An optical fiber-based high-precision clock signal forwarding system device

Abstract

The present application discloses a high-precision clock signal forwarding system based on optical fiber, which includes a GPS / Beidou satellite signal receiving antenna, a timing signal forwarding device, an optical signal transmission device, and a timing signal receiving and analyzing device; the GPS / Beidou satellite signal receiving antenna is used to receive the GPS / Beidou clock signal and send it to the timing signal forwarding device; the timing signal forwarding device is used to analyze the input clock signal from the GPS / Beidou satellite signal receiving antenna to generate a clock signal and a pulse signal, and then convert them into optical signals and send them to the optical signal transmission device according to different rules and send them to the timing signal receiving and analyzing device; the timing signal receiving and analyzing device is used to restore the received optical signal to generate a clock signal and a pulse signal, and perform calibration to generate accurate clock information and send it to the terminal. It realizes the accurate forwarding of GPS / Beidou clock information and completes the forwarding of GPS / Beidou satellite clock signals with high precision and long transmission distance.

Description

Technical Field

[0001] This application relates to the field of engineering communication technology, and more specifically, to a high-precision clock signal forwarding system device based on optical fiber. Background Art

[0002] At present, with the continuous high-speed development of the national economy, the era of automation, digitization, and networking in all walks of life has arrived. Processors and network devices provide a better platform for data exchange, analysis, and application among various control information systems. However, at the same time, the good cooperation of each platform requires precise control of the respective timings of each sub-component in the system. In practical applications, people mainly rely on the timing information provided by GPS / Beidou satellites for time synchronization. In traditional cable GPS / Beidou signal forwarding systems, the devices adopt the GPS / Beidou signal transmission, GPS / Beidou chip parsing, and forwarding mode. Since the transmission speeds of GPS / Beidou signals of different GPS / Beidou satellites in the GPS / Beidou antenna are the same, the GPS / Beidou chip can ignore the signal error brought by the transmission cable of the GPS / Beidou antenna during parsing;

[0003] However, with the vigorous development of China's infrastructure construction, the application environments of many automation platforms have changed greatly, and many scenarios where GPS / Beidou satellite signals cannot be directly received and applied have emerged, such as long railway tunnels, underground buildings, underwater buildings, etc. In the past, we often directly installed the GPS / Beidou antenna in the outdoor environment not far from the application scenario, and then connected the electrical signal received by the GPS / Beidou antenna to the terminal in the application scenario using coaxial cables. However, the transmission attenuation of coaxial cables can only maintain the signal transmission stability for about 50 meters at most. Even if facilities such as amplifiers are added in the middle of the coaxial cable, the signal transmission stability can only be maintained for about 200 meters at most. The signal transmission stability of about 200 meters can no longer meet the application scenarios of long railway and highway tunnels. At the same time, as the transmission distance lengthens, GPS / Beidou satellite signals can no longer be directly transmitted through cables. Therefore, there is an urgent need for a GPS / Beidou satellite clock signal forwarding device with a longer signal transmission distance. Summary of the Invention

[0004] In view of at least one defect or improvement requirement of the prior art, the present invention provides a high-precision clock signal forwarding system device based on optical fiber, which greatly extends the forwarding distance of GPS / Beidou timing signals, and the application accuracy reaches the nanosecond level, realizing precise long-distance forwarding of GPS / Beidou clock information.

[0005] To achieve the above object, according to the first aspect of the present invention, there is provided an optical fiber-based high-precision clock signal forwarding system device, which is suitable for accurately forwarding GPS / Beidou clock information over a long distance. It is characterized by including a GPS / Beidou satellite signal receiving antenna, a timing signal forwarding device, an optical signal transmission device, and a timing signal receiving and analyzing device;

[0006] The GPS / Beidou satellite signal receiving antenna is used to receive GPS / Beidou clock signals and send them to the timing signal forwarding device;

[0007] The timing signal forwarding device is used to analyze the GPS / Beidou clock information input from the GPS / Beidou satellite signal receiving antenna to generate a clock signal and a pulse signal, and then convert them into optical signals and send them to the optical signal transmission device according to different rules;

[0008] The optical signal transmission device is used to receive the optical signal and send it to the timing signal receiving and analyzing device;

[0009] The timing signal receiving and analyzing device is used to restore the received optical signal to generate a clock signal and a pulse signal, and perform calibration to generate accurate clock information and send it to the terminal.

