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Review of Research Advance on Cold-atom Gravimeter BAI Jin-hai, MA Hui-juan, HU Dong, WANG Yu Journal of Astronautic Metrology and Measurement    2023, 43 (5): 1-10.   DOI: 10.12060/j.issn.1000-7202.2023.05.01 Abstract （197）      PDF（pc） （4579KB）（2645）       Knowledge map    Save The cold atom gravimeter uses laser cooling,atomic interference manipulation,and other technologies to achieve absolute gravity acceleration measurement.It is a new type of quantum sensor that has developed rapidly over the [JP2]past three decades.Currently,its measurement sensitivity has exceeded that of traditional laser interference absolute gravimeters,and the measurement uncertainty has reached the same level.In metrology traceability,basic scientific research,geophysics,resource exploration,autonomous navigation and other aspects have important application value.Analyzes the principle of cold atom gravimeters,introduces the research progress and development trend of cold atom gravimeters,and analyzes and combs the research direction of cold atom gravimeters,especially the key points in dynamic application scenarios. Related Articles | Metrics | Comments（0）

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Quantum Precision Measurement Technology and Its Typical Applications in Measurement Field GE Meng, ZHANG Tie-li, LIU Hao, SONG Yan, WU Chen Journal of Astronautic Metrology and Measurement    2023, 43 (6): 1-6.   DOI: 10.12060/j.issn.1000-7202.2023.06.01 Abstract （313）      PDF（pc） （4203KB）（1650）       Knowledge map    Save Quantum precision measurement is based on the basic principle of quantum mechanics by using the interaction between light，atoms and magnetic field to measure physical quantities.The concept of quantum precision measurement and the technical principles in quantum precision measurement are described as a starting point,and typical applications of quantum precision measurement technology in the field of measurement are investigated.The principles,applications,and development status of femtosecond optical frequency comb technology,precision measurement technology for atomic ensemble and quantum light field,and quantum enhancement measurement technology based on nonlinear interference are analyzed.It could provide reference for the development of measurement technology in China. Related Articles | Metrics | Comments（0）

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Design of Portable Telecontrol Telemetry and Data Transmission Test Equipment Based on ADRV9009 ZHANG De-zhi, LI Jin-long, SONG Zhao-han Journal of Astronautic Metrology and Measurement    2023, 43 (4): 75-80.   DOI: 10.12060/j.issn.1000-7202.2023.04.12 Abstract （63）      PDF（pc） （2756KB）（1018）       Knowledge map    Save The commonly used TT&C test equipment adopts a standardized case with a shelf structure,which has problems such as large size,heavy weight,difficult disassembly,and inconvenient to field test.To solve these problems,a portable telecontrol telemetry and data transmission test equipment based on Zynq7100+ADRV9009 is designed.The design architecture,hardware scheme and software configuration flow of the equipment are given,and the wireless transmission link is reviewed.The results of system test show that the portable TT&C equipment has the characteristics of small volume,light weight and stable operation,and can meet the requirements of aircraft telecontrol telemetry and data transmission links field test. Related Articles | Metrics | Comments（0）

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Review of Dynamic Data Processing Methods for Engine Test LIU Zi-xing, Gao Jun, SONG Jiong-liang, LIN Meng, YANG Yi Journal of Astronautic Metrology and Measurement    2023, 43 (4): 66-74.   DOI: 10.12060/j.issn.1000-7202.2023.04.11 Abstract （59）      PDF（pc） （1466KB）（736）       Knowledge map    Save Engine test dynamic data usually contains important information such as vibration and pulsating pressure of key parts,which is an important reference index for evaluating engine performance,component characteristics and optimal design.The advantages and disadvantages of several methods suitable for dynamic data processing are summarized,such as fast Fourier transform,wavelet analysis,wavelet packet analysis,Hilbert-Huang transform,and the application of these methods and their combination in dynamic data analysis and processing are introduced. Related Articles | Metrics | Comments（0）

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Overview of Magnetic Measurement Development Based on Quantum Measurement Technology LI Xiaofang, CHENG Huafu, BAO Zhong, WANG Dongping, ZHANG Feng Journal of Astronautic Metrology and Measurement    2024, 44 (1): 7-13.   DOI: 10.12060/j.issn.1000-7202.2024.01.02 Abstract （53）      PDF（pc） （743KB）（680）       Knowledge map    Save Aiming at the development history of magnetic quantum measurement technology and the capacity of magnetic quantum metrology standards established based on quantum magnetometers in various countries,proton magnetometers,Nuclear Magnetic Rsonance(NMR) magnetometers,and optical pump magnetometers that have been applied to magnetic quantum metrology standards is studied;Presenting the principles of quantum magnetometers such as CPT magnetometer,SERF magnetometer,diamond NV color-center magnetometer;By summarizing the domestic and international development status of quantum magnetometers with high accuracy,low magnetic field noise and good stability tandards,analyzing the easibility and advantages of replacing the current magnetic parameter metrology standards by using the technical characteristics of various quantum magnetometers;It proposes the potential research direction of quantum measurement technology in the quantization of magnetic measurement standards in the future. Related Articles | Metrics | Comments（0）

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Development Status and Metrology Prospect of Terahertz Quantum Correlation Imaging and Quantum Dot Detector LI Hong-guang, WANG Yuan-bo, LIAO Wen-tao Journal of Astronautic Metrology and Measurement    2023, 43 (5): 41-46.   DOI: 10.12060/j.issn.1000-7202.2023.05.06 Abstract （96）      PDF（pc） （2451KB）（650）       Knowledge map    Save The cross research between quantum technology and cutting-edge disciplines such as terahertz technology has led to the emergence of disruptive new system devices such as terahertz quantum correlation cameras and quantum dot detectors,expanding the space for new quality and new domain defense applications.Compared to traditional imaging technology,terahertz quantum correlation imaging based on quantum technology exhibits unique advantages in imaging speed,imaging resolution,and other aspects.The terahertz quantum correlation imaging system is based on terahertz emission sources,detection systems,masks,algorithms,etc.,achieving compression sensing,time resolution,Fourier transform,and other imaging technologies.In addition,a review was conducted on terahertz quantum correlation imaging systems and quantum dot detectors,and corresponding research on terahertz quantum correlation imaging and measurement calibration technology of terahertz quantum dot detectors was explored.By proposing metrological problems and solutions,which provides the application prospects of terahertz quantum detection and imaging metrology technology. Related Articles | Metrics | Comments（0）

