High-precision 1PPS time service signal time delay adjusting device

Abstract

The invention discloses a high-precision 1PPS time service signal time delay adjusting device, and relates to the technical field of time unification. A constant-temperature crystal oscillator unit is used for generating a 10M sine wave signal and sending the 10M sine wave signal to a high-speed comparator; the MCU unit is used for generating a coarse adjustment 1PPS signal and sending the coarse adjustment 1PPS signal to the D trigger beating unit, the MCU unit further comprises a DAC module, and the DAC module is used for outputting a high-precision adjustable control voltage to the high-speed comparator; the high-speed comparator is used for comparing the 10M sine wave signal with the control voltage, generating a 10M phase-shifted square wave which has the same frequency with the 10M sine wave signal and is adjustable in phase, and sending the 10M phase-shifted square wave to the D trigger beating unit; and the D trigger beating unit is used for beating the 10M phase shift square wave and the coarse adjustment 1PPS signal and outputting a high-precision time-delay-adjustable target 1PPS signal to external equipment. According to the invention, not only is a high-precision time delay adjustment function realized, but also the problem of immediate inconsistency when the 1PPS reaches the standby time service equipment end in the use environment of different cable lengths of the equipment is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of time unification, and in particular to a high-precision 1PPS timing signal delay adjustment device. Background Art

[0002] At present, the industry's demand for time accuracy is getting higher and higher. While meeting the requirements of high-precision timing, it is also necessary to ensure that the second pulse moments received by each user end are highly consistent. Due to inconsistent cable lengths, the delay in receiving the 1PPS signal is also inconsistent. It is difficult to ensure that the final output 1PPS can meet the required accuracy. This requires the timing equipment to have the function of high-precision delay adjustment. Summary of the Invention

[0003] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a high-precision 1PPS timing signal delay adjustment device to solve the problem of instant inconsistency in the 1PPS arrival at the backup timing device end when the existing time unification field equipment is used in an environment with different cable lengths.

[0004] The object of the present invention is achieved through the following technical solutions: A high-precision 1PPS timing signal delay adjustment device includes a constant temperature crystal oscillator unit, a high-speed comparator, an MCU unit and a D-flip-flop beat unit; The constant temperature crystal oscillator unit is used to generate a 10M sine wave signal and send the 10M sine wave signal to the high-speed comparator; The MCU unit is used to generate a coarse adjustment 1PPS signal and send it to the D-type flip-flop beat unit. The MCU unit also includes a DAC module, which is used to output a high-precision adjustable control voltage to the high-speed comparator. The high-speed comparator is used to compare the 10M sine wave signal and the control voltage, generate a 10M phase-shifted square wave with the same frequency and adjustable phase as the 10M sine wave signal, and send the 10M phase-shifted square wave to the D-type flip-flop beat unit; The D-type flip-flop beat unit is used to beat the 10M phase-shifted square wave and the coarse adjustment 1PPS signal, and output a target 1PPS signal with high-precision adjustable delay to an external device.

[0005] Furthermore, the specific process of comparing the 10M sinusoidal wave signal and the control voltage to generate a 10M phase-shifted square wave with the same frequency and adjustable phase as the 10M sinusoidal wave signal is as follows: Compare the amplitude of the 10M sinusoidal wave signal with the control voltage. If the amplitude of the 10M sinusoidal wave signal is smaller than the control voltage, the corresponding generated 10M phase-shifted square wave is a low level. If the amplitude of the 10M sinusoidal wave signal is larger than the control voltage, the corresponding generated 10M phase-shifted square wave is a high level, so that the phase difference between the 10M phase-shifted square wave and the 10M sinusoidal wave signal is ±90°.

[0006] Furthermore, the specific process of beating the 10M phase-shifted square wave and the coarse adjustment 1PPS signal is as follows: The rising edge of the 10M phase-shifted square wave is detected within the high-level time period of the coarse-adjustment 1PPS signal. Before the rising edge of the 10M phase-shifted square wave is detected, the target 1PPS signal is generated as a low level. When the rising edge of the 10M phase-shifted square wave is detected, the target 1PPS signal is set to a high level until the falling edge of the coarse-adjustment 1PPS signal is detected, and then the target 1PPS signal is set to a low level, so that the rising edge of the target 1PPS signal is consistent with the rising edge of the 10M phase-shifted square wave, and the falling edge is consistent with the falling edge of the coarse-adjustment 1PPS signal.

