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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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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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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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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 Research Advancements and Trends in Chip-integrated Metrology within the Framework of the New International System of Units (SI) GUO Linbao, ZHAO Zhao, LI Daozheng, LI Yajie, SHA Changtao, ZHANG Hong Journal of Astronautic Metrology and Measurement    2024, 44 (5): 8-15.   DOI: 10.12060/j.issn.1000-7202.2024.05.02 Abstract （94）      PDF（pc） （2782KB）（186）       Knowledge map    Save Chip-integrated metrology serves as an implementation method,possessing the advantages of high efficiency and low cost.The significant revolution of the International System of Units (SI) has freed metrological work from the trouble of physical benchmark and made the methods of reproducing values more flexible.Along with the development of quantum measurement methods,a number of chip-scale metrological standard device have been born.Micro-Electro-Mechanical System (MEMS),microfluidics,and chip-integrated laser are key supporting technologies for chip-integrated metrology.Based on quantum measurement technology,the realization of some fundamental units in the SI,like time,length,temperature,and current,has already taken the shape of chipization.Overall,chip-integrated metrology is still in its infancy,mainly in the form of chip-based sensing elements.In the future,continuous efforts should be made to develop chip-integrated metrological standards instruments and gradually construct a chip-integrated traceability chain to fulfill chip-integrated metrology. Related Articles | Metrics | Comments（0）

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Review of Optical Gyroscope Goniometry Technology LIN Yuezhong, JIA Peizhi, LIU Hua, ZHAO Bin, SONG Jincheng Journal of Astronautic Metrology and Measurement    2024, 44 (6): 69-74.   DOI: 10.12060/j.issn.1000-7202.2024.06.08 Abstract （59）      PDF（pc） （3748KB）（178）       Knowledge map    Save Angle is the basic parameter of geometric measurement,and the results of angle measurement affect the accuracy of measurement,detection and calibration.With the progress of precision machining and manufacturing technology,optical gyroscopes are widely used in the measurement and calibration of dynamic angles,and play an important role in inertial measurement with the advantages of high precision,good reliability and fast response speed.The basic working principle of optical gyroscope is introduced,the research status of optical gyroscope angle measurement technology at home and abroad is expounded,and the application of ring laser dynamic goniometer and angular velocity standard device in angle measurement is introduced.Nowadays,optical gyrometer goniometry is developing rapidly in the direction of digitalization,automation and intelligence,and future research will further improve the sensitivity,stability and dynamic performance of angle measurement. Related Articles | Metrics | Comments（0）

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Research on Pressure Sensors Temperature-response Characteristics Calibration Device GAO Bingtao, SUN Haitao, HUO Ruidong, GUO Yimeng, WANG Xiaosan, HUANG Qigang Journal of Astronautic Metrology and Measurement    2024, 44 (4): 17-22.   DOI: 10.12060/j.issn.1000-7202.2024.04.03 Abstract （61）      PDF（pc） （2955KB）（143）       Knowledge map    Save In order to ensure the accuracy of the measurement data,it is necessary to calibrate the temperature-response characteristics parameters of the pressure sensor under high and low temperature environment.The temperature-response characteristics calibration device for the pressure sensors is developed by designing systems such as the standard pressure sources,the temperature isolation units,and the multi-point temperature measurement calibration chambers.The calibration of the pressure sensors，within the pressure range of absolute pressure 2~500 kPa and under the ambient temperature conditions of -50 ℃~100 ℃，is realized.The measurement uncertainty of the calibration device is better than 0.05% (k=2),laying the foundation for conducting research on the temperature response characteristics of pressure sensors. Related Articles | Metrics | Comments（0）

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Research on Straightness Measurement of Guide Rails Based on Laser PSD JIN Lu, QIAN Chen, WU Bo, SHI Zhengbo, SUN Xuning, XU Yunliang, WANG Wei Journal of Astronautic Metrology and Measurement    2024, 44 (4): 57-63.   DOI: 10.12060/j.issn.1000-7202.2024.04.10 Abstract （47）      PDF（pc） （2084KB）（139）       Knowledge map    Save Aiming at the measurement efficiency issue caused by the limitations of rail structure characteristics,rail length,assembly position,and other conditions in straightness measurement during the assembly of aerospace model rails,a laser PSD（Position Sensitive Detector）based on rail straightness measurement method was studied.An automated measurement system consisting of PSD receiver,distance module,signal processing unit,and motion unit was designed,and the measurement accuracy of the system was verified,using a laser tracker standard.The measurement accuracy is better than ±0.1 mm,and the measurement efficiency is increased by 5 times.After software and hardware compatibility modification,it can also be used for measuring the spatial straightness,width,and other dimensions of various large guide rails. Related Articles | Metrics | Comments（0）

