Verification Regulation of Test Equipment for Vehicle Speed Radar Measurement Meters
Some standard content:
National Metrology Verification Regulation of the People's Republic of China JJG771—2010
Test Equipment for Vehicle Speed Radar Measurement Meters2010-01-05Promulgated
Implementation on 2010-07-05
Promulgated by the General Administration of Quality Supervision, Inspection and QuarantineJJG771—2010
Verification Regulation of Test Equipment for Vehicle Speed Radar Measurement MetersJJG771—2010
Replaces JJG771-1992
This regulation was approved by the General Administration of Quality Supervision, Inspection and Quarantine on January 5, 2010, and came into effect on July 5, 2010.
Responsible unit: National Technical Committee on Vibration, Shock and Rotational Speed Metrology Main drafting unit: Beijing Institute of Metrology and Testing Science Participating drafting unit: China Testing Technology Research Institute Shanghai Institute of Metrology and Testing Technology
Jiangsu Institute of Metrology Science
Anhui Landun Optoelectronics Co., Ltd.
206th Institute of China North Industries Group Corporation
This regulation is entrusted to the National Technical Committee on Vibration, Shock and Rotational Speed Metrology to be responsible for the interpretation of this regulation Main drafter:
JJG771—2010
Zhu Junjie (Beijing Institute of Metrology and Testing Science) Gao Yang (Beijing Institute of Metrology and Testing Science) Participating drafters:
Yang Chunsheng (China Testing Technology Research Institute) Huang Yuhui (Shanghai Institute of Metrology and Testing Technology) Lin Zhongyang (Jiangsu Institute of Metrology) Qian Jiang (Anhui Landun Optoelectronics Co., Ltd.) Wang Qimin (No. 206 Institute of China North Industries Group Corporation) 1
References
4 Metrological performance requirements
4.1 Microwave frequency counter
4.2 Target speed simulation device
5 General technical requirements Request
5.1 Appearance
5.2 Others
6 Control of measuring instruments
6.1 Verification conditions
6.2 Verification items
6.3 Verification methods
6.4 Processing of verification results
6.5 Verification cycle
JJG771—2010
Appendix A Target speed simulation device verification record (recommended) format Appendix B
Verification certificate inner page format
Appendix C Verification result notification inner page format Appendix D Doppler Frequency theory value/speed value comparison table (1)
(1)
(1)
(2)
(3)
(3)
(6)
(10)
(11)
(12)
1 Scope
JJG771—2010
Verification procedures for verification devices of motor vehicle radar speed guns This procedure applies to the initial verification, subsequent verification and in-use inspection of verification devices of motor vehicle radar speed guns (hereinafter referred to as verification devices).
Referencesbzxz.net
JJG841-1993 Verification procedures for microwave frequency counters When using this procedure, attention should be paid to the use of the current valid versions of the above-mentioned references. 3 Overview
The verification device consists of two parts: a microwave frequency counter and a target speed simulation device. The microwave frequency counter is used to calibrate the microwave emission frequency error of the motor vehicle radar speedometer; the Japanese standard speed simulation device generates a simulated speed Doppler frequency signal, and uses its test channel (equipped with three modulators of X, K and Ka bands) to calibrate the speed measurement error of the motor vehicle radar speedometer.
4 Metrological performance requirements
4.1 Microwave frequency counter
4.1.1 Frequency measurement range: (8~40) GHz4.1.2 Frequency accuracy: 1×10-6
4.1.31s Frequency stability: 1×10-9
4.2 Target speed simulation device
4.2.1 Speed range: at least 20~200km/h According to the speed range requirements, the corresponding Doppler frequency range is shown in Table 1. Table 1 Doppler frequency range
Radar speed meter microwave transmission frequency nominal value fo/MHz
X band:
K band:
Ka band:
4.2.2 Maximum allowable speed error: ±0.30km/h Doppler frequency range
3903901
895~8951
1301~13009
Root According to the requirements of the maximum allowable speed error index, the frequency parameter index of the target speed simulation device is required to be: 4.2.2.1 Frequency error: ±1Hz
JJG771-2010
4.2.2.2 Frequency stability: α(t)≤3×10-410525MHz103ms;
24150MHzt~45ms;
35100MHz~31ms.
4.2.2.31h Frequency fluctuation: S≤1X103
5 General technical requirements
5.1 Appearance
The motor vehicle radar speed meter calibration device should have a nameplate indicating the product name, specification model and number, and the name of the manufacturer.
5.2 Others
5.2.1 The verification device of the motor vehicle radar speed meter should have no obvious mechanical damage, and each functional switch, knob, and button should be flexible and reliable, and each output interface should be firmly connected. 5.2.2 The target speed simulation device should be able to output two analog speed Doppler frequency signals, the signal amplitude of which is adjustable, and the output display can be the analog speed Doppler frequency value (Hz) or the speed value (km/h). 6 Measuring instrument control
6.1 Verification conditions
6.1.1 Environmental conditions
6.1.1.1 Temperature: (20±5)℃;
Humidity: <85%RH;
Power supply: AC (220±22)V:
There should be no mechanical vibration and electromagnetic field interference around the verification device of the motor vehicle radar speed meter that may affect normal operation. Verification equipment (see Table 2)
Table 2 Verification equipment
Verification items
Frequency measurement range
Frequency accuracy
1s frequency stability
Speed range
1. Frequency synthesis signal generator;
2. Power meter;
3. Frequency standard source for crystal oscillator verification;
4. Measuring device for crystal oscillator verification
General counter
Verification equipment
Technical characteristics||tt| |According to JJG841-1993 "Verification Regulations for Microwave Frequency Counters"
Frequency range: 1Hz~10MHz
Period measurement: 0.4us~10s
Sampling (gate) time: 1ms~1000sSensitivity: better than 30mV
Rated rate accuracy: 1X10-6
1sFrequency stability: 1×10-8
Verification items
Speed error
6.2 Verification items
See Table 3.
