Resonant cavity performance parameter determination method, apparatus and system, and computer device

Abstract

The invention relates to a resonant cavity performance parameter determination method, device and system and computer equipment. The method comprises the following steps: acquiring a signal transmission parameter relationship of a resonant cavity and a signal transmission characteristic coefficient of the resonant cavity under a characteristic frequency; for each to-be-sampled microwave signal frequency, based on a difference between the signal transmission characteristic coefficient and an initial transmission coefficient collected for the resonant cavity under the microwave signal frequency, determining a sampling frequency under the microwave signal frequency; acquiring a plurality of candidate transmission coefficients of the resonant cavity under the microwave signal frequency according to the sampling times; based on each candidate transmission coefficient, determining a corresponding signal transmission coefficient of the resonant cavity under the microwave signal frequency; and based on the signal transmission parameter relationship, fitting the signal transmission coefficients corresponding to the microwave signal frequencies, and obtaining the performance parameters of the resonant cavity under the condition of fitting error convergence. By adopting the method, the analysis accuracy of the performance parameters of the resonant cavity can be improved.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the field of quantum computing, and in particular, to a resonant cavity performance parameter determination method, device and system, and a computer device. BACKGROUND

[0002] A resonant cavity is a physical structure capable of storing and enhancing electromagnetic waves of specific frequencies, usually composed of metal or superconducting materials with specific geometric shapes, which forms a standing wave through boundary conditions to achieve efficient energy storage.

[0003] With the rapid development of quantum computing technology, superconducting quantum computing has attracted much attention due to its good scalability and process compatibility. The non-destructive readout of superconducting qubits relies on the dispersive coupling of superconducting resonant cavities, therefore, the performance of the resonant cavity is crucial for the readout of the quantum bit, and a high-performance resonant cavity can achieve faster and higher-fidelity quantum measurements, which is essential for improving the overall performance of the quantum computer.

[0004] However, there is a problem of low analysis accuracy when analyzing the performance parameters of the resonant cavity. SUMMARY

[0005] Therefore, it is necessary to solve the above technical problems, and the present disclosure provides a resonant cavity performance parameter determination method, device and system, and a computer device capable of improving the analysis accuracy of the performance parameters of the resonant cavity.

[0006] In a first aspect, the present disclosure provides a resonant cavity performance parameter determination method, the resonant cavity being used for measuring a quantum bit. The method comprises: obtaining a signal transmission parameter relationship of the resonant cavity, and a signal transmission characteristic coefficient of the resonant cavity at a characteristic frequency, wherein the signal transmission parameter relationship is used to characterize the relationship between the signal transmission coefficient of the resonant cavity and the microwave signal frequency and performance parameters of the resonant cavity; for each microwave signal frequency to be sampled, determining the sampling number at the microwave signal frequency based on the difference between the signal transmission characteristic coefficient and the initial transmission coefficient collected for the resonant cavity at the microwave signal frequency; collecting a plurality of candidate transmission coefficients of the resonant cavity at the microwave signal frequency according to the sampling number; determining the corresponding signal transmission coefficient of the resonant cavity at the microwave signal frequency based on each candidate transmission coefficient; fitting the corresponding signal transmission coefficients at each microwave signal frequency based on the signal transmission parameter relationship, and obtaining the performance parameters of the resonant cavity in the case of fitting error convergence.

[0007] Based on the method provided in the first aspect, on the one hand, by adaptively determining the sampling number corresponding to the microwave signal frequency, compared with the imbalance of signal-to-noise ratio caused by the fixed average number of scanning mode, the performance analysis accuracy of the resonant cavity can be improved. On the other hand, by fitting the parameters based on the pre-set signal transmission parameter relationship, the analysis efficiency of the performance parameters of the resonant cavity can be improved.

[0008] Optionally, based on the difference between the signal transmission characteristic coefficient and the initial transmission coefficient collected for the resonant cavity under the microwave signal frequency, the sampling number under the microwave signal frequency is determined, comprising: obtaining the initial transmission coefficient collected for the resonant cavity under the microwave signal frequency, and the upper limit of the sampling number; based on the difference between the signal transmission characteristic coefficient and the initial transmission coefficient, the signal-to-noise ratio under the microwave signal frequency is determined; the smaller value between the sampling number matched with the signal-to-noise ratio and the upper limit of the sampling number is determined as the sampling number under the microwave signal frequency.

[0009] Based on the above optional content, by determining the sampling number under the microwave signal frequency based on the sampling number matched with the signal-to-noise ratio under the microwave signal frequency, the determination accuracy of the sampling number can be improved in the case of considering the upper limit of the sampling number.

[0010] Optionally, the performance parameters include the resonance frequency, the total quality factor, the internal quality factor and the external quality factor; based on the signal transmission parameter relationship, the signal transmission coefficients respectively corresponding to each microwave signal frequency are fitted, and the performance parameters of the resonant cavity are obtained in the case of fitting error convergence, comprising: obtaining the signal transmission inverse parameter relationship by inverting the signal transmission parameter relationship; based on the signal transmission parameter relationship, each signal transmission coefficient is fitted, and the resonance frequency and the total quality factor of the resonant cavity are obtained in the case of fitting error convergence; based on the signal transmission inverse parameter relationship, the signal transmission inverse coefficient corresponding to each signal transmission coefficient is fitted, and the internal quality factor of the resonant cavity is obtained in the case of fitting error convergence; the signal transmission inverse coefficient corresponding to any signal transmission coefficient is obtained by inverting the signal transmission coefficient; the performance parameters including the resonance frequency, the total quality factor, the internal quality factor and the external quality factor are obtained; the external quality factor is determined according to the total quality factor and the internal quality factor.

[0011] Based on the above optional content, by obtaining the total quality factor based on the signal transmission parameter relationship and the internal quality factor based on the signal transmission inverse parameter relationship, the fitting can be performed in steps, which can avoid the direct fitting of 7 parameters, effectively reduce the size of the fitting parameter space and the difficulty of initial value selection, and improve the accuracy of the performance analysis of the resonant cavity.

[0012] Optionally, based on the signal transmission parameter relationship, the signal transmission coefficients are fitted, and the resonance frequency and the total quality factor of the resonant cavity are obtained in the case of fitting error convergence, including: eliminating the phase accumulation caused by the electrical delay, obtaining the signal transmission correction parameter relationship corresponding to the signal transmission parameter relationship, and the signal transmission correction coefficient corresponding to each signal transmission coefficient respectively; based on the projection positions of each signal transmission correction coefficient in the complex space, the first signal phase corresponding to each microwave signal frequency is determined; the signal transmission correction parameter relationship is converted to obtain the corresponding first phase change parameter relationship; the first phase change parameter relationship is used to represent the relationship between the first signal phase, the total quality factor, the microwave signal frequency and the first resonance frequency; based on the first phase change parameter relationship, the first signal phase corresponding to each microwave signal frequency is phase fitted to obtain the first initial value of the resonance frequency and the initial value of the total quality factor of the resonant cavity; taking the first initial value of the resonance frequency and the initial value of the total quality factor as the initial value, based on the signal transmission parameter relationship, the signal transmission coefficients are fitted, and the resonance frequency and the total quality factor of the resonant cavity are obtained in the case of fitting error convergence.

[0013] Based on the above optional content, by eliminating the phase accumulation caused by the electrical delay, the influence of the phase accumulation on the resonance frequency and the total quality factor of the resonant cavity can be avoided, and then based on the signal transmission correction parameter relationship obtained after eliminating the phase accumulation caused by the electrical delay and based on the first phase change parameter relationship corresponding to the signal transmission correction parameter relationship, the resonance frequency and the total quality factor of the resonant cavity are determined, which can improve the accuracy of the obtained resonance frequency and total quality factor.

[0014] Optionally, the process of obtaining the signal transmission correction coefficient corresponding to each signal transmission coefficient includes: based on the projection positions of each signal transmission correction coefficient in the complex space, an original curve is obtained; selecting a plurality of feature points in the original curve which satisfy the interval condition between the data interval and the end, linearly fitting the phase corresponding to each feature point to obtain an electrical delay initial value; taking the electrical delay initial value as the fitting initial value, taking the standard deviation of the distance between each feature point and the center of the first fitting circle as the fitting loss, based on the projection positions of each signal transmission coefficient, the circle fitting is performed, and in the case of fitting loss convergence, the electrical delay of the resonant cavity is obtained; for each signal transmission coefficient, the phase accumulation caused by the electrical delay is offset based on the signal transmission coefficient to obtain the signal transmission correction coefficient corresponding to the signal transmission coefficient.

[0015] Based on the above optional content, by correcting the projection position of each signal transmission correction coefficient in the complex space, the original curve is obtained, and then in the case of considering the standard deviation of the distance between the two end data of the original curve and the center of the first fitting circle, the fitting accuracy of the electrical delay parameter can be improved by removing the phase accumulation caused by the electrical delay.

[0016] Optionally, based on the respective projection positions of the signal transmission correction coefficients in the complex space, the first signal phase corresponding to each microwave signal frequency is determined, including: performing circular fitting processing based on the respective projection positions of the signal transmission correction coefficients in the complex space to obtain a first fitting circle; taking the center of the first fitting circle as a new coordinate origin, updating the respective first coordinate information of the signal transmission correction coefficients in the complex space; and determining the first signal phase corresponding to each microwave signal frequency based on the updated first coordinate information.

[0017] Based on the above optional content, by using circular fitting to fit the respective projection positions of the signal transmission correction coefficients in the complex space, the respective projection positions of the signal transmission correction coefficients in the complex space can be considered as a whole, and thus by updating the respective first coordinate information of the signal transmission correction coefficients in the complex space based on the circular fitting result, the determination accuracy of the first signal phase corresponding to each microwave signal frequency can be improved.