[0010] Further, the timing signal forwarding device includes a forwarding central processor, a temperature-compensated crystal oscillator, and a GPS / Beidou chip;

[0011] The GPS / Beidou chip is used to obtain GPS / Beidou clock information and send it to the forwarding central processor; the forwarding central processor is used to receive and process the GPS / Beidou clock information to obtain clock data, and convert the time data into an optical signal; the temperature-compensated crystal oscillator receives the instruction signal from the forwarding central processor, calculates the crystal oscillator data and sends it to the forwarding central processor for calculating the clock information.

[0012] Further, the forwarding central processor includes a signal receiving and processing module and a digital-optical conversion module; among them,

[0013] The signal receiving and processing module is used to receive GPS / Beidou clock information, analyze and generate a square wave pulse and a time signal, and send the square wave pulse and the time signal to the digital-optical conversion module according to different sending rules;

[0014] The digital-optical conversion module is used to receive the square wave pulse and the time signal, and convert them into optical signals and send them to the optical signal transmission device respectively.

[0015] Further, the signal receiving and processing module sending the square wave pulse and the time signal to the digital-optical conversion module by different sending strategies includes:

[0016] The signal receiving and processing module obtains the total number of crystal oscillator counts in the first period of the waveform cycle at the rising edge of the waveform cycle of the square wave pulse, generates current clock information by obtaining the total number of crystal oscillator counts in the first period of the first cycle and the total number of crystal oscillator counts in the first period of the second cycle; and sends the total number of crystal oscillator counts in the first period of the second cycle and the current clock information to the digital optoelectronic conversion module;

[0017] The digital optoelectronic conversion module receives the total number of crystal oscillator counts in the first period of the second cycle and the current clock information, converts them into optical signals and sends them to the optical signal forwarding device;

[0018] After receiving the reply signal, the signal receiving and processing module obtains the total number of crystal oscillator counts in the second period of the second cycle and sends it to the timing signal receiving and analyzing device.

[0019] Further, the timing signal receiving and analyzing device includes a restoration central processor and a temperature-compensated crystal oscillator;

[0020] The restoration central processor is used to restore and calibrate the received clock information, and the clock information includes square wave pulses and time signals;

[0021] The temperature-compensated crystal oscillator receives the indication signal from the restoration central processor, calculates the crystal oscillator data and sends it to the restoration central processor, and the start time of calculating the clock information is when the restoration central processor generates the square wave pulse.

[0022] Further, the restoration central processor includes a digital optoelectronic conversion module, a square wave pulse receiving and restoration module, a square wave pulse correction module, a time signal restoration module and a time signal correction module; among them,

[0023] The digital optoelectronic conversion module is used to receive the optical signal sent by the optical signal transmission device and convert it into a clock signal, the clock signal includes crystal oscillator information, and sends it to the square wave pulse receiving and restoration module and the time signal restoration module;

[0024] The square wave pulse receiving and restoration module obtains the clock signal, generates a square wave pulse and records the square wave pulse crystal oscillator information and sends it to the square wave pulse correction module;

[0025] The square wave pulse correction module is used to obtain the square wave pulse crystal oscillator information and perform real-time verification and correction on the square wave pulse interval;

[0026] The time signal restoration module obtains the clock signal and records the clock signal crystal oscillator information and sends it to the time signal correction module;

[0027] The time signal correction module performs real-time verification on the transmitted time information by obtaining the clock signal crystal oscillator information.

[0028] Further, the square wave pulse receiving and restoring module obtains a clock signal to generate a square wave pulse and records oscillator information and sends it to the square wave pulse correction module, including:

[0029] The square wave pulse receiving and restoring module obtains the total number of first oscillator counts in the second period to generate a square wave pulse in the second period. When generating a square wave pulse in the third period, it obtains the total number of first oscillator counts in the third period through a temperature-compensated crystal oscillator and sends it to the square wave pulse correction module.