Verification items
General technical requirements inspection
JJG771-2010
Table 2 (Continued)
Calibration equipment
General counter
Divider
Table 3 Calibration items
First calibration
Frequency measurement range
Microwave frequency counter
Target speed simulation device
6.3 Calibration method
Frequency accuracy
1s frequency stability
Speed range
Speed error
6.3.1 Inspection of general technical requirements
Technical characteristics
Technical characteristics of general counters are the same as above
Frequency range: (0.1～20)kHz
Frequency division multiple: 1～16
Sensitivity: better than 30mV
Subsequent verification
In-use inspection
Inspect the general technical requirements of the motor vehicle radar speed meter verification device in accordance with Articles 5.1 and 5.2 of this Regulation, and the results should meet the requirements.
6.3.2 Verification of frequency measurement range, frequency accuracy and 1s frequency stability According to the method specified in JJG841-1993 "Verification Procedure for Microwave Frequency Counters", the frequency measurement range, frequency accuracy and 1s frequency stability shall be verified, and the verification results shall meet the requirements of Articles 4.1.1, 4.1.2 and 4.1.3 of this regulation.
6.3.3 Speed range
Verification of the frequency range of the target speed simulation device: 1) Connect according to Figure 1. Before verification, the target speed simulation device and the general counter shall be preheated for the specified time before the following verifications can be carried out. Target speed simulation device
General counter
Figure 1 Frequency range verification block diagram
2) The target speed simulation device outputs a frequency signal, and the speed verification points shall be selected at 3 points evenly distributed within the specified range (such as 20km/h, 100km/h and 200km/h, etc.). 3
JJG771—2010
3) Doppler frequency fa and speed setting value v shall satisfy the following formula: kifou
Wherein: fa—Doppler frequency, Hz;
Electromagnetic wave propagation speed, 0.299792458Gm/s; Unit conversion factor, ki=10-3/3.6;
fo—nominal value of microwave emission frequency of radar speed meter, MHz—speed setting value, km/h.
4) Use a general counter to measure the output frequency of the target speed simulation device, and set the gate time to 10s; its frequency range shall meet the requirements of Article 4.2.1 of this Regulation. 6.3.4 Speed error
6.3.4.1 Verification of frequency error of Japanese standard speed simulation device 1) See Figure 1 for the frequency error verification block diagram. The target speed simulation device outputs a frequency signal. The speed verification points should be selected at 3 points evenly distributed within the specified range (such as 20km/h, 100km/h and 200km/h, etc.). The corresponding frequency value of each speed point is measured 3 times using a universal counter, and the average value of the 3 measurements is taken as the actual frequency value of the speed point. The gate time is set to 10s. 2) Calculate the frequency error according to formula (2):
Afa=fa-fao
Where: Afa-frequency error, Hz, retain one significant digit, fa actual frequency value, Hz;
fao-Doppler frequency theoretical value, Hz, calculated according to formula (1) and rounded to 0.1Hz. Its frequency error should meet the requirements of Article 4.2.2.1 of this Regulation. 6.3.4.2 Verification of frequency stability of target speed simulation device (2)
1) See Figure 1 or Figure 2 for the frequency stability verification block diagram. The target speed simulation device outputs a frequency signal, and the speed verification points should be evenly distributed within the specified range and selected at 3 points (such as 20km/h, 100km/h and .200km/h, etc.). Target speed simulation device
Divider
Figure 2 Frequency stability verification block diagram
Universal counter
Method 1: See Figure 2. Use a universal counter to measure the output period of the target speed simulation device, adjust the frequency division multiple of the divider according to the requirements of Article 4.2.2.2 of this regulation, and select the specified sampling time. Continuously sample the frequency signal, and the number of sampling groups m is 100.
Method 2: See Figure 1. Use a universal counter (whose gate time can be adjusted arbitrarily) to measure the output frequency of the target speed simulation device, and select the specified sampling time. Continuously sample the frequency signal, and the number of sampling groups m is 100. 2) Calculate the frequency stability of method 1 according to formula (3). ：p
?k2Mfao
(t+1 - t;)2
where: t, ti, T+1
JJG771—2010
are the average sampling time after frequency division, the sampling time value of the ith and ith tenth measurement, ms;
the number of measurement groups;
k2——unit conversion factor, kz=10-3:M——frequency division multiple of the frequency divider;
cycle multiplication (expansion) multiple.
3) Calculate the frequency stability of method 2 according to formula (4). ：g
（ff)2
faoN台
where: f, ft1——are the ith and ith tenth frequency measurement values, Hz. Its frequency stability shall meet the requirements of Article 4.2.2.2 of this Regulation. 6.3.4.3 Verification of 1h frequency fluctuation of target speed simulation device (4)
1) The frequency fluctuation verification block diagram is shown in Figure 1. The target speed simulation device outputs a frequency signal, and the speed verification points shall be selected at 3 points evenly distributed within the specified range (such as 20km/h, 100km/h and 200km/h, etc.).
2) The universal counter gate time is set to 10s, and the output frequency of the target speed simulation device is measured once every 5 minutes with the universal counter, for a total of 1h.
3) Calculate the frequency fluctuation S according to formula (5):
S=fa mx -fa min
Where: famax—--the maximum value of the frequency measured within 1h, Hz; famin—the minimum value of the frequency measured within 1h, Hz. Its frequency fluctuation shall meet the requirements of Article 4.2.2.3 of this Regulation. 6.3.4.4 Calculation of speed error
Calculate the speed error A according to formula (6):
A=2V++
Wherein: A
-speed error, km/h
speed error caused by frequency error, km/h, Ai=-2fao
speed error caused by frequency stability, km/h; △2=ou, where is the conversion factor between the square root of the Allan variance and the standard deviation; for the target speed simulation device using a crystal oscillator, take 2/3; for the target speed simulation device using an RC oscillator, take 1; α is determined by formula (3) or (4);
—-speed error caused by frequency fluctuation, km/h, A-speed value, km/h
The speed error shall comply with the requirements of Article 4.2.2 of this Regulation. S
6.3.5 According to the requirements of Article 6.3.3 and Article 6.3.4 of this Regulation, the frequencies corresponding to the X, K and Ka band speed calibration points of each of the two outputs of the target speed simulation device shall be calibrated, and the calibration results shall comply with the requirements of Article 4.2 of this Regulation.