[0018] In a second aspect, the present disclosure also provides a resonant cavity performance parameter determination device. The resonant cavity is used for measuring a quantum bit. The device comprises: an acquisition module configured to acquire a signal transmission parameter relationship of the resonant cavity and a signal transmission characteristic coefficient of the resonant cavity at a characteristic frequency; the signal transmission parameter relationship is used to represent a relationship between a signal transmission coefficient of the resonant cavity and a microwave signal frequency and a performance parameter of the resonant cavity; a determination module configured to, for each microwave signal frequency to be sampled, determine a sampling number at the microwave signal frequency based on a difference between the signal transmission characteristic coefficient and an initial transmission coefficient collected for the resonant cavity at the microwave signal frequency; a collection module configured to collect a plurality of candidate transmission coefficients of the resonant cavity at the microwave signal frequency according to the sampling number; an analysis module configured to determine a signal transmission coefficient corresponding to the resonant cavity at the microwave signal frequency based on each candidate transmission coefficient; and a processing module configured to fit the signal transmission coefficients corresponding to each microwave signal frequency based on the signal transmission parameter relationship, and obtain the performance parameter of the resonant cavity in the case of fitting error convergence.

[0019] In a third aspect, the present disclosure provides a resonant cavity performance parameter determination system, the resonant cavity being used for measuring a quantum bit, the system comprising a processor, a microwave generator and a microwave collector; the processor being connected to the microwave generator and the microwave collector; the microwave generator being configured to input a first microwave signal into the resonant cavity; the microwave collector being configured to receive a second microwave signal output by the resonant cavity; a signal ratio between the second microwave signal and the first microwave signal being used to represent a transmission coefficient of the resonant cavity; and the processor being configured to implement the method of the first aspect or any one of the first aspect.

[0020] In a fourth aspect, the present disclosure also provides a computer device. The computer device comprises a memory and a processor, the memory storing a computer program, and the processor implementing the resonant cavity performance parameter determination method described above when executing the computer program.

[0021] In a fifth aspect, the present disclosure also provides a computer readable storage medium. The computer readable storage medium stores a computer program, and the computer program is executed by a processor to implement the resonant cavity performance parameter determination method described above.

[0022] In a sixth aspect, the present disclosure also provides a computer program product. The computer program product comprises a computer program, and the computer program is executed by a processor to implement the resonant cavity performance parameter determination method described above.

[0023] The resonant cavity performance parameter determination method, device and system, and the computer device described above, by obtaining the signal transmission parameter relationship of the resonant cavity and the signal transmission characteristic coefficient of the resonant cavity at the characteristic frequency, for each microwave signal frequency to be sampled, based on the difference between the signal transmission characteristic coefficient and the initial transmission coefficient collected for the resonant cavity at the microwave signal frequency, determining the sampling number at the microwave signal frequency, and according to the sampling number, collecting a plurality of candidate transmission coefficients of the resonant cavity at the microwave signal frequency, based on each candidate transmission coefficient, determining the corresponding signal transmission coefficient of the resonant cavity at the microwave signal frequency, and then, based on the signal transmission parameter relationship, fitting the signal transmission coefficients respectively corresponding to each microwave signal frequency, obtaining the performance parameter of the resonant cavity in the case of fitting error convergence. Thus, on the one hand, by adaptively determining the sampling number corresponding to the microwave signal frequency, compared with the unbalanced signal-to-noise ratio caused by the fixed average number of scanning, the performance analysis accuracy of the resonant cavity can be improved. On the other hand, by fitting the parameters based on the pre-set signal transmission parameter relationship, the analysis efficiency of the performance parameters of the resonant cavity can be improved. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 A schematic diagram for measuring the state change of a quantum bit by using a resonant cavity in an embodiment;

[0025] Figure 2A flowchart of a method for determining a performance parameter of a resonant cavity in an embodiment;

[0026] Figure 3 A flowchart of a method for obtaining a sequence of signal transmission coefficients in an embodiment;

[0027] Figure 4 A diagram of data distribution in a complex space in an embodiment;

[0028] Figure 5 A diagram of fitting results in an embodiment;

[0029] Figure 6 A diagram of fitting results in another embodiment;

[0030] Figure 7 A diagram of fitting results in another embodiment;

[0031] Figure 8 A diagram of fitting results in another embodiment;

[0032] Figure 9 A flowchart of a method for determining a performance parameter of a resonant cavity in another embodiment;

[0033] Figure 10 A diagram of fitting results in another embodiment;

[0034] Figure 11 A diagram of fitting results in another embodiment;

[0035] Figure 12 A diagram of fitting results in another embodiment;

[0036] Figure 13 A diagram of fitting results in another embodiment;

[0037] Figure 14 A flowchart of a method for determining a performance parameter of a resonant cavity in another embodiment;

[0038] Figure 15 A block diagram of a system for determining a performance parameter of a resonant cavity in an embodiment;

[0039] Figure 16 A block diagram of an apparatus for determining a performance parameter of a resonant cavity in an embodiment;

[0040] Figure 17 An internal structure diagram of a computer device in an embodiment. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solutions and advantages of the present disclosure clearer, the present disclosure will be further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present disclosure and not to limit the present disclosure.

[0042] In a superconducting quantum computer, a resonant cavity plays an important role. First, the resonant cavity is used to couple with a superconducting quantum bit to form a cavity quantum electrodynamics (cQED) system. This coupling mechanism enables the quantum bit and the electromagnetic field to interact coherently, thereby realizing the state reading, manipulation and interconnection of the quantum bit. Second, the resonant cavity can also be used as a quantum information storage unit to store quantum states in the cavity mode and prolong the life of the information. Through its high quality factor and precise frequency control, the resonant cavity is used to realize high-fidelity quantum state manipulation and coupling network of multiple quantum bits.

[0043] The non-destructive reading of a superconducting quantum bit relies on a resonant cavity coupled with it in a dispersive manner. When the superconducting quantum bit is in different states, the cavity frequency of the resonant cavity is displaced in a dispersive manner. By measuring the change in amplitude or phase of the signal of the resonant cavity, the state of the quantum bit can be obtained. Therefore, the performance of the resonant cavity is crucial for the reading of the quantum bit, and a high-performance resonant cavity can realize faster and higher-fidelity quantum measurement.

[0044] In microwave measurement, the signal of the resonant cavity represents the transmission coefficient from the input port (i.e. port 1) to the output port (i.e. port 2), i.e. the change in amplitude and phase of the signal transmitted from the input port to the output port, which is represented as:

[0045]

[0046] wherein, is a complex microwave signal from the signal source into port 1, is a complex microwave signal output from port 2, is a complex signal containing amplitude and phase information, is expressed in logarithmic form (such as dB) or in complex space. In the measurement of the resonant cavity, the change of can reflect the resonance characteristics of the resonant cavity. By measuring the signal of , the resonant frequency, quality factor (Q value) and energy loss characteristics of the resonant cavity can be analyzed.

[0047] ​​The quality factor (Q value) is used to determine the relationship between energy storage and energy loss of a resonant system at the resonance frequency. The quality factor is the ratio of the stored energy to the lost energy of the resonant system, and reflects the loss characteristics of the resonant system and the ability to enhance signals of a specific frequency. The higher the Q value, the smaller the loss of the resonant system, the longer the energy storage time, and the stronger the selectivity to the specific frequency; the lower the Q value, the greater the loss of the resonant system, and the wider the frequency response.

[0048] In some embodiments, the quality factor can include an internal quality factor, an external quality factor, and a total quality factor, which satisfy:

[0049]

[0050] wherein, represents the total quality factor. represents the internal quality factor, which is related to the material loss of the resonant cavity itself, including conductor loss, dielectric loss, and the influence of surface defects, and reflects the inherent energy loss of the resonant cavity. represents the external quality factor, which is determined by the energy exchange efficiency between the resonant cavity and the coupler, and is affected by the coupler design and the coupling strength, and reflects the degree of interaction between the resonant cavity and the outside world.

[0051] The role of measuring the quality factor includes: on the one hand, a higher quality factor indicates that when the quantum bit state changes, a larger discrimination can be brought by the dispersion shift under the same coupling strength, thereby obtaining a higher signal-to-noise ratio when measuring a superconducting quantum bit, as shown in Figure 1 The present disclosure provides a schematic diagram for measuring the state change of a quantum bit using a resonant cavity. On the other hand, by measuring the internal quality factor, defects, impurities and material damage that may be introduced during the chip manufacturing process can be evaluated, and by measuring the external quality factor, the load state of the resonant cavity can be judged, and the chip design rationality and processing precision can be evaluated.

[0052] In some embodiments, the complex microwave signal of the resonant cavity can be collected at different microwave signal frequencies f, specifically the complex microwave signal transmitted from the signal source to the input port at the microwave signal frequency f is collected, and the complex microwave signal output from the output port at the microwave signal frequency f is collected, based on the total quality factor Qtotal can be obtained ; and then the formula shown below is used for fitting:

[0053]

[0054] wherein, and Here are the performance parameters of the resonant cavity, namely the overall quality factor and the equivalent external quality factor, respectively. It is important to note that... Considering the equivalent external quality factor after port impedance correction, its relationship with the total quality factor and internal quality factor is as follows:

[0055]

[0056] In the above fitting process, if a fixed average number of scans is used for measurement... The microwave signal frequency can cause a signal-to-noise ratio (SNR) imbalance, meaning that the signal amplitude near the resonant frequency of the resonant cavity is extremely low, resulting in a very poor SNR, and weak signals may be drowned out by noise. Since the signal near the resonant frequency is critical data, it affects the extraction accuracy of key parameters such as the resonant cavity frequency and quality factor, reducing the accuracy of resonant cavity performance analysis. Furthermore, with a fixed number of averaging iterations, increasing the number of iterations leads to over-averaging of high-amplitude frequency regions (such as those far from the resonant frequency), prolonging measurement time and reducing testing efficiency.

[0057] Moreover, in the above fitting process, the fitting parameters have too much freedom, including 7 variables, namely... If the initial values ​​for one or more variables are set with a large deviation, it will be difficult to achieve a good fit. Furthermore, when... and When the difference is small, because and Too close, and it's difficult to obtain effective results. value.

[0058] In one embodiment, this disclosure provides a method for determining resonant cavity performance parameters, with an example illustrating the application of this method to a processor in a resonant cavity performance parameter determination system. Figure 2 As shown, the following steps may be included:

[0059] S202, obtain the signal transmission parameter relationship of the resonant cavity and the signal transmission characteristic coefficient of the resonant cavity at the characteristic frequency.

