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CN-122017424-A - System, device and method for calibrating and testing pulse per second in batches

CN122017424ACN 122017424 ACN122017424 ACN 122017424ACN-122017424-A

Abstract

The invention relates to the technical field of electronic measurement and test, and discloses a second pulse batch calibration test system, a second pulse batch calibration test device and a second pulse batch calibration test method, wherein the second pulse batch calibration test system comprises a main control unit positioned outside an environment test box and an internal test terminal board which are connected through a transmission wire harness; the main control unit sends a detection pulse sequence by using a pulse per second idle gap and receives feedback, and determines the phase pre-correction amount according to the calculated unidirectional physical transmission delay, thereby adjusting the pulse per second transmitting time. By monitoring the physical delay change of the transmission line bundle in real time and carrying out dynamic phase pre-correction, the transmission delay drift error caused by the temperature circulation of the environmental test box is effectively eliminated, and the pulse-per-second signal reaching the test seat is ensured to be always synchronous with the standard time with high precision.

Inventors

  • CHEN GONG

Assignees

  • 深圳市金科泰通信设备有限公司

Dates

Publication Date
20260512
Application Date
20260304

Claims (10)

  1. 1. A pulse-per-second batch calibration test system, comprising: The main control unit (200) is positioned outside the environment test box (300) and the test terminal board (400) is positioned inside the environment test box, the main control unit (200) is connected with the test terminal board (400) through a transmission wire harness (500), and the main control unit (200) is also connected with the test management host (100); The test terminal board (400) is provided with a plurality of test seats (401) and reference anchor point channels which are connected into the product to be tested in parallel; the input end of the reference anchor point channel is connected with a downlink signal link from the transmission wire harness (500), and the output end of the reference anchor point channel is connected with an uplink feedback link to the transmission wire harness (500), so that a closed loop detection circuit is formed with the main control unit (200); The main control unit (200) is used for sending a detection pulse sequence and receiving a feedback signal, determining a phase pre-correction amount according to the calculated unidirectional physical transmission delay, and controlling the second pulse signal transmission moment to realize signal synchronization at the test seat (401); the test management host (100) is used for setting parameters and acquiring frequency data of a product to be tested.
  2. 2. The pulse-per-second batch calibration testing system of claim 1, wherein said test termination board (400) is integrated with a fan-out buffer and a signal loop-back driver; The length of a wiring between the output pin of the fan-out buffer and the input pin of the signal loop-back driver is equal to the length of a wiring between the output pin of the fan-out buffer and the input pad of the test seat (401); The signal loop driver and the fan-out buffer are connected to the same voltage regulator output end and share a power supply filter capacitor, and the signal loop driver and the heat conduction pad of the fan-out buffer are connected through a grounding copper foil.
  3. 3. The second pulse batch calibration test system according to claim 1, wherein a test jig frame (310) for laminating and fixing a plurality of the test terminal boards (400) is arranged in the environment test box (300), and a circulating air duct air outlet (320) is arranged on the inner wall; The transmission harness (500) wraps the twisted pair used by the downlink signal link and the twisted pair used by the uplink feedback link in the same outer sheath cable; The shielding layer of the transmission wire harness (500) on one side of the main control unit (200) is connected with the chassis ground, and the shielding layer on one side of the test terminal board (400) is connected with the digital ground through a high-voltage-resistant safety capacitor.
  4. 4. A pulse-per-second batch calibration testing device, characterized by being applied to the pulse-per-second batch calibration testing system as claimed in any one of claims 1 to 3, comprising: the burst detection generator is used for generating a detection pulse sequence in an idle time period of an original second pulse signal and driving the detection pulse sequence to an external transmission wire harness (500) through a differential analog front-end interface; The high-precision time measurement module is used for receiving a recovery loop feedback signal through the differential analog front-end interface and measuring the time difference between the transmitting time and the receiving time of the detection pulse sequence; the central logic processing module is used for calculating the phase pre-correction deviation according to the time difference and converting the phase pre-correction deviation into a control instruction; and the digital delay line module is used for responding to the control instruction to adjust the emission delay of the original second pulse signal and outputting a synchronous second pulse signal through the differential analog front-end interface.
  5. 5. The pulse-per-second batch calibration testing device of claim 4, wherein the digital delay line module employs a hybrid architecture of coarse tuning in combination with fine tuning; The coarse adjustment utilizes a system clock counter to realize the delay of integer times of the period, and the fine adjustment utilizes a programmable delay primitive or carry chain physical transmission delay to construct a delay tap; the central logic processing module converts the phase pre-deviation correction amount into a count value and a delay progression of the digital delay line module.
  6. 6. The pulse-per-second batch calibration testing device of claim 4, wherein the central logic processing module calculates the phase pre-correction amount from the time difference by: Calculating the arithmetic average value of the time difference to obtain average round trip time; Invoking a pre-stored system static asymmetric calibration constant; and calculating the sum of half of the average round trip time and the static asymmetric calibration constant of the system to obtain the phase pre-correction amount.
  7. 7. A pulse-per-second batch calibration test method, characterized by being applied to the pulse-per-second batch calibration test system as claimed in any one of claims 1 to 3, comprising: The system is powered on and initialized, and a main control unit (200) invokes a pre-stored system static asymmetric calibration constant; The test management host (100) controls the environment test box (300) to adjust the temperature, and the main control unit (200) generates a burst detection pulse sequence by utilizing the pulse signal gap; The burst detection pulse sequence is transmitted to the test terminal board (400) through the transmission wire harness (500), and returns to the main control unit (200) through the return line after passing through the reference anchor point channel; the main control unit (200) collects the round trip time data of the burst detection pulse sequence, and calculates unidirectional physical transmission delay at the current temperature by combining the static asymmetric calibration constant of the system; the main control unit (200) determines the phase pre-correction amount according to the unidirectional physical transmission delay, and adjusts the next second pulse signal transmitting time to enable the transmitting time to advance the phase pre-correction amount relative to the standard time; the pulse signal reaches the test seat (401) through the phase pre-deviation correction second and is aligned with the standard time, and the product to be tested outputs frequency data to the test management host (100).
  8. 8. The method according to claim 7, wherein after the master control unit (200) collects the round trip time data of the burst probing pulse sequence, a statistical filtering process is further performed: the main control unit (200) collects a plurality of single round trip times corresponding to a group of continuous detection pulse sequences; the master control unit (200) eliminates the maximum value and the minimum value in the single round trip time; the main control unit (200) calculates the arithmetic average of the remaining single round trip time to obtain the average round trip time.
  9. 9. The pulse-per-second batch calibration test method of claim 7, wherein the system static asymmetry calibration constant is calibrated by: under the normal temperature environment, measuring the downlink signal link delay of the output signal of the main control unit (200) reaching the test seat (401) on the test terminal board (400) by using an external standard time measuring instrument; Measuring loop round trip delay of a signal returned to the main control unit (200) through the transmission line bundle (500) and the reference anchor point channel; Calculating a difference between the downlink signal link delay and half of the loop round trip delay, and taking the difference as the system static asymmetry calibration constant.
  10. 10. The method for calibrating and testing the second pulse batch according to claim 7, wherein after the product to be tested outputs the frequency data to the test management host (100), the following steps are performed: receiving the frequency observation value uploaded by the main control unit (200), and calculating a frequency deviation value according to the nominal frequency of the product to be detected; comparing the frequency deviation value with a preset qualification judgment threshold interval to generate a frequency temperature characteristic curve; And calculating a compensation coefficient according to the frequency temperature characteristic curve, and writing the compensation coefficient into a product to be tested.