[0030] Further, the time signal restoring module obtains a clock signal and records oscillator information and sends it to the time signal correction module; including:

[0031] When the time signal restoring module receives the current clock information, it sends a reply signal to the timing signal forwarding device and starts counting through a temperature-compensated crystal oscillator magnet. When the total number of second oscillator counts in the third period meets a predetermined condition, it obtains the total number of second oscillator counts in the third period and sends and sends the clock information of the next second with the current time information incremented by one to the terminal.

[0032] Further, the time signal correction module performs real-time verification of the transmitted time information by obtaining oscillator information, including:

[0033] The time signal correction module performs real-time verification of the transmitted time information by obtaining the total number of second oscillator counts in the third period that meets a preset condition.

[0034] Further, the preset condition is satisfied:

[0035] (CNT11 / CNT1) * 3 / 2 + CNT12 / CNT2 = 1

[0036] Wherein, CNT1 is the total number of first oscillator counts in the second period; CNT11 is the second oscillator count in the second period; CNT2 is the total number of first oscillator counts in the third period; CNT11 is the second oscillator count in the third period.

[0037] Generally speaking, compared with the prior art, the above technical solution conceived by the present invention can achieve the following beneficial effects:

[0038] (1) The high-precision clock signal forwarding system device based on optical fiber provided by the present invention analyzes the clock signal received by the GPS / Beidou satellite signal receiving antenna through the timing signal forwarding device to generate a clock signal and a pulse signal, and then converts them into optical signals and sends them to the optical signal transmission device according to different rules and sends them to the timing signal receiving and analyzing device; through the low-attenuation characteristic of optical fiber transmission, the forwarding distance of the GPS / Beidou timing signal is effectively extended. The timing signal receiving and analyzing device is used to restore the received optical signal to generate a clock signal and a pulse signal, and perform calibration to generate accurate clock information and send it to the terminal, thus completing the forwarding of the GPS / Beidou satellite clock signal with high precision and long transmission distance.

[0039] (2) By adopting the high-precision clock signal forwarding system device based on optical fiber provided by the present invention, through combining counting such as timing, time synchronization, clock calibration, and clock restoration, accurate forwarding of GPS / Beidou clock information is realized, and the application accuracy reaches the nanosecond level. Brief Description of the Drawings

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0041] Figure 1 It is a schematic structural diagram of a high-precision clock signal forwarding system device based on optical fiber provided by an embodiment of the present application;

[0042] Figure 2 It is a schematic structural diagram of the timing signal forwarding device provided by an embodiment of the present application;

[0043] Figure 3 It is a schematic structural diagram of the forwarding center processor provided by an embodiment of the present application;

[0044] Figure 4 It is a schematic structural diagram of the timing signal receiving and analyzing device provided by an embodiment of the present application;

[0045] Figure 5 It is a logical schematic diagram of the period of crystal oscillator counting provided by an embodiment of the present application.

[0046] Figure 6 It is a schematic structural diagram of the restoration center processor provided by an embodiment of the present application. Detailed Embodiments

[0047] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0048] The terms "first", "second", "third", etc. in the description and claims of this application and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally further includes steps or units not listed, or optionally further includes other steps or units inherent to these processes, methods, products or devices.

[0049] In scenarios where GPS / Beidou satellite signals cannot be directly received and applied, such as long railway tunnels, underground buildings, underwater buildings, etc., traditional communication means cannot avoid problems such as unstable signal transmission caused by excessive distance and large clock signal errors in forwarding.

[0050] The inventors of this application have found through research that the GPS / Beidou antenna is directly installed in an outdoor environment not far from the application scenario, and then the electrical signals received by the GPS / Beidou antenna are connected to the terminal in the application scenario through a coaxial cable. However, the transmission attenuation of the coaxial cable can only maintain the signal transmission stability of about 50 meters at most. Even if facilities such as amplifiers are added in the middle of the coaxial cable, the signal transmission stability can only be maintained at about 200 meters at most. The signal transmission stability of about 200 meters can no longer meet the application scenarios of long railway and highway tunnels. In addition, if the GPS / Beidou information is digitized and directly applied for optical data transmission, the clock chip is obtained by locally applying the GPS / Beidou chip, and the clock information is directly digitized and transmitted to the lower-level terminal, then the time delay of optical fiber transmission is ignored, and the application accuracy is in milliseconds, which is only applicable to occasions with low application accuracy.