[0060] The signal transmission parameter relationship is used to characterize the relationship between the signal transmission coefficient of the resonant cavity and the microwave signal frequency and performance parameters of the resonant cavity. For example, the signal transmission parameter relationship satisfies:

[0061]

[0062] In the relationship of signal transmission parameters, The background attenuation amplitude of the measurement loop can be determined by microwave cables, attenuators, filters, amplifiers, etc. The background phase of the measurement loop, which can be determined by the microwave cable, attenuator, filter, amplifier, etc. The microwave signal frequency, The time for the microwave signal to propagate from the transmitting port to the receiving port, i.e., the electrical delay; The phase generated by the impedance mismatch of the input port and the output port of the resonant cavity, The resonant frequency of the resonant cavity, which is related to the physical structure parameters of the resonant cavity; And The performance parameters of the resonant cavity are the total quality factor and the equivalent external quality factor, respectively; and the signal transmission coefficient of the resonant cavity is .

[0063] wherein the characteristic frequency refers to a frequency near the resonant frequency of the resonant cavity, the characteristic frequency has a certain frequency difference from the resonant frequency of the resonant cavity, and the frequency difference between the characteristic frequency and the resonant frequency of the resonant cavity satisfies a difference condition. For example, when the frequency difference is less than or equal to a preset frequency difference threshold, it is determined that the frequency difference satisfies the difference condition. The specific value of the frequency difference threshold can be set based on actual application.

[0064] In some embodiments, the resonant frequency of the resonant cavity can be read from the information of the resonant cavity. That is, the information of the resonant cavity can be determined from the design of the resonant cavity, and the information can include the resonant frequency of the resonant cavity.

[0065] In some embodiments, the resonant frequency of the resonant cavity can be determined based on calculation or simulation, etc. For example, the resonant frequency of the resonant cavity can be calculated or simulated according to the length, width, distance to ground, etc. of the co-planar waveguide transmission line in the design layout of the resonant cavity.

[0066] In some embodiments, considering that the resonant frequency of the resonant cavity can be affected by various environmental factors, such as temperature, pressure, humidity of medium, etc., based on this, the resonant frequency of the resonant cavity can be obtained through experimental calibration according to the environmental factors of the environment in which the resonant cavity is located based on calculation or simulation.

[0067] In some embodiments, the signal transmission coefficient of the resonant cavity at the characteristic frequency can be obtained by measuring N times at the characteristic frequency, and obtaining the first microwave signal and the second microwave signal for each measurement; and the mean or median of the signal transmission coefficients obtained by N times of measurement is determined as the signal transmission characteristic coefficient of the resonant cavity at the characteristic frequency. For example, The characteristic frequency is represented by f0, and the N signal transmission coefficients are represented by The signal transmission coefficient obtained by each measurement is represented by The same or different, the mean of the N signal transmission coefficients can be determined as the signal transmission characteristic coefficient .

[0068] S204, for each microwave signal frequency to be sampled, determining the number of samplings at the microwave signal frequency based on the difference between the signal transmission characteristic coefficient and the initial transmission coefficient collected for the resonant cavity at the microwave signal frequency.

[0069] wherein the microwave signal frequency refers to a frequency in the preset frequency interval. For example, the microwave signal frequency can be randomly selected from the preset frequency interval, or the microwave signal frequency can be selected from the preset frequency interval based on a fixed frequency interval, and the frequency difference between adjacent microwave signal frequencies in the preset frequency interval is the same as the fixed frequency interval. The characteristic frequency is within the preset frequency interval, for example, the frequency difference between the upper limit and the lower limit of the preset frequency interval is less than the preset frequency difference, i.e., the preset frequency interval refers to a small frequency deviation range near the characteristic frequency, for example, if the characteristic frequency is 5.8 GHz, the preset frequency interval can be [5.795 GHz, 5.805 GHz].

[0070] wherein the signal ratio between the second microwave signal and the first microwave signal is used to represent the transmission coefficient of the resonant cavity, and the transmission coefficient can also include the initial transmission coefficient collected for the resonant cavity at the microwave signal frequency. Specifically, based on the signal ratio between the second microwave signal and the first microwave signal matching the microwave signal frequency, the initial transmission coefficient collected for the resonant cavity at the microwave signal frequency is obtained. Further, the number of samplings at the microwave signal frequency can be determined based on the difference between the signal transmission characteristic coefficient and the initial transmission coefficient collected for the resonant cavity at the microwave signal frequency.

[0071] wherein the implementation of determining the number of samplings at the microwave signal frequency based on the difference between the signal transmission characteristic coefficient and the initial transmission coefficient collected for the resonant cavity at the microwave signal frequency for each microwave signal frequency to be sampled is not limited, and several implementation manners are exemplified below.

[0072] In one implementation manner, the coefficient difference value between the signal transmission characteristic coefficient and the initial transmission coefficient collected for the resonant cavity at the microwave signal frequency is determined; when the coefficient difference value is greater than or equal to a preset difference value, the first preset number is determined as the number of samplings at the microwave signal frequency; when the coefficient difference value is less than the preset difference value, the second preset number is determined as the number of samplings at the microwave signal frequency. Wherein the first preset number is less than the second preset number. Wherein the first preset number and the second preset number are both preset numbers, and the specific values can be set according to the actual application scenario.

[0073] In one implementation manner, according to the theoretical parameter relationship of the noise, the signal-to-noise ratio (SNR) is proportional to N is the sampling number corresponding to the microwave signal frequency, therefore, if the signal-to-noise ratio of each microwave signal frequency is improved to the signal-to-noise ratio away from the resonant frequency of the resonant cavity, the sampling number under the microwave signal frequency can be determined by the following steps, including:

[0074] S11, obtaining the initial transmission coefficient collected for the resonant cavity under the microwave signal frequency, and the upper limit of the sampling number.

[0075] For example, The initial transmission coefficient can be represented as , determined based on the signal ratio between the second microwave signal matched with the microwave signal frequency and the first microwave signal.

[0076] S12, determining the signal-to-noise ratio under the microwave signal frequency based on the difference between the signal transmission characteristic coefficient and the initial transmission coefficient.

[0077] The signal-to-noise ratio under the microwave signal frequency refers to the signal-to-noise ratio obtained by taking the signal transmission characteristic coefficient as the reference. For example, the ratio between the modulus value of the signal transmission characteristic coefficient and the modulus value of the initial transmission coefficient can be determined as the signal-to-noise ratio under the microwave signal frequency.

[0078] For example, The signal transmission characteristic coefficient is represented as The initial transmission coefficient is represented as .

[0079] S13, determining the smaller value between the sampling number matched with the signal-to-noise ratio and the upper limit of the sampling number as the sampling number under the microwave signal frequency.

[0080] For example, the sampling number under the microwave signal frequency satisfies:

[0081]

[0082] Wherein, The sampling number under the microwave signal frequency is represented as The sampling number matched with the signal-to-noise ratio is represented as The upper limit of the sampling number is represented as

[0083] For example, when is set to 1000, if the sampling number matched with the signal-to-noise ratio calculated by the signal-to-noise ratio relationship exceeds 1000 times, the sampling number under the microwave signal frequency is set to 1000 times to avoid leading to uncontrolled measurement time.

[0084] S206, collecting a plurality of candidate transmission coefficients of the resonant cavity under the microwave signal frequency according to the sampling number.

[0085] For example, for each sampling, a signal ratio between the second microwave signal and the first microwave signal obtained by each sampling can be determined as a candidate transmission coefficient, and then a plurality of candidate transmission coefficients matched with the number of samplings can be obtained.

[0086] S208, based on each candidate transmission coefficient, determining a signal transmission coefficient of the resonant cavity corresponding to the microwave signal frequency.

[0087] For example, an average value of each candidate transmission coefficient can be determined as the signal transmission coefficient of the resonant cavity corresponding to the microwave signal frequency.

[0088] S210, based on the signal transmission parameter relationship, fitting the signal transmission coefficients respectively corresponding to each microwave signal frequency, and obtaining the performance parameter of the resonant cavity in the case of fitting error convergence.

[0089] Wherein, the fitting error convergence represents that the fitting error is minimum. The manner of fitting the signal transmission coefficients respectively corresponding to each microwave signal frequency based on the signal transmission parameter relationship, and obtaining the performance parameter of the resonant cavity in the case of fitting error convergence is not limited, and several manners thereof are exemplified below.

[0090] In one of the implementation manners, the signal transmission parameter relationship can be inverted to obtain a signal transmission inverse parameter relationship; based on the signal transmission inverse parameter relationship and the signal transmission parameter relationship, the signal transmission coefficients respectively corresponding to each microwave signal frequency are fitted, and the performance parameter of the resonant cavity is obtained in the case of fitting error convergence.

[0091] For example, the signal transmission parameter relationship satisfies:

[0092]

[0093] Then the signal transmission inverse parameter relationship satisfies:

[0094]

[0095] Based on Figure 2The content shown, by obtaining the signal transmission parameter relationship of the resonant cavity and the signal transmission characteristic coefficient of the resonant cavity at the characteristic frequency, and for each microwave signal frequency to be sampled, based on the difference between the signal transmission characteristic coefficient and the initial transmission coefficient collected for the resonant cavity at the microwave signal frequency, determining the sampling number at the microwave signal frequency, and collecting a plurality of candidate transmission coefficients of the resonant cavity at the microwave signal frequency according to the sampling number, based on each candidate transmission coefficient, determining the corresponding signal transmission coefficient of the resonant cavity at the microwave signal frequency, and then, based on the signal transmission parameter relationship, fitting the signal transmission coefficients corresponding to each microwave signal frequency respectively, and obtaining the performance parameters of the resonant cavity in the case of fitting error convergence. Thus, on the one hand, by adaptively determining the sampling number corresponding to the microwave signal frequency, compared with the unbalanced signal-to-noise ratio caused by the fixed average number of scanning mode, the performance analysis accuracy of the resonant cavity can be improved. On the other hand, by fitting the parameters based on the pre-set signal transmission parameter relationship, the analysis efficiency of the performance parameters of the resonant cavity can be improved.

