Methods, apparatus and systems for determining resonant cavity performance parameters, and computer equipment

Abstract

This disclosure relates to a method, apparatus, system, and computer device for determining the performance parameters of a resonant cavity. The method includes: acquiring the signal transmission parameter relationship of the resonant cavity and the signal transmission characteristic coefficients of the resonant cavity at characteristic frequencies; for each microwave signal frequency to be sampled, determining the number of sampling times 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; acquiring multiple candidate transmission coefficients of the resonant cavity at the microwave signal frequency according to the number of sampling times; determining the corresponding signal transmission coefficient of the resonant cavity at the microwave signal frequency based on each candidate transmission coefficient; fitting the signal transmission coefficients corresponding to each microwave signal frequency based on the signal transmission parameter relationship, and obtaining the performance parameters of the resonant cavity when the fitting error converges. This method can improve the accuracy of the analysis of the performance parameters of the resonant cavity.

Description

Technical Field

[0001] This disclosure relates to the field of quantum computing, and in particular to a method, apparatus and system for determining the performance parameters of a resonant cavity, as well as a computer device. Background Technology

[0002] A resonant cavity is a physical structure that can store and amplify electromagnetic waves of a specific frequency. It is usually made of metal or superconducting materials with specific geometries. By using boundary conditions, electromagnetic waves can be formed into standing waves, thereby achieving efficient energy storage.

[0003] With the rapid development of quantum computing technology, superconducting quantum computing has attracted much attention due to its excellent scalability and process compatibility. The non-destructive readout of superconducting qubits relies on the superconducting resonant cavity that is dispersion-coupled to them; therefore, the performance of the resonant cavity is crucial for qubit readout. High-performance resonant cavities enable faster and higher-fidelity quantum measurements, which is essential for improving the overall performance of quantum computers.

[0004] However, there is a problem of low accuracy in analyzing the performance parameters of resonant cavities. Summary of the Invention

[0005] Therefore, in response to the above-mentioned technical problems, this disclosure provides a method, apparatus, system, and computer equipment for determining resonant cavity performance parameters that can improve the accuracy of analysis of resonant cavity performance parameters.

[0006] In a first aspect, this disclosure provides a method for determining the performance parameters of a resonant cavity, wherein the resonant cavity is used to measure qubits. The method includes: acquiring the signal transmission parameter relationship of the resonant cavity and the signal transmission characteristic coefficients of the resonant cavity at characteristic frequencies, wherein the signal transmission parameter relationship characterizes the relationship between the signal transmission coefficients 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 number of sampling times 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; acquiring multiple candidate transmission coefficients of the resonant cavity at the microwave signal frequency according to the number of sampling times; determining the corresponding signal transmission coefficient of the resonant cavity at the microwave signal frequency based on each candidate transmission coefficient; and fitting the corresponding signal transmission coefficients at each microwave signal frequency based on the signal transmission parameter relationship, obtaining the performance parameters of the resonant cavity when the fitting error converges.

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

[0008] Optionally, 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. This includes: obtaining the initial transmission coefficient acquired for the resonant cavity at the microwave signal frequency and the configured upper limit of the number of sampling times; determining the signal-to-noise ratio at the microwave signal frequency based on the difference between the signal transmission characteristic coefficient and the initial transmission coefficient; and determining the smaller value between the number of sampling times that matches the signal-to-noise ratio and the upper limit of the number of sampling times as the number of sampling times at the microwave signal frequency.

[0009] Based on the above optional content, considering the upper limit of the number of samplings, the number of samplings at the microwave signal frequency can be determined by the number of samplings based on the signal-to-noise ratio matching at the microwave signal frequency. This can avoid the situation where the determined number of samplings is too large and can improve the accuracy of the determination of the number of samplings.

[0010] Optionally, the performance parameters include resonant frequency, total quality factor, internal quality factor, and external quality factor. Based on the signal transmission parameter relationship, the signal transmission coefficients corresponding to each microwave signal frequency are fitted, and the performance parameters of the resonant cavity are obtained when the fitting error converges. This includes: inverting the signal transmission parameter relationship to obtain the inverse signal transmission parameter relationship; fitting each signal transmission coefficient based on the signal transmission parameter relationship, and obtaining the resonant frequency and total quality factor of the resonant cavity when the fitting error converges; fitting the inverse signal transmission coefficient corresponding to each signal transmission coefficient based on the inverse signal transmission parameter relationship, and obtaining the internal quality factor of the resonant cavity when the fitting error converges; the inverse signal transmission coefficient corresponding to any signal transmission coefficient is obtained by inverting the signal transmission coefficient; and the performance parameters including resonant frequency, total quality factor, internal quality factor, and external quality factor are obtained. The external quality factor is determined based on 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 relationship between signal transmission parameters and the internal quality factor based on the relationship between the inverse parameters of signal transmission, the step-by-step fitting can avoid the situation of directly fitting the seven parameters, effectively reducing the size of the fitting parameter space and the difficulty of initial value selection, and improving the accuracy of the resonant cavity performance analysis.

[0012] Optionally, based on the signal transmission parameter relationship, each signal transmission coefficient is fitted to obtain the resonant frequency and total quality factor of the resonant cavity when the fitting error converges. This includes: eliminating 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 signal transmission coefficient; 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; transforming the signal transmission correction parameter relationship 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 first initial value of the resonant frequency and the initial value of the total quality factor as initial values, each signal transmission coefficient is fitted based on the signal transmission parameter relationship to obtain the resonant frequency and the total quality factor of the resonant cavity when the fitting error converges.

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

[0014] Optionally, the process of obtaining the signal transmission correction coefficients corresponding to each signal transmission coefficient includes: obtaining the original curve based on the projection position of each signal transmission correction coefficient in the complex space; selecting multiple feature points in the original curve whose data intervals with the ends satisfy the interval condition, and performing linear fitting on the phase corresponding to each feature point to obtain the initial electrical delay value; using the initial electrical delay value as the initial fitting value and the standard deviation of the distance between each feature point and the center of the first fitting circle as the fitting loss, performing circle fitting based on the projection position of each signal transmission coefficient, and obtaining the electrical delay of the resonant cavity when the fitting loss converges; for each signal transmission coefficient, canceling the phase accumulation caused by the electrical delay 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, the original curve is obtained by considering the projection position of each signal transmission correction coefficient in the complex space. Then, by taking into account the standard deviation of the distance between the two ends of the original curve and the center of the first fitting circle to independently extract the electrical delay parameter, the fitting accuracy of the electrical delay parameter can be improved by removing the phase accumulation caused by the electrical delay.

[0016] Optionally, determining the first signal phase corresponding to each microwave signal frequency based on the projection position of each signal transmission correction coefficient in the complex space includes: performing circle fitting processing based on the projection position of each signal transmission correction coefficient in the complex space to obtain a first fitted circle; using the center of the first fitted circle as the new coordinate origin to update the first coordinate information of each signal transmission correction coefficient 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 circle fitting to fit the projection positions of each signal transmission correction coefficient in the complex space, the projection positions of each signal transmission correction coefficient in the complex space can be considered as a whole. Thus, by updating the first coordinate information of each signal transmission correction coefficient in the complex space through the circle fitting results, the accuracy of determining the first signal phase corresponding to each microwave signal frequency can be improved.