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Remote Sensing Image Classification Based on Deep Convolution Transfer Learning Network Algorithm WANG Xiaozhuo, WANG Kai, CAO Shu Journal of Astronautic Metrology and Measurement    2024, 44 (4): 97-102.   DOI: 10.12060/j.issn.1000-7202.2024.04.17 Abstract （122）      PDF（pc） （787KB）（131）       Knowledge map    Save Due to the lack of resampling processing for graphic features,the final classification accuracy and the classification performance are not ideal.To this end,a remote sensing image classification based on deep convolution transfer learning network algorithm is proposed.By dividing the geometric region of the original remote sensing image,extracting the descriptors for the distorted geometric pixel,combining the scale space and pixel registration and the rotation angle of the image is calculated,and the geometric correction of the remote sensing image is completed.The dual stream network architecture is innovatively adopted to splice the channel of pixel frequency bands,combining the interaction results of image consistency joint features,outputting image fusion features,and resampling the features with new pixel value index.The deep convolutional transfer learning network algorithm is used to calculate the probability of the input image in the reference class,so as to realize the remote sensing image classification.The application results of the example show that the designed method has high classification accuracy and better classification performance in remote sensing image classification. Related Articles | Metrics | Comments（0）

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Intelligent Target Calibration Device for Armed Helicopter Based on ABE System BAO Shanying Journal of Astronautic Metrology and Measurement    2024, 44 (4): 82-86.   DOI: 10.12060/j.issn.1000-7202.2024.04.14 Abstract （55）      PDF（pc） （1495KB）（122）       Knowledge map    Save Referring to HB 6750-93 General Requirements for Calibration and Calibration of Airborne Weapon Fire Control Systems,aiming at the existing issues of calibration process models,such as low applicability,large area occupation,heavy equipment,low efficiency,complex operation and low accuracy,an intelligent on-site calibration system is constructed based on ABE system and intelligent theory,and research on key technologies which including benchmark axis measurement,target screen simulation and weapon axis pointing guidance is carried out,and an intelligent target calibration device for armed helicopters is developed，which can realize lightweight,intelligent,and precise targeting in free scene. Related Articles | Metrics | Comments（0）

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Design and Implementation of Agile Vector Signal Generator TIAN Yunfeng, HU Bin, WANG Zhiqiao, WANG Xinyang, HE Wei, JIA Lin Journal of Astronautic Metrology and Measurement    2024, 44 (5): 61-67.   DOI: 10.12060/j.issn.1000-7202.2024.05.10 Abstract （46）      PDF（pc） （3488KB）（120）       Knowledge map    Save In order to meet the needs of wide band agile vector signals for the test of radar systems,communication equipment and the construction of complex electromagnetic environment，using many kinds of ways simultaneously to generate the signal,such as Direct Analog Synthesis(DAS),Phase-Locked Loop(PLL)synthesis,Direct Digital Synthesis(DDS),I/Q digital vector modulate etc.，agile vector signal generate technology is researched.Many key technologies,such as frequency agility,amplitude agility,modulation agility,high speed time synchronization and control,complex electromagnetic signals generation etc.，are broken through.The agile vector signal generator is combinated with the advantages of vector signal generator,agile signal generator and low phase noise signal generator.The advanced technical indicators,such as 40 GHz frequency range,100 ns agile time,1 GHz instantaneous bandwidth etc.，are realized. Related Articles | Metrics | Comments（0）

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Supporting Data Progressing Scheme for Spacecraft Electrical Performance Testing with Multiple Interfaces YUAN Jinqian, SHANG Shunan, LI Kunze, ZHANG Haocong, GAO Jiahui, LU Juan Journal of Astronautic Metrology and Measurement    2024, 44 (4): 76-81.   DOI: 10.12060/j.issn.1000-7202.2024.04.13 Abstract （63）      PDF（pc） （982KB）（116）       Knowledge map    Save In addressing the practical problems currently faced by spacecraft testing a multiple types of data access method is introduced,which is designed to tackle issues such as improving telemetry real-time decoding performance,accessing satellite payload data,processing telemetry for both the primary and secondary satellites,and handling high-speed telemetry processing.The design concept,implementation methods,and application scenarios of the scheme is provided.Through practical applications,it’s verified that through the method，the testing time was effectively reduced,the data interface and the maximum decoding efficiency were expended，and the automation level of satellite testing was enhanced.Scalability,low-coupling,and high-efficiency data processing,which gives the method significant advantages. Related Articles | Metrics | Comments（0）

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In-Place Calibration for Coupling Error of Six-axis Dynamometer Based on Fiber Bragg Grating CHEN Fayin, XI Yonghui Journal of Astronautic Metrology and Measurement    2024, 44 (4): 11-16.   DOI: 10.12060/j.issn.1000-7202.2024.04.02 Abstract （65）      PDF（pc） （1784KB）（110）       Knowledge map    Save Different from strain gauge dynamometers,six-axis dynamometer based on fiber Bragg grating (FBG) adopts the structural force measurement principle,and one of its main performance parameters is the coupling error.Due to the limitation of its application scenario,in-place calibration is usually performed.The sensing structure and principle of the FBG six-axis dynamometer are analyzed,and an in-place calibration device without a standard force source is proposed according to the coupling error model.An in-place calibration method based on a robot arm for coupling error is also established,in which the calibration process is simplified and the source of uncertainty is reduced.The uncertainty of calibration results is analyzed with a practical example,and the effectiveness of the method is verified. Related Articles | Metrics | Comments（0）