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Atom-based Vector Microwave Electrometry via Electromagnetic Induction Transparency and Autler-Townes Splitting in Cold Rydberg Atoms LIU Xiu-bin, JIA Feng-dong, ZHOU Fei, YU Yong-hong, ZHANG Jian, XIE Feng, ZHONG Zhi-ping Journal of Astronautic Metrology and Measurement    2023, 43 (3): 5-10.   DOI: 10.12060/j.issn.1000-7202.2023.03.02 Abstract （72）      PDF（pc） （1127KB）（546）       Knowledge map    Save Utilizing the advantages of low temperature of cold atoms, narrow spectral peaks of Rydberg Electromagnetic Induction Transparency (EIT), and clear atomic quantum states. The polarization of the microwave can be measured directly through spectral intervals in cold atomic samples based on Rydberg EIT and Autler-Townes (AT) splitting. The results show that the splitting interval of the Rydberg EIT-AT varies monotonously with the polarization of the microwave electric field and is proportional to the projection of the polarization of the microwave electric field on the polarization direction of the probe laser. The resolution is 3.2 °. Compared with the traditional method of using EIT resonance to detect the change of light transmittance in the hot atom vapor cell, the method based on cold atom EIT-AT splitting interval has the advantages of more direct, accurate and simple analysis. This work is of great significance to the absolute measurement of microwave polarization and the calibration of electric field strength. Related Articles | Metrics | Comments（0）

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Precision Measurement and Application of Quantum Interference Based on Compressed Light and Entangled Light ZHANG Yong-chao, ZHANG Tie-li, GAO Xiao-qiang, LIU Xiao-xu, XU Yong-yao Journal of Astronautic Metrology and Measurement    2023, 43 (6): 25-30.   DOI: 10.12060/j.issn.1000-7202.2023.06.05 Abstract （112）      PDF（pc） （3194KB）（443）       Knowledge map    Save Quantum precision measurement technology has shown broad application prospects in many fields due to its advantage of breaking through the standard quantum limit (SQL).The basic principles of quantum interferometry based on compressed and entangled light were introduced,mainly including the principles of Hong Ou Mandel (HOM) interferometry and Mach Zehnder (MZ) interferometry.This article summarizes the main application directions of quantum interferometry technology at present,including applications in the simultaneous measurement of small displacement and angle multiple parameters,gravitational wave measurement,gas concentration detection,and quantum imaging.It looks forward to the future development and application prospects of quantum precision measurement technology,and analyzes the current problems and future development trends. Related Articles | Metrics | Comments（0）

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Research Progress of High-precision Autonomous Navigation Based on Cold Atom XIE Hong-tai, KANG Ze-hao, HU Dong, WANG Yu Journal of Astronautic Metrology and Measurement    2023, 43 (6): 31-38.   DOI: 10.12060/j.issn.1000-7202.2023.06.06 Abstract （108）      PDF（pc） （3238KB）（434）       Knowledge map    Save All-weather,high anti-interference,and high concealment positioning,navigation and timing without exchanging information with the outside world can be achieved by autonomous navigation.Cold atom interferometry is with ultra-high sensitivity and stability due to its characteristics of matter wave and absolute measurement,and is expected to create an autonomous high-precision navigation system integrating inertial navigation,gravity and gravity gradient map matching aided navigation,and applied to long-term voyage carriers.Based on the configuration of atom interferometry,the research on cold atom sensors in recent decades over the world is summarized,and the technical schemes is analyzed,so as the selection of schemes suitable for the autonomous navigation is provided. Related Articles | Metrics | Comments（0）

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Development Trend of High Performance Passive CPT Atomic Clock  DING Chen-feng, CHEN Hai-jun Journal of Astronautic Metrology and Measurement    2023, 43 (5): 23-30.   DOI: 10.12060/j.issn.1000-7202.2023.05.03 Abstract （98）      PDF（pc） （1126KB）（364）       Knowledge map    Save The use of a single circularly polarized light configuration to achieve a CPT state will generate a polarized dark state,resulting in a lower contrast of the CPT signal.Therefore,the frequency stability index of traditional CPT atomic clocks is not high.In order to improve the contrast of CPT signals and improve the performance of CPT atomic clocks,various schemes for eliminating polarized dark states have been proposed and studied.These schemes can be divided into parallel line polarized light configurations and phase delayed configurations based on the polarization state and generation method of the laser used σ+-σ- Configuration,push-pull pump configuration,vertically polarized light configuration,polarization modulation configuration.Based on the principles and development level of these schemes,a comparative analysis of their advantages,disadvantages,and improvement plans can be conducted to explore new development directions for high-performance atomic clocks under different demand conditions. Related Articles | Metrics | Comments（0）

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Thermometry based on Nitrogen-vacancy Centers in Diamonds DONG Xian-qi, LIU Yan, YANG Ren-fu Journal of Astronautic Metrology and Measurement    2023, 43 (3): 56-60.   DOI: 10.12060/j.issn.1000-7202.2023.03.11 Abstract （68）      PDF（pc） （1210KB）（362）       Knowledge map    Save In recent years, the rapid development of quantum information science has promoted the research of various quantum sensing technologies and produced many important results, which has had an important impact in the field of precision measurement. The sensing technology based on solid-state diamond NV color center electronic spin detection can be traced back to the basic quantum physical principles, and has important research value in the measurement standards of various sensing fields such as magnetic field, electric field, temperature, and pressure. The excellent properties of diamond NV color centers make reliable, stable and high-precision sensing applications possible in harsh environments. Taking its application in the field of temperature measurement as an example, this paper focuses on the development of NV color center spin detection principles and methods in the past ten years, and discusses the important research significance of solid-state quantum temperature measurement in combination with the latest research results. Related Articles | Metrics | Comments（0）

