Method and device for measuring dielectric parameters of loading medium of miniaturized cavity bubble system

Abstract

The invention belongs to the technical field of quantum frequency scale, dielectric constant and dielectric loss measurement, and particularly relates to a method and a device for measuring dielectric parameters of a loading medium of a miniaturized cavity bubble system. The method comprises the following steps: connecting a measurement device for loading dielectric parameters of a medium into a cavity bubble system in an atomic clock, and actually measuring the cavity bubble system by using the measurement device; the dielectric parameters comprise a dielectric constant and dielectric loss; the measuring device constructs a simulation model according to the state parameters of the cavity bubble system; parameter scanning analysis is carried out according to the simulation model, and relation images between dielectric parameters of an actual loading medium in the atomic clock and cavity bubble system simulation resonant frequency, an on-load Q value and a voltage standing wave ratio are obtained; and according to the actually measured resonant frequency, the load Q value and the voltage standing wave ratio, comparing the simulated resonant frequency and the simulated load Q value on the relation image, and determining the dielectric parameter value of the loading medium and the relation between the dielectric parameter value and the temperature.

Description

Technical Field

[0001] This invention belongs to the field of quantum frequency standard, dielectric constant and dielectric loss measurement technology, and particularly relates to a method and apparatus for measuring the dielectric parameters of the loaded medium in a miniaturized cavity bubble system. Background Technology

[0002] Miniaturized cavity clock systems are core components of the physics department of hydrogen and rubidium atomic clocks. Their performance directly determines the quality of atomic quantum transition spectral lines, thus affecting the accuracy and stability of the output frequency and other frequency characteristics of the miniaturized atomic clock. Factors such as the structure, shape, material, surface condition, electromechanical parameters, and environment of components like the microwave resonant cavity, storage bubble, and loading medium are the main reasons affecting the performance of the cavity clock system. Among these, the physical quantities of the loading medium, such as its structure, shape, and material, are particularly important.

[0003] The loading medium, as a component present in large quantities within the cavity, enables the miniaturization and lightweighting of the cavity bubble system. Its shape can be irregular, and its materials include Teflon, quartz, ceramic, or sapphire. The structure can be integrated or multi-segmented. Its dielectric parameters include a high dielectric constant and extremely low dielectric loss, ensuring that the microwave cavity does not decrease or only slightly loses its zero-load Q value after miniaturization. Therefore, its development is extremely challenging and its application requirements are very high. Due to the different dielectric parameters and temperature sensitivities of different materials, the design of the microwave cavity's structure, shape, materials, and environmental resistance varies, resulting in differences in the cavity bubble system's volume, weight, quantum transition spectral quality factor, and environmental immunity.

[0004] To optimize the design and fabrication of high-performance cavity-type atomic clocks, such as hydrogen atomic clocks, rubidium atomic clocks, and integrating sphere cold atomic clocks, it is necessary to accurately measure the dielectric parameters of the loaded medium and their variation with the environment under practical conditions. However, current methods for measuring dielectric parameters are rather idealistic. Taking dielectric constant as an example, the main approach is to measure the resonant frequency of a microwave resonant cavity containing a standard regular sample, and then construct an expression formula for the relationship between the resonant frequency and the dielectric constant to ultimately invert and measure the dielectric constant value. However, the measurement of dielectric loss requires selecting an appropriate method based on material properties, frequency range, and practical application scenarios. Strict limitations on sample size are also necessary; samples that are too large or too small lead to tuning difficulties.

[0005] The common drawbacks of dielectric parameter measurement methods are: high requirements for sample preparation, requiring uniform thickness and no defects; poor electrode contact can introduce significant errors; if the material absorbs moisture, it must be strictly dried, otherwise the loss will be falsely high and the dielectric constant will be inaccurate; high requirements for the test environment, as humidity and temperature fluctuations affect the polarization behavior of the material, requiring constant temperature and humidity control; power frequency electromagnetic noise may contaminate low-frequency measurement signals; and the theoretical model is simplified, with most methods assuming that the material is a linear and homogeneous medium, while actual materials may exhibit nonlinearity or anisotropy.