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Research on Measurement Method for Spectral Emissivity and Hemispherical Emissivity of Infrared Materials WANG Ruiqin, HAN Ying, GAO Yuan Journal of Astronautic Metrology and Measurement    2024, 44 (4): 40-43.   DOI: 10.12060/j.issn.1000-7202.2024.04.07 Abstract （121）      PDF（pc） （1933KB）（108）       Knowledge map    Save In response to the demand for accurate measurement of surface emissivity of infrared materials,the directional spectral emissivity and hemispherical total emissivity of the sample materials were measured using a spectral equipment with integrating sphere attachment and a emissometer at room temperature in the laboratory,and the results were converted.Through the study of the two measurement methods,it is shown that the spectral emissivity of infrared materials is consistent with the hemispherical total emissivity,which verifies the effectiveness of the two measurement methods and provides a reference for the measurement of surface emissivity parameters of infrared materials. Related Articles | Metrics | Comments（0）

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Method Research in Stitching Linear-scan for Roundness Error of Small Cylinders DING Guo, GUO Sheng, ZHU Jinghua, LI Peng, WANG Qian Journal of Astronautic Metrology and Measurement    2024, 44 (4): 44-50.   DOI: 10.12060/j.issn.1000-7202.2024.04.08 Abstract （52）      PDF（pc） （3503KB）（108）       Knowledge map    Save A new method for roundness measurement of small cylinders is presented instead of the conventional rotary-scan method. By the new method,which is referred to as the stitching linear-scan method,roundness measurement of a small/micro cylinder by stitching a series of arc profiles is realized,adopting stitching in both the radial and the circumference directions at different angular positions linearly scanned by a surface form profiler,without alignment of the cylinder and a rotational datum. Description of the principle is proposed in the new method,by which a roundness measuring machine is constructed. Experiments and uncertainty analysis are presented to demonstrate the effectiveness of the method,and the results between traditional roundness measuring machine and new machine are compared as well. Related Articles | Metrics | Comments（0）

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Accurate Measurement of Transfer Impedance and MCM Uncertainty Assessment of Communication Cables DING Xiang, ZHU Menghan, DENG Xiaoqian Journal of Astronautic Metrology and Measurement    2024, 44 (5): 32-38.   DOI: 10.12060/j.issn.1000-7202.2024.05.05 Abstract （75）      PDF（pc） （1442KB）（108）       Knowledge map    Save To solve the problem that the outer cylinder distribution parameters,joint connection parameters and other tests seriously affect the accuracy of value traceability in the process of testing communication cable transfer impedance using the tri-coaxial method in the field of high-precision measurement and calibration.By separately measuring the S parameters of the fixture calibrator and the cable under test,using the network cascade algorithm to calculate the shielding attenuation,and finally calculating the transfer impedance,the error can be effectively eliminated,aiming to improve the accuracy of the transfer impedance measurement.Starting from the measurement principle of the tri-coaxial method,the standard test plan is analyzed,the two-port S matrix and A matrix conversion and network cascade algorithm are discussed in detail,and an accurate measurement plan for transfer impedance is derived.It was verified through experiments and the Monte Carlo Method (MCM) was used to evaluate the measurement uncertainty,and the evaluation result was Ur=8%（k=2）. Related Articles | Metrics | Comments（0）

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Application of Continuous Thermocouple Temperature Measuring System in High Temperature Aging System SUN Qiang, HUANG Xianwu, JIN Ran, LI Yinchuan, FU Jie Journal of Astronautic Metrology and Measurement    2024, 44 (5): 92-96.   DOI: 10.12060/j.issn.1000-7202.2024.05.15 Abstract （94）      PDF（pc） （3486KB）（108）       Knowledge map    Save In order to realize the real-time monitoring of the temperature in the effective working area of the high temperature aging system,and avoid the failure and damage of the chip or electronic component caused by abnormal temperature,according to the principle that the output thermoelectric potential of the continuous thermocouple is always corresponding to the highest temperature in the temperature sensing section,a set of real-time temperature measurement system using the continuous thermocouple as the temperature sensing element is built.The system is simple in layout and low in cost.The real-time temperature measurement system is used to verify the test data of the constant state and the temperature gradient state respectively,and the expected effect can be achieved.The system can effectively monitor the aging system working area temperature,achieve centralized monitoring,and according to the chip or electronic components aging temperature,be free to set early warning and alarm temperature points. Related Articles | Metrics | Comments（0）