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Research Progress on Calibration Technology of Single Photon Detectors LIU Chang-ming, ZHANG Peng-ju, LIN Yong-jie, SHEN Rong-ren, LIU Hong-bo, SHI Xue-shun, ZHUANG Xin-gang, WU Bin Journal of Astronautic Metrology and Measurement    2023, 43 (3): 34-39.   DOI: 10.12060/j.issn.1000-7202.2023.03.07 Abstract （81）      PDF（pc） （1028KB）（358）       Knowledge map    Save With the rapid development of quantum information technology,single photon detectors,as core devices in fields such as quantum secure communication,have been one of the research hotspots.In recent years,the performance of single photon detectors has greatly improved with the development of various new technologies.At the same time,the research on testing and calibration techniques of single photon detectors has also received attention,especially the new calibration technology based on quantum physical effects,which have received attention from various metrological institutions.A brief introduction is given to the working mechanism of single photon detectors and the research progress of calibration technology of single photon detectors at home and abroad.The current status of detection efficiency calibration based on standard detectors and correlated photon pairs,as well as calibration technology for after-pulse probability and time jitter,is summarized.This can provide reference for researchers in related fields and put forward prospects for the future development of technology. Related Articles | Metrics | Comments（0）

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Method for Analyzing Uncertainty of High Precision Ultrasonic Flowmeter for Main Feedwater LIU Yan, WEI Hua-tong, BAI Tian, WANG Feng-ning, REN Da-cheng, LIU Li, CUI Xi-wei, GUO Lin Journal of Astronautic Metrology and Measurement    2023, 43 (4): 1-7.   DOI: 10.12060/j.issn.1000-7202.2023.04.01 Abstract （101）      PDF（pc） （994KB）（330）       Knowledge map    Save The methodology of high-precision measurement of main feedwater flow is proposed based on Hualong No.1 and other nuclear power plants(NPP) to achieve measurement uncertainty recapture power uprates(MUR).The components of uncertainty measured by ultrasonic flowmeter such as calibration coefficient and medium density are quantified.Under the conditions with defining the structure and measurement principle of ultrasonic flowmeter and the complex operating conditions of high pressure and high temperature(HPHT),the uncertainty evaluation methodology of channel geometric factor and pipe cross-sectional area has been given respectively.By analyzing the influence of the operating conditions on the flow measurement,the uncertainty introduced by the flow field velocity has been evaluated.The analysis results indicate that the metrological traceability method which based on the combination of several uncertainty evaluation methods is feasible. Related Articles | Metrics | Comments（0）

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Research on Gas Temperature Measurement Based on Dual-comb Spectroscopy Technology GAO Xiao-qiang, LIU Hao, ZHANG Zhi-tao, Wu Wei-wei Journal of Astronautic Metrology and Measurement    2023, 43 (6): 12-16.   DOI: 10.12060/j.issn.1000-7202.2023.06.03 Abstract （148）      PDF（pc） （2609KB）（326）       Knowledge map    Save As a new technology,dual-comb spectroscopy has the advantages of high resolution,high sensitivity,wide spectral coverage and high speed measurement,which has unique advantages and broad development prospects in the field of molecular precision spectral analysis.A high temperature gas measurement scheme based on dual-comb spectrum is proposed.Two combs with small refrequency difference are used to achieve high temperature gas absorption spectrum measurement with high precision through asynchronous sampling,and the spectral temperature inversion algorithm is used to obtain the gas temperature value.In the experiment,a dual-comb system with repetition rate of about 205.315 MHz and 205.365 MHz was used to achieve high precision measurement of the absorption spectrum of CO2 gas at 1 057 K at a wavelength of 4.2 μm.The results show that,as an active temperature measurement technology,it has the ability of accurate measurement of high temperature gas,and has an important application prospect in the field of high temperature measurement of national defense equipment. Related Articles | Metrics | Comments（0）

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A Review of Progress in Miniaturization of Cold Atom Quantum Vacuum Measurement Devices CHENG Yong-jun, DONG Meng, SUN Wen-jun, WU Xiang-min, ZHANG Ya-fei Journal of Astronautic Metrology and Measurement    2023, 43 (6): 17-24.   DOI: 10.12060/j.issn.1000-7202.2023.06.04 Abstract （122）      PDF（pc） （7384KB）（317）       Knowledge map    Save Quantum vacuum measurement is an important development direction of vacuum measurement technology in the future.Based on intrinsic physical properties of matter,quantum vacuum measurement has the characteristics of no calibration,little disturbance to vacuum environment and high precision.Currently,laboratory-scale cold atom quantum vacuum measuring devices have shown excellent performance,and scientists are working hard to advance the practical application of quantum sensors,which means that cold atom quantum vacuum measuring devices must be transformed from large laboratory-scale platforms to compact miniaturization quantum sensors.This requires miniaturization quantum sensors to have both a small size and excellent performance under extreme dynamic conditions.The latest advances in cold atom quantum sensor miniaturization is presented,focusing on the key components required for atomic cooling,including laser systems,atomic sources,magneto-optical traps,and coils.The miniaturization scheme of each element and its influence on the sensor performance is discussed,and the development of cold atom quantum vacuum sensor is prospected. Related Articles | Metrics | Comments（0）