[0006] Since the measurement object is a microwave resonant cavity containing a sample, the sample and the resonant cavity may differ from the actual situation. Furthermore, the constructed dielectric parameter expression formula is a general model, not specifically designed for actual microwave resonant cavities and cavity bubble systems. As mentioned earlier, the structure, shape, material, surface condition, electromechanical parameters, and environment of components such as the microwave resonant cavity, storage bubble, and loading medium are the main factors affecting the performance of the cavity bubble system. Among these, the physical quantities such as the structure, shape, and material of the loading medium are particularly important. Therefore, the dielectric parameters obtained using a general model are not accurate. In addition, existing measurement schemes have high requirements for the measurement system, lack applicability and flexibility, and have certain limitations. Summary of the Invention

[0007] In view of this, the present invention provides a method and apparatus for measuring the dielectric parameters of a loading medium in a miniaturized cavity bubble system, which can improve the accuracy of measuring the dielectric parameters of the loading medium.

[0008] To solve the above-mentioned technical problems, the present invention is implemented as follows.

[0009] In a first aspect, embodiments of the present invention provide a method for measuring the dielectric parameters of a loaded medium in a miniaturized cavity bubble system, the method comprising:

[0010] A device for measuring the dielectric parameters of a miniaturized cavity bubble system is connected to the cavity bubble system in an atomic clock, and the cavity bubble system is measured using the device; the dielectric parameters include dielectric constant and dielectric loss.

[0011] The measuring device constructs a simulation model based on the state parameters of the cavity system. These state parameters are data from the actual components of the atomic clock, including the measurement environment, microwave resonant cavity, storage bulb, loading medium, tuner, and antenna coupling loop. Parameter types include temperature, structural dimensions, surface roughness, electrical parameters, and surface coating parameters. Based on the simulation model, parameter scanning analysis is performed to obtain graphs showing the relationship between the dielectric parameters of the actual loading medium in the atomic clock and the simulated resonant frequency, loaded Q value, and voltage standing wave ratio of the cavity system.

[0012] Based on the measured resonant frequency, loaded Q value, and voltage standing wave ratio, and comparing them with the simulated resonant frequency and simulated loaded Q value on the relationship graph, the dielectric parameters of the loaded medium are determined.

[0013] According to a preferred embodiment, in order to improve the accuracy of dielectric parameter measurement, the state parameters of the cavity bubble system can be kept constant, and the above operation can be repeated to achieve a statistical average through multiple measurements.

[0014] According to a preferred embodiment, the tuner position is changed and the above operation is repeated. By averaging multiple measurements, the accuracy of the measurement is improved.

[0015] According to a preferred embodiment, the temperature of the measurement environment is adjusted, and all operations are repeated to obtain the relationship between the dielectric parameters of the loaded medium and the temperature.

[0016] According to a preferred embodiment, the storage bubble is removed or the bubble system is evacuated before measurement.

[0017] Secondly, embodiments of the present invention provide a device for measuring the dielectric parameters of a loading medium in a miniaturized cavity clock system. The device includes: a vacuum constant temperature chamber, a network analyzer, a 10MHz frequency reference source, a simulation module, and a calculation module. The device is connected to the cavity clock system in the atomic clock under test. The cavity clock system consists of a microwave resonant cavity, a storage bubble, a loading medium, a tuner, and an antenna coupling loop.

[0018] Vacuum chambers are used to provide a vacuum measurement environment with different constant temperatures for bubble systems.

[0019] A network analyzer is used to analyze and obtain the resonant frequency, on-load Q value, and voltage standing wave ratio of a cavity bubble system based on its microwave power.

[0020] A 10MHz frequency reference source is used to generate a 10MHz frequency standard, which is then connected to and calibrated by a network analyzer.