6.4 Handling of calibration results
A calibration certificate shall be issued to the calibration device that has passed the calibration; a calibration result notice shall be issued to the calibration device that has failed the calibration, and the unqualified items shall be indicated.
Note: Reports can be issued separately for the microwave frequency counter and the target speed simulator. 6.5 Calibration cycle
The calibration cycle of the calibration device is 1 year. The calibration device must be recalibrated after maintenance. Appendix A
Inspection unit
Manufacturer
Ambient temperature
Calibration date
JJG771—2010
Target speed simulation device calibration record (recommended) format Model Specification
℃Relative humidity
Year Month Day
Calibrator
Factory number
Calibration location
Verifier
Nature of calibration: Initial calibration Port Subsequent calibration Port 1 In-use inspection
Port I port
Port II port
1 General technical requirements
Qualified port
Calibration of speed range
Speed value/(km/h)
Corresponding simulated speed Doppler
Frequency measurement value/Hz
Verification of speed error
Speed value/(km/h)
Corresponding simulated speed Doppler
Frequency theoretical value/Hz
Frequency measurement value/Hz
Actual frequency value/Hz
Frequency error/Hz
Speed error caused by frequency error
/(km/h）
Unqualified port
Verification of speed range and speed error
X-band
K-band port
Ka-band
Verification of frequency range
Verification of frequency error3 Speed range
Testing of the frequency range of the target speed simulation device: 1) Connect as shown in Figure 1. Before the test, the target speed simulation device and the universal counter should be preheated for the specified time before the following tests can be carried out. Target speed simulation device
Universal counter
Figure 1 Frequency range test block diagram
2) The target speed simulation device outputs a frequency signal, and the speed test points should be evenly distributed within the specified range and selected at 3 points (such as 20km/h, 100km/h and 200km/h, etc.). 3
JJG771—2010
3) Doppler frequency fa and speed setting value v shall satisfy the following formula: kifou
Wherein: fa—Doppler frequency, Hz;
Electromagnetic wave propagation speed, 0.299792458Gm/s; Unit conversion factor, ki=10-3/3.6;
fo—nominal value of microwave emission frequency of radar speed meter, MHz—speed setting value, km/h.
4) Use a general counter to measure the output frequency of the target speed simulation device, and set the gate time to 10s; its frequency range shall meet the requirements of Article 4.2.1 of this Regulation. 6.3.4 Speed error
6.3.4.1 Verification of frequency error of Japanese standard speed simulation device 1) See Figure 1 for the frequency error verification block diagram. The target speed simulation device outputs a frequency signal. The speed verification points should be selected at 3 points evenly distributed within the specified range (such as 20km/h, 100km/h and 200km/h, etc.). The corresponding frequency value of each speed point is measured 3 times using a universal counter, and the average value of the 3 measurements is taken as the actual frequency value of the speed point. The gate time is set to 10s. 2) Calculate the frequency error according to formula (2):
Afa=fa-fao
Where: Afa-frequency error, Hz, retain one significant digit, fa actual frequency value, Hz;
fao-Doppler frequency theoretical value, Hz, calculated according to formula (1) and rounded to 0.1Hz. Its frequency error should meet the requirements of Article 4.2.2.1 of this Regulation. 6.3.4.2 Verification of frequency stability of target speed simulation device (2)
1) See Figure 1 or Figure 2 for the frequency stability verification block diagram. The target speed simulation device outputs a frequency signal, and the speed verification points should be evenly distributed within the specified range and selected at 3 points (such as 20km/h, 100km/h and .200km/h, etc.). Target speed simulation device
Divider
Figure 2 Frequency stability verification block diagram
Universal counter
Method 1: See Figure 2. Use a universal counter to measure the output period of the target speed simulation device, adjust the frequency division multiple of the divider according to the requirements of Article 4.2.2.2 of this regulation, and select the specified sampling time. Continuously sample the frequency signal, and the number of sampling groups m is 100.
Method 2: See Figure 1. Use a universal counter (whose gate time can be adjusted arbitrarily) to measure the output frequency of the target speed simulation device, and select the specified sampling time. Continuously sample the frequency signal, and the number of sampling groups m is 100. 2) Calculate the frequency stability of method 1 according to formula (3). ：p
?k2Mfao
(t+1 - t;)2
where: t, ti, T+1
JJG771—2010
are the average sampling time after frequency division, the sampling time value of the ith and ith tenth measurement, ms;
the number of measurement groups;
k2——unit conversion factor, kz=10-3:M——frequency division multiple of the frequency divider;
cycle multiplication (expansion) multiple.
3) Calculate the frequency stability of method 2 according to formula (4). ：g
（ff)2
faoN台
where: f, ft1——are the ith and ith tenth frequency measurement values, Hz. Its frequency stability shall meet the requirements of Article 4.2.2.2 of this Regulation. 6.3.4.3 Verification of 1h frequency fluctuation of target speed simulation device (4)
1) The frequency fluctuation verification block diagram is shown in Figure 1. The target speed simulation device outputs a frequency signal, and the speed verification points shall be selected at 3 points evenly distributed within the specified range (such as 20km/h, 100km/h and 200km/h, etc.).
2) The universal counter gate time is set to 10s, and the output frequency of the target speed simulation device is measured once every 5 minutes with the universal counter, for a total of 1h.