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Influence of Reference Azimuth Error on Aiming Accuracy of Chinese New Generation Launch Vehicle#br# QI Ying-hong, CHEN Xiu-ping, GUO Jin-gang, GUO Zhen, SONG Jing Journal of Astronautic Metrology and Measurement    2023, 43 (6): 59-62.   DOI: 10.12060/j.issn.1000-7202.2023.06.11 Abstract （75）      PDF（pc） （938KB）（317）       Knowledge map    Save A short-distance optical aiming method is used for Chinese new generation launch vehicle,which the photoelectric theodolite is located on the launch tower close to the vehicle.Because of the launch tower’s sloshing,there is error of the reference azimuth used by the theodolite.According to the method of optical vector,the effect model of the reference azimuth error to the aiming error is established.The results of numerical simulation demonstrate the aiming infrastructure should be satisfied a certain degree of stability. Related Articles | Metrics | Comments（0）

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High-performance Miniaturised Software Radio Transceiver System Based on ADRV9009 XU Jianxiang, ZHOU Changyi, LIU Ruipeng, JIANG Yaxiang, ZHOU Li Journal of Astronautic Metrology and Measurement    2024, 44 (3): 41-47.   DOI: 10.12060/j.issn.1000-7202.2024.03.07 Abstract （54）      PDF（pc） （4605KB）（301）       Knowledge map    Save To address issues such as the complexity of hardware structure,narrow bandwidth,poor flexibility,and limited scalability in traditional radio transceiver systems,a design and implementation method for a software-defined radio transceiver system based on the high-performance transceiver ADRV9009 and Kintex-7 FPGA is proposed.This high-performance software-defined radio transceiver system primarily consists of three main parts:a high-bandwidth RF unit,a digital signal processing unit,and peripheral units.It allows flexible configuration of transmission and reception parameters such as frequency points and bandwidth,exhibiting excellent RF performance.Compared to traditional software-defined radio platforms,it features small size,strong flexibility and scalability,and versatile application scenarios,making it promising for widespread use in mobile communication,satellite communication,and other fields. Related Articles | Metrics | Comments（0）

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Research on Automatic Calibration Software for Various Types S Parameter of Microwave Devices based on Network Analyzer ZHANG Ping, MAO Li-yong, MA Yi-wei, ZHENG Han-zhi Journal of Astronautic Metrology and Measurement    2023, 43 (3): 66-71.   DOI: 10.12060/j.issn.1000-7202.2023.03.13 Abstract （55）      PDF（pc） （1399KB）（298）       Knowledge map    Save With the aim to achieve efficient measurement and reduce the complexity of measurement parameter settings caused by various types of devices under test, this paper designs the S-parameter automatic calibration software with multi-thread and modular structure of C# by analyzing the working principle and performance characteristics of the microwave network S-parameter measurement system. The S-parameter automatic calibration software establishes the database in various types of devices under test, the parameter of standard parts and the test flow of the S-parameter measurement system. The software also establishes the measurement uncertainty model of the measured parameter. The reflection parameter and transmission parameter can be tested by using vector network analyzer with automatic calibration software. It can be found that the test results of automatic calibration software are in high consistency with those of manual test through experiments. Related Articles | Metrics | Comments（0）

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Recent Progress and Applications on Fiber-based Optical Frequency Comb LI Haonan, CHEN Xinyi, YANG Honglei, GE Jun Journal of Astronautic Metrology and Measurement    2024, 44 (3): 1-10.   DOI: 10.12060/j.issn.1000-7202.2024.03.01 Abstract （117）      PDF（pc） （2545KB）（297）       Knowledge map    Save Invented at the turn of the century,Optical frequency comb has coherently bridged between radio frequencies and optical frequencies.With more than 20-years continuous development,optical frequency comb has revolutionized optical frequency measurement methods and been widely used in precision measurement beyond that.Firstly,the advantages of the fiber optical frequency comb are highlighted,and the technical principle of the fiber optical frequency comb is briefly introduced.Then,the main development directions of the fiber optical frequency comb,namely low noise,high power,and integration,are analyzed.Finally,the application progress of the fiber optical frequency comb in optical frequency measurement,absolute distance measurement,ultra-low noise microwave generation,precise spectral measurement,and astronomical spectral calibration are discussed. Related Articles | Metrics | Comments（0）

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Research on Quantum DC Nanovolt Voltage Standard based on Programable Josephson Voltage Standard ZHU Zhu, KANG Yan, ZHANG Li-dan, HU Yi-fei Journal of Astronautic Metrology and Measurement    2023, 43 (3): 21-25.   DOI: 10.12060/j.issn.1000-7202.2023.03.05 Abstract （65）      PDF（pc） （2707KB）（294）       Knowledge map    Save This paper introduces the quantum DC nanovoltage standard.It includes basic principle,composition of the standard,implementation plan,and measurement dada.the quantum DC nanovoltage standard is based on AC Josephson effect.It utilizes differential principle which is based on programmable Josephson DC voltage standard to generate nanovoltage.The paper proposed a basic plan and an improved design plan,further enhancing the performance of the standard.The quantum DC nanovoltage standard is able to provide high precision quantum DC nanovoltage signals,which not only provides a new means for precise measurement of DC voltage,but also solves the problem of nanovoltage traceability. Related Articles | Metrics | Comments（0）

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Research of Low Cost and High Integration for Launch Control System WANG Xu, RONG Gang, CHANG Xi, JIANG Yue, MAI Ji Journal of Astronautic Metrology and Measurement    2023, 43 (6): 76-82.   DOI: 10.12060/j.issn.1000-7202.2023.06.14 Abstract （82）      PDF（pc） （3144KB）（284）       Knowledge map    Save The design of the measuring,launching and control system of the vehicle is directly related to the efficiency and reliability of ground data transmission.A general low cost,high integration,integration system is proposed,which can realize real-time and post-hoc analysis and interpretation of test data while ensuring efficient transmission of time sequence instructions and telemetry data such as test power supply and distribution over long distances.Receiving the data on the aircraft，the fault detection,health status assessment,life and data management of the aircraft are completed by the ground measurement and control software.The system functions and software implementation methods are integrated to simplify the system architecture.The system development and maintenance costs are reduced,and the integration,reliability and maintenance of the system are improved. Related Articles | Metrics | Comments（0）

