The effect of link noise correction method based on weighted average of noise in the fiber optic temperature delay ripple
The signal transmission delay of the optical fiber time-frequency transfer link fluctuates with the change of temperature,and its fluctuation amplitude increases with the increase of optical fiber link length and temperature change range.For noise with reciprocating fluctuation characteristics in time-frequency transfer links,the weighted average method of the total noise of inter-station clock difference of remote atomic clocks shows good calibration effect in satellite systems.The amplitude of temperature delay fluctuations in ultra-long distance optical fiber time-frequency transfer links far exceeds that of the space-ground communication link of satellite system.The calibration effect of this method on the reciprocating fluctuation noise at the level of optical fiber temperature delay fluctuation is still uncertain.The simulation results based on the hydrogen atomic clock show that this method has good calibration effect on the temperature delay fluctuation of optical fiber.Under the simulated temperature delay fluctuation of 1,000 kilometers,when the time keeping stations at both ends of the optical fiber have 12 hydrogen atomic clocks each,the calibration residual is around 1ns.The difference in frequency stability between the cross-station clock after calibration and the atomic clock is two orders of magnitude lower than the frequency stability of the atomic clock.When the time keeping stations at both ends of the optical fiber have 400 cesium atomic clocks each,the calibration residual is around 10ns.Due to the significant difference in noise between hydrogen atomic clocks and cesium atomic clocks,it's difficult to achieve joint calculation of hydrogen and cesium atomic clocks.
NETL
NSTL
万方数据