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Research on Continuous Frequency Quantum Electric Field Measurement JIN Gang, CHENG Yongjie, PENG Bo, HAN Binbin, HUANG Chengzu, ZHAO Peng, LIU Xingxun, QI Wanquan Journal of Astronautic Metrology and Measurement    2024, 44 (3): 36-40.   DOI: 10.12060/j.issn.1000-7202.2024.03.06 Abstract （36）      PDF（pc） （1694KB）（107）       Knowledge map    Save To solve the problem of the limited bandwidth,when measuring the RF electric field using Rydberg atom EIT-AT method,a method of continuous broadband RF field measurement is proposed.The experiment of quantum Rydberg RF electric field measurement is carried out in TEM cell.The fiber-coupled quantum probe is placed in TEM cell,based on the a model of non-resonance interaction between RF field and Rydberg atoms,According to the shifted spectrum frequency of Rydberg in electric field,the electric field can be calculated.The method can be used to the measurement of electric field for the continuous frequency between 50 MHz and 500 MHz,which enlarge the range of application of quantum field measurement,the propose can also be applied in other band electric field measurement,such as frequency above 1 GHz,the fiber coupled atom-based electric probe can also be used for electric field environment detection in narrow and small space,such as pipes and mini case. Related Articles | Metrics | Comments（0）

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Second-order Doppler Frequency Shifts of Ions in Paul Traps MIAO Shengnan, ZHENG Ying, ZHANG Shengkang, CHEN Haijun, ZHANG Jianwei, WANG Lijun Journal of Astronautic Metrology and Measurement    2024, 44 (5): 68-75.   DOI: 10.12060/j.issn.1000-7202.2024.05.11 Abstract （66）      PDF（pc） （2463KB）（106）       Knowledge map    Save The evaluation of the second-order Doppler frequency shift (SODFS) of trapped ions in Paul traps has been studied in this paper.The motion of confined ions in a Paul trap consists of three components:secular motion,micromotion,and excess micromotion.This paper focused on the ion excess micromotion,which is rarely discussed when evaluating the SODFS of ions.Based on the hypothesis that the ion density is uniformly distributed in the radial direction,a model was proposed to evaluate the total SODFS for an ion ensemble with temperature less than 100 mK in this paper,which consists of three contributions of ion motion.The effectiveness of the model has been verified by molecular dynamics simulations and experiments.The model in this paper offers advantages in accurately evaluating the SODFS for the ion trap,which is appliable for optical clocks based on ions and microwave clocks based on ions,especially those of laser-cooled ion microwave clocks based on large ion clouds. Related Articles | Metrics | Comments（0）

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Evaluation Method and Verification of Uncertainty in THz Antenna Pattern Measurement Based on Planar Near Field HUANG Chengzu, LIU Xingxun, LIU Ting, XU Xingming Journal of Astronautic Metrology and Measurement    2024, 44 (5): 25-31.   DOI: 10.12060/j.issn.1000-7202.2024.05.04 Abstract （49）      PDF（pc） （2786KB）（104）       Knowledge map    Save Facing with the demand for Tera Hertz(THz) antenna pattern calibration,analyzes and evaluates the measurement uncertainty of planar near field measurement based on the measurement device of THz antenna pattern and the classic planar near field measurement uncertainty analysis model of NIST.And the measurement uncertainty is verified through comparative method.The experimental results indicate that the evaluation method is feasible in the set frequency band and is expected to remain applicable in higher bands.This paper introduces a THz antenna pattern measurement device based on planar near field first,then analyzes the sources of measurement uncertainty one by one,compares and verifies results through far field measurement.And then looks forwards to the future work. Related Articles | Metrics | Comments（0）

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Test and Analysis of Thermal Response Time of Temperature Sensor LIU Baoju, GUO Yafei, ZHANG Junqi, ZHANG Zhongjie, LV Yueyuan, LIU Lin, CHEN Yiqing Journal of Astronautic Metrology and Measurement    2024, 44 (4): 35-39.   DOI: 10.12060/j.issn.1000-7202.2024.04.06 Abstract （150）      PDF（pc） （2601KB）（100）       Knowledge map    Save Most of the domestic thermal response time tests for temperature sensors are conducted in 90 ℃ silicone oil by oil bath method,and the test method is single without considering the relationship between the actual use environment of temperature sensors and the test environment,and the test method is manual test with low efficiency and poor reproducibility.To solve this problem,an automatic test device for thermal response time of temperature sensor is designed based on Labview software.The thermal response time of PT100 platinum resistor,PT1000 platinum resistor and thermistor temperature sensor is tested,and the influence of different packaging and heating methods on the thermal response time of temperature sensor is analyzed.It is proved that different packaging methods and heating methods have great influence on the thermal response time test.The test device studied can be applied to the response time measurement of all types of temperature sensors. Related Articles | Metrics | Comments（0）