[0021] The simulation module is used to construct a simulation model of the cavity bubble system based on the state parameters of the cavity bubble system; and to perform parameter scanning analysis based on the simulation model to obtain the relationship images between the dielectric parameters of the actual loaded medium in the atomic clock and the simulated resonant frequency, loaded Q value, and voltage standing wave ratio of the cavity bubble system; wherein, the state parameters are data of the actual components in the atomic clock, including the measurement environment, microwave resonant cavity, storage bubble, loaded medium, tuner, and antenna coupling loop; the parameter types include temperature, structural dimensions, surface roughness, electrical parameters, and surface coating parameters;

[0022] The calculation module is used to read the measured resonant frequency, loaded Q value and voltage standing wave ratio from the network analyzer, and determine the dielectric parameter values ​​of the loaded medium by comparing them with the simulated resonant frequency, loaded Q value and voltage standing wave ratio on the relationship graph.

[0023] According to a preferred embodiment, the state parameters of the cavity bubble system on which the simulation module constructs the simulation model include: the temperature of the measurement environment; the cavity structure of the microwave resonant cavity, the thickness, conductivity, and roughness of the cavity surface coating; the structure and surface roughness of the storage bubble; the structure and surface roughness of the loading medium; the structure, position, and surface coating thickness, conductivity, and roughness of the tuner; the structure of the antenna coupling loop and the surface coating thickness, conductivity, and roughness; the dielectric parameters of all materials; and the microwave power input to the cavity bubble system by the network analyzer.

[0024] According to a preferred embodiment, the calculation module further obtains multiple dielectric parameter values ​​at different resonant frequencies through multiple measurements for different tuner positions, and takes the average as the measurement result of the dielectric parameter of the loading medium.

[0025] According to a preferred embodiment, the method further includes: the antenna coupling loop, which is used as a measurement interface for measuring the resonant frequency, on-load Q value and voltage standing wave ratio of the cavity bubble system, and the number of such interfaces is two.

[0026] According to a preferred embodiment, the method further includes: the loading medium, as the component under test, may be made of ceramic, quartz, Teflon or sapphire, and its shape may be spherical, rectangular, ellipsoidal or cylindrical.

[0027] Beneficial effects:

[0028] (1) This invention provides a method and apparatus for measuring the dielectric parameters of a loaded medium in a miniaturized cavity bubble system. The method primarily measures the dielectric parameters of the loaded medium using a miniaturized cavity bubble system. It utilizes the actual cavity bubble system, resonant cavity, storage bubble, and loaded medium within an atomic clock, avoiding inaccuracies caused by using samples or external testing environments. Furthermore, the simulation model constructed in this invention is based on the actual testing environment and cavity bubble system. This invention analyzes the influence of various parameters of the environment, atomic clock, storage bubble, and loaded medium on the test, identifying the devices affecting the results, including the measurement environment, microwave resonant cavity, storage bubble, loaded medium, tuner, and antenna coupling loop. The types of influencing parameters include temperature, structural dimensions, surface roughness, electrical parameters, and surface coating parameters. This ensures that changes in dielectric parameters are accurately reflected in the simulation model. Using this simulation model, the relationship between resonant frequency, loaded Q value, and voltage standing wave ratio (VSWR) and dielectric parameters is constructed, enabling more realistic measurement of the dielectric parameters of the loaded medium. Simultaneously, the measurement data can be used as a reference to correct and compensate for the frequency shift of the atomic clock affected by temperature, thereby improving the temperature coefficient of the atomic clock and enhancing its environmental immunity.

[0029] (2) In order to eliminate the sources of measurement and modeling errors as much as possible, this invention fully considers the possibility that both dielectric constant and dielectric loss have an impact on the resonant frequency and Q value. It adopts a method of mutual comparison and verification of three measurement parameters based on resonant frequency, loaded Q value and voltage standing wave ratio, avoiding the use of resonant frequency or loaded Q value for measurement alone.