[0096] In combination Figure 2 The content shown, in some embodiments, a frequency sequence can be set, the first frequency in the frequency sequence is the characteristic frequency, the characteristic frequency refers to the frequency near the resonant frequency of the resonant cavity, and the frequencies in the frequency sequence except the first frequency are the microwave signal frequencies to be sampled. Thus, in the case of obtaining the signal transmission characteristic coefficient corresponding to the characteristic frequency and the signal transmission coefficients corresponding to each microwave signal frequency respectively, by combining the signal transmission characteristic coefficient and the plurality of signal transmission coefficients, the signal transmission coefficient sequence can be obtained.

[0097] Specifically, as Figure 3 The present disclosure provides a flowchart for obtaining a signal transmission coefficient sequence. Taking the processor in the resonant cavity performance parameter determination system as an example, the method includes the following steps:

[0098] S302, for the characteristic frequency in the frequency sequence, obtaining the first microwave signal and the second microwave signal matched with the characteristic frequency obtained by each sampling according to the sampling number corresponding to the characteristic frequency.

[0099] In some embodiments, the sampling number corresponding to the characteristic frequency can be a preset number. For example, the preset number can be 10 times, or other values.

[0100] S304, determining the signal transmission coefficient at the characteristic frequency based on the signal ratio between the second microwave signal and the first microwave signal matched with the characteristic frequency obtained by each sampling.

[0101] S306, determining the signal transmission characteristic coefficient at the characteristic frequency based on the mean value of the plurality of signal transmission coefficients matched with the sampling number corresponding to the characteristic frequency.

[0102] S308, for each to-be-sampled microwave signal frequency in the frequency sequence, obtaining, according to the sampling number corresponding to the microwave signal frequency, the first microwave signal and the second microwave signal matched with the microwave signal frequency obtained by each sampling; the signal ratio between the second microwave signal and the first microwave signal matched with the microwave signal frequency represents the candidate transmission coefficient under the microwave signal frequency.

[0103] S310, determining the signal transmission coefficient under the microwave signal frequency based on the mean value of the multiple candidate transmission coefficients matched with the sampling number corresponding to the microwave signal frequency.

[0104] S312, obtaining the signal transmission coefficient sequence containing the signal transmission characteristic coefficient and the multiple signal transmission coefficients.

[0105] Based on Figure 3 As shown in the content, for the problem of signal-to-noise ratio imbalance caused by the existing scanning mode with fixed average number, by proposing an adaptive dynamic average test method, the signal-to-noise ratio near the resonant frequency of the resonant cavity can be improved while improving the measurement efficiency, and the accuracy of the performance analysis of the resonant cavity can be improved.

[0106] In one embodiment, the performance parameters of the resonant cavity include the resonant frequency, the total quality factor, the internal quality factor and the external quality factor, based on the signal transmission parameter relationship, the signal transmission coefficients corresponding to each microwave signal frequency are fitted, and in the case of fitting error convergence, the performance parameters of the resonant cavity are obtained. The implementation mode includes the following steps:

[0107] S21, obtaining the signal transmission inverse parameter relationship by inverting the signal transmission parameter relationship.

[0108] Among them, the content of the signal transmission parameter relationship and the signal transmission inverse parameter relationship can be described by referring to the content in S210.

[0109] S22, based on the signal transmission parameter relationship, fitting each signal transmission coefficient, and obtaining the resonant frequency and the total quality factor of the resonant cavity in the case of fitting error convergence.

[0110] Among them, the way of fitting each signal transmission coefficient based on the signal transmission parameter relationship and obtaining the resonant frequency and the total quality factor of the resonant cavity in the case of fitting error convergence is not limited, and the following examples are illustrated in combination with possible implementation modes.

[0111] In one implementation, a first phase change parameter relationship matching the signal transmission parameter relationship can be determined; the first phase change parameter relationship is used to represent the relationship between the first signal phase, the total quality factor, the microwave signal frequency and the first resonance frequency; based on the first phase change parameter relationship and the signal transmission parameter relationship, the signal transmission coefficients are fitted to obtain the resonance frequency and the total quality factor of the resonant cavity when the fitting error converges.

[0112] Exemplarily, represents the microwave signal frequency, represents the first signal phase, represents the total quality factor, represents the first resonance power, and the first phase change parameter relationship can satisfy:

[0113]

[0114] S23, based on the signal transmission inverse parameter relationship, the signal transmission inverse coefficient corresponding to each signal transmission coefficient is fitted to obtain the internal quality factor of the resonant cavity when the fitting error converges; the signal transmission inverse coefficient corresponding to any signal transmission coefficient is obtained by inverting the signal transmission coefficient.

[0115] The implementation of obtaining the internal quality factor of the resonant cavity based on the signal transmission inverse parameter relationship is not limited, and possible implementation manners are exemplified below.

[0116] In some embodiments, a preset algorithm can be used to obtain the internal quality factor of the resonant cavity. The preset algorithm includes a first processing relationship of fitting the signal transmission inverse coefficient corresponding to each signal transmission coefficient based on the signal transmission inverse parameter relationship, and a second processing relationship of outputting the corresponding internal quality factor when the fitting error converges.

[0117] S24, performance parameters including the resonance frequency, the total quality factor, the internal quality factor and the external quality factor are obtained; the external quality factor is determined according to the total quality factor and the internal quality factor.

[0118] Exemplarily, the relationship among the external quality factor, the total quality factor and the internal quality factor satisfies:

[0119]

[0120] wherein, represents the external quality factor, represents the internal quality factor of the resonant cavity when the fitting error converges, Total quality factor of the resonant cavity in case of convergence of fitting error.

[0121] Based on the content of S21-S24, the total quality factor is obtained based on the signal transmission parameter relationship, and the internal quality factor is obtained based on the signal transmission inverse parameter relationship, so that through the fitting in two steps, the direct fitting of 7 parameters can be avoided, the size of the fitting parameter space is effectively reduced, and the difficulty of initial value selection is reduced, and the accuracy of performance analysis of the resonant cavity can be improved.

[0122] In some embodiments, based on the signal transmission parameter relationship, each signal transmission coefficient is fitted, and in case of convergence of fitting error, the resonant frequency and the total quality factor (i.e. S22) of the resonant cavity are obtained, including the following steps:

[0123] S221, eliminating the phase accumulation caused by the electrical delay to obtain the signal transmission correction parameter relationship corresponding to the signal transmission parameter relationship, and the signal transmission correction coefficient corresponding to each signal transmission coefficient.

[0124] It should be understood that, since the signals of different frequencies in the data cause different speeds of phase accumulation in the line, therefore, the distribution of the data in the complex space is as shown in (a) of Figure 4 , which presents a spiral distribution. Therefore, by removing the phase accumulation caused by the electrical delay in the data, the data after removing the electrical delay phase accumulation is a standard circular distribution in the complex space as shown in (b) of Figure 4 , therefore, the value of the electrical delay parameter can be optimized based on the gradient descent optimization algorithm.

[0125] For example, for the signal transmission parameter relationship, by setting the electrical delay to 0, the phase accumulation caused by the electrical delay can be eliminated, and the signal transmission correction parameter relationship satisfies:

[0126]

[0127] wherein, represents the signal transmission correction coefficient.

[0128] For example, the signal transmission correction coefficient and the signal transmission coefficient satisfy: , then when the signal transmission coefficient is determined, the signal transmission correction coefficient corresponding to the signal transmission coefficient can be obtained.

[0129] S222, based on the projection positions of each signal transmission correction coefficient in the complex space, the first signal phase corresponding to each microwave signal frequency is determined.

[0130] In some embodiments, a circle fitting process can be performed based on the respective projection positions of the signal transmission correction coefficients in the complex space, to obtain a first fitted circle; the center of the first fitted circle is taken as a new coordinate origin, and the respective first coordinate information of the signal transmission correction coefficients in the complex space is updated; and based on the updated respective first coordinate information, the respective first signal phases corresponding to the respective microwave signal frequencies are determined.

[0131] For example, the first coordinate information of the signal transmission correction coefficients in the complex space includes a coordinate origin. When the coordinate origin of the signal transmission correction coefficients in the complex space is translated to the center of the first fitted circle, the respective first coordinate information of the signal transmission correction coefficients in the complex space can be updated.

[0132] For example, when the initial value in the circle fitting is determined, the circle fitting process based on the respective projection positions of the signal transmission correction coefficients in the complex space can obtain a fitting effect diagram as shown in FIG. 6. Figure 5 When the center of the first fitted circle is taken as a new coordinate origin, and the respective first coordinate information of the signal transmission correction coefficients in the complex space is updated, a coordinate translation result diagram as shown in FIG. 7 can be obtained. Figure 6

[0133] In one embodiment, a circle fitting process can be performed based on the respective projection positions of the signal transmission correction coefficients in the complex space, to obtain a first fitted circle; and based on the respective tangent values of the signal transmission correction coefficients relative to the center of the first fitted circle, the respective first signal phases corresponding to the respective microwave signal frequencies are determined.

[0134] S223, converting the signal transmission correction parameter relationship to obtain a corresponding first phase change parameter relationship; the first phase change parameter relationship is used to represent the relationship between the first signal phase, the total quality factor, the microwave signal frequency and the first resonance frequency.

[0135] For example, the first phase change parameter relationship satisfies:

[0136]

[0137] In the first phase change parameter relationship, denotes the first signal phase, denotes the total quality factor, denotes the first resonance frequency, denotes the microwave signal frequency.

[0138] S224, based on the first phase change parameter relationship, performing phase fitting on the respective first signal phases corresponding to the respective microwave signal frequencies, to obtain the resonance frequency first initial value and the total quality factor initial value of the resonant cavity. ​

[0139] In some embodiments, the modulus information of the signal transmission correction coefficient corresponding to each microwave signal frequency is extracted; the microwave signal frequency corresponding to the minimum modulus information in the modulus information is determined as the initial fitting value of the first resonance frequency in the first phase change parameter relationship.