3) Calculate the frequency fluctuation S according to formula (5):
S=fa mx -fa min
Where: famax—--the maximum value of the frequency measured within 1h, Hz; famin—the minimum value of the frequency measured within 1h, Hz. Its frequency fluctuation shall meet the requirements of Article 4.2.2.3 of this Regulation. 6.3.4.4 Calculation of speed error
Calculate the speed error A according to formula (6):
A=2V++
Wherein: A
-speed error, km/h
speed error caused by frequency error, km/h, Ai=-2fao
speed error caused by frequency stability, km/h; △2=ou, where is the conversion factor between the square root of the Allan variance and the standard deviation; for the target speed simulation device using a crystal oscillator, take 2/3; for the target speed simulation device using an RC oscillator, take 1; α is determined by formula (3) or (4);
—-speed error caused by frequency fluctuation, km/h, A-speed value, km/h
The speed error shall comply with the requirements of Article 4.2.2 of this Regulation. S
6.3.5 According to the requirements of Article 6.3.3 and Article 6.3.4 of this Regulation, the frequencies corresponding to the X, K and Ka band speed calibration points of each of the two outputs of the target speed simulation device shall be calibrated, and the calibration results shall comply with the requirements of Article 4.2 of this Regulation.
6.4 Handling of calibration results
A calibration certificate shall be issued to the calibration device that has passed the calibration; a calibration result notice shall be issued to the calibration device that has failed the calibration, and the unqualified items shall be indicated.
Note: Reports can be issued separately for the microwave frequency counter and the target speed simulator. 6.5 Calibration cycle
The calibration cycle of the calibration device is 1 year. The calibration device must be recalibrated after maintenance. Appendix A
Inspection unit
Manufacturer
Ambient temperature
Calibration date
JJG771—2010
Target speed simulation device calibration record (recommended) format Model Specification
℃Relative humidity
Year Month Day
Calibrator
Factory number
Calibration location
Verifier
Nature of calibration: Initial calibration Port Subsequent calibration Port 1 In-use inspection
Port I port
Port II port
1 General technical requirements
Qualified port
Calibration of speed range
Speed value/(km/h)
Corresponding simulated speed Doppler
Frequency measurement value/Hz
Verification of speed error
Speed value/(km/h)
Corresponding simulated speed Doppler
Frequency theoretical value/Hz
Frequency measurement value/Hz
Actual frequency value/Hz
Frequency error/Hz
Speed error caused by frequency error
/(km/h）
Unqualified port
Verification of speed range and speed error
X-band
K-band port
Ka-band
Verification of frequency range
Verification of frequency error3 Speed range
Testing of the frequency range of the target speed simulation device: 1) Connect as shown in Figure 1. Before the test, the target speed simulation device and the universal counter should be preheated for the specified time before the following tests can be carried out. Target speed simulation device
Universal counter
Figure 1 Frequency range test block diagram
2) The target speed simulation device outputs a frequency signal, and the speed test points should be evenly distributed within the specified range and selected at 3 points (such as 20km/h, 100km/h and 200km/h, etc.). 3
JJG771—2010
3) Doppler frequency fa and speed setting value v shall satisfy the following formula: kifou
Wherein: fa—Doppler frequency, Hz;
Electromagnetic wave propagation speed, 0.299792458Gm/s; Unit conversion factor, ki=10-3/3.6;
fo—nominal value of microwave emission frequency of radar speed meter, MHz—speed setting value, km/h.
4) Use a general counter to measure the output frequency of the target speed simulation device, and set the gate time to 10s; its frequency range shall meet the requirements of Article 4.2.1 of this Regulation. 6.3.4 Speed error
6.3.4.1 Verification of frequency error of Japanese standard speed simulation device 1) See Figure 1 for the frequency error verification block diagram. The target speed simulation device outputs a frequency signal. The speed verification points should be selected at 3 points evenly distributed within the specified range (such as 20km/h, 100km/h and 200km/h, etc.). The corresponding frequency value of each speed point is measured 3 times using a universal counter, and the average value of the 3 measurements is taken as the actual frequency value of the speed point. The gate time is set to 10s. 2) Calculate the frequency error according to formula (2):
Afa=fa-fao
Where: Afa-frequency error, Hz, retain one significant digit, fa actual frequency value, Hz;
fao-Doppler frequency theoretical value, Hz, calculated according to formula (1) and rounded to 0.1Hz. Its frequency error should meet the requirements of Article 4.2.2.1 of this Regulation. 6.3.4.2 Verification of frequency stability of target speed simulation device (2)
1) See Figure 1 or Figure 2 for the frequency stability verification block diagram. The target speed simulation device outputs a frequency signal, and the speed verification points should be evenly distributed within the specified range and selected at 3 points (such as 20km/h, 100km/h and .200km/h, etc.). Target speed simulation device
Divider
Figure 2 Frequency stability verification block diagram
Universal counter
Method 1: See Figure 2. Use a universal counter to measure the output period of the target speed simulation device, adjust the frequency division multiple of the divider according to the requirements of Article 4.2.2.2 of this regulation, and select the specified sampling time. Continuously sample the frequency signal, and the number of sampling groups m is 100.
Method 2: See Figure 1. Use a universal counter (whose gate time can be adjusted arbitrarily) to measure the output frequency of the target speed simulation device, and select the specified sampling time. Continuously sample the frequency signal, and the number of sampling groups m is 100. 2) Calculate the frequency stability of method 1 according to formula (3). ：p
?k2Mfao
(t+1 - t;)2
where: t, ti, T+1
JJG771—2010
are the average sampling time after frequency division, the sampling time value of the ith and ith tenth measurement, ms;
the number of measurement groups;
k2——unit conversion factor, kz=10-3:M——frequency division multiple of the frequency divider;
cycle multiplication (expansion) multiple.
3) Calculate the frequency stability of method 2 according to formula (4). ：g
（ff)2
faoN台
where: f, ft1——are the ith and ith tenth frequency measurement values, Hz. Its frequency stability shall meet the requirements of Article 4.2.2.2 of this Regulation. 6.3.4.3 Verification of 1h frequency fluctuation of target speed simulation device (4)
1) The frequency fluctuation verification block diagram is shown in Figure 1. The target speed simulation device outputs a frequency signal, and the speed verification points shall be selected at 3 points evenly distributed within the specified range (such as 20km/h, 100km/h and 200km/h, etc.).
