Carrier-phase time transfer

摘要

We have conducted several time-transfer experiments using thenphase of the GPS carrier rather than the code, as is done in currentnGPS-based time-transfer systems. Atomic clocks were connected tongeodetic GPS receivers; we then used the GPS carrier-phase observationsnto estimate relative clock behavior at 6-minute intervals. GPSncarrier-phase time transfer is more than an order of magnitude morenprecise than GPS common view time transfer and agrees, within thenexperimental uncertainty, with two-way satellite time-transfernmeasurements for a 2400 km baseline. GPS carrier-phase time transfer hasna stability of 100 ps, which translates into a frequency uncertainty ofnabout two parts in 10-15 for an average time of 1 day