[0051] As Figure 1 shown, a high-precision clock signal forwarding system device proposed in this solution proposes a complete technical solution by discovering the essence of the above problems. Specifically, the high-precision clock signal forwarding system of this solution includes a GPS / Beidou satellite signal receiving antenna, a timing signal forwarding device, an optical signal transmission device, and a timing signal receiving and analyzing device.

[0052] The GPS / Beidou satellite signal receiving antenna is used to receive GPS / Beidou clock information and send it to the timing signal forwarding device; the timing signal forwarding device is used to analyze the GPS / Beidou clock information input from the GPS / Beidou satellite signal receiving antenna to generate a clock signal and a pulse signal, and then convert them into optical signals and send them to the optical signal transmission device according to different rules; the optical fiber communication system is used to receive the optical signal and send it to the timing signal receiving and analyzing device; the timing signal receiving and analyzing device is used to restore the received optical signal to generate a clock signal and a pulse signal, and perform calibration to generate accurate clock information and send it to the terminal.

[0053] Specifically, in a preferred embodiment, as Figure 2 shown, the timing signal forwarding device includes a forwarding central processor, a temperature-compensated crystal oscillator, and a GPS / Beidou chip. The GPS / Beidou chip obtains GPS / Beidou clock information and sends it to the forwarding central processor; among them, the GPS / Beidou chip receives the clock message regularly transmitted by the GPS / Beidou satellite, and then corrects the clock message transmitted by the GPS / Beidou satellite by applying the delay difference caused by the different transmission distances of different satellites to obtain accurate GPS / Beidou clock information. Correcting the clock message transmitted by the GPS satellite belongs to the basic principle of GPS / Beidou timing and will not be elaborated here.

[0054] Preferably, an FPGA is used as the forwarding central processor. The FPGA obtains clock data by receiving and processing GPS / Beidou clock information, and converts the time data into an optical signal and sends it to the optical signal transmission device; as Figure 3 shown, preferably, the forwarding central processor includes a signal receiving and processing module and a digital-optical conversion module; the signal receiving and processing module receives the GPS / Beidou clock information, analyzes and generates a square wave pulse and a time signal, and sends the square wave pulse and the time signal to the digital-optical conversion module by using different sending strategies; the digital-optical conversion module receives the square wave pulse and the time signal, and converts them into optical signals respectively and sends them to the optical fiber through an optical interface.

[0055] Preferably, the temperature-compensated crystal oscillator receives the indication signal from the forwarding central processor, calculates the crystal oscillator data and sends it to the forwarding central processor; specifically, when the forwarding central processor generates a square wave pulse, it sends a counting signal to the temperature-compensated crystal oscillator, and the temperature-compensated crystal oscillator starts to record the crystal oscillator information.

[0056] Square wave pulse signal forwarding rule: The forwarding signal receiving and processing module obtains the total crystal oscillator count by sending indication information to the temperature-compensated crystal oscillator at the rising edge of the waveform period of the square wave pulse f; as Figure 5As shown, for example, it can be to obtain the total number of crystal oscillator counts CNT0 of the first square wave pulse period and the total number of crystal oscillator counts CNT1 of the second square wave pulse period, and calculate and generate the current clock information T1. Specifically, the clock information forwarding rule is: T1 = CNT1 / CNT0, where this is the accuracy below seconds; the forwarding signal receiving and processing module sends the obtained total number of crystal oscillator counts CNT1 of the second period and the current clock information T1 to the digital optoelectronic conversion module as pseudo time signals respectively.

[0057] The digital optoelectronic conversion module receives the total number of crystal oscillator counts CNT1 of the second period and the current clock information T1, converts them into optical signals and sends them to the optical fiber. Of course, other optical signal forwarding devices can also be used, which are not limited in this solution.