[0018] Secondly, this disclosure also provides a device for determining the performance parameters of a resonant cavity, which is used to measure qubits. The device includes: an acquisition module for acquiring the signal transmission parameter relationship of the resonant cavity and the signal transmission characteristic coefficients of the resonant cavity at characteristic frequencies; a signal transmission parameter relationship for characterizing the relationship between the signal transmission coefficients of the resonant cavity and the microwave signal frequency and performance parameters of the resonant cavity; a determination module for determining the number of samplings at each microwave signal frequency to be sampled, 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; an acquisition module for acquiring multiple candidate transmission coefficients of the resonant cavity at the microwave signal frequency according to the number of samplings; an analysis module for determining the corresponding signal transmission coefficient of the resonant cavity at the microwave signal frequency based on each candidate transmission coefficient; and a processing module for fitting the signal transmission coefficients corresponding to each microwave signal frequency based on the signal transmission parameter relationship, and obtaining the performance parameters of the resonant cavity when the fitting error converges.

[0019] Thirdly, this disclosure provides a system for determining the performance parameters of a resonant cavity, wherein the resonant cavity is used to measure qubits, and the system includes a processor, a microwave generator, and a microwave collector; the processor is connected to the microwave generator and the microwave collector; the microwave generator is used to input a first microwave signal into the resonant cavity; the microwave collector is used to receive a 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; and the processor is used to implement the method of the first aspect or any one of the first aspects.

[0020] Fourthly, this disclosure also provides a computer device. The computer device includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the above-described method for determining the resonant cavity performance parameters.

[0021] Fifthly, this disclosure also provides a computer-readable storage medium. The computer-readable storage medium stores a computer program thereon, which, when executed by a processor, implements the above-described method for determining the resonant cavity performance parameters.

[0022] Sixthly, this disclosure also provides a computer program product. The computer program product includes a computer program that, when executed by a processor, implements the above-described method for determining resonant cavity performance parameters.

[0023] The aforementioned method, apparatus, system, and computer equipment for determining resonant cavity performance parameters acquire the signal transmission parameter relationship of the resonant cavity and the signal transmission characteristic coefficients of the resonant cavity at characteristic frequencies. For each microwave signal frequency to be sampled, 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, the number of sampling times at the microwave signal frequency is determined. According to the number of sampling times, multiple candidate transmission coefficients of the resonant cavity at the microwave signal frequency are acquired. Based on each candidate transmission coefficient, the corresponding signal transmission coefficient of the resonant cavity at the microwave signal frequency is determined. Furthermore, based on the signal transmission parameter relationship, the signal transmission coefficients corresponding to each microwave signal frequency are fitted. The performance parameters of the resonant cavity are obtained when the fitting error converges. Therefore, on the one hand, by adaptively determining the number of sampling times corresponding to the microwave signal frequency, the signal-to-noise ratio imbalance caused by using a fixed average number of sampling times can be improved, thus enhancing the accuracy of resonant cavity performance analysis. On the other hand, by fitting parameters based on pre-set signal transmission parameter relationships, the efficiency of resonant cavity performance parameter analysis can be improved. Attached Figure Description

[0024] Figure 1 This is a schematic diagram illustrating the measurement of the state changes of a quantum bit using a resonant cavity in one embodiment.

[0025] Figure 2This is a flowchart illustrating a method for determining resonant cavity performance parameters in one embodiment;

[0026] Figure 3 This is a flowchart illustrating the process of obtaining a signal transmission coefficient sequence in one embodiment;

[0027] Figure 4 This is a schematic diagram of the data distribution in the complex space in one embodiment;

[0028] Figure 5 This is a schematic diagram illustrating the fitting effect in one embodiment;

[0029] Figure 6 This is a schematic diagram of the fitting effect in another embodiment;

[0030] Figure 7 This is a schematic diagram of the fitting effect in another embodiment;

[0031] Figure 8 This is a schematic diagram of the fitting effect in another embodiment;

[0032] Figure 9 This is a flowchart illustrating the method for determining resonant cavity performance parameters in another embodiment;

[0033] Figure 10 This is a schematic diagram of the fitting effect in another embodiment;

[0034] Figure 11 This is a schematic diagram of the fitting effect in another embodiment;

[0035] Figure 12 This is a schematic diagram of the fitting effect in another embodiment;

[0036] Figure 13 This is a schematic diagram of the fitting effect in another embodiment;

[0037] Figure 14 This is a flowchart illustrating the method for determining resonant cavity performance parameters in another embodiment;

[0038] Figure 15 This is a block diagram of a system for determining resonant cavity performance parameters in one embodiment;

[0039] Figure 16 This is a structural block diagram of a device for determining resonant cavity performance parameters in one embodiment;

[0040] Figure 17 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of this disclosure clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this disclosure.

[0042] In superconducting quantum computers, resonant cavities play a crucial role. First, they are used to couple with superconducting qubits, forming cavity quantum electrodynamics (cQED) systems. This coupling mechanism allows qubits to interact coherently with electromagnetic fields, enabling qubit state readout, manipulation, and interconnection. Second, resonant cavities can also serve as storage units for quantum information, storing quantum states in cavity modes and extending the lifetime of information. Through their high quality factor and precise frequency control, resonant cavities are used to realize high-fidelity quantum state manipulation and multi-qubit coupling networks.

[0043] Non-destructive readout of superconducting qubits relies on a resonant cavity that is dispersion-coupled to them. When the superconducting qubit is in different states, the cavity frequency of the resonant cavity undergoes a dispersion shift. This shift can be achieved by measuring the resonant cavity's frequency. The state of a qubit can be determined by changes in the amplitude or phase of a signal. Therefore, the performance of the resonant cavity is crucial for qubit readout, and a high-performance resonant cavity enables faster and higher-fidelity quantum measurements.

[0044] In microwave measurements, the resonant cavity The signal represents the transmission coefficient from the input port (i.e., port 1) to the output port (i.e., port 2), that is, the amplitude and phase changes of the signal as it travels from the input port to the output port, expressed as:

[0045]

[0046] in, For the complex microwave signal input from the signal source to port 1, The complex microwave signal output from port 2 It is a complex signal containing amplitude and phase information. Expressed in logarithmic form (e.g., dB) or in complex space. In the measurement of resonant cavities, Changes in [the structure / symmetry] can reflect the resonance characteristics of the resonant cavity. Through [the study / analysis]... Signal measurements can be used to analyze the resonant frequency, quality factor (Q value), and energy loss characteristics of the resonant cavity.

[0047] The quality factor (Q value) is used to determine the relationship between energy storage and energy loss in a resonant system at its resonant frequency. The Q value is the ratio of stored energy to lost energy in a resonant system, reflecting its loss characteristics and ability to enhance signals at specific frequencies. A higher Q value indicates lower system losses, longer energy storage time, and stronger selectivity for specific frequencies; a lower Q value indicates higher system losses and a wider frequency response.

[0048] In some embodiments, the quality factor may include an internal quality factor, an external quality factor, and a total quality factor, wherein, considering the internal and external quality factors, the following condition is met:

[0049]

[0050] in, This represents the total quality factor. The internal quality factor is related to the material losses of the resonant cavity itself, including conductor losses, dielectric losses, and the effects of surface defects, and reflects the inherent energy loss of the resonant cavity. The external quality factor is determined by the energy exchange efficiency between the resonant cavity and the coupler. It is affected by the coupler design and 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: firstly, a higher quality factor indicates that when the state of a qubit changes, the dispersion shift can provide greater discriminative power at the same coupling strength, thus achieving a higher signal-to-noise ratio when measuring superconducting qubits, such as... Figure 1 As shown, this disclosure provides a schematic diagram of measuring the state changes of a qubit using a resonant cavity. On the other hand, by measuring the internal quality factor, defects, impurities, and material damage that may be introduced during chip manufacturing can be assessed, while by measuring the external quality factor, the load state of the resonant cavity can be determined, and the rationality of the chip design and the processing accuracy can be evaluated.

