Systems and methods for transmitting time-frequency signals in optical fibers

Abstract

The invention discloses a system and method for transmitting time-frequency signals in an optical fiber, wherein the system for transmitting time-frequency signals in an optical fiber includes: a transmitting end for modulating a time-frequency signal to be transmitted into a modulation signal, and converting the time-frequency signal into a modulation signal The modulated signal is sent, and the time-frequency signal to be transmitted includes a second pulse signal and a frequency signal; the receiving end is used to receive and demodulate the modulated signal sent by the transmitting end, and process the demodulated signal to obtain time-frequency signal. The invention mixes and modulates the second pulse signal and the frequency signal into one signal for transmission, which saves optical fiber wavelength resources, and transmits the second pulse signal and the frequency signal at the same time, and the channel consistency is good.

Description

technical field [0001] The invention belongs to the fields of time service, navigation and communication, in particular to a system and method for transmitting time-frequency signals in optical fibers. Background technique [0002] Since optical fiber has been widely deployed at present, and optical fiber has the characteristics of good anti-interference and low loss, it is suitable for long-distance transmission. Therefore, the use of optical fiber for time and frequency transmission is a research hotspot at home and abroad. [0003] Using optical fiber to transmit time and frequency actually needs to transmit the following information: [0004] (1) second pulse; [0005] (2) frequency; [0006] (3) The current time, such as which day and which second; [0007] (4) Management, control, alarm and maintenance information. [0008] In the prior art, three wavelengths or four wavelengths in an optical fiber are generally used for transmission, wherein one wavelength is used...

AI Technical Summary

Problems solved by technology

That is, the existing technology adopts the method of separately transmitting the second pulse, frequency signal and time management control information. This method has very obvious disadvantages: the second pulse and frequency transmission are difficult to align, not only the two signals at the transmitting end are difficult to align , and different wavelengths experience different channel conditions in the transmission process, and different transmission delays may occur

Sometimes the rising or falling edge of the second pulse is easily distorted during transmission, thus blurring the rising or falling edge of the second pulse, resulting in time transmission errors

[0010] In addition, the existing technology often uses the direct transmission of the basic frequency, such as the frequency of 10MHz or 100MHz, the second pulse directly transmits this pulse or performs modulation after spread spectrum, and the transmission accuracy is not very high

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