Compensator and method for transmission delay in optical fiber time-frequency transmission

Abstract

The invention discloses a compensator and method for transmission time delay in optical fiber time-frequency transmission. The compensator includes a central station and a remote station connected by optical fiber. The central station includes a time-frequency standard source, frequency multiplier Ⅰ, frequency multiplier Ⅱ, filter Ⅰ, mixer Ⅰ, mixer Ⅱ, filter Ⅱ , Optical Transmitter Module I, Multiplexer, Optical Receiver Module I and Amplifier I, the remote station includes demultiplexer, optical modulator I, optical modulator II, optical receiver module II, amplifier II, filter III, phase shifter device, power divider, optical module II and electrical interface. The mechanism of the method is as follows: the central station performs remote injection locking on the photoelectric oscillator of the remote station, and the remote station reversely transmits the error accumulation to the central station, and the central station uses a phase delay and fluctuation control circuit to compensate, so that the photoelectric oscillator of the remote station The output of the oscillator is locked to the central station. The invention eliminates the asymmetry of two-way time delay, makes the transmission accuracy not limited by the measurement accuracy of the system, and can carry out long-distance accurate transmission.

Description

technical field [0001] The invention relates to the technical field of transmission time delay compensation in optical fiber transmission, in particular to a compensator and method for transmission time delay in optical fiber time-frequency transmission. Background technique [0002] Time frequency is the basic physical quantity of matter existence and the basis of people's daily life, production and scientific research. The transmission of time-frequency reference signals includes the foreign GPS / GLONASS multi-source time synchronization-based space-based time-frequency network and the domestic "Beidou" second-generation satellite positioning and navigation system. In general, the space-based time-frequency system can achieve time synchronization accuracy on the order of nanoseconds and 10 -15 Frequency transfer stability per day. However, when the time and frequency of higher-precision clock sources (such as ion clocks, fountain clocks, and optical clocks) need to be tra...

AI Technical Summary

Problems solved by technology

The well-connected optical cable network provides a mature physical path for time-frequency signal transmission. The optical network built on the physical network can be used as a reference time synchronization network, but its original design purpose is to serve communication services, so its accuracy Affected by the network greatly, the time synchronization accuracy can only reach the order of hundreds of nanoseconds

But its disadvantage is that the assumption of round-trip and return delays is not easy to meet due to the existence of fiber dispersion when the same link uses different wavelengths, the error of compensation Δθ at the sending end is large, and the two-way time delay is asymmetrical, which makes the transmission accuracy of time-frequency signal optical fiber transmission low, and The output of the photoelectric oscillator at the remote station cannot be synchronized with the central station, and long-distance transmission cannot be realized

Images