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Testing Method for Angular Velocity Sensitivity of Pendulous Accelerometer#br# GUAN Wei, WANG Kuan, LIN Zhenming Journal of Astronautic Metrology and Measurement    2024, 44 (6): 83-86.   DOI: 10.12060/j.issn.1000-7202.2024.06.10 Abstract （35）      PDF（pc） （707KB）（100）       Knowledge map    Save Angular velocity sensitivity is an important item for evaluating the accelerometer error caused by angular motion.Current testing standards of accelerometer are lack of specific testing procedures and makes it hard to compensate the angular motion error.At first,testing principles are proposed based on definitions of angular velocity sensitivity in standards home and abroad.Then,by reference to rotating calibration method of accelerometer,co-axis dual-turntable centrifuge is introduced to measure angular velocity sensitivity.At last,a specific testing procedure of angular velocity sensitivity is described by taking single-axis accelerometer as an example. Related Articles | Metrics | Comments（0）

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Research on Test System of Dew Point Sensor Response Time LI Chenyuan, ZHAO Huaye, WANG Yong, YU Zhen, LIU Baoju, ZHANG Junqi, LIU Lin, CHEN Yiqing Journal of Astronautic Metrology and Measurement    2024, 44 (4): 51-56.   DOI: 10.12060/j.issn.1000-7202.2024.04.09 Abstract （65）      PDF（pc） （1127KB）（95）       Knowledge map    Save The role and significance of the current dew-point sensor response time characteristic measurement in the field of system testing of large equipment in China is discussed,the current research status of calibration of gas dew point temperature response time measurement in China is introduced,and a gas dew point temperature response time measurement system is designed.The system has the advantages of high measurement accuracy,wide range of step control and convenient operation,which provides technical support for solving the difficult problem of high precision measurement of gas dew point temperature response time.The device is used to test the response time characteristics of quartz resonant dew point sensor and alumina dew point sensor respectively.The research results provide guidance for the future research and improvement of the response time characteristics of humidity sensor elements. Related Articles | Metrics | Comments（0）

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Research on Calibration Method of Screen-type Side Projection Optical Target Simulation System SU Xiaoting, LI Qi, CHEN Zhao, ZHU Feiyue, WANG Chaofeng, YANG Yang Journal of Astronautic Metrology and Measurement    2024, 44 (4): 23-29.   DOI: 10.12060/j.issn.1000-7202.2024.04.04 Abstract （51）      PDF（pc） （2354KB）（93）       Knowledge map    Save Aiming at the calibration problem of the side projected simulator without entity datum,a method with base lines from a laser level meter is proposed,and the main factors affecting the accuracy of the line of sight (LOS) angle are analyzed.For the two main error sources of laser baseline error correction and screen flatness,an analysis model of the LOS angle is established.The absolute error of calibrated LOS angle is from 0.008 5 to 0.042 4 degrees (azimuth) and 0.003 to 0.120 degrees (pitch),which can meet the demand of HWIL(Hard Ware-In-Loop） simulation. Related Articles | Metrics | Comments（0）

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The Torque Calibration Technology Research of Micro Electromagnetic Components QI Hongli, MA Xianglong, LI Tao Journal of Astronautic Metrology and Measurement    2024, 44 (5): 55-60.   DOI: 10.12060/j.issn.1000-7202.2024.05.09 Abstract （48）      PDF（pc） （2311KB）（93）       Knowledge map    Save Torque is one of the most important parameters of the micromagnetic devices of inertial navigation system,which is usually from the milli-Nm to 10-6 Nm.In order to measure 10-6 Nm torque value of micromagnetic devices,this paper researches a standard torque device,which has a torque calibration and measurement range reaching to 10-6 Nm.The device adopts the new torque calibration and measurement technology based on the flexure suspension and zero-stiffness theory,designs the ultra-thin,one-piece flexure suspension protection structure,realizes the zero-stiffness suspension structure of the device,and solves the multi-degrees-of-freedom torsional deformation problem of the flexure suspension,so make the micro-torque measurement range expand to 10-6Nm consequently.Simultaneously,this paper realizes the small torque automatic loading technology,puts forward the idea of automatic loading of milligram (mg) level weights step by step,solves the automatic loading problem of heterogeneous weights,eliminates the impact influence generated by manual loading of traditional small-torque devices,realizes the device's full-range automatic calibration and measurement,and enhances the quantity transmission reliability.Experiments shown that the device has a measurement range from 10-6 Nm to 10-4 Nm,and a relative measurement uncertainty better than 1% (k=2). Related Articles | Metrics | Comments（0）

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Development of Time Code Equipment Based on Common View Technology CAI Yongmei, BAO Jihua, ZHANG Yongmin, YANG Zhangjun, LI Dazhen, ZHANG Ran, WANG Xin Journal of Astronautic Metrology and Measurement    2024, 44 (3): 61-67.   DOI: 10.12060/j.issn.1000-7202.2024.03.10 Abstract （50）      PDF（pc） （924KB）（91）       Knowledge map    Save Time codes have wide applications in various fields such as aerospace, finance, and power. Based on satellite common view technology, the time difference between the central station and the remote station is obtained. By taming the rubidium clock, a long-distance and high-precision time code synchronization method between the central station and the remote station is studied, which enables high-precision timing at the remote station and high-precision time code calibration for general time system equipment. Through experimental verification, the time synchronization standard deviation between the remote station and the central station is better than 5 ns, the accuracy of 1PPS for external timing by the remote station is better than ± 20 ns, the accuracy of B (DC) is better than ± 20 ns, and the accuracy of B (AC) is better than ± 10 μs; Remote station external time code measurement deviation is 1PPS, B (DC) ≤ 20 ns, B (AC) ≤ 10 μs. Based on commonview taming, time code synchronization enables remote stations to have high-precision inspection and support capabilities that cover different support requirements, providing a high-precision and convenient means of time-frequency equipment inspection, testing, and emergency support. Related Articles | Metrics | Comments（0）