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Research Progress on Graphene Sensor and Quantum Dots DONG Jun-wei, LU Yi, LIU Xia, GUO Guo-jian, YOU Xin-ran, WANG Wei, TAO Wei, WANG Ze-xi Journal of Astronautic Metrology and Measurement    2023, 43 (5): 47-51.   DOI: 10.12060/j.issn.1000-7202.2023.05.07 Abstract （72）      PDF（pc） （1703KB）（271）       Knowledge map    Save As a new type of two-dimensional material in the 21st century,graphene has very few lattice defects and has the characteristics of zero band gap.Based on the unique electrical performance of graphene,it has extremely high sensitivity in the field of sensing.By controlling the physical size of the graphene,the obtained graphene quantum dot(GQDS) has the advantages of optical lighting,low toxicity,and luminous adjustment,and plays an important role in fluorescent imaging,drug treatment,and biosensing.Based on the excellent characteristics of graphene as a sensor and quantum dot,some applications of graphene in the quantum field are summarized,and the future development direction of graphene is outlook. Related Articles | Metrics | Comments（0）

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Intercomparison of Environmental Nuclear Radiation Measuring GAO Fei, WANG Jing-qian, DONG Lu-qi, WANG Fei-fei Journal of Astronautic Metrology and Measurement    2023, 43 (5): 68-74.   DOI: 10.12060/j.issn.1000-7202.2023.05.11 Abstract （85）      PDF（pc） （776KB）（270）       Knowledge map    Save In order to check and promote the improvement of calibration ability and the technical ability of operators,and ensure the reliability of monitoring data,the measurement and comparison work of environmental nuclear radiation monitoring instrument was carried out.The intercomparison includes environmental level dosemeters, protection level dosemeters which coverage for environmental level,and γ-ray air kerma secondary standard ionization chamber.The intercomparison parameters involve air kerma and ambient dose equivalent.The intercomparison covers a wide range of environmental nuclear radiation monitoring instruments.X-ray response,γ-rays and cosmic rays response properties of the environmental nuclear radiation monitoring instruments were studied.The En value and relative error were compared to analyze and evaluate the results.As the intercomparison results,the En values of standard ionization chambers in calibration laboratory are less than 1,and all meet requirements.Most of the environmental radiation monitoring instruments meet the requirements of S-Cs measurement.However,the X-ray response of most monitoring instruments are poor.Some monitoring instrument cannot meet the requirements that the energy response variation limit dose not exceed ±30%,so it is recommended that the instrument user should verify its energy response during the first inspection. Related Articles | Metrics | Comments（0）

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A Review of Mid-infrared Gas Detection Technology Based on Quantum Precision Measurement ZHU Tianyi, FENG Dianying, XU Feng, DONG Yazhuo, ZHANG Wenshen, HOU Qianqian, LIU Xia, WANG Wei Journal of Astronautic Metrology and Measurement    2024, 44 (5): 16-24.   DOI: 10.12060/j.issn.1000-7202.2024.05.03 Abstract （143）      PDF（pc） （3020KB）（270）       Knowledge map    Save This article reviews mid-infrared gas detection technology based on quantum precision measurements.With the development of the semiconductor industry,the requirements for the purity of electronic process gases continue to increase.Traditional mid-infrared gas detection technology faces sensitivity and accuracy challenges in trace gas detection.This article analyzes in detail the characteristics,application status and limitations of technologies such as fiber evanescent waves,photoacoustic spectroscopy,Fourier transform infrared spectroscopy,tunable diode laser absorption spectroscopy and optical cavity ring-down spectroscopy,and focuses on the introduction of quantum correlation spectroscopy.Mid-infrared gas detection technology breaks through the performance bottleneck of traditional mid-infrared detectors by utilizing photon quantum detectors and frequency up-conversion technology,significantly improving detection sensitivity and signal-to-noise ratio.This technology will become a key research direction in the future and This technological breakthrough provides an important reference for achieving higher-precision trace gas detection. Related Articles | Metrics | Comments（0）

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Robustness Evaluation Methods of Models Based on Principal Component Analysis YU Tao, WANG Siye, ZHAO Zhongyuan Journal of Astronautic Metrology and Measurement    2024, 44 (6): 20-27.   DOI: 10.12060/j.issn.1000-7202.2024.06.03 Abstract （53）      PDF（pc） （713KB）（265）       Knowledge map    Save The rapid development of artificial intelligence has deeply penetrated various industries,with deep neural networks (DNN) being widely applied in multiple fields.However,the popularity of the application exposes the serious threat of adversarial attacks on the vulnerability of intelligent models.Adversarial attacks can lead to model failure,particularly in critical areas such as commercial and military security,potentially resulting in severe consequences.These attacks work by crafting carefully designed inputs to disrupt the normal functioning of models,thus compromising system security and reliability.To comprehensively and scientifically evaluate the robustness of different model algorithms,a quantitative evaluation framework is proposed based on Principal Component Analysis (PCA) for the first time,which encompasses several key evaluation metrics,including misclassification rate,imperceptibility,and attack efficiency.By testing over 20 model algorithms and using PCA to reduce the dimensionality of high-dimensional data,the main evaluation factors are extracted,simplifying the data structure and ultimately producing an overall score for each algorithm.Experimental results demonstrate that the proposed evaluation method is effective and reliable,providing scientific guidance for research on model robustness. Related Articles | Metrics | Comments（0）