[0052] In some embodiments, the resonant cavity can be sampled at different microwave signal frequencies f. Specifically, it involves acquiring the complex microwave signal transmitted from the signal source to the input port at the microwave signal frequency f. The complex microwave signal output from the output port is acquired at the microwave signal frequency f. ,based on It can be obtained Then, the following formula is used for fitting:

[0053]

[0054] in, 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 can be determined by microwave cables, attenuators, filters, amplifiers, etc. Indicates the frequency of the microwave signal. Electrical delay represents the time it takes for a microwave signal to travel from the transmitting port to the receiving port. This indicates the phase caused by the impedance mismatch between the input and output ports of the resonant cavity. This represents the resonant frequency of the resonant cavity, which is related to the physical structural parameters of the resonant cavity. and Here are the performance parameters of the resonant cavity, namely the total quality factor and the equivalent external quality factor; the signal transmission coefficient of the resonant cavity is... .

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

[0064] In some embodiments, the resonant frequency of the resonant cavity can be read from the cavity's information. That is, the cavity's information, including its resonant frequency, can be determined by the cavity's design.

[0065] In some embodiments, the resonant frequency of the resonant cavity can be determined based on calculation or simulation. For example, the resonant frequency of the resonant cavity can be calculated or simulated based on parameters such as the length, width, and distance to ground of the coplanar waveguide transmission line in the design layout of the resonant cavity.

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

[0067] In some embodiments, N measurements can be taken at the characteristic frequency, and the signal transmission coefficient of the resonant cavity at the characteristic frequency can be obtained for the first microwave signal and the second microwave signal obtained in each measurement. The mean or median of the signal transmission coefficients obtained from the N measurements is determined as the signal transmission characteristic coefficient of the resonant cavity at the characteristic frequency. For example, The characteristic frequency is represented by N signal transmission coefficients. The signal transmission coefficient obtained in each measurement If they are the same or different, then 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, 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 by the resonant cavity at the microwave signal frequency.

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

[0070] 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 transmission coefficient may also include the initial transmission coefficient acquired at the microwave signal frequency for the resonant cavity. Specifically, based on the signal ratio between the second microwave signal and the first microwave signal, which matches the microwave signal frequency, the initial transmission coefficient acquired at the microwave signal frequency for the resonant cavity is obtained. Furthermore, based on the difference between the signal transmission characteristic coefficient and the initial transmission coefficient acquired at the microwave signal frequency for the resonant cavity, the number of samplings required for the microwave frequency signal can be determined, i.e., the number of samplings at the microwave signal frequency.

[0071] For each microwave signal frequency to be sampled, the number of sampling times at the microwave signal frequency can be determined 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. There are no restrictions on the implementation methods. The following are some examples of implementation methods.

[0072] In one implementation, the coefficient difference between the signal transmission characteristic coefficient and the initial transmission coefficient acquired by the resonant cavity at the microwave signal frequency is determined. When the coefficient difference is greater than or equal to a preset difference, a first preset number of samplings at the microwave signal frequency is determined; when the coefficient difference is less than the preset difference, a second preset number of samplings at the microwave signal frequency is determined. The first preset number of samplings is less than the second preset number of samplings. Both the first and second preset number of samplings are pre-set numbers, and their specific values ​​can be set according to the actual application scenario.

[0073] In one implementation, the signal-to-noise ratio (SNR) can be proportional to the theoretical parameters of the noise. N represents the number of samples corresponding to the microwave signal frequency. Therefore, if the signal-to-noise ratio (SNR) of each microwave signal frequency is to be increased to the same level as the SNR at frequencies far from the resonant frequency of the resonant cavity, the following steps can be used to determine the number of samples at each microwave signal frequency:

[0074] S11, obtain the initial transmission coefficients acquired for the resonant cavity at the microwave signal frequency, and the configured upper limit of the number of samplings.

[0075] for example, Let the frequency of the microwave signal be denoted as , then the initial transmission coefficient can be expressed as . , The signal ratio is determined based on the ratio between the second microwave signal and the first microwave signal, which are frequency-matched to the microwave signal.

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

[0077] The signal-to-noise ratio (SNR) at microwave signal frequency refers to the SNR obtained with reference to the signal transmission characteristic coefficients. For example, the ratio between the magnitude of the signal transmission characteristic coefficients and the magnitude of the initial transmission coefficients can be determined as the SNR at microwave signal frequency.

[0078] for example, Represented as signal transmission characteristic coefficients, Let it be the initial transmission coefficient, then .

[0079] S13, 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.

[0080] For example, the number of samplings at the microwave signal frequency satisfies:

[0081]

[0082] in, This indicates the number of samples at the microwave signal frequency. This indicates the number of samples for signal-to-noise ratio matching. This indicates the upper limit of the number of samples.

[0083] For example, when When set to 1000, if the number of samplings for signal-to-noise ratio matching calculated using the signal-to-noise ratio relationship exceeds 1000, then the number of samplings at the microwave signal frequency will be set to 1000 to avoid loss of control over the measurement time.

[0084] S206: Collect multiple candidate transmission coefficients of the resonant cavity at the microwave signal frequency according to the number of samplings.

[0085] For example, for each sample, the candidate transmission coefficient can be determined based on the signal ratio between the second microwave signal and the first microwave signal obtained in each sample, and then multiple candidate transmission coefficients matching the number of samples can be obtained.

[0086] S208, based on each candidate transmission coefficient, determines the signal transmission coefficient of the resonant cavity at the microwave signal frequency.

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

[0088] S210, based on the relationship between signal transmission parameters, fits the signal transmission coefficients corresponding to each microwave signal frequency, and obtains the performance parameters of the resonant cavity when the fitting error converges.

[0089] Among them, the convergence of fitting error indicates that the fitting error is minimized. Based on the relationship between signal transmission parameters, the signal transmission coefficients corresponding to each microwave signal frequency are fitted. There are no restrictions on the method to obtain the performance parameters of the resonant cavity when the fitting error converges. The following are some examples of such methods.

[0090] In one implementation, the signal transmission parameter relationship can be inverted to obtain the inverse signal transmission parameter relationship; based on the inverse signal transmission parameter relationship and the signal transmission parameter relationship, the signal transmission coefficients corresponding to each microwave signal frequency are fitted, and the performance parameters of the resonant cavity are obtained when the fitting error converges.

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

[0092]

[0093] The inverse parameter relationship of signal transmission then satisfies:

[0094]

[0095] based on Figure 2The method described above obtains the signal transmission parameter relationship of the resonant cavity and its signal transmission characteristic coefficients at characteristic frequencies. For each microwave signal frequency to be sampled, the number of samplings at that frequency is determined based on the difference between the signal transmission characteristic coefficients and the initial transmission coefficients acquired for the resonant cavity at that frequency. Multiple candidate transmission coefficients are then acquired at each microwave signal frequency based on this number of samplings. The corresponding signal transmission coefficient for each frequency is then determined based on these candidate coefficients. Finally, the signal transmission coefficients for each microwave signal frequency are fitted based on the signal transmission parameter relationship. The resonant cavity performance parameters are obtained when the fitting error converges. Therefore, on the one hand, by adaptively determining the number of samplings corresponding to the microwave signal frequency, the signal-to-noise ratio imbalance caused by using a fixed average number of samplings can be improved, thus enhancing the accuracy of resonant cavity performance analysis. On the other hand, parameter fitting based on pre-set signal transmission parameter relationships can improve the efficiency of resonant cavity performance parameter analysis.