2) The universal counter gate time is set to 10s, and the output frequency of the target speed simulation device is measured once every 5 minutes with the universal counter, for a total of 1h.
3) Calculate the frequency fluctuation S according to formula (5):
S=fa mx -fa min
Where: famax—--the maximum value of the frequency measured within 1h, Hz; famin—the minimum value of the frequency measured within 1h, Hz. Its frequency fluctuation shall meet the requirements of Article 4.2.2.3 of this Regulation. 6.3.4.4 Calculation of speed error
Calculate the speed error A according to formula (6):
A=2V++
Wherein: A
-speed error, km/h
speed error caused by frequency error, km/h, Ai=-2fao
speed error caused by frequency stability, km/h; △2=ou, where is the conversion factor between the square root of the Allan variance and the standard deviation; for the target speed simulation device using a crystal oscillator, take 2/3; for the target speed simulation device using an RC oscillator, take 1; α is determined by formula (3) or (4);
—-speed error caused by frequency fluctuation, km/h, A-speed value, km/h
The speed error shall comply with the requirements of Article 4.2.2 of this Regulation. S
6.3.5 According to the requirements of Article 6.3.3 and Article 6.3.4 of this Regulation, the frequencies corresponding to the X, K and Ka band speed calibration points of each of the two outputs of the target speed simulation device shall be calibrated, and the calibration results shall comply with the requirements of Article 4.2 of this Regulation.
6.4 Handling of calibration results
A calibration certificate shall be issued to the calibration device that has passed the calibration; a calibration result notice shall be issued to the calibration device that has failed the calibration, and the unqualified items shall be indicated.
Note: Reports can be issued separately for the microwave frequency counter and the target speed simulator. 6.5 Calibration cycle
The calibration cycle of the calibration device is 1 year. The calibration device must be recalibrated after maintenance. Appendix A
Inspection unit
Manufacturer
Ambient temperature
Calibration date
JJG771—2010
Target speed simulation device calibration record (recommended) format Model Specification
℃Relative humidity
Year Month Day
Calibrator
Factory number
Calibration location
Verifier
Nature of calibration: Initial calibration Port Subsequent calibration Port 1 In-use inspection
Port I port
Port II port
1 General technical requirements
Qualified port
Calibration of speed range
Speed value/(km/h)
Corresponding simulated speed Doppler
Frequency measurement value/Hz
Verification of speed error
Speed value/(km/h)
Corresponding simulated speed Doppler
Frequency theoretical value/Hz
Frequency measurement value/Hz
Actual frequency value/Hz
Frequency error/Hz
Speed error caused by frequency error
/(km/h）
Unqualified port
Verification of speed range and speed error
X-band
K-band port
Ka-band
Verification of frequency range
Verification of frequency error1. Verification of frequency error of standard speed simulation device 1) The frequency error verification block diagram is shown in Figure 1. The target speed simulation device outputs the frequency signal. The speed verification points should be selected at 3 points evenly distributed within the specified range (such as 20km/h, 100km/h and 200km/h, etc.). The corresponding frequency value of each speed point is measured 3 times using a universal counter, and the average value of the 3 measurements is taken as the actual frequency value of the speed point. The gate time is set to 10s. 2) Calculate the frequency error according to formula (2):
Afa=fa—fao
Where: Afa—frequency error, Hz, retain one significant digit, fa actual frequency value, Hz;
fao—Doppler frequency theoretical value, Hz, calculated according to formula (1) and rounded to 0.1Hz. Its frequency error should meet the requirements of Article 4.2.2.1 of this regulation. 6.3.4.2 Verification of frequency stability of target speed simulation device (2)
1) See Figure 1 or Figure 2 for the frequency stability verification block diagram. The target speed simulation device outputs a frequency signal. The speed verification points should be selected at 3 points evenly distributed within the specified range (such as 20km/h, 100km/h and .200km/h, etc.). Target speed simulation device
Divider
Figure 2 Frequency stability verification block diagram
Universal counter
Method 1: See Figure 2. Use a universal counter to measure the output period of the target speed simulation device, adjust the frequency division multiple of the divider according to the requirements of Article 4.2.2.2 of this Regulation, and select the specified sampling time. Continuously sample the frequency signal, and the number of sampling groups m is 100.
Method 2: See Figure 1. Use a universal counter (whose gate time can be adjusted arbitrarily) to measure the output frequency of the target speed simulation device and select the specified sampling time. The frequency signal is sampled continuously, and the number of sampling groups m is 100. 2) The frequency stability of method 1 is calculated according to formula (3). : p
?k2Mfao
(t+1 - t;)2
Where: t, ti, T+1
JJG771—2010
are the average value of the sampling time after frequency division, the sampling time value of the ith and ith 11th measurement, ms respectively;
the number of measurement groups;
k2——unit conversion factor, kz=10-3: M——the frequency division multiple of the divider;
the period multiplication (expansion) multiple.
3) The frequency stability of method 2 is calculated according to formula (4). ：g
（ff)2
faoN台
Where: f, ft1—represent the i-th and i+1st frequency measurement values, Hz. Its frequency stability shall comply with the requirements of Article 4.2.2.2 of this Regulation. 6.3.4.3 Verification of 1h frequency fluctuation of target speed simulation device (4)
1) The frequency fluctuation verification block diagram is shown in Figure 1. The target speed simulation device outputs a frequency signal, and the speed verification points shall be selected at 3 points evenly distributed within the specified range (such as 20km/h, 100km/h and 200km/h, etc.).
2) The universal counter gate time is set to 10s, and the output frequency of the target speed simulation device is measured once every 5 minutes with the universal counter, for a total of 1h.