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Revolution of Mass Quantum Metrology and Development of Watt Balance YANG Rong-qi, WANG Si-xian, WANG Xun Journal of Astronautic Metrology and Measurement    2023, 43 (6): 7-11.   DOI: 10.12060/j.issn.1000-7202.2023.06.02 Abstract （130）      PDF（pc） （1573KB）（264）       Knowledge map    Save The evolution of the definition of kilogram,the basic unit of SI,was discussed.The specific causes that drive the rapid realization of quantization of mass unit was clarified with the corresponding impact on mass metrology and electrical metrology.The internal logic of quantization of mass unit based on Avogadro constant and Planck constant was analyzed.The specific principle of establishing a relation between macroscopic mass and Planck constant by watt balance was discussed.The development and relative standard uncertainties of the measurement of watt balance in six institutions such as NPL,NIST and NIM was introduced.The data show that China has entered the international advanced level in the field of mass quantum metrology. Related Articles | Metrics | Comments（0）

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Faraday Lasers for Quantum Metrology Applications ZHANG Jia, SHI Hangbo, WANG Zhiyang, QIN Xiaomin, LIU Zijie, GUAN Xiaolei, GAO Xun, WANG Yu, SHI Tiantian, CHEN Jingbiao Journal of Astronautic Metrology and Measurement    2024, 44 (5): 1-7.   DOI: 10.12060/j.issn.1000-7202.2024.05.01 Abstract （105）      PDF（pc） （1823KB）（252）       Knowledge map    Save High-precision frequency-stabilized lasers are an important foundation and component for realizing the realization of quantum precision measurement.Faraday laser utilizes atomic filter for frequency selection,and the output wavelength is limited to the transmission spectrum near the atomic transition frequency,which has significant advantages such as automatic correspondence between wavelength and atomic spectral line,narrow linewidth,and resistance to laser diode current and temperature fluctuations.Faraday lasers have many applications in the field of quantum metrology,such as atomic clocks,atomic gravimeters,and atomic magnetometers.Starting from the research background and basic principle of Faraday lasers,we introduce the practical applications and important values of Faraday lasers in such fields as cesium atomic clock,atomic gravimeter,and optical communication are introduced.In the future,with the continuous maturity and innovation,Faraday lasers are expected to realize a wide range of applications in more fields,such as high-power laser weapons,Reedburg atomic radar,etc.,which are expected to play a greater role in the field of national defense and military industry measurement. Related Articles | Metrics | Comments（0）

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An 852 nm Frequency-stabilized Laser Based on the Ultrastable Cavity PDH Locking Technique#br# MA Jiyang, SHEN Tong, XUE Xiaobo, ZHAO Weinan, SU Yabei, YANG Honglei, ZUO Yani, ZHANG Shengkang Journal of Astronautic Metrology and Measurement    2024, 44 (3): 68-74.   DOI: 10.12060/j.issn.1000-7202.2024.03.11 Abstract （95）      PDF（pc） （2399KB）（246）       Knowledge map    Save Since the development of laser locking technology in the 1980s,ultrastable lasers have played an important role in high-precision optical quantum time-frequency metrology,such as optical clocks,gravitational wave detection,cavity quantum electrodynamics,and satellite-ground communication.The Pound-Drever-Hall(PDH) technology provides a good way to stabilize free running lasers.Here,by utilizing such method,we lock the 852 nm wavelength laser to the resonance frequency of the ultrastable cavity to achieve the highly-stabilized laser output.In the experiment,the quality factor of the ultrastable resonator reached 1010,the finesse reached 200,000,and the 1 second frequency stability of the output laser reached 5.2×10-15 with laser linewidth of 2.3 Hz.This continuous laser with such frequency stability will provide robust technical support for an 852 nm clock laser with good correlation with Cs atoms. Related Articles | Metrics | Comments（0）

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Study of Development and Current Status of Quantum References for Voltage ZHANG Jinkai, JIANG Zhu, HU Jiaxin, WANG Bing Journal of Astronautic Metrology and Measurement    2024, 44 (4): 1-10.   DOI: 10.12060/j.issn.1000-7202.2024.04.01 Abstract （159）      PDF（pc） （2181KB）（244）       Knowledge map    Save Centered on a discussion of the development of voltage quantum references and their current status,the Josephson effect，the resulting principles of Josephson junctions and Josephson junction arrays are expounded.The transition from traditional Josephson voltage references to programmable Josephson voltage references as the demand for measurements expands from DC to AC are described.The development history,research results,and applications of two important electrical metrology topics,namely,programmable voltage standards are focused on,based on binary division arrays and pulsedriven arrays,which are at the forefront of current research.Finally,the development of voltage quantum reference over the years is summarized and its future development direction is envisioned. Related Articles | Metrics | Comments（0）

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The Radar Development Trends based on Advanced Quantum Measurement Technology BAI Wen-hao, WU Ji, DU Yu, YANG Jian Journal of Astronautic Metrology and Measurement    2023, 43 (3): 11-15.   DOI: 10.12060/j.issn.1000-7202.2023.03.03 Abstract （32）      PDF（pc） （938KB）（242）       Knowledge map    Save The traditional radar scheme is based on electromagnetic wave signal transmission theory,target location and other parameters measurement are realized by detecting the electromagnetic wave echo signal reflected by objects in space.The quantum radar under the framework of quantum technology has more obvious advantages in improving radar accuracy,response speed,anti-jamming and anti-stealth compared with the traditional radar.The principle,development and application of quantum technology in radar are introduced in this paper,and three kinds of quantum radars based on advanced quantum measurement technology in china are introduced emphatically.By expounding the case and analyzing its principle,which provides a new idea for the further development of quantum radar in the future. Related Articles | Metrics | Comments（0）