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Experimental Study on Pumping Methods of Micro CPT Atomic Clock BAI Daibing, LIN Zaisheng, WU Chenfei, LV Yutao, LIU Meng, GONG Hang, MA Ming, XV Jie, XUE Xiaobo, ZHANG Shengkang Journal of Astronautic Metrology and Measurement    2024, 44 (3): 11-16.   DOI: 10.12060/j.issn.1000-7202.2024.03.02 Abstract （64）      PDF（pc） （1562KB）（90）       Knowledge map    Save The （Coherent Population Trapping）CPT atomic clock is a compact atomic frequency standard based on the principle of coherent population trapping, which does not require a microwave resonant cavity, which is beneficial for reducing the volume and power consumption of physical systems. In order to explore polarization pumping methods suitable for micro CPT atomic clocks, three pumping methods were selected, including single circularly polarized light, parallel linearly polarized light, and elliptical polarized light, under the limitations of physical system volume, power consumption, and complexity. Based on the 6mm × 6mm × 6mm micro 87Rb cell, desktop systems were constructed to measure the linewidth and SNR of CPT resonance signals using three methods. The results show that micro CPT atomic clocks are more suitable for using elliptically polarized light method. Related Articles | Metrics | Comments（0）

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Causes Analysis of Abnormal Action of Lifting Working Device FAN Yi, CHEN Zhao, SUN Yu, HE Huan Journal of Astronautic Metrology and Measurement    2024, 44 (4): 92-96.   DOI: 10.12060/j.issn.1000-7202.2024.04.16 Abstract （61）      PDF（pc） （1422KB）（90）       Knowledge map    Save In the space with complex equipment layout,the density of various electro-mechanical products and electronic devices continues to increase,and the coupling effect of various factors such as circuit,magnetic field and mechanical motion should be considered in product design,especially the matching of characteristics between devices should be confirmed.Taking the abnormal action of a lifting device as an example,the mechanism of common frequency interference when the proximity sensor and the stepper motor work together is explained,and the importance of device characteristic matching in the design of electro-mechanical products is expounded. Related Articles | Metrics | Comments（0）

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Research on Quantum Coherence Based Polarization Characteristics of Laser Metrology for Co Directional Transmission in Rubidium Atomic Gas JIA Yunfeng, LIU Weiping, LI Dong, YU Bing, ZHANG Yunlong, YOU Yue, WANG Nanxi, CHEN Jiejing, LIU Yize Journal of Astronautic Metrology and Measurement    2024, 44 (5): 74-80.   DOI: 10.12060/j.issn.1000-7202.2024.05.12 Abstract （48）      PDF（pc） （2377KB）（90）       Knowledge map    Save To address the issue of polarization metrology during the transmission of laser in the gas medium,a solution is proposed that utilizes the quantum coherence effect of two laser beams propagating in the same direction within the rubidium atomic gas medium.Through the Stokes polarization inversion method to detect the intensity distribution of one of the laser beams,the polarization distribution of the other laser beam can thus be obtained.The specific implementation involves simultaneously passing the two laser beams through the rubidium atomic gas.By altering the polarization direction and ellipticity of one of the laser beams,the intensity and polarization variations of the other detection laser beam after passing through the rubidium atomic gas are investigated.The experimental results were verified by replacing a laser beam with mixed vector light and angular vector light.It is discovered that when the polarization azimuth and ellipticities of the two laser beams are the same,the intensity of the laser reaches its maximum,yet the polarization distribution remains unchanged.For this,a mathematical model of quantum coherence is proposed for explanation,and ultimately,the feasibility of the proposed quantum coherence mathematical model is verified through experiments on the detection of the coherent time of transition energy levels. Related Articles | Metrics | Comments（0）

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Research on Beam Width Calibration Method of Microwave Landing Simulator XU Tao, GAO Ran Journal of Astronautic Metrology and Measurement    2024, 44 (4): 30-34.   DOI: 10.12060/j.issn.1000-7202.2024.04.05 Abstract （61）      PDF（pc） （998KB）（84）       Knowledge map    Save The beam width is an important parameter of the MLS (Microwave Landing Simulator),and it is essential to regularly calibrate this parameter.The calibration method for this parameter output by the MLS is studied,focusing on the extraction and calculation of the signal.Firstly,the microwave signal output by the MLS is collected and processed to obtain the raw data related to the relative position and angle between the simulated aircraft and the landing equipment.The raw data is then processed and calculated.Secondly,for the beam width parameter,the extraction of the pulse 3 dB points of the forward scan beam and the return scan beam is implemented.Finally,the proposed method is verified through practical applications to assess its effectiveness and reliability in the MLS.The uncertainty analysis of the calibration of the beam width is carried out.The results provide new methods and technical support for the calibration of the beam width parameter in the MLS. Related Articles | Metrics | Comments（0）