[0007] Furthermore, the delay adjustment device further includes a time difference measurement unit, which is externally connected to a standard 1PPS signal and is connected to the D-type flip-flop beat unit and the MCU unit. The target 1PPS signal generated by the D-type flip-flop beat unit is also sent to the time difference measurement unit as a fine-tuning 1PPS signal. The time difference measurement unit is used to measure the time difference between the externally connected standard 1PPS signal and the fine-tuning 1PPS signal sent by the D-flip-flop beat unit, obtain the time interval value and send it to the MCU unit.

[0008] Furthermore, the specific process of the MCU unit generating the coarse adjustment 1PPS signal is as follows: The MCU unit first generates an initial coarse adjustment 1PPS signal with a rising edge at a random time, and then adjusts the rising edge of the initial coarse adjustment 1PPS signal according to the received time interval value, so that the rising edge of the initial coarse adjustment 1PPS signal is aligned with the rising edge of the externally connected standard 1PPS signal to obtain a coarse adjustment 1PPS signal.

[0009] Furthermore, the MCU unit adopts STM32 or GigaDevice's GD32 series.

[0010] The beneficial effects of the present invention are: The present invention adopts the DAC of the MCU to output a high-precision adjustable voltage, which is compared with the 10M sine wave output by the constant temperature crystal oscillator to generate a square wave with the same frequency and adjustable phase. The square wave is then used to beat with the 1PPS output by the MCU, thereby obtaining a 1PPS adjustable at any position. At the same time, the 1PPS is controlled by the 10M square wave. The present invention not only realizes the function of high-precision delay adjustment of 1PPS, so that the adjustable accuracy theoretically reaches 1ps, but also solves the problem of instant inconsistency of 1PPS arriving at the backup timing device end when the existing equipment in the field of time unification is used in environments with different cable lengths. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 A block diagram of the logical composition of a delay adjustment device corresponding to an embodiment; Figure 2 A schematic diagram of a high-speed comparator outputting a 10M phase-shifted square wave; Figure 3 A schematic diagram of the D-type flip-flop beat unit outputting the target 1PPS signal; Figure 4 A schematic diagram of generating a coarse 1PPS signal for the MCU unit. DETAILED DESCRIPTION

[0012] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the embodiments. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work shall fall within the scope of protection of the present invention.

[0013] See Figures 1-4 , the present invention provides a technical solution: A high-precision 1PPS timing signal delay adjustment device comprises a constant temperature crystal oscillator unit, a high-speed comparator, an MCU unit and a D-flip-flop beat unit.

[0014] like Figure 1As shown, the present embodiment provides a high-precision 1PPS timing signal delay adjustment device including a constant temperature crystal oscillator unit, a high-speed comparator, an MCU unit, a D-type flip-flop beat unit and a time difference measurement unit; wherein, the constant temperature crystal oscillator unit is specifically configured as an OCXO constant temperature crystal oscillator, the MCU unit is equipped with a DAC module, the MCU unit adopts STM32 or the domestic GigaDevice GD32 series, and the D-type flip-flop beat unit includes a D-type flip-flop. The OCXO constant temperature crystal oscillator is connected to the high-speed comparator, the MCU unit is connected to the high-speed comparator, the D-type flip-flop beat unit and the time difference measurement unit, and the D-type flip-flop beat unit is also connected to the high-speed comparator and the time difference measurement unit. The time difference measurement unit is externally connected to a standard 1PPS signal, and the output of the D-type flip-flop beat unit is connected to an external corresponding user terminal device, outputting a 1PPS timing signal with the required delay and high precision to the corresponding user terminal.

[0015] The constant temperature crystal oscillator unit is used to generate a 10M sine wave signal and send the 10M sine wave signal to the high-speed comparator; The MCU unit is used to generate a coarse adjustment 1PPS signal and send it to the D-type flip-flop beat unit. The specific process of generating the coarse adjustment 1PPS signal is as follows: like Figure 4 As shown in the figure, the specific process of the MCU unit generating the coarse adjustment 1PPS signal is as follows: The MCU first generates an initial coarse-tuned 1PPS signal with a rising edge at a random time. It then adjusts the rising edge of the initial coarse-tuned 1PPS signal based on the received time interval to align it with the rising edge of an externally connected standard 1PPS signal, resulting in a coarse-tuned 1PPS signal. The coarse-tuned 1PPS signal initially consists of a pulse with a rising edge at a random time. The TDC measures the time difference between the coarse-tuned 1PPS and the external 1PPS. Based on this measured time difference, the phase of the coarse-tuned 1PPS is adjusted to align it substantially with the phase of the external reference 1PPS.