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Research Progress on the Mercury Ion Trapped Microwave Clock WANG Nuan-rang, YI Hang, XUE Xiao-bo, ZHANG Sheng-kang Journal of Astronautic Metrology and Measurement    2023, 43 (5): 31-35.   DOI: 10.12060/j.issn.1000-7202.2023.05.04 Abstract （98）      PDF（pc） （4478KB）（236）       Knowledge map    Save The mercury ion trapped microwave clock utilizes a quadrupole trap to achieve ion trapping,and completes the preparation of mercury ion states through a mercury lamp,making it easy to integrate and miniaturize.Through the optimization and design of key components such as ion trap,mercury lamp and its optical path,the pump light emitted by the mercury lamp can fully interact with the ions trapped in the ion trap to complete the preparation of states.40.5 GHz microwave is transmitted to the center of the ion trap through the horn antenna to complete the inversion of the ion number.The transiting line of the trapped mercury ions is detected by a weak fluorescence detection system and the measured transiting line width is about 1 Hz.The closed-loop locking of mercury ion microwave clock is achieved by the servo loop control system.After experiment testing,the frequency stability index can reach 4E-13/τ(1 s≤τ≤1 000 s) and 7E-15 at 10 000 s. Related Articles | Metrics | Comments（0）

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Noise Suppression of Laser-pumped Cesium-Helium Optical Magnetometer FU Ji-qing, KONG Jia, CHENG Hua-fu Journal of Astronautic Metrology and Measurement    2023, 43 (5): 52-56.   DOI: 10.12060/j.issn.1000-7202.2023.05.08 Abstract （64）      PDF（pc） （1221KB）（234）       Knowledge map    Save This paper describes a laser-pumped cesium-helium magnetometer(CHM).By using the single mode diode laser to get higher polarization efficiency,the stronger magnetic-resonance signal compared with the conventional lamp-pumped scheme is got.By measuring the noises from light,background field,pulse discharge and signal amplifier circuits,we find that the light power fluctuation is the dominant noise.We study the relation between signal-to-noise ratio and the light intensity,and then find out an optimal light intensity.Under the best experimental parameters,the peak-to-peak noise can superior to 0.02 nT.The results of the experiment show that by improving the stability of the light power,the laser pumped CHM has great potential to achieve a higher accuracy than proton magnetometers,can be used as a new generation of main measuring equipment for constant weak magnetic field measurement. Related Articles | Metrics | Comments（0）

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Research on Measurement Method of Low Temperature Microdeformation of Parts Based on Industrial CT#br# DU De-yu, JIA Pei-zhi, LI Xiong-wei, Liu Lin, ZHAO Bin, WANG Xiao-ning, SONG Jin-cheng Journal of Astronautic Metrology and Measurement    2023, 43 (6): 71-75.   DOI: 10.12060/j.issn.1000-7202.2023.06.13 Abstract （77）      PDF（pc） （1884KB）（234）       Knowledge map    Save In order to solve the problem of directly measuring microdeformation of parts under low temperature conditions，a measurement method for low-temperature microdeformation of parts based on high-precision Industrial Computerized Tomography (ICT) was proposed.A testing platform for low-temperature microdeformation was established based on ICT,and the parts were scanned and analyzed under both low-temperature and normal-temperature conditions following a constructed table of voltage-current parameter combinations.The imaging principle of ICT was introduced initially,followed by an elucidation of key technologies involved in measuring microdeformation of parts under low-temperature conditions,and finally the experimental results were detailedly described and analyzed.The findings indicated that the proposed measurement method exhibited good repeatability and the problem of direct measurement of microdeformation in parts at low temperatures was effectively solved.For parts of which material linear expansion coefficients have not been precisely measured,ICT can be used to measure microdeformation,serving as an alternative to estimating microdeformation using referenced linear expansion coefficients. Related Articles | Metrics | Comments（0）

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Measurement Uncertainty Analysis of Spectral Irradiance of Self-calibration Spectral Irradiance Meter LI Jian-jun, HU You-bo, DING Lei, ZHAI Wen-chao, XIA Mao-peng, ZHENG Xiao-bing Journal of Astronautic Metrology and Measurement    2023, 43 (3): 40-46.   DOI: 10.12060/j.issn.1000-7202.2023.03.08 Abstract （59）      PDF（pc） （1188KB）（230）       Knowledge map    Save Based on the principle of spontaneous parametric down conversion,a wide band correlated photon source is generated.Combined with traditional spectral irradiance measurement instruments,a new spectral irradiance measurement method based on correlated photons self-calibration is proposed.The spectral irradiance measurement principle and experimental system were introduced,and a study on the transfer chain of “channel quantum efficiency→spectral photon number rate→spectral power responsivity→spectral irradiance” was carried out.A radiation measurement model based on correlated photons self-calibration was established,and the uncertainty of spectral irradiance measurement was analyzed detailedly.Using a 488 nm laser beam passing through a collimated light source of an integrating sphere and collimator as the irradiance source,a comparative experiment between a correlated photon self-calibration spectral irradiance meter and a standard irradiance meter was conducted,and the preliminary verification showed that the consistency of the two measurement methods was better than 4.2 %. Related Articles | Metrics | Comments（0）

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Theoretical Background of Quantum Metrology DING Guo, GUO Sheng, ZHU Jing-hua, DENG Peng-bo Journal of Astronautic Metrology and Measurement    2023, 43 (6): 44-48.   DOI: 10.12060/j.issn.1000-7202.2023.06.08 Abstract （134）      PDF（pc） （736KB）（228）       Knowledge map    Save The history of quantum mechanics is outlined and the fundamental formulas:the Schrdinger equation with the interpretation of the wave function,the Pauli exclusion principle,and the Heisenberg uncertainty principle are presented.The latter is illustrated with sample numerical calculations using this principle.The application of quantum effects in metrology,and present and compare the limits of accuracy and resolution of classical and quantum standards are briey discussed.The role of quantum effects in the new International System of Units are discussed as well.Although quantum effects have a wide range of applications,it is difficult to be understood by the public as it is strongly theoretical,which is reflected in many shortcomings in the 2018 version of SI.Finally,development of quantum metrology are prospected. Related Articles | Metrics | Comments（0）