Description

System, device and method for calibrating and testing pulse per second in batches Technical Field The invention relates to the technical field of electronic measurement and test, in particular to a system, a device and a method for calibrating and testing pulse per second in batches. Background In the production process of the high-precision time-frequency product, strict frequency-temperature characteristic test is required to be carried out so as to calibrate the stability of the output frequency of the high-precision time-frequency product under different temperature environments. The common test scheme is that a batch of products to be tested are placed inside an environmental test box, a high-precision test management host and a main control unit are placed outside the environmental test box, and the high-precision test management host and the main control unit are connected through a transmission wire harness penetrating through the wall of the box. In the test process, the external main control unit needs to send a second pulse signal to the internal product to be tested through the transmission line bundle, and the second pulse signal is used as a synchronous reference standard for calibrating the frequency of the product to be tested or performing phase comparison. In practical wide temperature range cyclic tests, the temperature inside the environmental test chamber can undergo a wide range of changes from extremely low temperatures to extremely high temperatures. The transmission wire harness connecting the main control unit and the product to be tested is used as a physical medium for signal transmission, and the dielectric constant of the insulating layer, the physical length and the resistivity of the conductor are affected by temperature change, so that the propagation speed of the signal in the transmission wire harness is changed. This means that the physical transmission delay of the pulse-per-second signal from the outside to the inside product to be measured is not a constant value but exhibits a dynamic drift characteristic with temperature fluctuation as the temperature in the environmental test chamber rises and falls. The existing batch test system generally adopts a static compensation mode, namely, the delay value of a primary transmission wire harness is measured in a normal temperature environment and is used as a fixed deduction item in the subsequent whole test process. This approach ignores the effects of delayed thermal drift of the transmission line bundle in a variable temperature environment. When the environment test box is at the high-low temperature extreme point, non-negligible deviation can be generated between the actual transmission delay and the preset static delay value, so that the phase of the second pulse signal reaching the port of the product to be tested cannot be strictly synchronous with the standard time. The synchronization error can be directly introduced into frequency measurement data of a product to be tested, influences the accuracy of the finally calculated frequency compensation parameter, and is difficult to meet the requirement of a high-stability time-frequency device on nanosecond or even higher-precision synchronization test. Disclosure of Invention The invention aims to provide a second pulse batch calibration test system, a second pulse batch calibration test device and a second pulse batch calibration test method, which solve the problem that a second pulse signal reaching a test terminal plate cannot maintain high-precision phase synchronization due to physical transmission delay drift of a long-distance transmission wire harness caused by environmental temperature change when an environmental test box is used for carrying out batch frequency temperature characteristic test. In order to achieve the above purpose, the invention is realized by the following technical scheme: the second pulse batch calibration test system, device and method comprise the following steps: The invention provides a second pulse batch calibration test system, which mainly solves the problem of transmission delay drift during synchronous frequency test of multiple products to be tested in an environmental test box. The system comprises a main control unit positioned outside an environment test box and a test terminal board positioned inside the environment test box, wherein the main control unit is connected with the test terminal board through a transmission wire harness, and is simultaneously in communication connection with a test management host. The test terminal board is provided with a plurality of test seats for accessing the product to be tested in parallel and a reference anchor point channel which is not connected with the product to be tested. And the input end of the reference anchor point channel is connected with a downlink signal link from the transmission wire harness, the output end of the reference anchor point channel is connected with an uplin