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

[0097] Specifically, such as Figure 3 As shown, this disclosure provides a flowchart for obtaining a signal transmission coefficient sequence. Taking the application of this method to a processor in a 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, according to the number of samplings corresponding to the characteristic frequency, obtain the first microwave signal and the second microwave signal that match the characteristic frequency obtained in each sampling.

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

[0100] S304, based on the signal ratio between the second microwave signal and the first microwave signal that match the characteristic frequency obtained from each sampling, determine the signal transmission coefficient at the characteristic frequency.

[0101] S306, Based on the average of multiple signal transmission coefficients that match the number of samplings corresponding to the characteristic frequency, determine the signal transmission characteristic coefficients at the characteristic frequency.

[0102] S308, for each microwave signal frequency to be sampled in the frequency sequence, according to the sampling number corresponding to the microwave signal frequency, obtain the first microwave signal and the second microwave signal that match the microwave signal frequency obtained in each sampling; the signal ratio between the second microwave signal that matches the microwave signal frequency and the first microwave signal characterizes the candidate transmission coefficient at the microwave signal frequency.

[0103] S310, based on the average of multiple candidate transmission coefficients that match the number of samplings corresponding to the microwave signal frequency, determine the signal transmission coefficient at the microwave signal frequency.

[0104] S312, obtain a signal transmission coefficient sequence containing signal transmission characteristic coefficients and multiple signal transmission coefficients.

[0105] based on Figure 3 The content shown addresses the signal-to-noise ratio imbalance caused by the existing scanning method with a fixed number of average scans. It proposes an adaptive dynamic averaging test method, which can improve the signal-to-noise ratio near the resonant frequency of the resonant cavity while improving measurement efficiency, thereby increasing the accuracy of resonant cavity performance analysis.

[0106] In one embodiment, the performance parameters of the resonant cavity include resonant frequency, overall quality factor, internal quality factor, and external quality factor. Based on the relationship between signal transmission parameters, the signal transmission coefficients corresponding to each microwave signal frequency are fitted. The implementation method for obtaining the performance parameters of the resonant cavity, assuming the fitting error converges, includes the following steps:

[0107] S21, reverse the relationship of signal transmission parameters to obtain the inverse relationship of signal transmission parameters.

[0108] The content regarding the relationship between signal transmission parameters and the relationship between inverse signal transmission parameters can be found in the description in S210.

[0109] S22, based on the relationship between signal transmission parameters, fits the transmission coefficients of each signal, and obtains the resonant frequency and total quality factor of the resonant cavity when the fitting error converges.

[0110] Among them, the resonant frequency and total quality factor of the resonant cavity are obtained by fitting each signal transmission coefficient based on the relationship of signal transmission parameters, provided that the fitting error converges. There are no restrictions on the methods. The following examples illustrate the possible implementation methods.

[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 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 and the signal transmission parameter relationship, each signal transmission coefficient is fitted, and the resonant frequency and total quality factor of the resonant cavity are obtained when the fitting error converges.

[0112] For example, Indicates the frequency of the microwave signal. Indicates the phase of the first signal. This represents the total quality factor. Let the first resonant power be represented, then the relationship of the first phase change parameters can satisfy:

[0113]

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

[0115] Among them, based on the inverse parameter relationship of signal transmission, the inverse coefficient of signal transmission corresponding to each signal transmission coefficient is fitted. Under the condition that the fitting error converges, the internal quality factor of the resonant cavity can be obtained in any way. The following are examples of possible implementation methods.

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

[0117] S24, obtain performance parameters including resonant frequency, total quality factor, internal quality factor and external quality factor; the external quality factor is determined based on the total quality factor and internal quality factor.

[0118] For example, the relationship between the external quality factor, the total quality factor, and the internal quality factor satisfies:

[0119]

[0120] in, Indicates the external quality factor. This represents the internal quality factor of the resonant cavity when the fitting error converges. This represents the overall quality factor of the resonant cavity when the fitting error converges.

[0121] Based on the content of S21-S24, the overall quality factor is obtained based on the relationship between signal transmission parameters, and the internal quality factor is obtained based on the relationship between the inverse parameters of signal transmission. Thus, by performing step-by-step fitting, the direct fitting of the seven parameters can be avoided, which effectively reduces the size of the fitting parameter space and the difficulty of initial value selection, thereby improving the accuracy of the resonant cavity performance analysis.

[0122] In some embodiments, based on the relationship between signal transmission parameters, each signal transmission coefficient is fitted, and the resonant frequency and total quality factor (i.e., S22) of the resonant cavity are obtained when the fitting error converges. This includes the following steps:

[0123] S221, eliminate phase accumulation caused by electrical delay, 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, due to Signals of different frequencies in the data cause [the following issues] in the line. The different velocity phases accumulate, therefore The distribution of data in complex space is as follows Figure 4 As shown in (a) above, it exhibits a spiral distribution. Therefore, by removing... Data power delay The resulting phase accumulation, after removing the electrical delay phase accumulation, results in the following data in complex space: Figure 4 As shown in (b) in the figure, it is a standard circular distribution. Therefore, based on this, the value of the electrical delay parameter can be optimized using the gradient descent optimization algorithm.

[0125] For example, regarding 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] in, This represents the signal transmission correction coefficient.

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

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

[0130] In some embodiments, a circle fitting process can be performed based on the projection positions of each signal transmission correction coefficient in the complex space to obtain a first fitted circle; the center of the first fitted circle is used as the new coordinate origin to update the first coordinate information of each signal transmission correction coefficient in the complex space; based on the updated first coordinate information, the first signal phase corresponding to each microwave signal frequency is determined.

[0131] For example, the first coordinate information of the signal transmission correction coefficient in complex space includes the origin of the coordinate system. By translating the origin of the coordinate system of the signal transmission correction coefficient in complex space to the center of the first fitted circle, the first coordinate information of each signal transmission correction coefficient in complex space can be updated.

[0132] For example, given the initial values ​​for circle fitting, performing circle fitting based on the projection positions of each signal transmission correction coefficient in the complex space yields the following result: Figure 5 The diagram shows the fitting effect. By taking the center of the first fitted circle as the new origin and updating the first coordinate information of each signal transmission correction coefficient in complex space, we can obtain the following: Figure 6 A schematic diagram showing the coordinate translation results.

[0133] In one embodiment, a first fitted circle can be obtained by performing circle fitting based on the projection positions of each signal transmission correction coefficient in the complex space; and the first signal phase corresponding to each microwave signal frequency can be determined based on the tangent values ​​of each signal transmission correction coefficient relative to the center of the first fitted circle.

[0134] S223, 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.

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

[0136]

[0137] Among them, in the relationship of the first phase change parameters Indicates the phase of the first signal. This represents the total quality factor. Indicates the first resonant frequency. This indicates the frequency of the microwave signal.

[0138] S224, based on the first phase change parameter relationship, perform phase fitting 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.

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

[0140] for example, This represents the signal transmission correction coefficient at microwave signal frequency f. The modulus information representing the signal transmission correction coefficient at microwave signal frequency f allows us to determine the minimum value. The corresponding microwave signal frequency f is determined as the first resonant frequency. initial fitted values .

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

[0142] For example, taking a preset decibel level of 3dB as an example, Indicates frequency bandwidth. Let represent the initial fitted value of the total quality factor, then .

