A time comparison equipment test evaluation method based on Beidou comparison reference error

Abstract

The present application relates to high-precision time comparison equipment performance test technical field, specifically discloses a kind of time comparison equipment test evaluation method based on Beidou comparison reference error, comprising the following steps: step one, calibrating receiver, step two, line delay is calibrated, step three, time comparison, step four, according to the index and the relationship of Beidou reference precision comparison precision evaluation;The present application uses flexible, high-precision Beidou receiver as time comparison reference, the time comparison reference equipment of two receivers of Beidou is respectively with the two stations of the measured time comparison equipment Time comparison test is carried out simultaneously with clock source, the time comparison precision of the measured time comparison equipment can be obtained by the difference between the two, and according to whether the time comparison reference precision of Beidou comparison reference can reach three times of the measured time comparison equipment index as limit, evaluate the measured time comparison equipment according to the situation, guarantee the characteristics such as high precision, equipment light of evaluation method.

Description

Technical Field

[0001] This invention belongs to the technical field of performance testing of high-precision time comparison equipment, specifically involving a test evaluation method for time comparison equipment based on the BeiDou comparison benchmark error. Background Technology

[0002] Time references are fundamental to the operation of human society and economic sectors, especially high-tech sectors, such as communications, transportation, and electricity. To maintain time consistency, high-precision time comparison technologies and equipment are needed to ensure time uniformity in different geographically distant regions. Currently, time comparison technologies that can be used over long distances include satellite two-way time comparison technology and GNSS common-view time comparison technology. At present, the accuracy of GNSS two-way time comparison can reach less than 1 ns at a distance of 100 km, and the accuracy can reach less than 5 ns at a distance of 3000 km. The accuracy of satellite common-view time comparison can also reach less than 2 ns.

[0003] To evaluate the accuracy of newly developed time comparison equipment, it was previously necessary to use a benchmark device with a time comparison accuracy one order of magnitude higher, or at least three times higher. Currently, newly developed time comparison equipment uses similar technologies, and its accuracy is comparable to existing equipment. Therefore, evaluating the time comparison accuracy of newly developed equipment with accuracy indicators essentially equivalent to existing benchmark equipment is a challenge. Furthermore, the flexibility, small size, and light weight of these devices make them unsuitable for various time comparison scenarios and facilities, hindering convenient, objective, and accurate evaluation of the time comparison performance of the tested equipment. Summary of the Invention

[0004] The purpose of this invention is to provide a time comparison equipment test evaluation method based on BeiDou comparison benchmark error, so as to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A test evaluation method for time comparison equipment based on BeiDou comparison benchmark error includes the following steps:

[0007] Step 1: Calibrate the BeiDou comparison reference receivers A1 and A2 at a qualified calibration center. The time comparison accuracy of A1 and A2 at a specific length baseline is d. 基准 ;

[0008] Step 2: Using the 10MHz frequency signal and 1PPS signal output by the time comparison station E as time-frequency reference 1, the Beidou comparison reference receiver A1 and the B1 station in the time comparison equipment under test are both connected to time-frequency reference 1 to calibrate the time delay of each line.

[0009] Step 3: Using the 10MHz frequency signal and 1PPS signal output by the clock of time comparison station F as time and frequency reference 2, the Beidou comparison reference receiver A2 and station B2 in the time comparison equipment under test are connected to time and frequency reference 2 to calibrate the delay of each link.

[0010] Step 4: The time comparison link consisting of the time comparison equipment B1 and B2 performs time comparison, and the time comparison link consisting of the Beidou comparison reference receivers A1 and A2 performs time comparison synchronously.

[0011] Step 5: Conduct continuous testing for no less than 7 days and record the clock difference measurement results of the time comparison equipment B1 and B2 and the Beidou comparison reference receivers A1 and A2.

