.7 m; NIST earth station; apparent delay changes; code dependence; earth station errors; environmental errors; modulation/demodulation scheme; nonlinearity effects; path nonreciprocity; spread spectrum modulation scheme; temperature coefficient of receive delay; temperature coefficient of transmit delay; third code interference; transponder; two-way frequency transfer; two-way time transfer; very small aperture terminal earth station; Apertures; Clocks; Delay effects; Demodulation; Frequency; NIST; Satellite ground stations; Temperature dependence; Temperature measurement; Transponders;
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on