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

[0144] For example, This represents the first frequency value in the first phase change parameter relationship. Let represent the first phase value in the first phase change parameter relationship, then the first signal phase in the first phase change parameter relationship. initial fitted values satisfy:

[0145]

[0146] Based on the above, the initial fitted values ​​corresponding to the first phase change parameter relationship can be determined. , and Then, using the corresponding initial fitting values ​​as initial values, phase fitting is performed on the first signal phase corresponding to each microwave signal frequency. This allows extraction of the first initial value of the resonant frequency, the initial value of the total quality factor, and the initial value of the first signal phase. A schematic diagram of the fitting results can be shown below. Figure 7 As shown.

[0147] S225, using the initial values ​​of the resonant frequency and the total quality factor as initial values, fits the signal transmission coefficients based on the relationship between the signal transmission parameters, and obtains the resonant frequency and the total quality factor of the resonant cavity when the fitting error converges.

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

[0149]

[0150] in, , and These represent the first initial value of the resonance frequency, the initial value of the total quality factor, and the initial value of the first signal phase, respectively, extracted based on the relationship of the first phase change parameters. This represents the electrical delay of the resonant cavity obtained based on S31-S33. This represents the target value for matching the first initial value of the resonant frequency. This represents the target value that matches the initial value of the total quality factor. This represents the first initial value of the background phase. This represents the initial value of the background attenuation magnitude. This represents the first initial phase value caused by the impedance mismatch between the input and output ports of the resonant cavity. This represents the first modulus value corresponding to the equivalent external quality factor. This represents the first initial value of the electrical delay. Let the center of the first fitted circle be . This represents the radius of the first fitted circle.

[0151] For example, the target value of the resonant frequency first initial value matching, the target value of the total quality factor initial value matching, the background phase first initial value, the background attenuation amplitude first initial value, the phase first initial value caused by the impedance mismatch between the input port and the output port of the resonant cavity, the first magnitude value corresponding to the equivalent external quality factor, and the electrical delay first initial value can be used as initial values. Based on the relationship of signal transmission parameters, each signal transmission coefficient is fitted. When the fitting error is minimized, the corresponding resonant frequency and total quality factor are determined as the resonant frequency and total quality factor of the resonant cavity obtained when the fitting error converges.

[0152] For example, based on the content of S221-S225, we can obtain the following: Figure 8The fitting results are shown in (a), (b) and (c) in the figure.

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

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

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

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

[0157] S32, select multiple feature points in the original curve whose data interval between the curve ends meets the interval condition, and perform linear fitting on the phase corresponding to each feature point to obtain the initial value of electrical delay.

[0158] In some embodiments, the curve endpoint includes the curve start point and curve end point of the original curve. Selecting multiple feature points in the original curve whose data intervals with respect to the curve endpoint satisfy an interval condition includes: if the distance between a data point in the original curve and the curve start point is within a first preset range, then the data point in the original curve is determined as a feature point; or, if the distance between a data point in the original curve and the curve end point is within a second preset range, then the data point in the original curve is determined as a feature point. For example, the first 10% of the data points in the original curve can be selected as feature points, or the last 10% of the 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 electrical delay, selecting multiple feature points based on the ends of the original curve can improve accuracy.

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

[0161] S33, using the initial value of electrical delay as the initial value for fitting, and the standard deviation of the distance between each feature point and the center of the first fitting circle as the fitting loss, performs circle fitting based on the projection position of each signal transmission coefficient, and obtains the electrical delay of the resonant cavity when the fitting loss converges.

[0162] For example, a first fitted circle can be obtained by performing circle fitting based on the projection positions of each signal transmission correction coefficient in the complex space.

[0163] Among them, the convergence of the fitting loss represents the minimum fitting loss. For example, based on the gradient descent method, the electrical delay corresponding to the minimum fitting loss can be determined as the electrical delay of the resonant cavity.

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

[0165] Based on the content of S31-S34, the original curve is obtained by considering the projection position of each signal transmission correction coefficient in the complex space. Then, by taking into account the standard deviation of the distance between the two ends of the original curve and the center of the first fitting circle to independently extract the electrical delay parameter, the fitting accuracy of the electrical delay parameter can be improved by removing the phase accumulation caused by the electrical delay.

[0166] Combining the content of S31-S34, such as Figure 9 As shown, this disclosure provides a schematic diagram for obtaining the electrical delay of a resonant cavity. Taking the application of this method to a processor in a resonant cavity performance parameter determination system as an example, the method includes the following steps:

[0167] S902, based on the projection positions of each signal transmission correction coefficient in the complex space, obtains the original curve.

[0168] S904 selects either the first 10% or the last 10% of data points from the original curve as multiple feature points.

[0169] S906, perform linear fitting on the phase corresponding to each feature point to obtain the fitting slope, and determine the product of the fitting slope and the preset value as the initial value of the electrical delay.

[0170] S908, the initial value of electrical delay is used as the initial value for fitting, 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. If the fitting loss is minimized when the initial value of electrical delay is optimized using the gradient descent method, the electrical delay of the resonant cavity is obtained.

[0171] S910, for each signal transmission coefficient, cancels the phase accumulation caused by electrical delay based on the signal transmission coefficient to obtain the signal transmission correction coefficient corresponding to the signal transmission coefficient.

[0172] For example, the signal transmission correction factor and the signal transmission factor satisfy: If the signal transmission coefficient is known, then the signal transmission correction coefficient corresponding to the signal transmission coefficient can be obtained.

[0173] Based on the content of S902-S910, the original curve is obtained by considering the projection position of each signal transmission correction coefficient in the complex space. Then, by taking into account the standard deviation of the distance between the two ends of the original curve and the center of the first fitting circle to independently extract the electrical delay parameter, the fitting accuracy of the electrical delay parameter can be improved by removing the phase accumulation caused by the electrical delay.

[0174] In one embodiment, based on the inverse parameter relationship of signal transmission, the inverse coefficients of signal transmission corresponding to each signal transmission coefficient are fitted, and the internal quality factor of the resonant cavity (i.e., S23) is obtained when the fitting error converges. This includes the following steps:

[0175] S231, eliminate phase accumulation caused by electrical delay, 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] For example, regarding the inverse parameter relationship of signal transmission, by setting the electrical delay to 0, the phase accumulation caused by the electrical delay can be eliminated, and the inverse correction parameter relationship of signal transmission corresponding to the inverse parameter relationship of signal transmission can be obtained.

[0177] For example, Represents the inverse correction coefficient for signal transmission. Let represent the inverse coefficient of signal transmission. Then, the inverse coefficient of signal transmission and the inverse correction coefficient of signal transmission satisfy the following: .

[0178] Referring to S231, given the inverse coefficient of signal transmission corresponding to the signal transmission coefficient, the relationship between the inverse coefficient of signal transmission and the inverse correction coefficient of signal transmission is as follows: This allows us to obtain the signal transmission inverse correction coefficients corresponding to each signal transmission inverse coefficient.

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

[0180] S232, perform circle fitting based on the projection positions of each signal transmission inverse correction coefficient in the complex space to obtain the second fitted circle.

[0181] For example, based on the content of S232, we can obtain the following: Figure 10 The diagram shows the fitting results.

[0182] S233, take the center of the second fitted circle as the new origin of coordinates, and update the second coordinate information of each signal transmission inverse correction coefficient in complex space.

[0183] For example, based on the content of S233, we can obtain the following: Figure 11 The diagram shows the fitting results.

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

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

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

[0187]

[0188] In the relationship of the second phase change parameters... Indicates the phase of the second signal. Indicates the internal quality factor. Indicates the frequency of the microwave signal. This indicates the second resonant frequency.

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

[0190] Among them, the variables involved in the relationship of the second phase change parameters , and The corresponding initial fitted values ​​can be determined in the following ways.

