JJF 1958-2021 English PDFUS$639.00 · In stock
Delivery: <= 5 days. True-PDF full-copy in English will be manually translated and delivered via email. JJF 1958-2021: Calibration Specification for Cesium Atomic Frequency Standards Status: Valid
Basic dataStandard ID: JJF 1958-2021 (JJF1958-2021)Description (Translated English): Calibration Specification for Cesium Atomic Frequency Standards Sector / Industry: Metrology & Measurement Industry Standard Classification of Chinese Standard: A57 Word Count Estimation: 28,236 Issuing agency(ies): State Administration for Market Regulation JJF 1958-2021: Calibration Specification for Cesium Atomic Frequency Standards---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order.Calibration Specification for Cesium Atomic Frequency Standards National Metrology Technical Specification of the People's Republic of China Caesium Atomic Frequency Standard Calibration Specification Published on 2021-12-28 2022-06-28 Implementation Released by the State Administration for Market Regulation Caesium Atomic Frequency Standard Calibration Specification Replacing JJG492-2009 Focal Point. National Time and Frequency Measurement Technical Committee Main drafting unit. China Institute of Metrology Participating in the drafting unit. Beijing Radio Measurement and Testing Institute Beijing University National Defense University This specification entrusts the National Time and Frequency Measurement Technical Committee to be responsible for the interpretation The main drafters of this specification. Zhang Aimin (China Institute of Metrology) Wang Yuzhuo (China Institute of Metrology) Liu Nianfeng (China Institute of Metrology) Participating drafters. Yang Jun (Beijing Radio Measurement and Testing Institute) Liu Dan (Beijing Radio Measurement and Testing Institute) Wang Yanhui (Peking University) Sun Guangfu (National University of Defense Technology) Table of contentsIntroduction (Ⅱ) 1 Scope(1) 2 References (1) 3 Overview(1) 4 Metrology Characteristics(2) 4.1 Output frequency and amplitude(2) 4.2 Harmonic and non-harmonic distortion(2) 4.3 Frequency Stability(2) 4.4 Phase noise(2) 4.5 Relative frequency deviation(3) 4.6 Frequency Reproducibility(3) 4.7 Frequency adjustment range(3) 4.8 second pulse (1PPS) output(3) 4.9 Clock Synchronization Deviation(3) 5 Calibration Conditions(3) 5.1 Environmental conditions (3) 5.2 Measurement standards and other equipment(3) 6 Calibration items and calibration methods (4) 6.1 Calibration items(4) 6.2 Calibration method(5) 7 Expression of calibration results (9) 8 Recalibration interval (10) Appendix A Raw Record Format(11) Appendix B Calibration Certificate (Inner Page) Format (14) Appendix C Example of Uncertainty Evaluation of Main Calibration Items (17)IntroductionThis specification is based on JJF 1071-2010 "Rules for Compilation of National Metrology Calibration Specifications" and JJF 1059.1-2012 "Measurement Uncertainty Evaluation and Representation" written. This specification is a revision of JJG492-2009 "Cesium Atomic Frequency Standard". Except for editorial changes, the main technical The changes are as follows. ---According to JJG2007-2015 "Time and Frequency Measuring Instruments", the frequency accuracy is changed to relative frequency deviation; --- Increase the calibration content of reproducibility, second pulse jitter, second pulse phase adjustment range and resolution; --- Delete Appendix A (the principles of two frequency standard comparators) in the original regulations. Previous releases of this specification. ---JJG492-1987; ---JJG492-2009. Caesium Atomic Frequency Standard Calibration Specification1 ScopeThis specification applies to the calibration of cesium atomic frequency standards.2 Reference documentsThis specification references the following documents. JJF 1001-2011 General Metrology Terms and Definitions JJF 1180 Terms and Definitions of Time and Frequency Measurement JJF 1206-2018 Specification for remote calibration of time and frequency standards JJG2007-2015 Time and frequency measuring instruments For dated references, only the dated version applies to this specification; for undated references The latest version (including all amendments) applies to this specification.3 OverviewThe cesium atomic frequency standard (hereinafter referred to as the cesium frequency standard) is a passive atomic frequency standard. The basic principle is shown in Figure 1.The physical part is mainly a cesium atom resonator, and the cesium atom in the resonator is The energy level transition occurs under the action of the microwave excitation signal, and the frequency discrimination signal corresponding to the transition frequency of the cesium atom is output; the electronic part It is mainly composed of signal demodulation, frequency control, crystal oscillator, signal modulation, frequency synthesis and other parts. The frequency of the oscillator is locked to the transition frequency of the cesium atom. The crystal oscillator output frequency has the same level of phase as the atomic transition frequency. For the frequency deviation and long-term stability characteristics, the output signal of the cesium frequency standard is generated after distribution and other processing, for external use. use. Fig.1 Basic working principle of cesium atomic frequency standard The cesium frequency standard with second pulse (1PPS) output is also called cesium atomic clock or cesium clock, which is widely used in time-frequency, communication Information, navigation, aerospace, national defense and other scientific research, measurement fields. ......Tips & Frequently Asked Questions:Question 1: How long will the true-PDF of JJF 1958-2021_English be delivered?Answer: Upon your order, we will start to translate JJF 1958-2021_English as soon as possible, and keep you informed of the progress. The lead time is typically 3 ~ 5 working days. The lengthier the document the longer the lead time.Question 2: Can I share the purchased PDF of JJF 1958-2021_English with my colleagues?Answer: Yes. 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