[0140] For example, represents the signal transmission correction coefficient at the microwave signal frequency f, represents the modulus information of the signal transmission correction coefficient at the microwave signal frequency f, the minimum modulus information can be determined as the initial fitting value of the first resonance frequency corresponding to the microwave signal frequency f. .

[0141] In some embodiments, the frequency bandwidth corresponding to the minimum modulus information decayed by a preset decibel is extracted, and the ratio of the initial fitting value of the first resonance frequency in the first phase change parameter relationship to the frequency bandwidth is determined as the initial fitting value of the total quality factor in the first phase change parameter relationship. The preset decibel can be 3dB or other values.

[0142] For example, taking 3dB as the preset decibel, represents the frequency bandwidth, represents the initial fitting value of the total quality factor, and .

[0143] In some embodiments, the first frequency value and the phase value in the first phase change parameter relationship are extracted, and based on the first frequency value and the phase value, the initial fitting value of the first signal phase in the first phase change parameter relationship is obtained.

[0144] For example, represents the first frequency value in the first phase change parameter relationship, represents the first phase value in the first phase change parameter relationship, and the initial fitting value of the first signal phase in the first phase change parameter relationship satisfies:

[0145]

[0146] Based on the above, the initial fitting values , and corresponding to the first phase change parameter relationship can be determined, and the first phase change parameter relationship takes the corresponding initial fitting values as the initial values. The phase fitting of the first signal phase corresponding to each microwave signal frequency can be performed, and the resonance frequency first initial value, the total quality factor initial value and the first signal phase initial value can be extracted. The schematic diagram of the fitting result can be as follows​Figure 7 as shown.

[0147] S225, based on the signal transmission parameter relationship, fitting each signal transmission coefficient with the resonant frequency first initial value and the total quality factor initial value as initial values, obtaining the resonant frequency and the total quality factor of the resonant cavity in the case of fitting error convergence.

[0148] For example, the resonant frequency first initial value, the total quality factor initial value, the background phase first initial value, the background attenuation amplitude first initial value, the phase first initial value caused by the impedance mismatch of the input port and the output port of the resonant cavity, the first modulus value corresponding to the equivalent external quality factor, and the electric delay first initial value satisfy:

[0149]

[0150] wherein, , and respectively represent the resonant frequency first initial value, the total quality factor initial value and the first signal phase initial value extracted based on the first phase change parameter relationship, represents the electric delay of the resonant cavity based on S31-S33. represents the target value matched with the resonant frequency first initial value, represents the target value matched with the total quality factor initial value, represents the background phase first initial value, represents the background attenuation amplitude first initial value, represents the phase first initial value caused by the impedance mismatch of the input port and the output port of the resonant cavity, represents the first modulus value corresponding to the equivalent external quality factor, represents the electric delay first initial value. is the center of the first fitting circle, represents the radius of the first fitting circle.

[0151] For example, with the target value matched with the resonant frequency first initial value, the target value matched with the total quality factor initial value, the background phase first initial value, the background attenuation amplitude first initial value, the phase first initial value caused by the impedance mismatch of the input port and the output port of the resonant cavity, the first modulus value corresponding to the equivalent external quality factor, and the electric delay first initial value as initial values, based on the signal transmission parameter relationship, fitting each signal transmission coefficient, and when the fitting error is minimized, the corresponding resonant frequency and total quality factor are determined as the resonant frequency and the total quality factor of the resonant cavity obtained in the case of fitting error convergence.

[0152] For example, based on the content of S221-S225, the following can be obtained: Figure 8schematic diagram of the fitting results shown in (a), (b) and (c) in FIG. 8.

[0153] Based on the content of S221-S225, the influence of phase accumulation on the resonant frequency and total quality factor of the resonant cavity can be avoided by eliminating the phase accumulation caused by the electrical delay. Furthermore, based on the signal transmission correction parameter relationship obtained after eliminating the phase accumulation caused by the electrical delay, and based on the first phase change parameter relationship corresponding to the signal transmission correction parameter relationship, the resonant frequency and total quality factor of the resonant cavity can be determined, which can improve the accuracy of the obtained resonant frequency and total quality factor.

[0154] In some embodiments, the process of obtaining the signal transmission correction coefficient corresponding to each signal transmission coefficient respectively includes:

[0155] S31, based on the respective projection positions of each signal transmission correction coefficient in the complex space, an original curve is obtained.

[0156] For example, the original curve is obtained by combining the respective projection positions of each signal transmission correction coefficient in the complex space.

[0157] S32, a plurality of feature points in the original curve whose data interval between the curve end portions satisfies the interval condition are selected, and the phase corresponding to each feature point is linearly fitted to obtain an electrical delay initial value.

[0158] In some embodiments, the curve end portions include the curve starting point and the curve ending point of the original curve, and the plurality of feature points in the original curve whose data interval between the curve end portions satisfies the interval condition are selected, including: if the distance between the data point in the original curve and the curve starting point is within a first preset range, the data point in the original curve is determined as a feature point; or, if the distance between the data point in the original curve and the curve ending point is within a second preset range, the data point in the original curve is determined as a feature point. For example, the first 10% of data points in the original curve can be selected as feature points, or the last 10% of data points in the original curve can be selected as feature points.

[0159] It should be understood that since the phase change of the data points at both ends of the original curve is most affected by the electrical delay, the accuracy can be improved when selecting a plurality of feature points based on the end portions of the original curve.

[0160] In some embodiments, the phase corresponding to each feature point can be linearly fitted to obtain a fitting slope, and the product of the fitting slope and a preset value is determined as the electrical delay initial value. For example, the preset value can be .

[0161] S33, based on the projection positions of the signal transmission coefficients respectively, performing circle fitting by taking the electric delay initial value as a fitting initial value and taking the standard deviation of the distances between the feature points and the center of the first fitting circle as a fitting loss, and obtaining the electric delay of the resonant cavity in a case where the fitting loss converges.

[0162] Exemplarily, the circle fitting processing can be performed based on the projection positions of the signal transmission correction coefficients respectively in the complex space to obtain the first fitting circle.

[0163] The fitting loss convergence indicates that the fitting loss is minimum. Exemplarily, the electric delay corresponding to the minimum fitting loss can be determined as the electric delay of the resonant cavity based on the gradient descent method.

[0164] S34, for each signal transmission coefficient, canceling the phase accumulation caused by the electric delay based on the signal transmission coefficient to obtain a signal transmission correction coefficient corresponding to the signal transmission coefficient.

[0165] Based on the contents of S31-S34, by obtaining the original curve based on the projection positions of the signal transmission correction coefficients respectively in the complex space, and then independently extracting the electric delay parameter by considering the standard deviation of the distances between the two end data of the original curve and the center of the first fitting circle, the fitting accuracy of the electric delay parameter can be improved by removing the phase accumulation caused by the electric delay.

[0166] In combination with the contents of S31-S34, as shown in Figure 9 The present disclosure provides a schematic diagram of obtaining the electric delay of the resonant cavity. Taking a processor applied in a resonant cavity performance parameter determination system as an example, the method comprises the following steps:

[0167] S902, based on the projection positions of the signal transmission correction coefficients respectively in the complex space, obtaining an original curve.

[0168] S904, selecting the data points in the front 10% or the data points in the back 10% from the original curve as a plurality of feature points.

[0169] S906, performing linear fitting on the phases corresponding to the feature points respectively to obtain a fitting slope, and determining the product of the fitting slope and a preset value as an electric delay initial value.

[0170] S908, based on the projection positions of the signal transmission coefficients respectively, performing circle fitting by taking the electric delay initial value as a fitting initial value and taking the standard deviation of the distances between the feature points and the center of the first fitting circle as a fitting loss, and obtaining the electric delay of the resonant cavity in a case where the fitting loss converges;

[0171] S910, for each signal transmission coefficient, canceling phase accumulation caused by electrical delay on the basis of the signal transmission coefficient to obtain a signal transmission correction coefficient corresponding to the signal transmission coefficient.

[0172] Exemplarily, the signal transmission correction coefficient and the signal transmission coefficient satisfy: Therefore, when the signal transmission coefficient is known, the signal transmission correction coefficient corresponding to the signal transmission coefficient can be obtained.

[0173] Based on the content of S902-S910, by obtaining the original curve based on the respective projection positions of the signal transmission correction coefficients in the complex space, and then independently extracting the electrical delay parameter by considering the standard deviation of the distance between the two end data of the original curve relative to the center of the first fitting circle, the fitting accuracy of the electrical delay parameter can be improved by removing the phase accumulation caused by the electrical delay.

[0174] In combination with the above content, in one embodiment, based on the signal transmission inverse parameter relationship, the signal transmission inverse coefficient corresponding to each signal transmission coefficient is fitted, and in the case of fitting error convergence, the implementation of the internal quality factor (i.e., S23) of the resonant cavity is obtained, including the following steps:

[0175] S231, eliminating the phase accumulation caused by the electrical delay to obtain the signal transmission inverse correction parameter relationship corresponding to the signal transmission inverse parameter relationship, and the signal transmission inverse correction coefficient corresponding to each signal transmission inverse coefficient.

[0176] Exemplarily, for the signal transmission inverse parameter relationship, by setting the electrical delay to 0, the phase accumulation caused by the electrical delay can be eliminated, and the signal transmission inverse correction parameter relationship corresponding to the signal transmission inverse parameter relationship can be obtained.

[0177] Exemplarily, The signal transmission inverse correction coefficient is represented by The signal transmission inverse coefficient is represented by .

[0178] As can be known from the content of S231, in the case of obtaining the signal transmission coefficient corresponding to the signal transmission inverse coefficient, based on the relationship between the signal transmission inverse coefficient and the signal transmission inverse correction coefficient: The signal transmission inverse correction coefficient corresponding to each signal transmission inverse coefficient can be obtained.

[0179] In some embodiments, S231 can be replaced by the following steps: eliminating phase accumulation caused by electrical delay, obtaining signal transmission inverse correction parameter relationship corresponding to signal transmission inverse parameter relationship, and signal transmission correction coefficient corresponding to each signal transmission coefficient respectively; inverting each signal transmission correction coefficient to obtain each signal transmission inverse correction coefficient. That is, by eliminating phase accumulation caused by electrical delay, signal transmission inverse correction coefficient corresponding to each signal transmission coefficient can be obtained. corresponding signal transmission correction coefficient , by inverting , signal transmission inverse correction coefficient can be obtained .