[0030] (3) In a preferred embodiment, the dielectric parameters of the loading medium and their variation with ambient temperature can be accurately measured under the practical condition of the loading medium. This solves the problem that the current method of measuring dielectric parameters by inverting the dielectric parameter formula using a general simplified model has high requirements for the measurement system, few model parameters, lack of flexibility and applicability, and certain limitations.

[0031] (4) Optimization of high-performance cavity systems in terms of structure, process and environmental adaptability is of great significance, especially in the development of advanced cavity system atomic clocks, such as space active hydrogen atomic clocks, POP rubidium atomic clocks and integrating sphere cold atomic clocks. Attached Figure Description

[0032] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0033] Figure 1 This is a schematic flowchart of a method for measuring the dielectric parameters of a loading medium in a miniaturized cavity bubble system, provided by an embodiment of the present invention.

[0034] Figure 2 This is a schematic diagram of a device for measuring the dielectric parameters of a loaded medium in a miniaturized cavity bubble system, provided in an embodiment of the present invention.

[0035] Figure 3 This is a schematic diagram of an S21 port curve image provided in an embodiment of the present invention;

[0036] Figure 4 This is a schematic diagram of the voltage standing wave ratio (VSWR) curve of port S21 provided in an embodiment of the present invention;

[0037] Figure 5 This is a schematic diagram of a dielectric parameter-resonant frequency surface image provided in an embodiment of the present invention;

[0038] Figure 6 This is a schematic diagram of a dielectric parameter-loaded Q-value surface image provided by an embodiment of the present invention;

[0039] Figure 7 This is a schematic diagram of a dielectric parameter-voltage standing wave ratio surface image provided by an embodiment of the present invention;

[0040] Among them, 1-vacuum constant temperature device, 2-cavity bubble system, 21-microwave resonant cavity, 22-storage bubble, 23-tuner, 24-antenna coupling loop, 25-loading medium, 3-network analyzer, 4-10MHz frequency reference source, 5-computer, 6-simulation software. Detailed Implementation

[0041] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0042] The following description and accompanying drawings fully illustrate specific embodiments of the invention to enable those skilled in the art to practice them.

[0043] It should be understood that the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0044] In the following description, when referring to the accompanying drawings, the same numbers in different drawings denote the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples of systems and methods consistent with some aspects of the invention as detailed in the appended claims.

[0045] In the description of this invention, it should be understood that the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances. Furthermore, in the description of this invention, unless otherwise stated, "multiple" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0046] The following will combine Figures 1-7 This invention provides a detailed description of a method and apparatus for measuring the dielectric parameters of a loading medium in a miniaturized cavity atomic clock. The following description uses a hydrogen clock as an example, but the invention can also be used to measure the dielectric parameters of the loading medium in cavity atomic clocks such as cesium clocks and rubidium clocks.

[0047] To achieve the functional effect of measuring the dielectric parameters of the loading medium in a miniaturized cavity bubble system, a method and apparatus for measuring the dielectric parameters of the loading medium in a miniaturized cavity bubble system, as well as the implementation process, have been invented, as follows:

[0048] S100, The measuring device for the dielectric parameters of the loading medium is connected to the cavity system in the hydrogen clock, and the loading medium in the cavity system is the object of measurement; the measuring device is started to obtain the measured resonant frequency, loaded Q value and voltage standing wave ratio of the hydrogen clock cavity system.

[0049] Before measurement, the bubble system can be evacuated to avoid the influence of other gases on the measurement, or the storage bubble can be removed to improve the accuracy of the initial measurement.