[0191] For example, the initial fitted value of the resonant frequency in the second phase change parameter relationship is the same as the resonant frequency of the resonant cavity obtained when the fitting error converges.

[0192] For example, the initial fitted value of the internal quality factor in the second phase change parameter relationship. satisfy:

[0193]

[0194] in, This represents the radius of the second fitted circle. This represents the first modulus of the equivalent external quality factor obtained when the fitting error converges. The first initial value of the background attenuation magnitude obtained when the fitting error converges, i.e., the fitting result in S225 when the fitting error converges, includes... and .

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

[0196] For example, This represents the first frequency value in the second phase change parameter relationship. This represents the first phase value in the second phase change parameter relationship. Let represent the initial fitted value of the second resonant frequency in the second phase change parameter relationship, then the second signal phase in the second phase change parameter relationship. initial fitted values satisfy:

[0197]

[0198] Therefore, based on the above, the initial fitted values ​​corresponding to the second phase change parameter relationship can be determined. , and Then, using the corresponding initial fitting values ​​as initial values, phase fitting is performed on the second signal phase corresponding to each microwave signal frequency. This yields 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. The fitting results can be obtained as follows: Figure 12 As shown.

[0199] S237 uses the second initial value of the resonant frequency and the initial value of the internal quality factor as initial values. Based on the inverse parameter relationship of signal transmission, the inverse coefficients of each signal transmission are fitted, and the internal quality factor of the resonant cavity is obtained when the fitting error converges.

[0200] For example, the second initial value of the resonant frequency, the initial value of the internal quality factor, the second initial value of the background phase, the second initial value of the background attenuation amplitude, the second initial value of the phase caused by the impedance mismatch between the input and output ports of the resonant cavity, the second magnitude value corresponding to the equivalent external quality factor, and the second initial value of the electrical delay satisfy the following:

[0201]

[0202] in, , and These represent the second initial value of the resonance frequency, the initial value of the internal quality factor, and the initial value of the second signal phase, respectively, extracted based on the relationship of the second phase change parameters. This represents the target value for matching the second initial value of the resonant frequency. This indicates the target value to which the initial value of the internal quality factor matches. This represents the second initial value of the background phase. This represents the second initial value of the background attenuation magnitude. This represents the second initial phase value caused by the impedance mismatch between the input and output ports of the resonant cavity. This represents the second modulus value corresponding to the equivalent external quality factor. This represents the second initial value of the electrical delay. Indicates the center of the second fitted circle. This represents the radius of the second fitted circle.

[0203] For example, the target value of the second initial value of the resonant frequency, the target value of the initial value of the internal quality factor, the second initial value of the background phase, the second initial value of the background attenuation amplitude, the second initial value of the phase caused by the impedance mismatch between the input and output ports of the resonant cavity, the second magnitude value corresponding to the equivalent external quality factor, and the second initial value of the electrical delay can be used as initial values. Based on the inverse parameter relationship of signal transmission, each inverse coefficient of signal transmission is fitted. When the fitting error is minimized, the corresponding internal quality factor is determined as the internal quality factor of the resonant cavity obtained when the fitting error converges.

[0204] Specifically, the internal quality factor of the resonant cavity can be obtained by fitting the target value of the second initial value of the resonant frequency, the target value of the initial value of the internal quality factor, the second initial value of the background phase, the second initial value of the background attenuation amplitude, the second initial value of the phase caused by the impedance mismatch of the input and output ports of the resonant cavity, the second magnitude value corresponding to the equivalent external quality factor, and the second initial value of the electrical delay using the following inverse signal transmission parameter relationship; the inverse signal transmission parameter relationship satisfies:

[0205]

[0206] The content of S231-S237 can be adapted to the description of S221-S225 by referring to the content of S231-S237. For example, based on the content of S231-S237, the following can be obtained: Figure 13 The fitting results are shown.

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

[0208] In summary, such as Figure 14 As shown, this disclosure provides a flowchart of a method for determining resonant cavity performance parameters. Taking the application of this method to a processor in a resonant cavity performance parameter determination system as an example, the method includes the following steps:

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

[0210] Specifically, the resonant frequency and overall quality factor of the resonant cavity can be obtained based on S1404-S1414 when the fitting error converges. The internal quality factor of the resonant cavity can be obtained based on S1416-S1426 when the fitting error converges.

[0211] S1404, perform circle fitting based on the projection positions of the signal transmission correction coefficients corresponding to each signal transmission coefficient in the complex space to obtain the first fitted circle.

[0212] S1406, take the center of the first fitted circle as the new coordinate origin, and update the first coordinate information of each signal transmission correction coefficient in the complex space.

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

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

[0215] S1412, based on the first phase change parameter relationship, perform phase fitting 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.

[0216] S1414, with the initial values ​​of the resonant frequency and the total quality factor as initial values, fits the signal transmission coefficients based on the relationship between the signal transmission parameters, and obtains the resonant frequency and the total quality factor of the resonant cavity when the fitting error converges.

[0217] S1416, perform circle fitting based on the projection positions of each signal transmission inverse correction coefficient in the complex space to obtain the second fitted circle.

[0218] The inverse coefficient of signal transmission corresponding to any signal transmission coefficient is obtained by inverting the signal transmission coefficient.

[0219] S1418, take the center of the second fitted circle as the new coordinate origin, and update the second coordinate information of each signal transmission inverse correction coefficient in complex space.

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

[0221] S1422, the inverse signal transmission correction parameter relationship after inverting the signal transmission correction parameter relationship is transformed to obtain the corresponding second phase change parameter relationship.

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

[0223] S1426, using the second initial value of the resonant frequency and the initial value of the internal quality factor as initial values, and based on the inverse parameter relationship of the signal transmission corresponding to the signal transmission parameter relationship, fit each inverse coefficient of the signal transmission, and obtain the internal quality factor of the resonant cavity when the fitting error converges.

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

[0225] The contents of S1402-S1428 can be referred to the aforementioned content description, and will not be repeated here.

[0226] In the above embodiments, the steps of fitting the electrical delay (corresponding to S1402) and determining the external quality factor are removed. Apart from step 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) adjusts the signal transmission correction coefficient (S). 21,de The data was fitted to obtain the total quality factor. The second branch (corresponding to S1416 to S1426) has an inverse correction coefficient for signal transmission (S). 21,de The internal quality factor is obtained by fitting the inverse data. .

[0227] This disclosure can be tested using an adaptive dynamic averaging method. Signal with frequency The changes were then fitted step by step. and This method achieves a nearly consistent signal-to-noise ratio across the entire measurement frequency band through dynamic averaging measurements at different frequencies. The step-by-step fitting avoids directly fitting all seven parameters, with each step fitting a maximum of three parameters. This effectively reduces the size of the fitting parameter space and the difficulty of initial value selection. Signal fitting, when and When the difference is too large, an accurate result can be obtained. Value. When the fitting error is large, this step-by-step fitting method is beneficial for troubleshooting and can therefore solve the problem more quickly.

[0228] In summary, the method provided in this disclosure can be based on the frequency of the microwave signal to be sampled. Signal transmission coefficient at modulus The sampling frequency is adaptively adjusted at each frequency point to maintain relative consistency of the signal-to-noise ratio across all frequencies. This is achieved by... The signal fitting process is broken down into steps such as calibrating the electrical delay, circular fitting, and phase fitting. This reduces the parameter space for each fitting step, improving fitting efficiency and success rate. Through... Determining by stepwise fitting of the signal , and then combined with Signal determined To calculate .

[0229] Furthermore, by optimizing and removing the phase accumulation caused by electrical delay, based on Extracting the electrical delay by using the standard deviation of the data at both ends relative to the distance from the center can improve the fitting accuracy of the electrical delay of the resonant cavity.