[0180] S232, based on the projection position of each signal transmission inverse correction coefficient in the complex space, circular fitting processing is performed to obtain a second fitting circle.

[0181] For example, based on the content of S232, a fitting result diagram as shown in Figure 10 can be obtained.

[0182] S233, taking the center of the second fitting circle as a new coordinate origin, updating the second coordinate information of each signal transmission inverse correction coefficient in the complex space.

[0183] For example, based on the content of S233, a fitting result diagram as shown in Figure 11 can be obtained.

[0184] S234, based on the updated second coordinate information, determining the second signal phase corresponding to each microwave signal frequency.

[0185] S235, converting the signal transmission inverse correction parameter relationship to obtain the corresponding second phase change parameter relationship; the second phase change parameter relationship is used to represent the relationship between the second signal phase, the internal quality factor, the microwave signal frequency and the second resonance frequency.

[0186] For example, the second phase change parameter relationship satisfies:

[0187]

[0188] In the second phase change parameter relationship, represents the second signal phase, represents the internal quality factor, represents the microwave signal frequency, represents the second resonance frequency.

[0189] S236, based on the second phase change parameter relationship, performing phase fitting on the second signal phase corresponding to each microwave signal frequency to obtain the resonance frequency second initial value and the internal quality factor initial value of the resonant cavity.

[0190] wherein, for the variables involved in the second phase variation parameter relationship 、 and the corresponding initial fitting values can be determined in the following manner.

[0191] For example, the initial fitting value of the resonant frequency in the second phase variation parameter relationship is the same as the resonant frequency of the resonant cavity obtained in the case of fitting error convergence.

[0192] For example, the initial fitting value of the internal quality factor in the second phase variation parameter relationship satisfies:

[0193]

[0194] wherein, represents the radius of the second fitting circle, represents the first modulus value of the equivalent external quality factor obtained in the case of fitting error convergence, is the first initial value of the background attenuation amplitude obtained in the case of fitting error convergence, i.e., the fitting result of S225 in the case of fitting error convergence includes and .

[0195] For example, the first frequency value and the phase value in the second phase variation parameter relationship are extracted; based on the first frequency value and the phase value, the initial fitting value of the second signal phase in the second phase variation parameter relationship is obtained.

[0196] For example, represents the first frequency value in the second phase variation parameter relationship, represents the first phase value in the second phase variation parameter relationship, represents the initial fitting value of the second resonant frequency in the second phase variation parameter relationship, then the initial fitting value of the second signal phase in the second phase variation parameter relationship satisfies:

[0197]

[0198] Therefore, based on the above, the initial fitting values 、 and corresponding to the second phase variation parameter relationship can be determined, and then the second signal phase corresponding to each microwave signal frequency is phase-fitted with the corresponding initial fitting value as the initial value, the second initial value of the resonant frequency of the resonant cavity, the initial value of the internal quality factor, and the initial value of the second signal phase can be obtained, and the fitting result can be as followsFigure 12 as shown.

[0199] S237, based on the signal transmission inverse parameter relationship, fitting each signal transmission inverse coefficient with the resonant frequency second initial value and the internal quality factor initial value as initial values, obtaining the internal quality factor of the resonant cavity in the case of fitting error convergence.

[0200] Exemplarily, the resonant frequency second initial value, the internal quality factor initial value, the background phase second initial value, the background attenuation amplitude second initial value, the phase second initial value generated due to the impedance mismatch of the input port and the output port of the resonant cavity, the second modulus corresponding to the equivalent external quality factor, and the electrical delay second initial value satisfy:

[0201]

[0202] wherein, , and respectively represent the resonant frequency second initial value, the internal quality factor initial value, and the second signal phase initial value extracted based on the second phase change parameter relationship. represents a target value matched with the resonant frequency second initial value, represents a target value matched with the internal quality factor initial value, represents the background phase second initial value, represents the background attenuation amplitude second initial value, represents the phase second initial value generated due to the impedance mismatch of the input port and the output port of the resonant cavity, represents the second modulus corresponding to the equivalent external quality factor, represents the electrical delay second initial value. represents the center of the second fitting circle, represents the radius of the second fitting circle.

[0203] Exemplarily, with the target value matched with the resonant frequency second initial value, the target value matched with the internal quality factor initial value, the background phase second initial value, the background attenuation amplitude second initial value, the phase second initial value generated due to the impedance mismatch of the input port and the output port of the resonant cavity, the second modulus corresponding to the equivalent external quality factor, and the electrical delay second initial value as initial values, based on the signal transmission inverse parameter relationship, fitting each signal transmission inverse coefficient, and determining the corresponding internal quality factor as the internal quality factor of the resonant cavity in the case of fitting error convergence when the fitting error is minimized.

[0204] Specifically, the initial value of the target value matched with the resonant frequency second initial value, the initial value of the target value matched with the internal quality factor initial value, the background phase second initial value, the background amplitude second initial value, the phase second initial value caused by the impedance mismatch of the resonant cavity input and output port, the second modulus corresponding to the equivalent external quality factor, and the second initial value of the electrical delay can be used to fit the signal transmission inverse parameter relationship, and the internal quality factor of the resonant cavity can be obtained. The signal transmission inverse parameter relationship satisfies:

[0205]

[0206] The contents of S231-S237 can be adapted to the contents of S221-S225, such as the fitting results shown in Figure 13 based on the contents of S231-S237.

[0207] Based on the contents of S231-S237, the influence of phase accumulation on the internal quality factor of the resonant cavity can be reduced by eliminating the phase accumulation caused by the electrical delay, and then the accuracy of the obtained internal quality factor can be improved when the internal quality factor of the resonant cavity is determined based on the signal transmission inverse correction parameter relationship obtained after eliminating the phase accumulation caused by the electrical delay and the second phase change parameter relationship corresponding to the signal transmission inverse correction parameter relationship, thereby improving the accuracy of the performance analysis of the resonant cavity.

[0208] In combination with the above contents, as shown in Figure 14 The present disclosure provides a flowchart of a resonant cavity performance parameter determination method, which is applied to a processor in a resonant cavity performance parameter determination system, including the following steps:

[0209] S1402, eliminating the phase accumulation caused by the electrical delay to obtain a signal transmission correction parameter relationship corresponding to a signal transmission parameter relationship.

[0210] Among them, the resonant frequency and the total quality factor of the resonant cavity can be obtained in the case of fitting error convergence based on S1404-S1414. The internal quality factor of the resonant cavity can be obtained in the case of fitting error convergence based on S1416-S1426.

[0211] S1404, based on the respective projection positions of the signal transmission correction coefficients corresponding to the respective signal transmission coefficients in the complex space, performing circular fitting processing to obtain a first fitting circle.

[0212] S1406, taking the center of the first fitting circle as a new coordinate origin, and updating the respective first coordinate information of the signal transmission correction coefficients in the complex space.

[0213] S1408, determine the first signal phase corresponding to each microwave signal frequency based on the updated first coordinate information of each signal transmission inverse correction coefficient.

[0214] S1410, convert the signal transmission correction parameter relationship to obtain the corresponding first phase change parameter relationship.

[0215] S1412, based on the first phase change parameter relationship, phase fitting is performed on the first signal phase corresponding to each microwave signal frequency to obtain the first initial value of the resonance frequency and the initial value of the total quality factor of the resonant cavity.

[0216] S1414, taking the first initial value of the resonance frequency and the initial value of the total quality factor as the initial value, based on the signal transmission parameter relationship, fitting is performed on each signal transmission coefficient, and the resonance frequency and the total quality factor of the resonant cavity are obtained under the condition that the fitting error converges.

[0217] S1416, based on the projection position of each signal transmission inverse correction coefficient in the complex space, a second fitting circle is obtained by circular fitting processing.

[0218] Among them, the signal transmission inverse coefficient corresponding to any signal transmission coefficient is obtained by inverting the signal transmission coefficient.

[0219] S1418, taking the center of the second fitting circle as a new coordinate origin, updating the second coordinate information of each signal transmission inverse correction coefficient in the complex space.

[0220] S1420, determine the second signal phase corresponding to each microwave signal frequency based on the updated second coordinate information of each signal transmission inverse correction coefficient.

[0221] S1422, convert the signal transmission inverse correction parameter relationship to obtain the corresponding second phase change parameter relationship.

[0222] S1424, based on the second phase change parameter relationship, phase fitting is performed on the second signal phase corresponding to each microwave signal frequency to obtain the second initial value of the resonance frequency and the initial value of the internal quality factor of the resonant cavity.

[0223] S1426, taking the second initial value of the resonance frequency and the initial value of the internal quality factor as the initial value, based on the signal transmission inverse parameter relationship corresponding to the signal transmission parameter relationship, fitting is performed on each signal transmission inverse coefficient, and the internal quality factor of the resonant cavity is obtained under the condition that the fitting error converges.

[0224] S1428, based on the total quality factor and the internal quality factor of the resonant cavity, the external quality factor of the resonant cavity is obtained.

[0225] The content of S1402-S1428 can be referred to the foregoing adaptive description, and will not be described here again.

[0226] In the foregoing embodiments, except for the steps of removing the fitting electrical delay (corresponding to S1402) and determining the external quality factor (corresponding to S1428), the remaining steps are divided into two branches. The difference between the two branches is that the first branch (corresponding to S1404 to S1414) fits the signal transmission correction coefficient (S 21,de data) to obtain the total quality factor ; and the second branch (corresponding to S1416 to S1426) fits the inverse data of the signal transmission inverse correction coefficient (S 21,de to obtain the internal quality factor .