[0050] For example, such as Figure 2The diagram shows a device for measuring the dielectric parameters of a loaded medium in a miniaturized cavity clock system. The device mainly consists of a vacuum chamber 1, a network analyzer 3, a 10MHz frequency reference source 4, and a computer 5. This device is connected to the cavity clock system 2 within the hydrogen clock being tested. The cavity clock system 2 comprises a microwave resonant cavity 21, a storage bulb 22, a tuner 23, two antenna coupling loops 24, and a loaded medium 25. First, the cavity clock system 2 is placed in the vacuum chamber 1, which is an existing part of the hydrogen clock. In practice, an additional vacuum chamber can be used to control the ambient temperature. One of the antenna coupling loops 24 serves as the external interface of the cavity clock system 2 and is connected to the network analyzer 3. The network analyzer 3 is connected to the 10MHz frequency reference source 4 and the computer 5, respectively, thus forming the measuring device.

[0051] The measuring device is started, and the ambient temperature is set to T1 in the vacuum constant temperature chamber 1, with the vacuum degree less than or equal to the set vacuum degree P0. At this time, the gas inside and outside the loading medium 25 no longer affects the resonant frequency, on-load Q value, and voltage standing wave ratio of the cavity system 2. After the temperature reaches equilibrium, a two-port measurement method is used, connecting both antenna coupling loops 24 to the network analyzer 3. Then, the network analyzer 3 measures the following: Figures 3-4 The curves A1 and B1 of port S21 at temperature T1 are shown. The frequencies corresponding to the maximum values ​​of curves A1 and B1 are the measured resonant frequency f1 and the loaded Q value Q of the cavity bubble system 2, respectively. c1 Voltage standing wave ratio V2101.

[0052] In this case, the microwave resonant cavity 21 is a standard cylindrical waveguide resonant cavity; the storage bubble 22 is a spherical quartz glass bubble; the 10MHz frequency reference source 4 is a VCH 1003 hydrogen clock, used to generate a 10MHz high-stability frequency standard source, which is connected to the network analyzer 3 and calibrated to ensure the accuracy of frequency measurement; the computer 5 is used to acquire the measured resonant frequency, on-load Q value and voltage standing wave ratio based on the port S21 curve measured by the network analyzer 3.

[0053] S200, a simulation model is constructed based on the state parameters of the actual cavity bubble system.

[0054] For example, simulation software such as HFSS, CST and COMSOL can be used to build a simulation model of the cavity bubble system 2 on computer 5.

[0055] This invention analyzes the influence of various parameters of the environment, atomic clock, storage bubble, and loading medium on the test. It identifies the devices affecting the results, including the measurement environment, microwave resonant cavity, storage bubble, loading medium, tuner, and antenna coupling loop. The types of influencing parameters include temperature, structural dimensions, surface roughness, electrical parameters, and surface coating parameters. This allows changes in dielectric parameters to be accurately reflected in the simulation model. Using such a simulation model to construct the relationship between resonant frequency, loaded Q value, voltage standing wave ratio, and dielectric parameters enables more realistic measurement of the dielectric parameters of the loading medium.

[0056] In this preferred embodiment, the state parameters of the cavity bubble system 2 include: the temperature T1 of the ambient vacuum chamber; the cavity structure dimensions, surface coating thickness, conductivity, and roughness of the microwave resonant cavity 21; the structure dimensions and surface roughness of the storage bubble 22; the structure dimensions, position, surface coating thickness, conductivity, and roughness of the tuner 23; the structure dimensions, surface coating thickness, conductivity, and roughness of the antenna coupling ring 24; the loading medium 25; the dielectric parameters of the storage bubble 22 and the loading medium 25; and the microwave power input to the cavity bubble system 2 by the network analyzer 3. In this case, when constructing the simulation model, simulation software 6 is used to solve for the simulation resonant frequency, on-load Q value, and voltage standing wave ratio in the excitation model of HFSS.

[0057] S300, based on the simulation model, perform parameter scanning analysis to obtain the relationship images between the dielectric parameters of the loaded medium and the simulated resonant frequency, loaded Q value and voltage standing wave ratio of the cavity system.