[0058] In addition, after the signal receiving and processing module receives the reply signal sent by the timing signal receiving and analyzing device after receiving the current time signal, it obtains the total number of crystal oscillator counts of the second period of the second crystal oscillator by sending indication information to the temperature-compensated crystal oscillator, and sends it to the timing signal receiving and analyzing device.

[0059] The timing signal receiving and analyzing device receives the optical signal sent by the optical fiber; specifically, in a preferred embodiment, as Figure 4 shown, the timing signal receiving and analyzing device includes a reduction central processor and a temperature-compensated crystal oscillator.

[0060] Preferably, an FPGA is used as the reduction central processor to restore the received optical signal to clock information, calibrate the received clock information, and the clock information includes square wave pulses and time signals, and forge the clock information in the GPS mode and transmit it to the device.

[0061] Preferably, the temperature-compensated crystal oscillator receives the indication signal from the reduction central processor, calculates the crystal oscillator data and sends it to the reduction central processor, and the start time for calculating the clock information is when the reduction central processor generates a square wave pulse.

[0062] As Figure 6 shown, preferably, the reduction central processor includes a digital optoelectronic conversion module, a square wave pulse receiving and restoring module, a square wave pulse correction module, a time signal restoring module, and a time signal correction module; among them,

[0063] The digital optoelectronic conversion module receives the optical signal sent by the optical signal transmission device and converts it into clock information, and the clock information includes crystal oscillator information and time signals; the digital optoelectronic conversion module sends the clock signal to the square wave pulse receiving and restoring module and the time signal restoring module.

[0064] Preferably, for the restoration of the square wave pulse signal: when the square wave pulse receiving and restoring module obtains the clock signal, it generates a square wave pulse and obtains the total number of oscillator counts from the temperature-compensated crystal oscillator at the rising edge of the waveform period of the square wave pulse f and sends it to the square wave pulse correction module; for example, as Figure 5 shown, when it obtains the total number of first oscillator counts CNT1 in the second period, it generates a square wave pulse and starts counting through the temperature-compensated crystal oscillator. When generating the square wave pulse in the next period, it obtains the total number of first oscillator counts CNT2 in the third period through the temperature-compensated crystal oscillator, resets the count of the temperature-compensated crystal oscillator at the same time, and sends the total number of first oscillator counts CNT1 in the second period and the total number of first oscillator counts CNT2 in the third period to the square wave pulse correction module.

[0065] Preferably, the square wave pulse correction module obtains the first oscillator count information of adjacent square wave pulse periods to real-time verify and correct the square wave pulse interval.

[0066] Preferably, for the restoration of the time signal: after calibrating the communication delay through the time correction module, the real clock signal is sent to the terminal. The time signal restoration module obtains the clock signal and records the oscillator information of the clock signal and sends it to the time signal correction module; for example, when the time signal restoration module receives the current clock information, it sends a reply message to the time service signal forwarding device and starts counting through the temperature-compensated crystal magnet. When the second oscillator count CNT12 in the third period meets the predetermined condition, it obtains the total number of the second oscillator counts CNT12 in the third period and sends the clock information of the next second with the current time information plus one to the terminal.

[0067] Specifically, as an embodiment, the predetermined condition is (CNT11 / CNT1)*3 / 2 + CNT12 / CNT2 = 1,

[0068] wherein, CNT1 is the total number of first oscillator counts in the second period; CNT11 is the second oscillator count in the second period; CNT2 is the total number of first oscillator counts in the third period; CNT11 is the second oscillator count in the third period.

[0069] Preferably, the time signal correction module obtains the oscillator information of the clock signal to real-time verify the transmitted time information.

[0070] Through the above method, after digitizing the GPS / Beidou information and dividing it into a clock signal and a pulse signal and converting them into an optical signal, by setting different rules for transmission, combined with counting such as time service, time alignment, clock verification, and clock restoration, it realizes the precise forwarding of GPS / Beidou clock information, with an application accuracy reaching the nanosecond level, and combined with the optical signal forwarding device, it further completes the forwarding of GPS / Beidou satellite clock signals with high precision and long transmission distance.