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Research on Two-stage SQUID Amplifier for Signal Readout of Metallic Magnetic Calorimeter LI Tai-yu, ZHENG Yi-ning, XU Yuan-xing, CHEN Ying-yu, TANG Li-hong, ZHAO Yue, WANG Chao-qun, XIE Hang-xing, GAO Bo, WANG Zhen Journal of Astronautic Metrology and Measurement    2023, 43 (3): 16-20.   DOI: 10.12060/j.issn.1000-7202.2023.03.04 Abstract （49）      PDF（pc） （1176KB）（227）       Knowledge map    Save Metallic Magnetic Calorimeter (MMC) is a low-temperature photon detector with high energy resolution.The heat generated by photon absorption induces a rapid change of the magnetization of a metallic paramagnetic film.Precise measurements of the magnetization signal provides an accurate way to deduce the photon energy.the readout of MMC relies on low noise current amplifiers based on Superconducting Quantum Interference Devices (SQUID).The research report a two-stage SQUID amplifier circuit for MMC.The first stage SQUID adopts a 2nd order gradiometer design,which makes the amplifier less sensitive to the environmental noise.At liquid helium temperature,the circuit working in the flux-locked-loop mode achieved a transimpedance gain of 27 400 V/A,and a white noise floor of 11.5 pA/Hz1/2. Related Articles | Metrics | Comments（0）

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Development Status of Weak Current Metrology Calibration Technique Based on Atomic Magnetic Field Detection LI Wei-peng, WEI Xiao-gang, YANG Ren-fu Journal of Astronautic Metrology and Measurement    2023, 43 (5): 36-40.   DOI: 10.12060/j.issn.1000-7202.2023.05.05 Abstract （86）      PDF（pc） （984KB）（227）       Knowledge map    Save With the rapid improvement in the sensitivity of atomic magnetometers,the application of magnetic field measurement methods based on atomic ensemble is gradually expanding.In recent years,several studies have been conducted on the use of atomic magnetometers for weak current measurements,and the results have revealed the potential of this measurement method for enhancing current stability.With the high sensitivity characteristics of an atomic magnetometer,weak changes in the current are monitored by the magnetic field generated by the current,and the current is stabilized using feedback from the magnetic field measurements.It mainly describes the basic principle of atomic magnetic field detection and the current status of its application in the field of current measurement,and analyzes the key influencing factors of current measurement using atomic magnetometers,and looks forward to the development trend of this technology. Related Articles | Metrics | Comments（0）

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Research on Measurement Method of Milli Tesla Class Magnetic Field Based on Coherent Population Trapping ZHANG Fan, WANG Dongping, YI Siyue, CHENG Zhiyong, XIE Yin, PEI Huagang Journal of Astronautic Metrology and Measurement    2024, 44 (2): 98-102.   DOI: 10.12060/j.issn.1000-7202.2024.02.17 Abstract （107）      PDF（pc） （1193KB）（219）       Knowledge map    Save A method to measure milli tesla class magnetic field by coherent population trapping effect is proposed.Using linearly polarized laser to interact with 87Rb atoms,two divided CPT resonance signals caused by the nucleus spins in the magnetic field is obtained,and the magnetic induction strength of the magnetic field is derived by analyzing the splitting distance between the two CPT resonance signals.This method can eliminate nonlinear error caused by the high-order term to improve the accuracy of measuring the milli tesla class magnetic field and provides a new scheme for the quantum standard of milli tesla magnetic field. Related Articles | Metrics | Comments（0）

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Development and Uncertainty Analysis of Heat Flow Field Calibration Device ZHANG Jun-qi, LI Chen-yuan, LIU Bao-ju, ZHOU Ming-rui, WU Wei-wei, ZHAO Hua-ye, LIU Xin Journal of Astronautic Metrology and Measurement    2023, 43 (4): 8-12.   DOI: 10.12060/j.issn.1000-7202.2023.04.02 Abstract （86）      PDF（pc） （1988KB）（217）       Knowledge map    Save To meet the demand of field calibration of radiant heat flow measurement system,a heat flow field calibration device was developed based on high power semiconductor laser heat source generation technology.The composition of the heat flow calibration device and the design parameters of each component of the device is introduced.The optical analysis software is used to design the optical path of heat flow source.By analyzing each uncertainty component of the field calibration device and calculating the combined extended uncertainty,the extended uncertainty of 2.7% is realized by the device,which can meet the requirements of heat flow field calibration. Related Articles | Metrics | Comments（0）

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Research on Power Data Analysis based on Deep Learning LIU Wei, ZHANG Bo, LIANG Ming-yuan Journal of Astronautic Metrology and Measurement    2023, 43 (3): 97-102.   DOI: 10.12060/j.issn.1000-7202.2023.03.18 Abstract （58）      PDF（pc） （899KB）（216）       Knowledge map    Save Aiming at the problems of poor classification accuracy of electrical appliances caused by the limited scope of application and complex model of traditional power data analysis methods,a power data analysis model based on multi-layer stacked Long Short-Term Memory (LSTM) network is proposed.Firstly,the features of power data are extracted from the spectrum diagram,Mel Frequency Cepstrum Coefficient (MFCC) and Mel spectrum diagram of power data,and then applied to the deep learning model to improve the performance of classification tasks,so as to improve the over fitting problem.Secondly,a multi-layer stacked LSTM model is established to effectively improve the classification and regression ability of the model.Finally,an improved soft coding and multi-scale training method is proposed to prevent the peak probability distribution and improve the generalization ability of the model.In the experimental stage,the proposed model is verified by taking the household power data set as an example.The simulation results show that the soft coding and multi-scale training of the proposed model have a certain effect on accelerating the training effect,and the final classification accuracy reaches 89.85 %. Related Articles | Metrics | Comments（0）