[0058] For example, such as Figure 5 As shown, surface a1 represents the simulated resonant frequencies obtained by applying different dielectric parameters to the loaded medium 25 in the cavity bubble system 2 during simulation in computer 5. The planar coordinates of surface a1 represent the dielectric constant and dielectric loss, respectively, while the vertical coordinate represents the simulated resonant frequency. It is evident that surface a1 clearly shows the relationship between the dielectric parameters of the loaded medium 25 and the resonant frequencies of the cavity bubble system 2. Figure 6 As shown, surface b1 represents the simulated Q-values ​​under load obtained by applying different dielectric parameters to the loaded medium 25 in the cavity system 2 during simulation in computer 5. The planar coordinates of surface b1 represent the dielectric constant and dielectric loss, respectively, while the vertical coordinate represents the simulated Q-value under load. It is evident that surface b1 clearly shows the relationship between the dielectric parameters of the loaded medium 25 and the Q-values ​​under load in the cavity system 2. Figure 7As shown, surface c1 represents the simulated voltage standing wave ratios (VSWRs) obtained by applying different dielectric parameters to the loaded medium 25 in the cavity system 2 during simulation in computer 5. The planar coordinates of surface c1 represent the dielectric constant and dielectric loss in the dielectric parameters, and the vertical coordinate represents the simulated voltage standing wave ratio. It can be seen that surface c1 clearly shows the relationship between the dielectric parameters of the loaded medium 25 and the voltage standing wave ratio of the cavity system 2.

[0059] S400, based on the measured resonant frequency, loaded Q value, and voltage standing wave ratio, and referring to the resonant frequency, loaded Q value, and voltage standing wave ratio on the aforementioned relationship graph, determine the dielectric parameter values ​​of the loaded medium.

[0060] For example, the measured resonant frequency f1, on-load Q value Q01, and voltage standing wave ratio V2101 in step S100 are respectively compared with... Figures 6-7 The vertical coordinates of each point f1, Q01, and V1 on surfaces a1, b1, and c1, representing the simulated resonant frequency, loaded Q value, and voltage standing wave ratio, are (ε1, tanδ1). Thus, ε1 and tanδ1 are the actual values ​​of the dielectric constant and dielectric loss of the loading medium 25, respectively. Based on this, the dielectric parameters of the hydrogen clock storage loading medium 25 are measured.

[0061] S500: Change the position of the tuner in the cavity bubble system and repeat the above operation. Improve the accuracy of the measurement by averaging multiple measurements.

[0062] For example, keeping other state parameters of the cavity bubble system 2 unchanged, the resonant frequency and Q value of the cavity bubble system 2 will change when the tuner 23 is tuned to different positions. To achieve a second measurement, the S100-S400 process needs to be repeated to measure the dielectric parameters of the loading medium 25 at that position. By changing the position multiple times and taking multiple measurements, the average of the multiple measurements can yield a more accurate value for the dielectric parameters of the loading medium 25.

[0063] S600, load the storage bubble, repeat the above operation, and improve the accuracy of the measurement by statistical averaging through multiple measurements.

[0064] For example, keeping other state parameters of the cavity system 2 unchanged, the resonant frequency and Q value of the cavity system 2 will change when only the storage bubble 22 is introduced into the cavity system 2. In order to achieve the measurement again, it is necessary to repeat the S100-S500 process to measure the dielectric parameters of the loading medium 25 when the storage bubble 23 is loaded; in this way, after multiple operations and multiple measurements, the measured values ​​are statistically averaged to obtain a more accurate dielectric parameter value of the loading medium 25.

[0065] S700: Adjust the ambient temperature and repeat the above operation to analyze the relationship between the dielectric parameters of the loaded medium and the temperature.