3) Calculate the frequency fluctuation S according to formula (5):
S=fa mx -fa min
Wherein: famax—--the maximum value of the frequency measured within 1 hour, Hz; famin—the minimum value of the frequency measured within 1 hour, Hz. The frequency fluctuation shall comply with the requirements of Article 4.2.2.3 of this Regulation. 6.3.4.4 Calculation of speed error
Calculate the speed error A according to formula (6):
A=2V++
Wherein: A
-speed error, km/h
speed error caused by frequency error, km/h, Ai=-2fao
speed error caused by frequency stability, km/h; △2=ou, where is the conversion factor between the square root of the Allan variance and the standard deviation; for the target speed simulation device using a crystal oscillator, take 2/3; for the target speed simulation device using an RC oscillator, take 1; α is determined by formula (3) or (4);
—-speed error caused by frequency fluctuation, km/h, A-speed value, km/h
The speed error shall comply with the requirements of Article 4.2.2 of this Regulation. S
6.3.5 According to the requirements of Article 6.3.3 and Article 6.3.4 of this Regulation, the frequencies corresponding to the X, K and Ka band speed calibration points of each of the two outputs of the target speed simulation device shall be calibrated, and the calibration results shall comply with the requirements of Article 4.2 of this Regulation.
6.4 Handling of calibration results
A calibration certificate shall be issued to the calibration device that has passed the calibration; a calibration result notice shall be issued to the calibration device that has failed the calibration, and the unqualified items shall be indicated.
Note: Reports can be issued separately for the microwave frequency counter and the target speed simulator. 6.5 Calibration cycle
The calibration cycle of the calibration device is 1 year. The calibration device must be recalibrated after maintenance. Appendix A
Inspection unit
Manufacturer
Ambient temperature
Calibration date
JJG771—2010
Target speed simulation device calibration record (recommended) format Model Specification
℃Relative humidity
Year Month Day
Calibrator
Factory number
Calibration location
Verifier
Nature of calibration: Initial calibration Port Subsequent calibration Port 1 In-use inspection
Port I port
Port II port
1 General technical requirements
Qualified port
Calibration of speed range
Speed value/(km/h)
Corresponding simulated speed Doppler
Frequency measurement value/Hz
Verification of speed error
Speed value/(km/h)
Corresponding simulated speed Doppler
Frequency theoretical value/Hz
Frequency measurement value/Hz
Actual frequency value/Hz
Frequency error/Hz
Speed error caused by frequency error
/(km/h）
Unqualified port
Verification of speed range and speed error
X-band
K-band port
Ka-band
Verification of frequency range
Verification of frequency error1. Verification of frequency error of standard speed simulation device 1) The frequency error verification block diagram is shown in Figure 1. The target speed simulation device outputs the frequency signal. The speed verification points should be selected at 3 points evenly distributed within the specified range (such as 20km/h, 100km/h and 200km/h, etc.). The corresponding frequency value of each speed point is measured 3 times using a universal counter, and the average value of the 3 measurements is taken as the actual frequency value of the speed point. The gate time is set to 10s. 2) Calculate the frequency error according to formula (2):
Afa=fa—fao
Where: Afa—frequency error, Hz, retain one significant digit, fa actual frequency value, Hz;
fao—Doppler frequency theoretical value, Hz, calculated according to formula (1) and rounded to 0.1Hz. Its frequency error should meet the requirements of Article 4.2.2.1 of this regulation. 6.3.4.2 Verification of frequency stability of target speed simulation device (2)
1) See Figure 1 or Figure 2 for the frequency stability verification block diagram. The target speed simulation device outputs a frequency signal. The speed verification points should be selected at 3 points evenly distributed within the specified range (such as 20km/h, 100km/h and .200km/h, etc.). Target speed simulation device
Divider
Figure 2 Frequency stability verification block diagram
Universal counter
Method 1: See Figure 2. Use a universal counter to measure the output period of the target speed simulation device, adjust the frequency division multiple of the divider according to the requirements of Article 4.2.2.2 of this Regulation, and select the specified sampling time. Continuously sample the frequency signal, and the number of sampling groups m is 100.
Method 2: See Figure 1. Use a universal counter (whose gate time can be adjusted arbitrarily) to measure the output frequency of the target speed simulation device and select the specified sampling time. The frequency signal is sampled continuously, and the number of sampling groups m is 100. 2) The frequency stability of method 1 is calculated according to formula (3). : p
?k2Mfao
(t+1 - t;)2
Where: t, ti, T+1
JJG771—2010
are the average value of the sampling time after frequency division, the sampling time value of the ith and ith 11th measurement, ms respectively;
the number of measurement groups;
k2——unit conversion factor, kz=10-3: M——the frequency division multiple of the divider;
the period multiplication (expansion) multiple.
3) The frequency stability of method 2 is calculated according to formula (4). ：g
（ff)2
faoN台
Where: f, ft1—represent the i-th and i+1st frequency measurement values, Hz. Its frequency stability shall comply with the requirements of Article 4.2.2.2 of this Regulation. 6.3.4.3 Verification of 1h frequency fluctuation of target speed simulation device (4)
1) The frequency fluctuation verification block diagram is shown in Figure 1. The target speed simulation device outputs a frequency signal, and the speed verification points shall be selected at 3 points evenly distributed within the specified range (such as 20km/h, 100km/h and 200km/h, etc.).
2) The universal counter gate time is set to 10s, and the output frequency of the target speed simulation device is measured once every 5 minutes with the universal counter, for a total of 1h.
3) Calculate the frequency fluctuation S according to formula (5):
S=fa mx -fa min
Wherein: famax—--the maximum value of the frequency measured within 1 hour, Hz; famin—the minimum value of the frequency measured within 1 hour, Hz. The frequency fluctuation shall comply with the requirements of Article 4.2.2.3 of this Regulation. 6.3.4.4 Calculation of speed error
Calculate the speed error A according to formula (6):
A=2V++
Wherein: A
-speed error, km/h
speed error caused by frequency error, km/h, Ai=-2fao
speed error caused by frequency stability, km/h; △2=ou, where is the conversion factor between the square root of the Allan variance and the standard deviation; for the target speed simulation device using a crystal oscillator, take 2/3; for the target speed simulation device using an RC oscillator, take 1; α is determined by formula (3) or (4);
—-speed error caused by frequency fluctuation, km/h, A-speed value, km/h
The speed error shall comply with the requirements of Article 4.2.2 of this Regulation. S
6.3.5 According to the requirements of Article 6.3.3 and Article 6.3.4 of this Regulation, the frequencies corresponding to the X, K and Ka band speed calibration points of each of the two outputs of the target speed simulation device shall be calibrated, and the calibration results shall comply with the requirements of Article 4.2 of this Regulation.