[0012] Step 6: Calculate the time comparison accuracy d (ns) between the time comparison equipment B1 and B2 using the following formula 1):

[0013]

[0014] In the formula: x T,i —The measured time is compared with the i-th clock difference measurement result of equipment B1 and B2;

[0015] x B,i —The i-th clock difference measurement result of Beidou comparison reference receivers A1 and A2;

[0016] n—Number of valid measurement results;

[0017] Step 7: Determine if it is qualified.

[0018] Preferably, the determination in step seven is as follows: if the time comparison reference accuracy d of Beidou comparison reference receivers A1 and A2 is... 基准 The time required to compare the test results with the equipment's B1 and B2 indicators should not be less than the time required to complete the test. 指标 3 times, that is Then when d≤d 指标 If the time comparison accuracy of the tested time comparison equipment B1 and B2 meets the index requirements, it is considered qualified; otherwise, it is considered unqualified. If the time comparison accuracy of the Beidou comparison reference receiver A1 and A2 is d... 基准 The time difference between the tested equipment and the B1 and B2 indicators d is lower than the test time. 指标 3 times, that is Then when If the time comparison accuracy of the time comparison equipment B1 and B2 meets the index requirements, it is considered qualified; otherwise, it is considered unqualified.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] Using a flexible and high-precision BeiDou receiver as a time comparison benchmark, two receivers of the BeiDou time comparison benchmark equipment are simultaneously compared with two clock sources of the time comparison equipment under test. The difference between the two results yields the time comparison accuracy of the time comparison equipment under test. The time comparison equipment is evaluated based on whether the accuracy of the BeiDou time comparison benchmark reaches three times the performance index of the time comparison equipment under test. If the accuracy of the BeiDou time comparison benchmark reaches three times the performance index of the time comparison equipment under test, the comparison accuracy result is directly compared with the performance index of the time comparison equipment under test. Otherwise, according to the error propagation law, the benchmark accuracy (error) of the BeiDou time comparison equipment must be taken into account and evaluated together with the performance index of the time comparison equipment under test to determine whether the time comparison accuracy of the time comparison equipment meets the standard. This method ensures high accuracy, lightweight and compact equipment, and flexible use, making it suitable for various time comparison scenarios and facilities. It can conveniently, objectively, and accurately evaluate the time comparison performance of the time comparison equipment under test. Attached Figure Description

[0021] Figure 1 This is a test scenario diagram when the time comparison equipment under test in Embodiment 1 of the present invention is a GNSS satellite common-view or precise single-point positioning time comparison equipment. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Example 1:

[0024] Please see Figure 1 As shown, a test evaluation method for time comparison equipment based on BeiDou comparison benchmark error is presented, wherein;

[0025] Baseline 1, consisting of time and frequency center stations M and N, has a length of 2850km. The aim is to evaluate the performance of a pair of GNSS satellite co-view time comparison equipment between stations M and N under long baseline conditions. Its time comparison accuracy within a baseline length of 3000km is 5ns. The following is a test and evaluation of the comparison accuracy of this pair of test satellite co-view time comparison equipment.

[0026] The specific steps are as follows:

[0027] Step 1: A qualified calibration center calibrates the BeiDou comparison reference receivers A1 and A2. After calibration, the time comparison accuracy of the BeiDou comparison reference receivers A1 and A2 within a 3000km baseline length is 2.3ns.

[0028] Step 2: At the time and frequency center station M, the Beidou comparison reference receiver A1 and the GNSS satellite common-view comparison device B1 are respectively connected to the 10MHz frequency signal and 1PPS signal output by the time and frequency output reference point 1 of station M, and the line delay between A1 and B1 connected to the time and frequency output reference point 1 is accurately measured and calibrated.

[0029] Step 3: At the time and frequency center station N, the Beidou comparison reference receiver A2 and the GNSS satellite common-view comparison device B2 are respectively connected to the 10MHz frequency signal and 1PPS signal output by the time and frequency output reference point 2 of station N, and the line delay between receiver A2 and B2 connected to the time and frequency output reference point 2 is accurately measured and calibrated.