[0066] For example, keeping other state parameters of the bubble system 2 unchanged, but changing the temperature of the vacuum chamber 1 from T1 to T2, the resonant frequency and Q value of the bubble system 2 will change. To achieve a second measurement, the S100-S600 process needs to be repeated, and the values ​​at ambient temperature T2 can be measured. Figures 3-4 The S21 curves A2 and B2 shown, and as shown in the figure Figures 5-7 The dielectric parameters and resonant frequency surface a2, dielectric parameters and loaded Q value surface b2, and dielectric parameters and voltage standing wave ratio surface c2 are shown. Simulated values ​​f2, Qc2, and V2 are obtained, thus yielding the corresponding measured resonant frequency f2, loaded Q value Q02, and voltage standing wave ratio V2, which can then be compared with… Figures 5-7 The dielectric parameters (ε2, tanδ2) of the loading medium 25 are obtained. By repeatedly changing the temperature setpoint of the vacuum constant temperature chamber 1 and repeating the above process, the law of change of dielectric constant of loading medium 25 with temperature can be obtained after multiple measurements.

[0067] Through the above case study, to achieve the desired measurement of the dielectric parameters of the loaded medium in a miniaturized cavity system, this method primarily focuses on the hydrogen clock cavity system 2. By measuring the resonant frequency, loaded Q value, and voltage standing wave ratio (VSWR), and constructing simulation models depicting the relationships between these parameters and the dielectric parameters, a more realistic measurement of the dielectric parameters of the loaded medium 25 is achieved. This method, because it can accurately measure the dielectric constant of the loaded medium 25 and its variation with ambient temperature under practical conditions, overcomes the limitations of current methods that rely on finite samples and simple calculation formulas for dielectric parameter measurement. These methods have high requirements for the measurement system, too few model parameters, and lack flexibility and applicability. This method and device are of great significance for the optimized design of high-performance cavity systems in terms of structure, manufacturing process, environmental adaptability, and reliability, especially in the development of advanced cavity system atomic clocks such as space active hydrogen atomic clocks, POP rubidium atomic clocks, and integrating sphere cold atomic clocks.

[0068] It should be noted that the apparatus for measuring the dielectric parameters of a loaded medium provided in the above embodiments is only illustrated by the division of the functional modules described above when executing the method for measuring the dielectric parameters of a loaded medium. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. In addition, the method and apparatus embodiments for measuring the dielectric parameters of a loaded medium provided in the above embodiments belong to the same concept, and the implementation process is detailed in the method embodiments, which will not be repeated here.

[0069] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0070] The specific embodiments described above only illustrate the design principles of the present invention. The shapes and names of the components in this description may differ and are not limited. Therefore, those skilled in the art can modify or make equivalent substitutions to the technical solutions described in the foregoing embodiments; and these modifications and substitutions do not depart from the inventive spirit and technical solutions of the present invention, and should all fall within the protection scope of the present invention.

Claims

1. A method for measuring the dielectric parameters of a loaded medium in a miniaturized cavity bubble system, characterized in that, The method includes: A device for measuring the dielectric parameters of a miniaturized cavity bubble system is connected to the cavity bubble system in an atomic clock, and the cavity bubble system is measured using the device; the dielectric parameters include dielectric constant and dielectric loss. The measuring device constructs a simulation model based on the state parameters of the cavity system. These state parameters are data from the actual components of the atomic clock, including the measurement environment, microwave resonant cavity, storage bulb, loading medium, tuner, and antenna coupling loop. Parameter types include temperature, structural dimensions, surface roughness, electrical parameters, and surface coating parameters. Based on the simulation model, parameter scanning analysis is performed to obtain graphs showing the relationship between the dielectric parameters of the actual loading medium in the atomic clock and the simulated resonant frequency, loaded Q value, and voltage standing wave ratio of the cavity system. Based on the measured resonant frequency, loaded Q value, and voltage standing wave ratio, and comparing them with the simulated resonant frequency and simulated loaded Q value on the relationship graph, the dielectric parameters of the loaded medium are determined.

2. The method for measuring the dielectric parameters of a loaded medium in a miniaturized cavity bubble system according to claim 1, characterized in that, Keeping the state parameters of the bubble system constant, repeat the above method and average the results through multiple measurements.