6.4 Handling of calibration results
A calibration certificate shall be issued to the calibration device that has passed the calibration; a calibration result notice shall be issued to the calibration device that has failed the calibration, and the unqualified items shall be indicated.
Note: Reports can be issued separately for the microwave frequency counter and the target speed simulator. 6.5 Calibration cycle
The calibration cycle of the calibration device is 1 year. The calibration device must be recalibrated after maintenance. Appendix A
Inspection unit
Manufacturer
Ambient temperature
Calibration date
JJG771—2010
Target speed simulation device calibration record (recommended) format Model Specification
℃Relative humidity
Year Month Day
Calibrator
Factory number
Calibration location
Verifier
Nature of calibration: Initial calibration Port Subsequent calibration Port 1 In-use inspection
Port I port
Port II port
1 General technical requirements
Qualified port
Calibration of speed range
Speed value/(km/h)
Corresponding simulated speed Doppler
Frequency measurement value/Hz
Verification of speed error
Speed value/(km/h)
Corresponding simulated speed Doppler
Frequency theoretical value/Hz
Frequency measurement value/Hz
Actual frequency value/Hz
Frequency error/Hz
Speed error caused by frequency error
/(km/h）
Unqualified port
Verification of speed range and speed error
X-band
K-band port
Ka-band
Verification of frequency range
Verification of frequency error2. Adjust the frequency division multiple of the frequency divider and select the specified sampling time. Continuously sample the frequency signal, and the number of sampling groups m is 100.
Method 2: See Figure 1. Use a general counter (whose gate time can be adjusted arbitrarily) to measure the output frequency of the target speed simulation device and select the specified sampling time. Continuously sample the frequency signal, and the number of sampling groups m is 100. 2) Calculate the frequency stability of method 1 according to formula (3). ：p
?k2Mfao
(t+1 - t;)2
where: t, ti, T+1
JJG771—2010
are the average sampling time after frequency division, the sampling time value of the ith and ith tenth measurement, ms;
the number of measurement groups;
k2——unit conversion factor, kz=10-3:M——frequency division multiple of the frequency divider;
cycle multiplication (expansion) multiple.
3) Calculate the frequency stability of method 2 according to formula (4). ：g
（ff)2
faoN台
where: f, ft1——are the ith and ith tenth frequency measurement values, Hz. Its frequency stability shall meet the requirements of Article 4.2.2.2 of this Regulation. 6.3.4.3 Verification of 1h frequency fluctuation of target speed simulation device (4)
1) The frequency fluctuation verification block diagram is shown in Figure 1. The target speed simulation device outputs a frequency signal, and the speed verification points shall be selected at 3 points evenly distributed within the specified range (such as 20km/h, 100km/h and 200km/h, etc.).
2) The universal counter gate time is set to 10s, and the output frequency of the target speed simulation device is measured once every 5 minutes with the universal counter, for a total of 1h.
3) Calculate the frequency fluctuation S according to formula (5):
S=fa mx -fa min
Where: famax—--the maximum value of the frequency measured within 1h, Hz; famin—the minimum value of the frequency measured within 1h, Hz. Its frequency fluctuation shall meet the requirements of Article 4.2.2.3 of this Regulation. 6.3.4.4 Calculation of speed error
Calculate the speed error A according to formula (6):
A=2V++
Wherein: A
-speed error, km/h
speed error caused by frequency error, km/h, Ai=-2fao
speed error caused by frequency stability, km/h; △2=ou, where is the conversion factor between the square root of the Allan variance and the standard deviation; for the target speed simulation device using a crystal oscillator, take 2/3; for the target speed simulation device using an RC oscillator, take 1; α is determined by formula (3) or (4);
—-speed error caused by frequency fluctuation, km/h, A-speed value, km/h
The speed error shall comply with the requirements of Article 4.2.2 of this Regulation. S
6.3.5 According to the requirements of Article 6.3.3 and Article 6.3.4 of this Regulation, the frequencies corresponding to the X, K and Ka band speed calibration points of each of the two outputs of the target speed simulation device shall be calibrated, and the calibration results shall comply with the requirements of Article 4.2 of this Regulation.
6.4 Handling of calibration results
A calibration certificate shall be issued to the calibration device that has passed the calibration; a calibration result notice shall be issued to the calibration device that has failed the calibration, and the unqualified items shall be indicated.
Note: Reports can be issued separately for the microwave frequency counter and the target speed simulator. 6.5 Calibration cycle
The calibration cycle of the calibration device is 1 year. The calibration device must be recalibrated after maintenance. Appendix A
Inspection unit
Manufacturer
Ambient temperature
Calibration date
JJG771—2010
Target speed simulation device calibration record (recommended) format Model Specification
℃Relative humidity
Year Month Day
Calibrator
Factory number
Calibration location
Verifier
Nature of calibration: Initial calibration Port Subsequent calibration Port 1 In-use inspection
Port I port
Port II port
1 General technical requirements
Qualified port
Calibration of speed range
Speed value/(km/h)
Corresponding simulated speed Doppler
Frequency measurement value/Hz
Verification of speed error
Speed value/(km/h)
Corresponding simulated speed Doppler
Frequency theoretical value/Hz
Frequency measurement value/Hz
Actual frequency value/Hz
Frequency error/Hz
Speed error caused by frequency error
/(km/h）
Unqualified port
Verification of speed range and speed error
X-band
K-band port
Ka-band
Verification of frequency range
Verification of frequency error2. Adjust the frequency division multiple of the frequency divider and select the specified sampling time. Continuously sample the frequency signal, and the number of sampling groups m is 100.