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The Study on the Measurement of the Ambient Dose Equivalent of Gamma Radiation in n,γ Mixed Radiation Fields Using a G-M Counter WANG Yuchen, XU Xinyu, LI Chunjuan, LIU Yina, WANG Zhiqiang, DUAN Junyi, LUO Hailong Journal of Astronautic Metrology and Measurement    2024, 44 (5): 86-91.   DOI: 10.12060/j.issn.1000-7202.2024.05.14 Abstract （104）      PDF（pc） （1834KB）（82）       Knowledge map    Save Based on the mechanisms of neutron production and reactions,neutron reference radiation fields are n,γ mixed fields,where the gamma component primarily originates from gamma rays accompanying neutron production and those generated by the interaction of neutrons with materials in the radiation field environment.This paper investigates the application of an energy-compensated Geiger-Müller(G-M) counter in n,γ mixed radiation fields.Using the Monte Carlo (MC) particle transport code MCNP,the energy response of the G-M counter was simulated,and experimental validation was conducted in a gamma reference radiation field.The validation demonstrated that the energy compensation scheme effectively suppresses the over-response in the low-energy region.Utilizing this energy-compensated G-M counter,the ambient dose equivalent of gamma radiation in laboratory radioactive nuclide neutron source fields was measured.This improves the parameters of the reference radiation field and provides support for addressing calibration issues arising from the gamma response characteristics of neutron instruments. Related Articles | Metrics | Comments（0）

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Simulation Software Design of Inertial Navigation System Based on Naval Vessel Motion State ZHANG Xingfan, WEN Chaojiang Journal of Astronautic Metrology and Measurement    2024, 44 (4): 87-91.   DOI: 10.12060/j.issn.1000-7202.2024.04.15 Abstract （65）      PDF（pc） （3753KB）（79）       Knowledge map    Save The performance of naval vessel inertial navigation systems,particularly in terms of navigation errors,is intricately linked to vessel motion.To facilitate the examination of how vessel motion influences inertial navigation systems errors,a simulation software is developed,using vessel motion status as input to excite the inertial navigation systems.The simulation system’s structural composition,the architectural principles governing vessel motion status simulation,and the process of converting vessel motion status information into sensitive data for the inertial navigation systems are designed.Additionally,the functional composition and the practical application of the simulation software is elaborated in detail.It shows that,when provided with specific simulation parameters,the navigation parameters and associated errors can be output.Consequently,the developed simulation software holds value for investigating the dynamic performance errors of inertial navigation systems influenced by vessel motion status. Related Articles | Metrics | Comments（0）

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Study on Real-time Imaging Method for Multi-frequency Array Ground Penetrating Radar Data SUN Changjun, YU Wen, WANG Wei, SHI Xinghua Journal of Astronautic Metrology and Measurement    2024, 44 (3): 48-54.   DOI: 10.12060/j.issn.1000-7202.2024.03.08 Abstract （56）      PDF（pc） （2746KB）（77）       Knowledge map    Save Using multi-frequency array Ground Penetrating Radar (GPR) to detect defects in launch site pavements can obtain target information at different depths and resolutions. However, the vast amount of data generated by multi-frequency array GPR and the inability to merge data from different frequencies pose challenges for imaging and anomaly interpretation. To address this issue, a real-time imaging method for multi-frequency array GPR data is proposed, which utilizes ray projection in both depth and channel directions to more comprehensively display information on underground anomalies at different depths. The processing results of measured data indicate that this method effectively retains the basic information of underground anomalies, achieving rapid and high-precision display, thus meeting the application requirements for the rapid detection of defects in launch site pavements. Related Articles | Metrics | Comments（0）