[0227] The present disclosure can use an adaptive dynamic average method to test the change of the signal with frequency , and then fit and in steps. This method can achieve approximately consistent signal-to-noise ratio (SNR) in the entire measurement frequency band by performing dynamic average measurement at different frequencies, and can avoid directly fitting 7 parameters by fitting in steps, with at most 3 parameters fitted in each step, effectively reducing the size of the fitting parameter space and the difficulty of initial value selection. Meanwhile, the fitting of the signal can obtain accurate value when and differ greatly. When the fitting error is large, this step-by-step fitting method is beneficial for troubleshooting, and thus can solve the problem faster.

[0228] In summary, the method provided by the present disclosure can adaptively adjust the sampling number of each frequency point according to the modulus of the signal transmission coefficient at the frequency of the microwave signal to be sampled, to maintain the relative consistency of the signal-to-noise ratio (SNR) at each frequency point. By splitting the process of fitting the signal into processes such as calibrating the electrical delay, circle fitting, and phase fitting, the parameter space of each fitting step can be reduced, and the fitting efficiency and success rate can be improved. By fitting the signal in steps to determine , and combining determined by the signal to calculate .

[0229] Moreover, after the phase accumulation caused by the electrical delay is removed by optimization, the The standard deviation of the distance between the two ends of the data relative to the center of the circle is used to extract the electrical delay, which can improve the fitting accuracy of the electrical delay of the resonant cavity.

[0230] In some embodiments, as shown in FIG. 1, Figure 15 The present disclosure provides a resonant cavity performance parameter determination system for measuring a quantum bit. The resonant cavity performance parameter determination system 150 includes a processor 1502, a microwave collector 1504, and a microwave generator 1506, wherein the processor 1502 is connected to the microwave collector 1504 and the microwave generator 1506.

[0231] Specifically, the microwave generator 1506 is configured to input a first microwave signal into the resonant cavity 160; the microwave collector 1504 is configured to receive a second microwave signal output by the resonant cavity; and the signal ratio between the second microwave signal and the first microwave signal is used to represent the transmission coefficient of the resonant cavity. The processor 1502 is configured to obtain a signal transmission parameter relationship of the resonant cavity and a signal transmission characteristic coefficient of the resonant cavity at a characteristic frequency; the signal transmission parameter relationship is used to represent the relationship between the signal transmission coefficient of the resonant cavity and the microwave signal frequency and the performance parameter of the resonant cavity; for each microwave signal frequency to be sampled, the sampling number at the microwave signal frequency is determined based on the difference between the signal transmission characteristic coefficient and the initial transmission coefficient collected for the resonant cavity at the microwave signal frequency; a plurality of candidate transmission coefficients of the resonant cavity at the microwave signal frequency are collected according to the sampling number; the statistical value of each candidate transmission coefficient is determined as the corresponding signal transmission coefficient of the resonant cavity at the microwave signal frequency; and the performance parameter of the resonant cavity is obtained by fitting the respective signal transmission coefficients at each microwave signal frequency based on the signal transmission parameter relationship under the condition that the fitting error converges.

[0232] The specific steps processed by the processor 1502 can be adapted to the foregoing description and will not be described here.

[0233] The transmission coefficient can include the signal transmission characteristic coefficient of the resonant cavity at the characteristic frequency, each candidate transmission coefficient of the resonant cavity at the microwave signal frequency, and the corresponding signal transmission coefficient of the resonant cavity at the microwave signal frequency.

[0234] For example, based on the microwave signal frequency, the processor can control the microwave generator to input the first microwave signal into the resonant cavity and obtain the second microwave signal output by the resonant cavity and received by the microwave collector, and then determine the signal transmission coefficient of the resonant cavity based on the signal ratio between the second microwave signal matching the microwave signal frequency and the first microwave signal. The first microwave signal is the aforementioned , the second microwave signal is the aforementioned , and the signal transmission coefficient is the aforementioned .

[0235] In some embodiments, the resonant cavity performance parameter determination system 20 can further include a memory storing at least one instruction executable by the processor, each instruction for the processor to obtain the performance parameter of the resonant cavity.

[0236] It should be understood that, although each step in the flowchart involved in each of the above-described embodiments is shown in sequence according to the arrow, these steps are not necessarily executed in sequence according to the arrow. Unless otherwise specified herein, the execution of these steps is not strictly limited in sequence, and these steps can be executed in other sequences. Moreover, at least part of the steps in the flowchart involved in each of the above-described embodiments can include multiple steps or stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence of these steps or stages is not necessarily sequential, but can be executed alternately or alternately with at least part of other steps or stages.

[0237] Based on the same inventive concept, the embodiments of the present disclosure also provide a resonant cavity performance parameter determination apparatus for implementing the above-mentioned resonant cavity performance parameter determination method. The implementation scheme for solving the problem provided by the apparatus is similar to the implementation scheme described in the above-mentioned method, and therefore the specific limitations in one or more resonant cavity performance parameter determination apparatus embodiments provided below can refer to the limitations of the resonant cavity performance parameter determination method described above, which will not be described here again.

[0238] In some embodiments, as shown in FIG. 16, Figure 16 As shown in FIG. 16, the present disclosure provides a resonant cavity performance parameter determination apparatus for measuring a quantum bit, which comprises: an acquisition module 1602, configured to acquire a signal transmission parameter relationship of a resonant cavity and a signal transmission characteristic coefficient of the resonant cavity at a characteristic frequency; the signal transmission parameter relationship is used to characterize the relationship between the signal transmission coefficient of the resonant cavity and the microwave signal frequency and the performance parameter of the resonant cavity; a determination module 1604, configured to, for each microwave signal frequency to be sampled, determine the sampling number at the microwave signal frequency based on the difference between the signal transmission characteristic coefficient and the initial transmission coefficient collected for the resonant cavity at the microwave signal frequency; an acquisition module 1606, configured to collect a plurality of candidate transmission coefficients of the resonant cavity at the microwave signal frequency according to the sampling number; an analysis module 1608, configured to determine the corresponding signal transmission coefficient of the resonant cavity at the microwave signal frequency based on each candidate transmission coefficient; and a processing module 1610, configured to fit the corresponding signal transmission coefficient at each microwave signal frequency based on the signal transmission parameter relationship, and obtain the performance parameter of the resonant cavity in the case of fitting error convergence.

[0239] In some embodiments, the determining module 1604 is further configured to: acquire an initial transmission coefficient collected for the resonant cavity at the microwave signal frequency, and a configured upper limit of the number of samples; determine a signal-to-noise ratio at the microwave signal frequency based on a difference between the signal transmission characteristic coefficient and the initial transmission coefficient; and determine the number of samples at the microwave signal frequency as a smaller value between the signal-to-noise ratio matched number of samples and the upper limit of the number of samples.

[0240] In some embodiments, the performance parameters include a resonance frequency, a total quality factor, an internal quality factor, and an external quality factor; and the processing module 1610 is further configured to: obtain a signal transmission inverse parameter relationship by inverting the signal transmission parameter relationship; fit each signal transmission coefficient based on the signal transmission parameter relationship, and obtain the resonance frequency and the total quality factor of the resonant cavity in a case where a fitting error converges; fit each signal transmission inverse coefficient corresponding to each signal transmission coefficient based on the signal transmission inverse parameter relationship, and obtain the internal quality factor of the resonant cavity in a case where a fitting error converges; the signal transmission inverse coefficient corresponding to any signal transmission coefficient is obtained by inverting the signal transmission coefficient; and obtain the performance parameters including the resonance frequency, the total quality factor, the internal quality factor, and the external quality factor; the external quality factor is determined according to the total quality factor and the internal quality factor.

[0241] In some embodiments, the processing module 1610 is further configured to: eliminate phase accumulation caused by electrical delay to obtain a signal transmission correction parameter relationship corresponding to the signal transmission parameter relationship, and signal transmission correction coefficients respectively corresponding to each signal transmission coefficient; determine a first signal phase respectively corresponding to each microwave signal frequency based on a respective projection position of each signal transmission correction coefficient in a complex space; convert the signal transmission correction parameter relationship to obtain a corresponding first phase change parameter relationship; the first phase change parameter relationship is used to represent a relationship among the first signal phase, the total quality factor, the microwave signal frequency, and the first resonance frequency; perform phase fitting on the first signal phase respectively corresponding to each microwave signal frequency based on the first phase change parameter relationship to obtain a first initial value of the resonance frequency and an initial value of the total quality factor of the resonant cavity; and fit each signal transmission coefficient based on the signal transmission parameter relationship with the first initial value of the resonance frequency and the initial value of the total quality factor as initial values, and obtain the resonance frequency and the total quality factor of the resonant cavity in a case where a fitting error converges.

[0242] In some embodiments, the processing module 1610 is further configured to: obtain an original curve based on the respective projection positions of the signal transmission correction coefficients in the complex space; select a plurality of feature points in the original curve that satisfy an interval condition with respect to the data interval between the ends; perform linear fitting on the respective phases corresponding to the feature points to obtain an initial value of the electrical delay; perform circle fitting based on the respective projection positions of the signal transmission coefficients, taking the initial value of the electrical delay as the initial value of fitting and the standard deviation of the distance between the feature points and the center of the first fitting circle as the fitting loss, and obtain the electrical delay of the resonant cavity in the case of convergence of the fitting loss; and for each signal transmission coefficient, offset the phase accumulation caused by the electrical delay based on the signal transmission coefficient to obtain a signal transmission correction coefficient corresponding to the signal transmission coefficient.

[0243] In some embodiments, the processing module 1610 is further configured to: perform circle fitting processing based on the respective projection positions of the signal transmission correction coefficients in the complex space to obtain a first fitting circle; update the respective first coordinate information of the signal transmission correction coefficients in the complex space by taking the center of the first fitting circle as a new coordinate origin; and determine the first signal phases corresponding to the respective microwave signal frequencies based on the updated first coordinate information.

[0244] Each of the modules in the above resonant cavity performance parameter determination apparatus can be realized wholly or partially by software, hardware, or a combination thereof. Each of the modules can be embedded in or independent of a processor in a resonant cavity performance parameter determination system in hardware form, or can be stored in a memory in the resonant cavity performance parameter determination system in software form, so as to be called and executed by the processor to perform the operations corresponding to each of the modules.