Method 2: See Figure 1. Use a general counter (whose gate time can be adjusted arbitrarily) to measure the output frequency of the target speed simulation device and select the specified sampling time. Continuously sample the frequency signal, and the number of sampling groups m is 100. 2) Calculate the frequency stability of method 1 according to formula (3). ：p
?k2Mfao
(t+1 - t;)2
where: t, ti, T+1
JJG771—2010
are the average sampling time after frequency division, the sampling time value of the ith and ith tenth measurement, ms;
the number of measurement groups;
k2——unit conversion factor, kz=10-3:M——frequency division multiple of the frequency divider;
cycle multiplication (expansion) multiple.
3) Calculate the frequency stability of method 2 according to formula (4). ：g
（ff)2
faoN台
where: f, ft1——are the ith and ith tenth frequency measurement values, Hz. Its frequency stability shall meet the requirements of Article 4.2.2.2 of this Regulation. 6.3.4.3 Verification of 1h frequency fluctuation of target speed simulation device (4)
1) The frequency fluctuation verification block diagram is shown in Figure 1. The target speed simulation device outputs a frequency signal, and the speed verification points shall be selected at 3 points evenly distributed within the specified range (such as 20km/h, 100km/h and 200km/h, etc.).
2) The universal counter gate time is set to 10s, and the output frequency of the target speed simulation device is measured once every 5 minutes with the universal counter, for a total of 1h.
3) Calculate the frequency fluctuation S according to formula (5):
S=fa mx -fa min
Where: famax—--the maximum value of the frequency measured within 1h, Hz; famin—the minimum value of the frequency measured within 1h, Hz. Its frequency fluctuation shall meet the requirements of Article 4.2.2.3 of this Regulation. 6.3.4.4 Calculation of speed error
Calculate the speed error A according to formula (6):
A=2V++
Wherein: A
-speed error, km/h
speed error caused by frequency error, km/h, Ai=-2fao
speed error caused by frequency stability, km/h; △2=ou, where is the conversion factor between the square root of the Allan variance and the standard deviation; for the target speed simulation device using a crystal oscillator, take 2/3; for the target speed simulation device using an RC oscillator, take 1; α is determined by formula (3) or (4);
—-speed error caused by frequency fluctuation, km/h, A-speed value, km/h
The speed error shall comply with the requirements of Article 4.2.2 of this Regulation. S
6.3.5 According to the requirements of Article 6.3.3 and Article 6.3.4 of this Regulation, the frequencies corresponding to the X, K and Ka band speed calibration points of each of the two outputs of the target speed simulation device shall be calibrated, and the calibration results shall comply with the requirements of Article 4.2 of this Regulation.
6.4 Handling of calibration results
A calibration certificate shall be issued to the calibration device that has passed the calibration; a calibration result notice shall be issued to the calibration device that has failed the calibration, and the unqualified items shall be indicated.
Note: Reports can be issued separately for the microwave frequency counter and the target speed simulator. 6.5 Calibration cycle
The calibration cycle of the calibration device is 1 year. The calibration device must be recalibrated after maintenance. Appendix A
Inspection unit
Manufacturer
Ambient temperature
Calibration date
JJG771—2010
Target speed simulation device calibration record (recommended) format Model Specification
℃Relative humidity
Year Month Day
Calibrator
Factory number
Calibration location
Verifier
Nature of calibration: Initial calibration Port Subsequent calibration Port 1 In-use inspection
Port I port
Port II port
1 General technical requirements
Qualified port
Calibration of speed range
Speed value/(km/h)
Corresponding simulated speed Doppler
Frequency measurement value/Hz
Verification of speed error
Speed value/(km/h)
Corresponding simulated speed Doppler
Frequency theoretical value/Hz
Frequency measurement value/Hz
Actual frequency value/Hz
Frequency error/Hz
Speed error caused by frequency error
/(km/h）
Unqualified port
Verification of speed range and speed error
X-band
K-band port
Ka-band
Verification of frequency range
Verification of frequency error5 Calibration cycle
The calibration cycle of the calibration device is 1 year. The calibration device must be recalibrated after maintenance. Appendix A
Inspection unit
Manufacturer
Ambient temperature
Calibration date
JJG771—2010
Target speed simulation device calibration record (recommended) format
℃Relative humidity
Year, month, day
Calibrator
Factory number
Calibration location
Verifier
Nature of calibration: First calibration Port Subsequent calibration Port 1 In-use inspection
Port I port
Port II port
1 General technical requirements
Qualified port
Calibration of speed range
Speed value/(km/h)
Corresponding simulated speed Doppler
Frequency measurement value/Hz
Verification of speed error
Speed value/(km/h)
Corresponding simulated speed Doppler
Frequency theoretical value/Hz
Frequency measurement value/Hz
Actual frequency value/Hz
Frequency error/Hz
Speed error caused by frequency error
/(km/h）
Unqualified port
Verification of speed range and speed error
X-band
K-band port
Ka-band
Verification of frequency range
Verification of frequency error5 Calibration cycle
The calibration cycle of the calibration device is 1 year. The calibration device must be recalibrated after maintenance. Appendix A
Inspection unit
Manufacturer
Ambient temperature
Calibration date
JJG771—2010
Target speed simulation device calibration record (recommended) format
℃Relative humidity
Year, month, day
Calibrator
Factory number
Calibration location
Verifier
Nature of calibration: First calibration Port Subsequent calibration Port 1 In-use inspection
Port I port
Port II port
1 General technical requirements
Qualified port
Calibration of speed range
Speed value/(km/h)
Corresponding simulated speed Doppler
Frequency measurement value/Hz
Verification of speed error
Speed value/(km/h)
Corresponding simulated speed Doppler
Frequency theoretical value/Hz
Frequency measurement value/Hz
Actual frequency value/Hz
Frequency error/Hz
Speed error caused by frequency error
/(km/h）
Unqualified port
Verification of speed range and speed error
X-band
K-band port
Ka-band
Verification of frequency range
Verification of frequency error
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