3. The method for measuring the dielectric parameters of a loaded medium in a miniaturized cavity bubble system according to claim 1, characterized in that, Change the tuner position and repeat the above method, then take multiple measurements and average the results.

4. The method for measuring the dielectric parameters of a loaded medium in a miniaturized cavity bubble system according to claim 1, characterized in that, Adjust the temperature of the measurement environment and repeat the above method to obtain the relationship between the dielectric parameters of the loaded medium and the temperature.

5. The method for measuring the dielectric parameters of a loaded medium in a miniaturized cavity bubble system according to claim 1, characterized in that, Before measurement, evacuate the bubble system or remove the stored bubble.

6. The method for measuring the dielectric parameters of a loaded medium in a miniaturized cavity bubble system according to claim 1, characterized in that, When constructing the simulation model, the excitation model in the simulation software is used to solve for the simulation resonant frequency, on-load Q value, and voltage standing wave ratio.

7. A device for measuring the dielectric parameters of a loaded medium in a miniaturized cavity bubble system, characterized in that, The device includes: a vacuum constant temperature chamber, a network analyzer, a 10MHz frequency reference source, a simulation module, and a calculation module; the device is connected to the cavity bubble system in the atomic clock under test, which consists of a microwave resonant cavity, a storage bubble, a loading medium, a tuner, and an antenna coupling loop; Vacuum chambers are used to provide a vacuum measurement environment with different constant temperatures for bubble systems. The input to the network analyzer is the microwave power of the cavity bubble system, which is used to analyze and obtain the resonant frequency, on-load Q value and voltage standing wave ratio of the cavity bubble system based on the microwave power of the cavity bubble system. A 10MHz frequency reference source is used to generate a 10MHz frequency standard, which is then connected to and calibrated by a network analyzer. The simulation module is used to construct a simulation model of the cavity bubble system based on the state parameters of the cavity bubble system; and to perform parameter scanning analysis based on the simulation model to obtain the relationship images between the dielectric parameters of the actual loaded medium in the atomic clock and the simulated resonant frequency, loaded Q value, and voltage standing wave ratio of the cavity bubble system; wherein, the state parameters are data of the actual components in the atomic clock, including the measurement environment, microwave resonant cavity, storage bubble, loaded medium, tuner, and antenna coupling loop; the parameter types include temperature, structural dimensions, surface roughness, electrical parameters, and surface coating parameters; The calculation module is used to read the measured resonant frequency, loaded Q value and voltage standing wave ratio from the network analyzer, and determine the dielectric parameter values ​​of the loaded medium by comparing them with the simulated resonant frequency, loaded Q value and voltage standing wave ratio on the relationship graph.

8. The apparatus for measuring the dielectric parameters of a loaded medium in a miniaturized cavity bubble system according to claim 7, characterized in that, The simulation module constructs the simulation model based on the state parameters of the cavity bubble system, including: the temperature of the measurement environment; the cavity structure of the microwave resonant cavity, the thickness, conductivity, and roughness of the cavity surface coating; the structure and surface roughness of the storage bubble; the structure and surface roughness of the loading medium; the structure, location, and surface coating thickness, conductivity, and roughness of the tuner; the structure of the antenna coupling loop and the surface coating thickness, conductivity, and roughness; and the dielectric parameters of all materials.

9. The apparatus for measuring the dielectric parameters of a loaded medium in a miniaturized cavity bubble system according to claim 7, characterized in that, The calculation module further obtains multiple dielectric parameter values ​​at different resonant frequencies through multiple measurements for different tuner positions, and takes the average as the measurement result of the dielectric parameter of the loading medium.

10. The apparatus for measuring the dielectric parameters of a loaded medium in a miniaturized cavity bubble system according to claim 7, characterized in that, The loading medium, as the component under test, is made of ceramic, quartz, Teflon or sapphire, and its shape can be spherical, rectangular, ellipsoidal or cylindrical.

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