[0245] In some embodiments, the present disclosure provides a computer device, which can be a server, and the internal structure diagram thereof can be as shown in Figure 17 The computer device includes a processor, a memory, an input / output interface (I / O), and a communication interface. The processor, the memory, and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. The processor of the computer device is configured to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program, and a database. The internal memory provides an environment for the operating system and the computer program in the non-volatile storage medium to run. The database of the computer device is configured to store data involved in the above resonant cavity performance parameter determination process. The input / output interface of the computer device is configured to exchange information between the processor and external devices. The communication interface of the computer device is configured to communicate with external terminals through a network connection. The computer program is executed by the processor to implement a resonant cavity performance parameter determination method.

[0246] Those skilled in the art can understand that, Figure 17 The structure shown in the figure is only a block diagram of part of the structure related to the scheme of the present disclosure, and does not constitute a limitation on the computer device to which the scheme of the present disclosure is applied. The specific computer device can include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0247] In some embodiments, the present disclosure provides a computer device including a memory and a processor, the memory storing a computer program, and the processor implementing the steps of the above method embodiments when executing the computer program.

[0248] In some embodiments, the present disclosure provides a computer readable storage medium having a computer program stored thereon, the computer program being executed by a processor to implement the steps of the above method embodiments.

[0249] In some embodiments, the present disclosure provides a computer program product including a computer program, the computer program being executed by a processor to implement the steps of the above method embodiments.

[0250] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in the present disclosure are all information and data authorized by the user or authorized by all parties, and the collection, use and processing of related data need to comply with relevant laws, regulations and standards of relevant regions. And the object can choose not to authorize the object information and related data, can refuse or can conveniently refuse to push information, etc.

[0251] In the present disclosure, in the process of collecting and processing related data in actual application, the informed consent or separate consent of the personal information subject should be strictly obtained according to the requirements of the relevant regional laws and regulations, and the subsequent data use and processing behavior should be carried out within the scope of authorization of laws and regulations and personal information subjects.

[0252] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer readable storage medium, and when the computer program is executed, the processes of the above-mentioned embodiments of the methods can be included. Any reference to memory, database or other medium used in the embodiments provided by the present disclosure can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical storage, high-density embedded non-volatile memory, resistive memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration but not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc. The database involved in the embodiments provided by the present disclosure can include at least one of a relational database and a non-relational database. The non-relational database can include a distributed database based on a block chain, etc., without being limited thereto. The processor involved in the embodiments provided by the present disclosure can be a general-purpose processor, a central processing unit, a graphics processing unit, a digital signal processor, a programmable logic device, etc., without being limited thereto.

[0253] Any combination of the technical features of the above embodiments can be made. In order to make the description simple, all possible combinations of the technical features in the above embodiments are not described, however, as long as the combination of the technical features does not exist, it should be considered as the scope of the present disclosure.

[0254] The above embodiments only express several implementation manners of the present disclosure, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent of the present disclosure. It should be noted that for ordinary skilled persons in the art, without departing from the concept of the present disclosure, a number of modifications and improvements can be made, which are within the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be subject to the appended claims.

Claims

1. A method for determining the performance parameters of a resonant cavity, wherein the resonant cavity is used to measure qubits, characterized in that, The method includes: The signal transmission parameter relationship of the resonant cavity and the signal transmission characteristic coefficient of the resonant cavity at the characteristic frequency are obtained, wherein the signal transmission parameter relationship is used to characterize the relationship between the signal transmission coefficient of the resonant cavity and the microwave signal frequency and performance parameters of the resonant cavity. For each microwave signal frequency to be sampled, the number of sampling times at the microwave signal frequency is determined based on the difference between the signal transmission characteristic coefficient and the initial transmission coefficient acquired for the resonant cavity at the microwave signal frequency. According to the number of samplings, multiple candidate transmission coefficients of the resonant cavity at the frequency of the microwave signal are collected; Based on each of the candidate transmission coefficients, the signal transmission coefficient of the resonant cavity at the microwave signal frequency is determined; Based on the relationship of the signal transmission parameters, the signal transmission coefficients corresponding to each of the microwave signal frequencies are fitted, and the performance parameters of the resonant cavity are obtained when the fitting error converges.

2. The method according to claim 1, characterized in that, The step of determining the number of samplings at the microwave signal frequency based on the difference between the signal transmission characteristic coefficients and the initial transmission coefficients acquired for the resonant cavity at the microwave signal frequency includes: Obtain the initial transmission coefficients acquired for the resonant cavity at the microwave signal frequency, as well as the configured upper limit of the number of samplings; The signal-to-noise ratio at the microwave signal frequency is determined based on the difference between the signal transmission characteristic coefficients and the initial transmission coefficients. The smaller value between the number of samplings for signal-to-noise ratio matching and the upper limit of the number of samplings is determined as the number of samplings at the microwave signal frequency.

3. The method according to claim 1, characterized in that, The performance parameters include resonant frequency, total quality factor, internal quality factor, and external quality factor. The process of fitting the signal transmission coefficients corresponding to each of the microwave signal frequencies based on the signal transmission parameter relationships, and obtaining the performance parameters of the resonant cavity when the fitting error converges, includes: Inverse the relationship of the signal transmission parameters to obtain the inverse relationship of the signal transmission parameters; Based on the relationship between the signal transmission parameters, each of the signal transmission coefficients is fitted, and the resonant frequency and total quality factor of the resonant cavity are obtained when the fitting error converges. Based on the inverse signal transmission parameter relationship, the inverse signal transmission coefficient corresponding to each of the signal transmission coefficients is fitted, and the internal quality factor of the resonant cavity is obtained when the fitting error converges; the inverse signal transmission coefficient corresponding to any of the signal transmission coefficients is obtained by inverting the signal transmission coefficient. The performance parameters, including the resonant frequency, the total quality factor, the internal quality factor, and the external quality factor, are obtained; the external quality factor is determined based on the total quality factor and the internal quality factor.

4. The method according to claim 3, characterized in that, The process of fitting each signal transmission coefficient based on the signal transmission parameter relationship, and obtaining the resonant frequency and overall quality factor of the resonant cavity when the fitting error converges, includes: Eliminate phase accumulation caused by electrical delay to obtain the signal transmission correction parameter relationship corresponding to the signal transmission parameter relationship, and the signal transmission correction coefficient corresponding to each of the signal transmission coefficients; Based on the projection positions of each of the signal transmission correction coefficients in the complex space, the first signal phase corresponding to each of the microwave signal frequencies is determined. The signal transmission correction parameter relationship is transformed to obtain the corresponding first phase change parameter relationship; the first phase change parameter relationship is used to characterize the relationship between the first signal phase and the total quality factor, the microwave signal frequency and the first resonant frequency; Based on the first phase change parameter relationship, phase fitting is performed on the first signal phase corresponding to each microwave signal frequency to obtain the first initial value of the resonant frequency and the initial value of the total quality factor of the resonant cavity. Using the initial values ​​of the resonant frequency and the total quality factor as initial values, and based on the relationship between the signal transmission parameters, the signal transmission coefficients are fitted, and the resonant frequency and total quality factor of the resonant cavity are obtained when the fitting error converges.

5. The method according to claim 4, characterized in that, The process of obtaining the signal transmission correction coefficients corresponding to each of the aforementioned signal transmission coefficients includes: The original curve is obtained based on the projection position of each of the signal transmission correction coefficients in the complex space; Multiple feature points in the original curve whose data intervals between the ends satisfy the interval conditions are selected, and the phases corresponding to each feature point are linearly fitted to obtain the initial electrical delay value. The initial electrical delay value is used as the initial fitting value, and the standard deviation of the distance between each feature point and the center of the first fitting circle is used as the fitting loss. Circle fitting is performed based on the projection position of each signal transmission coefficient. When the fitting loss converges, the electrical delay of the resonant cavity is obtained. For each of the signal transmission coefficients, the phase accumulation caused by the electrical delay is offset based on the signal transmission coefficient to obtain the signal transmission correction coefficient corresponding to the signal transmission coefficient.

6. The method according to claim 4, characterized in that, The step of determining the first signal phase corresponding to each microwave signal frequency based on the projection position of each signal transmission correction coefficient in complex space includes: Based on the projection positions of each of the signal transmission correction coefficients in the complex space, a circle fitting process is performed to obtain a first fitted circle; Using the center of the first fitted circle as the new origin, update the first coordinate information of each of the signal transmission correction coefficients in the complex space. Based on the updated first coordinate information, the first signal phase corresponding to each microwave signal frequency is determined.

7. A system for determining the performance parameters of a resonant cavity, wherein the resonant cavity is used to measure qubits, characterized in that, The system includes a processor, a microwave generator, and a microwave acquisition unit; the processor is connected to the microwave generator and the microwave acquisition unit. The microwave generator is used to input a first microwave signal into the resonant cavity; The microwave acquisition device is used to receive the second microwave signal output by the resonant cavity; The signal ratio between the second microwave signal and the first microwave signal is used to characterize the transmission coefficient of the resonant cavity; The processor is used to implement the method as described in any one of claims 1 to 6.

8. A device for determining the performance parameters of a resonant cavity, wherein the resonant cavity is used to measure qubits, characterized in that, The device includes: The acquisition module is used to acquire the signal transmission parameter relationship of the resonant cavity and the signal transmission characteristic coefficient of the resonant cavity at the characteristic frequency; the signal transmission parameter relationship is used to characterize the relationship between the signal transmission coefficient of the resonant cavity and the microwave signal frequency and performance parameters of the resonant cavity. The determination module is used to determine the number of sampling times at each microwave signal frequency based on the difference between the signal transmission characteristic coefficient and the initial transmission coefficient acquired by the resonant cavity at the microwave signal frequency; The acquisition module is used to acquire multiple candidate transmission coefficients of the resonant cavity at the microwave signal frequency according to the number of samplings. The analysis module is used to determine the signal transmission coefficient of the resonant cavity at the microwave signal frequency based on each of the candidate transmission coefficients. The processing module is used to fit the signal transmission coefficients corresponding to each of the microwave signal frequencies based on the signal transmission parameter relationships, and obtain the performance parameters of the resonant cavity when the fitting error converges.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 6.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.

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