[0030] Step 4: The time comparison link consisting of the B1 and B2 common-view time comparison equipment of the measured GNSS satellites on stations M and N performs time comparison, and the time comparison link consisting of the Beidou comparison reference receivers A1 and A2 performs time comparison synchronously.

[0031] Step 5: Conduct continuous testing for 7 days and record the clock difference measurement results of the common-view time comparison equipment B1 and B2 for the tested GNSS satellites and the Beidou comparison reference receivers A1 and A2.

[0032] Step 6: Calculate the time comparison accuracy d (ns) between the time comparison equipment B1 and B2 using equation (1):

[0033] In the formula: x T,i —The measured time is compared with the i-th clock difference measurement result of equipment B1 and B2;

[0034] x B,i —The i-th clock difference measurement result of Beidou comparison reference receivers A1 and A2;

[0035] n—Number of valid measurement results; a total of 623 were collected within 7 days.

[0036] Based on the above formula (1), the test results are statistically calculated to obtain d = 4.7 (ns);

[0037] Step 7: Compare the measured time of equipment B1 and B2 at a baseline length of less than 3000km. 指标 =5ns, the index accuracy is three times that of 1.7ns, the time comparison accuracy d of Beidou comparison reference receivers A1 and A2 基准 = 2.3ns, because If the accuracy of the time comparison benchmark cannot reach three times that of the target, the error of the time comparison benchmark must be taken into account during the evaluation. Then it is determined that the time comparison accuracy of the time comparison equipment B1 and B2 meets the index requirements.

[0038] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A test evaluation method for time comparison equipment based on BeiDou comparison reference error, characterized in that, Includes the following steps: Step 1: Calibrate the BeiDou comparison reference receivers A1 and A2 at a qualified calibration center. The time comparison accuracy of A1 and A2 at a specific length baseline is d. 基准 ; Step 2: Using the 10MHz frequency signal and 1PPS signal output by the time comparison station E as time-frequency reference 1, the Beidou comparison reference receiver A1 and the B1 station in the time comparison equipment under test are both connected to time-frequency reference 1 to calibrate the time delay of each line. Step 3: Using the 10MHz frequency signal and 1PPS signal output by the clock of time comparison station F as time and frequency reference 2, the Beidou comparison reference receiver A2 and station B2 in the time comparison equipment under test are connected to time and frequency reference 2 to calibrate the delay of each link. Step 4: The time comparison link consisting of the time comparison equipment B1 and B2 performs time comparison, and the time comparison link consisting of the Beidou comparison reference receivers A1 and A2 performs time comparison synchronously. Step 5: Conduct continuous testing for no less than 7 days and record the clock difference measurement results of the time comparison equipment B1 and B2 and the Beidou comparison reference receivers A1 and A2. Step 6: Calculate the time comparison accuracy between the measured time comparison equipment B1 and B2 using the following formula 1). ns: 1） In the formula: —The measured time is compared with the i-th clock difference measurement result of equipment B1 and B2; —The i-th clock difference measurement result of Beidou comparison reference receivers A1 and A2; —Number of valid measurement results; Step 7: Determine if it is qualified.

2. The time comparison equipment test evaluation method based on BeiDou comparison reference error as described in claim 1, characterized in that: The judgment in step seven is that if the time comparison accuracy of BeiDou comparison reference receivers A1 and A2 is... The test time should be no less than the comparison between equipment B1 and B2 indicators. 3 times, that is Then when ≤ If the time comparison accuracy of the tested time comparison equipment B1 and B2 meets the index requirements, it is deemed qualified; otherwise, it is deemed unqualified. If the time comparison accuracy of the Beidou comparison reference receiver A1 and A2 is... Compare equipment B1 and B2 indicators below the test time. 3 times, that is Then when ≤ If the time comparison accuracy of the time comparison equipment B1 and B2 meets the index requirements, it is considered qualified; otherwise, it is considered unqualified.

Images