[0230] In some embodiments, such as Figure 15 As shown, this disclosure provides a system for determining the performance parameters of a resonant cavity, wherein the resonant cavity is used to measure qubits. The resonant cavity performance parameter determination system 150 includes a processor 1502, a microwave acquisition unit 1504, and a microwave generator 1506, with the processor 1502 connected to the microwave acquisition unit 1504 and the microwave generator 1506.

[0231] Specifically, the microwave generator 1506 is used to input a first microwave signal into the resonant cavity 160; the microwave acquisition unit 1504 is used to receive a 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 1502 is used to acquire the signal transmission parameter relationship of the resonant cavity and the 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 performance parameters of the resonant cavity; for each microwave signal frequency to be sampled, 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, the number of sampling times at the microwave signal frequency is determined; according to the number of sampling times, multiple candidate transmission coefficients of the resonant cavity at the microwave signal frequency are acquired; the statistical value of each candidate transmission coefficient is determined as the signal transmission coefficient corresponding to the resonant cavity at the microwave signal frequency; based on the signal transmission parameter relationship, the signal transmission coefficients corresponding to each microwave signal frequency are fitted, and the performance parameters of the resonant cavity are obtained when the fitting error converges.

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

[0233] The transmission coefficient can include the signal transmission characteristic coefficient of the resonant cavity at the characteristic frequency, the candidate transmission coefficients 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 a first microwave signal into the resonant cavity and acquire the second microwave signal output by the resonant cavity received by the microwave acquisition unit. Then, based on the signal ratio between the second microwave signal and the first microwave signal, which match the microwave signal frequency, the signal transmission coefficient of the resonant cavity can be determined. Here, the first microwave signal is the aforementioned... The second microwave signal is the aforementioned The signal transmission coefficient is as described above. .

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

[0236] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0237] Based on the same inventive concept, this disclosure also provides a resonant cavity performance parameter determination device for implementing the resonant cavity performance parameter determination method described above. The solution provided by this device is similar to the solution described in the above method; therefore, the specific limitations in one or more resonant cavity performance parameter determination device embodiments provided below can be found in the limitations of the resonant cavity performance parameter determination method described above, and will not be repeated here.

[0238] In some embodiments, such as Figure 16 As shown, this disclosure provides a device for determining the performance parameters of a resonant cavity. The resonant cavity is used to measure qubits. The device includes: an acquisition module 1602, used to acquire the signal transmission parameter relationship of the resonant cavity and the 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 performance parameters of the resonant cavity; a determination module 1604, used to determine the number of samplings at each microwave signal frequency to be sampled, 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; an acquisition module 1606, used to acquire multiple candidate transmission coefficients of the resonant cavity at the microwave signal frequency according to the number of samplings; an analysis module 1608, used 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, used to fit the signal transmission coefficients corresponding to each microwave signal frequency based on the signal transmission parameter relationship, and obtain the performance parameters of the resonant cavity when the fitting error converges.

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

[0240] In some embodiments, the performance parameters include resonant frequency, total quality factor, internal quality factor, and external quality factor; the processing module 1610 is further configured to: invert the signal transmission parameter relationship to obtain the inverse signal transmission parameter relationship; fit each signal transmission coefficient based on the signal transmission parameter relationship, and obtain the resonant frequency and total quality factor of the resonant cavity when the fitting error converges; fit the inverse signal transmission coefficient corresponding to each signal transmission coefficient based on the inverse signal transmission parameter relationship, and obtain the internal quality factor of the resonant cavity when the fitting error converges; the inverse signal transmission coefficient corresponding to any signal transmission coefficient is obtained by inverting the signal transmission coefficient; obtain performance parameters including resonant frequency, total quality factor, internal quality factor, and external quality factor; the external quality factor is determined based on 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, 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; determine the first signal phase corresponding to each microwave signal frequency based on the projection position of each signal transmission correction coefficient in the complex space; transform the signal transmission correction parameter relationship 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; perform phase fitting on the first signal phase corresponding to each microwave signal frequency based on the first phase change parameter relationship to obtain the first initial value of the resonant frequency and the initial value of the total quality factor of the resonant cavity; use the first initial value of the resonant frequency and the initial value of the total quality factor as initial values, and fit each signal transmission coefficient based on the signal transmission parameter relationship to obtain the resonant frequency and the total quality factor of the resonant cavity when the fitting error converges.

[0242] In some embodiments, the processing module 1610 is further configured to: obtain an original curve based on the projection positions of each signal transmission correction coefficient in the complex space; select multiple feature points in the original curve whose data intervals with the ends satisfy the interval condition, perform linear fitting on the phase corresponding to each feature point, and obtain an initial electrical delay value; use the initial electrical delay value as the initial fitting value and the standard deviation of the distance between each feature point and the center of the first fitting circle as the fitting loss, perform circle fitting based on the projection positions of each signal transmission coefficient, and obtain the electrical delay of the resonant cavity when the fitting loss converges; for each signal transmission coefficient, cancel the phase accumulation caused by the electrical delay based on the signal transmission coefficient to obtain the 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 projection positions of each signal transmission correction coefficient in the complex space to obtain a first fitted circle; use the center of the first fitted circle as the new coordinate origin to update the first coordinate information of each signal transmission correction coefficient in the complex space; and determine the first signal phase corresponding to each microwave signal frequency based on the updated first coordinate information.

[0244] Each module in the aforementioned resonant cavity performance parameter determination device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in the processor of the resonant cavity performance parameter determination system in hardware form or independent of it, or they can be stored in the memory of the resonant cavity performance parameter determination system in software form, so that the processor can call and execute the corresponding operations of each module.

[0245] In some embodiments, this disclosure provides a computer device, which may be a server, and its internal structure diagram may be as follows: Figure 17 As shown, the computer device includes a processor, memory, input / output (I / O) interfaces, and a communication interface. The processor, memory, and I / O interfaces are connected via a system bus, and the communication interface is also connected to the system bus via the I / O interfaces. The processor provides computational and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and a database. The internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The database stores data involved in the determination of resonant cavity performance parameters. The I / O interfaces are used for information exchange between the processor and external devices. The communication interface is used for communication with external terminals via a network connection. When the computer program is executed by the processor, it implements a method for determining resonant cavity performance parameters.

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

[0247] In some embodiments, this disclosure provides a computer device including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of the method embodiments described above.

[0248] In some embodiments, this disclosure provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the above-described method embodiments.

[0249] In some embodiments, this disclosure provides a computer program product including a computer program that, when executed by a processor, implements the steps of the method embodiments described above.

[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 used for analysis, stored data, and displayed data) involved in this disclosure are all information and data authorized by the user or fully authorized by all parties, and the collection, use, and processing of related data must comply with the relevant laws, regulations, and standards of the relevant regions and areas. Furthermore, the recipient may choose not to authorize the distribution of their information and related data, or may refuse or conveniently refuse to receive push notifications.

[0251] In the process of collecting and processing relevant data in practical applications, this disclosure should strictly comply with the requirements of relevant local laws and regulations, obtain the informed consent or separate consent of the personal information subject, and carry out subsequent data use and processing within the scope of laws and regulations and the authorization of the personal information subject.

[0252] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this 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 memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this disclosure may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this disclosure may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, etc., and are not limited to these.

[0253] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0254] The embodiments described above are merely illustrative of several implementations of this disclosure, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent disclosure. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this disclosure, and these all fall within the protection scope of this disclosure. Therefore, the protection scope of this disclosure should be determined by the appended claims.