[0071] It should be noted that, for the foregoing method embodiments, for the sake of simple description, they are all expressed as a series of action combinations. However, those skilled in the art should be aware that this application is not limited by the described action sequence, because according to this application, certain steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily essential to this application.

[0072] In the above embodiments, the descriptions of the respective embodiments have their own emphases. For the parts not detailed in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0073] In the several embodiments provided by this application, it should be understood that the disclosed device can be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the division of the units is only a logical function division. In actual implementation, there can be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections to each other can be through some service interfaces. The indirect coupling or communication connection of the device or unit can be in an electrical or other form.

[0074] The units described as separate components may or may not be physically separated. The components displayed as units may or may not be physical units, that is, they can be located in one place, or they can be distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0075] In addition, in each embodiment of this application, the functional units can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit. The above integrated units can be implemented in the form of hardware or in the form of software functional units.

[0076] When the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable memory. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a memory and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned memory includes: various media such as USB flash drives, read-only memory (ROM), random access memory (RAM), external hard drives, magnetic disks, or optical discs that can store program codes.

[0077] Those of ordinary skill in the art can understand that all or part of the steps in the various methods of the above embodiments can be completed by instructing relevant hardware through a program. This program can be stored in a computer-readable memory, and the memory can include: flash drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical discs, etc.

[0078] The above are only exemplary embodiments of the present disclosure, and the scope of the present disclosure cannot be limited thereby. That is, any equivalent changes and modifications made in accordance with the teachings of the present disclosure still fall within the scope covered by the present disclosure. Those skilled in the art will readily think of other implementations of the present disclosure after considering the specification and practicing the present disclosure herein. This application aims to cover any variations, uses, or adaptive changes of the present disclosure, and these variations, uses, or adaptive changes follow the general principles of the present disclosure and include common general knowledge or conventional technical means in the technical field not recorded in the present disclosure. The specification and embodiments are only regarded as exemplary, and the scope and spirit of the present disclosure are defined by the claims.

[0079] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as within the scope described in this specification.

[0080] Those skilled in the art can easily understand that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A high-precision clock signal forwarding system based on optical fiber, characterized in that It includes a GPS / Beidou satellite signal receiving antenna, a timing signal forwarding device, an optical signal transmission device, and a timing signal receiving and analyzing device; among them, The GPS / Beidou satellite signal receiving antenna is used to receive GPS / Beidou clock signals and send them to the timing signal forwarding device; The timing signal forwarding device is used to analyze the GPS / Beidou clock information input from the GPS / Beidou satellite signal receiving antenna to generate a clock signal and a pulse signal, and then convert them into optical signals and send them to the optical signal transmission device according to different rules; the timing signal forwarding device includes a forwarding central processor, a temperature-compensated crystal oscillator, and a GPS / Beidou chip; The forwarding central processor includes a signal receiving and processing module and a digital-optical conversion module; among them, The signal receiving and processing module is used to receive GPS / Beidou clock information, analyze and generate a square wave pulse and a time signal, and send the square wave pulse and the time signal to the digital-optical conversion module according to different sending rules; the digital-optical conversion module is used to receive the square wave pulse and the time signal and convert them into optical signals and send them to the optical signal transmission device; Among them, the signal receiving and processing module obtains the total number of crystal oscillator counts of the waveform period at the rising edge of the waveform period of the square wave pulse, generates the current clock information by obtaining the total number of crystal oscillator counts of the first period and the total number of crystal oscillator counts of the second period; and sends the total number of crystal oscillator counts of the second period and the current clock information to the digital-optical conversion module; at the same time, after the signal receiving and processing module receives the reply signal sent by the timing signal receiving and analyzing device, it obtains the total number of crystal oscillator counts of the second period of the second period and sends it to the digital-optical conversion module; the optical signal transmission device is used to receive the optical signal and send it to the timing signal receiving and analyzing device; The timing signal receiving and analyzing device is used to restore the received optical signal to generate a clock signal and a pulse signal, and perform calibration to generate accurate clock information and send it to the terminal.