[0016] The MCU unit also includes a DAC module, which is used to output a high-precision adjustable control voltage to the high-speed comparator. The specific process of outputting a high-precision adjustable control voltage is as follows: the corresponding PID parameter list is pre-established within the MCU unit, the corresponding loop bandwidth control parameters are preset, and the suitability of the loop bandwidth is intelligently determined based on the changes in the voltage control data during the taming process, the tracking lock phase, and the time parameters, and the loop bandwidth is automatically increased or decreased. Through the incremental PID control algorithm, a high-precision taming function is achieved, the impact of taming on the stability of the local oscillator is reduced, and the time source tracking taming function is realized. The incremental PID algorithm formula is as follows:

[0017] In the above formula, Indicates the difference this time, Indicates the last difference, K P , K I , K D They represent the proportional, integral, and differential control coefficients respectively, and Δpwm represents the voltage control adjustment increment.

[0018] The high-speed comparator is used to compare the 10M sinusoidal wave signal with the control voltage to generate a 10M phase-shifted square wave with the same frequency and adjustable phase as the 10M sinusoidal wave signal, and send the 10M phase-shifted square wave to the D-type flip-flop beat unit. The specific process of comparing the 10M sinusoidal wave signal with the control voltage to generate a 10M phase-shifted square wave with the same frequency and adjustable phase as the 10M sinusoidal wave signal is as follows: Compare the amplitude of the 10M sinusoidal wave signal with the control voltage. If the amplitude of the 10M sinusoidal wave signal is smaller than the control voltage, the corresponding generated 10M phase-shifted square wave is a low level. If the amplitude of the 10M sinusoidal wave signal is larger than the control voltage, the corresponding generated 10M phase-shifted square wave is a high level, so that the phase difference between the 10M phase-shifted square wave and the 10M sinusoidal wave signal is ±90°.

[0019] In some specific embodiments, the process of comparing the 10M sine wave signal and the control voltage is as follows: Figure 2 As shown, the voltage amplitude of the 10M sine wave signal is (j, i). Therefore, the value of the control voltage b is within the range of (j, i). The control voltage b and the 10M sine wave a are processed by the comparator to generate a 10M phase-shifted square wave c. The phase difference between the 10M phase-shifted square wave c and the 10M phase-shifted sine wave a is ±90° (i.e., one-half clock cycle), which is converted into a time of ±25ns. According to the existing DAC control algorithm, the existing 12-bit DAC of the MCU is upgraded to 16 bits, which means that 50ns can be split into 65536 parts, which can be adjusted to an equivalent of 0.76ps after conversion.

[0020] The D-type flip-flop beat unit is used to beat the 10M phase-shifted square wave and the coarse-tuning 1PPS signal, and output a target 1PPS signal with high-precision adjustable delay to an external device. The specific process of beating the 10M phase-shifted square wave and the coarse-tuning 1PPS signal is as follows: detecting the rising edge of the 10M phase-shifted square wave within the high-level time period of the coarse-tuning 1PPS signal, generating a target 1PPS signal at a low level before detecting the rising edge of the 10M phase-shifted square wave, setting the target 1PPS signal to a high level when detecting the rising edge of the 10M phase-shifted square wave, and setting the target 1PPS signal to a low level until detecting the falling edge of the coarse-tuning 1PPS signal, so that the rising edge of the target 1PPS signal is consistent with the rising edge of the 10M phase-shifted square wave, and the falling edge is consistent with the falling edge of the coarse-tuning 1PPS signal.

[0021] In a specific embodiment, the specific process of the above-mentioned tapping is as follows: Figure 3 As shown in the figure, the coarsely adjusted 1PPS signal m beats the phase-adjustable 10M phase-shifted square wave signal p. The resulting 1PPS signal n coincides with the rising edge of the 10M phase-shifted square wave p. This effectively controls the 1PPS signal to the 10M phase-shifted square wave, enabling high-precision 1PPS delay adjustment, allowing both delay and advance. This results in highly accurate 1PPS delay adjustment technology with an accuracy exceeding 1ps.

[0022] The delay adjustment device also includes a time difference measurement unit, which is externally connected to a standard 1PPS signal and is connected to the D-type flip-flop beat unit and the MCU unit. The target 1PPS signal generated by the D-type flip-flop beat unit is also sent to the time difference measurement unit as a fine-tuning 1PPS signal. The time difference measurement unit is used to measure the time difference between the externally connected standard 1PPS signal and the fine-tuning 1PPS signal sent by the D-flip-flop beat unit, obtain the time interval value and send it to the MCU unit.