Claims

1. A method of determining a performance parameter of a resonator cavity for measuring a quantum bit, the method comprising: determining a quality factor of the resonator cavity; determining a frequency of the resonator cavity; and determining a coupling strength between the resonator cavity and the quantum bit based on the determined quality factor and the determined frequency. The method comprises: obtaining a signal transmission parameter relationship of a resonant cavity and signal transmission characteristic coefficients of the resonant cavity at characteristic frequencies, wherein the signal transmission parameter relationship is used to represent a relationship between signal transmission coefficients of the resonant cavity and microwave signal frequencies and performance parameters of the resonant cavity; for each microwave signal frequency to be sampled, determining a sampling number at the microwave signal frequency based on a difference between the signal transmission characteristic coefficients and initial transmission coefficients 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 signal transmission coefficients of the resonant cavity at the microwave signal frequency based on the candidate transmission coefficients; based on the signal transmission parameter relationship, fitting the signal transmission coefficients respectively corresponding to the microwave signal frequencies, and obtaining performance parameters of the resonant cavity in a case where fitting errors converge; wherein the performance parameters comprise a resonance frequency, a total quality factor, an internal quality factor and an external quality factor; the method of fitting the signal transmission coefficients respectively corresponding to the microwave signal frequencies based on the signal transmission parameter relationship, and obtaining the performance parameters of the resonant cavity in a case where fitting errors converge, comprises: The signal transmission parameter relationship is inverted to obtain a signal transmission inverse parameter relationship; phase accumulation caused by electrical delay is eliminated to obtain a signal transmission correction parameter relationship corresponding to the signal transmission parameter relationship; phase accumulation caused by electrical delay is eliminated, and an original curve is obtained based on the respective projection positions of the signal transmission coefficients in complex space; a plurality of feature points in the original curve that satisfy an interval condition with the end portions are selected, linear fitting is performed on the respective phases corresponding to the feature points to obtain an electrical delay initial value; the electrical delay initial value is taken as a fitting initial value, a standard deviation of the distance between the feature points and the center of a first fitting circle is taken as a fitting loss, circle fitting is performed based on the respective projection positions of the signal transmission coefficients, and in the case of convergence of the fitting loss, 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 a signal transmission correction coefficient corresponding to the signal transmission coefficient; based on the respective projection positions of the signal transmission correction coefficients in complex space, first signal phases corresponding to the respective microwave signal frequencies are determined; the signal transmission correction parameter relationship is converted 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; based on the first phase change parameter relationship, phase fitting is performed on the first signal phases corresponding to the respective microwave signal frequencies to obtain a first initial value of the resonance frequency and an initial value of the total quality factor of the resonant cavity; based on the signal transmission parameter relationship, fitting is performed on the signal transmission coefficients with the first initial value of the resonance frequency and the initial value of the total quality factor as the initial values, and in the case of convergence of the fitting error, the resonance frequency and the total quality factor of the resonant cavity are obtained; based on the signal transmission inverse parameter relationship, fitting is performed on the signal transmission inverse coefficients corresponding to the respective signal transmission coefficients, and in the case of convergence of the fitting error, the internal quality factor of the resonant cavity is obtained; the signal transmission inverse coefficient corresponding to any signal transmission coefficient is obtained by inverting the signal transmission coefficient; performance parameters including the resonance frequency, the total quality factor, the internal quality factor, and an external quality factor are obtained; the external quality factor is determined according to the total quality factor and the internal quality factor.

2. The method of claim 1, wherein, The difference between the signal transmission characteristic coefficient and the initial transmission coefficient collected for the resonant cavity at the microwave signal frequency is used to determine the sampling number at the microwave signal frequency, which includes: An initial transmission coefficient collected for the resonant cavity at the microwave signal frequency and an upper limit of the sampling number are obtained; A signal-to-noise ratio at the microwave signal frequency is determined based on the difference between the signal transmission characteristic coefficient and the initial transmission coefficient; 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 at the microwave signal frequency.

3. The method of claim 1, wherein, The method comprises the following steps: The method comprises the following steps: The method comprises the following steps: The method comprises the following steps:

4. The method of claim 1, wherein, The method comprises the following steps: The method comprises the following steps: The system comprises a processor, a microwave generator and a microwave collector; the processor is connected to the microwave generator and the microwave collector; 5. A resonator performance parameter determination system, the resonator being for measuring a quantum bit, characterized by, The microwave generator is used for inputting a first microwave signal into a resonant cavity; The microwave collector is used for receiving a second microwave signal output by the resonant cavity; a signal ratio between the second microwave signal and the first microwave signal is used for representing a transmission coefficient of the resonant cavity; The processor is used for implementing the method according to any one of claims 1 to 4. The device comprises:

6. A resonator performance parameter determination apparatus, the resonator being for measuring a quantum bit, characterized by, An acquisition module is 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 for representing a relationship between a signal transmission coefficient of the resonant cavity and microwave signal frequencies and performance parameters of the resonant cavity; A determination module is configured to determine, for each microwave signal frequency to be sampled, 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 is 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 is configured to determine, based on each candidate transmission coefficient, a signal transmission coefficient of the resonant cavity at the microwave signal frequency; A processing module is configured to fit, based on the signal transmission parameter relationship, the signal transmission coefficients respectively corresponding to each microwave signal frequency, and obtain a performance parameter of the resonant cavity in a case where a fitting error converges. ​ The performance parameters include a resonance frequency, a total quality factor, an internal quality factor and an external quality factor; the processing module is further configured to: obtain a signal transmission inverse parameter relationship by inverting the signal transmission parameter relationship; eliminate phase accumulation caused by electrical delay to obtain a signal transmission correction parameter relationship corresponding to the signal transmission parameter relationship; eliminate phase accumulation caused by electrical delay, and obtain an original curve based on respective projection positions of the signal transmission coefficients in a complex space; select a plurality of feature points in the original curve that satisfy an interval condition with respect to data intervals between ends; perform linear fitting on respective phases of the feature points to obtain an electrical delay initial value; perform circular fitting based on the respective projection positions of the signal transmission coefficients, taking the electrical delay initial value as a fitting initial value and a standard deviation of distances between the feature points and a center of a first fitting circle as a fitting loss, and obtain the electrical delay of the resonant cavity in a case where the fitting loss converges; for each signal transmission coefficient, offset 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; determine respective first signal phases corresponding to the microwave signal frequencies based on respective projection positions of the signal transmission correction coefficients in the 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 between the first signal phases, the total quality factor, the microwave signal frequencies and the first resonance frequency; perform phase fitting on the first signal phases corresponding to the microwave signal frequencies 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; perform fitting on the signal transmission coefficients based on the signal transmission parameter relationship, taking 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; perform fitting on respective signal transmission inverse coefficients corresponding to the signal transmission coefficients 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 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.

7. The apparatus of claim 6, wherein, The determination module is further configured to: obtain an initial transmission coefficient collected for the resonant cavity at the microwave signal frequency and a configured upper limit of a sampling number; 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 a smaller value between a sampling number matched with the signal-to-noise ratio and the upper limit of the sampling number as the sampling number at the microwave signal frequency.

8. The apparatus of claim 6, wherein, The processing module is further configured to: perform 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; 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 respective first coordinate information. 9.A computer device, comprising a memory and a processor, wherein the memory stores a computer program, and the computer device is configured to perform the method according to any one of claims 1-8 when the computer program is executed by the processor. The computer program is executed by the processor to implement the steps of the method of any one of claims 1 to 4.

10. A computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the steps of the method of any one of claims 1 to 4.

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