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Research on Time and Frequency Application Based on RTKLIB Precision Point Positioning YU Xu, LIU Zhixiang, CUI Guowei, ZHANG Yan, JIANG Wenshuai, MA Chaoran, TAN Jie, ZHANG Ran Journal of Astronautic Metrology and Measurement    2024, 44 (3): 55-60.   DOI: 10.12060/j.issn.1000-7202.2024.03.09 Abstract （37）      PDF（pc） （3398KB）（75）       Knowledge map    Save The traceability comparison device has the function of remote time traceability which is based on satellite navigation system. The device that deployed in two places can trace back to the master laboratory to carry out the clock common view comparison, which helps the construction of the time-frequency traceability comparison system, which realizes high-precision time synchronization between two places. When the traceability comparison device receives satellites’ signals to calculate pseudo range, it is affected by ionospheric delay and other factors, which is not conductive to the positioning. To improve the capacity of traceability comparison and decrease the uncertainty of common view comparison, it is essential to explore the correlation between timing stability of single station and positioning accuracy. According to the calculation of the common view files of the Beijing Institute of Radio Metrology and Measurement (BIRMM) for three consecutive months, it can be obtained that the timing of a single station is stable in the range of 0.6~1.6 ns.Precision point positioning algorithm is used to calculate the navigation files and the precision ephemeris, and the positioning accuracy of East-North-Up directions can be obtained. The positioning accuracy is consistent with the fluctuation trend of the timing stability curve of single station. Linear regression analysis was used to explain 5.7% of the change in timing stability of single station, indicating a weak correlation between the two sites, which means improving the positioning accuracy of a single point has a positive impact on reducing the uncertainty of the common view. Related Articles | Metrics | Comments（0）

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Ultra-long Distance Ranging Technology on LiDAR WEI Longchao, WANG Pengyu Journal of Astronautic Metrology and Measurement    2024, 44 (3): 75-81.   DOI: 10.12060/j.issn.1000-7202.2024.03.12 Abstract （65）      PDF（pc） （2066KB）（73）       Knowledge map    Save For ultra-long distance ranging RVD Light Detection and Ranging(LiDAR) requirement，the integrated distance measurement and communication module have been developed. Without changing the original radar architecture and signal structure. The distance measurement and communication function has been realized for long-distance and high dynamic cooperative targets. The principle of distance measurement has been derived. Ranging errors caused by dynamic and clock performance factors has been analyzed. The formula for the influence of speed and clock performance on ranging error has been provided. It is concluded that in high dynamic environments, the combined effect of relative velocity, ranging period, and clock bias on both sides results in ranging system errors. A demonstration verification platform has been built to complete algorithm evaluation and principle demonstration. Related Articles | Metrics | Comments（0）

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A Method for Intelligently Setting Parameters of the PID Control System of Hydrogen Atomic Frequency Standard LI Ang, ZHOU Tiezhong, XUE Xiaobo, YI Hang, CHEN Dehao Journal of Astronautic Metrology and Measurement    2024, 44 (5): 39-44.   DOI: 10.12060/j.issn.1000-7202.2024.05.06 Abstract （61）      PDF（pc） （2407KB）（72）       Knowledge map    Save The stable operation of the hydrogen atomic frequency standard is the prerequisite for its important role,and the role of the Proportion Integration Differentiation (PID) control system is to adjust the output frequency of the crystal oscillator part of the hydrogen atomic frequency standard as close to its nominal value as possible,which is an important part of ensuring the stable operation of the hydrogen atomic frequency standard.Although the parameters of the PID control system will not change over time,their values are still mainly adjusted manually or decisions are made based on accumulated knowledge and a large amount of experimental data.Therefore,this paper adopts a new intelligent technology based on the Back Propagation (BP) neural network.The core of this algorithm is feedback adjustment based on the deviation between the output of the PID control system and the expected output.That is,in the back propagation process,feedback functions are used to better adapt to the situation in actual applications,and they are used as learning objects,so that the best performance can be achieved without external interference and the possibility and scope of deviation from expectations can be effectively reduced.The optimization of parameters in the PID control system is achieved through signal forward propagation and error reverse transmission.The final simulation result is that the daily frequency stability of the hydrogen atomic frequency standard is 1.51E-15.After experimental comparison,this method obtained optimal simulation data,thereby improving the stability of the hydrogen atomic frequency standard operation. Related Articles | Metrics | Comments（0）

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IoT and Blockchain Technology Empower the Digital Transformation of Measurement ZHENG Jianghui, LI Jingrui, GUO Hongyan, WU Hongxia, WANG Liang Journal of Astronautic Metrology and Measurement    2024, 44 (5): 81-85.   DOI: 10.12060/j.issn.1000-7202.2024.05.13 Abstract （68）      PDF（pc） （908KB）（70）       Knowledge map    Save A metrology management system supported by the Internet of Things and blockchain is proposed to address the quality management issues in the aerospace field and adapt to the development direction of digital transformation in metrology.The main research objective is to improve testing efficiency and ensure data security,focusing on the transmission of out of range values and customer data privacy issues.By integrating IoT technology and blockchain technology,the system achieves real-time data collection,device interconnection,and remote monitoring,while ensuring data immutability and privacy protection.Introduced smart contracts to automate the testing process,and combined with intelligent anomaly detection algorithms and equipment monitoring systems,the problem of out of range value transmission in the measurement process is effectively solved.The measurement management system empowered by the Internet of Things and blockchain technology can capture and process abnormal values in real time,and prevent potential risks of customer data leakage through the privacy protection mechanism of blockchain.This solution provides an efficient,safe,and automated feasible approach for quality management in the aerospace field,creating practical application value for enhancing the competitiveness of metrology testing and customer trust. Related Articles | Metrics | Comments（0）