[0023] The present invention adopts the DAC of the MCU to output a high-precision adjustable voltage, which is compared with the 10M sine wave output by the constant temperature crystal oscillator to generate a square wave with the same frequency and adjustable phase. The square wave is then used to beat with the 1PPS output by the MCU, thereby obtaining a 1PPS adjustable at any position. At the same time, the 1PPS is controlled by the 10M square wave. The present invention not only realizes the function of high-precision delay adjustment of 1PPS, so that the adjustable accuracy theoretically reaches 1ps, but also solves the problem of instant inconsistency of 1PPS arriving at the backup timing device end when the existing equipment in the field of time unification is used in environments with different cable lengths.

[0024] The foregoing description is merely a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein and should not be construed as excluding other embodiments. Rather, the present invention can be used in various other combinations, modifications, and environments and can be modified within the scope of the concept described herein through the above teachings or techniques or knowledge in the relevant field. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention are intended to be protected by the appended claims.

Claims

1. A high-precision 1PPS timing signal delay adjustment device, characterized by: Including constant temperature crystal oscillator unit, high-speed comparator, MCU unit and D flip-flop beat unit; The constant temperature crystal oscillator unit is used to generate a 10M sine wave signal and send the 10M sine wave signal to the high-speed comparator; The MCU unit is used to generate a coarse adjustment 1PPS signal and send it to the D-type flip-flop beat unit. The MCU unit also includes a DAC module, which is used to output a high-precision adjustable control voltage to the high-speed comparator. The high-speed comparator is used to compare the 10M sine wave signal and the control voltage, generate a 10M phase-shifted square wave with the same frequency and adjustable phase as the 10M sine wave signal, and send the 10M phase-shifted square wave to the D-type flip-flop beat unit; The D-type flip-flop beat unit is used to beat the 10M phase-shifted square wave and the coarse adjustment 1PPS signal, and output a target 1PPS signal with high-precision adjustable delay to an external device.

2. A high-precision 1PPS timing signal delay adjustment device according to claim 1, characterized in that: The specific process of comparing the 10M sine wave signal and the control voltage to generate a 10M phase-shifted square wave with the same frequency and adjustable phase as the 10M sine wave signal is as follows: Compare the amplitude of the 10M sinusoidal wave signal with the control voltage. If the amplitude of the 10M sinusoidal wave signal is smaller than the control voltage, the corresponding generated 10M phase-shifted square wave is a low level. If the amplitude of the 10M sinusoidal wave signal is larger than the control voltage, the corresponding generated 10M phase-shifted square wave is a high level, so that the phase difference between the 10M phase-shifted square wave and the 10M sinusoidal wave signal is ±90°.

3. A high-precision 1PPS timing signal delay adjustment device according to claim 1, characterized in that: The specific process of beating the 10M phase-shifted square wave and the coarse-tuned 1PPS signal is as follows: The rising edge of the 10M phase-shifted square wave is detected within the high-level time period of the coarse-adjustment 1PPS signal. Before the rising edge of the 10M phase-shifted square wave is detected, the target 1PPS signal is generated as a low level. When the rising edge of the 10M phase-shifted square wave is detected, the target 1PPS signal is set to a high level until the falling edge of the coarse-adjustment 1PPS signal is detected, and then the target 1PPS signal is set to a low level, so that the rising edge of the target 1PPS signal is consistent with the rising edge of the 10M phase-shifted square wave, and the falling edge is consistent with the falling edge of the coarse-adjustment 1PPS signal.

4. A high-precision 1PPS timing signal delay adjustment device according to claim 1, characterized in that: The delay adjustment device also includes a time difference measurement unit, which is externally connected to a standard 1PPS signal and is connected to the D-type flip-flop beat unit and the MCU unit. The target 1PPS signal generated by the D-type flip-flop beat unit is also sent to the time difference measurement unit as a fine-tuning 1PPS signal. The time difference measurement unit is used to measure the time difference between the externally connected standard 1PPS signal and the fine-tuning 1PPS signal sent by the D-flip-flop beat unit, obtain the time interval value and send it to the MCU unit.

5. A high-precision 1PPS timing signal delay adjustment device according to claim 4, characterized in that: The specific process of the MCU unit generating the coarse adjustment 1PPS signal is as follows: The MCU unit first generates an initial coarse adjustment 1PPS signal with a rising edge at a random time, and then adjusts the rising edge of the initial coarse adjustment 1PPS signal according to the received time interval value, so that the rising edge of the initial coarse adjustment 1PPS signal is aligned with the rising edge of the externally connected standard 1PPS signal to obtain a coarse adjustment 1PPS signal.

6. A high-precision 1PPS timing signal delay adjustment device according to claim 1, characterized in that: The MCU unit adopts STM32 or GigaDevice's GD32 series.

Images