2. The high-precision clock signal forwarding system based on optical fiber according to claim 1, wherein, The timing signal forwarding device includes a forwarding central processor, a temperature-compensated crystal oscillator, and a GPS / Beidou chip; among them, The GPS / Beidou chip is used to obtain GPS / Beidou clock information and send it to the forwarding central processor; the forwarding central processor is used to receive and process the GPS / Beidou clock information to obtain clock data, and convert the time data into an optical signal; the temperature-compensated crystal oscillator receives the indication signal of the forwarding central processor, calculates the crystal oscillator data and sends it to the forwarding central processor for calculating the clock information.

3. A high-precision clock signal forwarding system based on optical fiber according to claim 1, wherein, The timing signal receiving and analyzing device includes a restoration central processor and a temperature-compensated crystal oscillator; The restoration central processor is used to restore and calibrate the received clock information, and the clock information includes a square wave pulse and a time signal; The temperature-compensated crystal oscillator receives the indication signal of the restoration central processor, calculates the crystal oscillator data and sends it to the restoration central processor, and the start time of calculating the crystal oscillator data is when the restoration central processor generates a square wave pulse.

4. A high-precision clock signal forwarding system based on optical fiber according to claim 3, wherein, The reduction central processor includes a digital optoelectronic conversion module, a square wave pulse receiving and restoring module, a square wave pulse correction module, a time signal restoring module, and a time signal correction module; wherein, The digital optoelectronic conversion module is configured to receive the optical signal sent by the optical signal transmission device and convert it into a clock signal, and send it to the square wave pulse receiving and restoring module and the time signal restoring module, and the clock signal includes crystal oscillator information; The square wave pulse receiving and restoring module obtains the clock signal to generate a square wave pulse, and records the square wave pulse crystal oscillator information and sends it to the square wave pulse correction module; The square wave pulse correction module is used to obtain the square wave pulse crystal oscillator information to real-time verify and correct the square wave pulse interval; The time signal restoring module obtains the clock signal and records the clock signal crystal oscillator information and sends it to the time signal correction module; The time signal correction module real-time verifies the transmitted time information by obtaining the clock signal crystal oscillator information.

5. The high-precision clock signal forwarding system based on optical fiber according to claim 4, wherein, The square wave pulse receiving and restoring module obtains the clock signal to generate a square wave pulse and records the crystal oscillator information and sends it to the square wave pulse correction module includes: The square wave pulse receiving and restoring module obtains the total number of first crystal oscillator counts in the second period to generate a square wave pulse in the second period, and obtains the total number of first crystal oscillator counts in the third period through a temperature-compensated crystal oscillator when generating the square wave pulse in the third period, and sends it to the square wave pulse correction module.

6. A high-precision clock signal forwarding system based on optical fiber according to claim 4, wherein, The time signal restoring module obtains the clock signal and records the crystal oscillator information and sends it to the time signal correction module; includes: When the time signal restoring module receives the current clock information, it sends a reply signal to the timing signal forwarding device, and starts counting through a temperature-compensated crystal magnet. When the total number of second crystal oscillator counts in the third period meets a predetermined condition, it obtains the total number of second crystal oscillator counts in the third period and sends the next second clock information with the current time information incremented by one to the terminal.

7. A high-precision clock signal forwarding system based on optical fiber according to claim 4, wherein, The time signal correction module real-time verifies the transmitted time information by obtaining the crystal oscillator information includes: The time signal correction module real-time verifies the transmitted time information by obtaining the total number of second crystal oscillator counts in the third period that meets the preset conditions.

8. A high-precision clock signal forwarding system based on optical fiber according to claim 7, wherein, The preset conditions are satisfied: (CNT11 / CNT1)*3 / 2 + CNT12 / CNT2 = 1 Wherein, CNT1 is the total number of first crystal oscillator counts in the second period; CNT11 is the second crystal oscillator count in the second period; CNT2 is the total number of first crystal oscillator counts in the third period; CNT12 is the second crystal oscillator count in the third period.

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