Self-adaptive tuning method for generating pulse-driven alternating-current quantum voltage

Abstract

The invention provides a self-adaptive tuning method for generating pulse-driven alternating-current quantum voltage, and aims to solve the problem that it is difficult to determine an optimal parameter combination in the quantum voltage generation process to achieve quantum working margin maximization. According to the method, a plurality of parameters are optimized through an automatic search algorithm, after optimization is completed, triangular waves are superposed at the bias end of a chip, and the working margin of pulse-driven alternating current quantum voltage is measured and evaluated, so that the optimal parameter setting capable of maximizing the working margin is determined. According to the method, the optimal system performance and stability can be provided in practical application, accurate control and optimization of the system performance are ensured through systematic data acquisition and analysis, and the optimal operation condition in a complex working environment is realized.

Description

Technical Field

[0001] The invention belongs to the field of metrology, and in particular relates to an adaptive tuning method for generating a pulse-driven alternating current quantum voltage. Background Art

[0002] The synthesis of pulse-driven AC quantum voltage can be achieved by driving the Josephson junction array with high-speed sequence pulses. The outstanding feature of this method is that the generated signal spectrum is pure and the bandwidth is wide, which makes it of great value in precision measurement and other applications that require extremely high signal purity and stability. However, in order to synthesize AC quantum voltage with pure spectrum, stable and accurate, extremely high requirements are placed on the quality of high-speed sequence pulses. The amplitude, frequency, and phase characteristics of the pulses must be precisely controlled to ensure that the Josephson junction array can be correctly driven and the required voltage signal can be generated. If the device parameters are slightly deviated, the synthesized AC quantum voltage signal may be distorted, noisy, or have other forms of errors, which directly affect the purity and stability of the signal. In addition, the synthesis system contains a large number of devices and multiple parameters to be adjusted, such as the timing control of the pulse generator, the electrical characteristics of the driving circuit and amplifier, and the working state of the Josephson junction array. The setting and adjustment of these parameters are crucial to the overall performance of the system. If a parameter is set improperly, it may cause instability of the high-speed sequence pulse, thereby affecting the quantum state of the voltage signal. This interference not only reduces the quality of the signal, but also may cause errors in measurement and standardization. Therefore, in order to ensure that the generated AC quantum voltage signal has the highest purity and accuracy, the generation process of high-speed sequence pulses must be precisely controlled. This involves careful optimization and calibration of each device and parameter in the synthesis system to ensure that they operate in the best state and avoid any potential interference or errors. Through this strict control and tuning, the advantages of pulse-driven AC quantum voltage technology can be maximized to provide high-precision voltage standards and signal sources. Summary of the invention

[0003] The present invention aims to solve the deficiencies in the prior art and proposes an adaptive tuning method for generating pulse-driven AC quantum voltage. The method optimizes multiple parameters through an automatic search algorithm. After the optimization is completed, a triangular wave is superimposed on the bias end of the chip, and the working margin of the pulse-driven AC quantum voltage is measured to determine the optimal parameter setting that can maximize the working margin. This method has excellent dynamics, intelligence and robustness. Its core lies in dynamically adjusting parameters based on real-time data and feedback information rather than relying on fixed preset values. This feature enables the system to flexibly respond to changes in the environment. Through the feedback control mechanism, the system can judge and adjust parameters in real time to ensure that the array is in the best working state.

[0004] The technical solution of the present invention is as follows:

[0005] Step 1: Use a radio frequency arbitrary waveform generator to generate an arbitrary waveform signal pulse train with specific amplitude and frequency to drive the synthesis system;

[0006] Step 2: According to the fundamental frequency of the AC quantum voltage signal to be synthesized, the sampling rate of the ADC sampler is determined, the spectrum of the measured signal is obtained, and its total harmonic distortion (THD) value is calculated;

[0007] Step 3: Use the automatic search algorithm based on the golden ratio, combined with the spectrum and THD results obtained in step 2, to gradually adjust the amplitude and phase of the pattern generator, the gain of the amplifier, and the amplitude and phase of the compensation circuit until the THD value is stable and the spectrum characteristics meet the expected requirements;

[0008] Step 4: After completing the parameter optimization, superimpose a triangular wave signal on the bias compensation end of the pulse-driven Josephson chip, and gradually increase the amplitude of the triangular wave until the background noise in the signal spectrum becomes larger, harmonics appear, and the THD value increases and is no longer stable. Based on the amplitude of the triangular wave at this time, the quantum working margin of the pulse-driven AC quantum voltage can be determined under the current parameter settings;

[0009] Step 5: Repeat steps 2 to 4 multiple times to construct a distribution curve of the relationship between the parameter to be adjusted and the quantum working margin of the pulse-driven AC quantum voltage, and finally determine the optimal parameter setting that can maximize the quantum working margin.

[0010] Specifically, the step 1 is implemented as follows:

[0011] A specific pulse train signal is generated by using an RF arbitrary waveform generator. The pulse train is configured to adapt to the specified amplitude and frequency arbitrary waveform according to the synthesis requirements. By precisely controlling the pulse amplitude and phase of the RF arbitrary waveform generator, a flexible and stable excitation source is provided for the pulse-driven AC quantum voltage synthesis system.

[0012] The step 2 is implemented as follows:

[0013] According to the fundamental frequency of the AC quantum voltage signal to be synthesized, the sampling rate of the sampler is determined.

[0014] The collected time domain data is converted into frequency domain information through Fourier transform to generate the spectrum of the measured signal. After obtaining the spectrum, the total harmonic distortion (THD) value of the signal is further calculated.

[0015] The step three is implemented as follows:

[0016] When using the automatic search algorithm based on the golden ratio for parameter optimization, the spectrum characteristics meet the expected requirements while ensuring that the THD value is stable at the minimum value; during initialization, define the search range of the device parameters to be adjusted, and use the golden ratio algorithm to search efficiently in the parameter space, by continuously adjusting the parameters, and obtaining the signal spectrum diagram and calculating the THD value after each adjustment. The algorithm iteratively narrows the search range to approach the optimal parameter setting. Each adjustment updates the search strategy based on the evaluation results of the THD value and the spectrum diagram to ensure that the THD value is minimized and the spectrum characteristics meet the expected requirements. When the THD value stabilizes at the lowest point and the spectrum characteristics meet the requirements, the optimization process ends.

[0017] The step 4 is implemented as follows:

[0018] After completing the parameter optimization, a triangular wave with increasing amplitude is gradually applied to the bias compensation end of the pulse-driven Josephson chip. As the amplitude of the triangular wave gradually increases, the system will experience different working states, eventually leading to the appearance of harmonics in the signal spectrum, that is, new frequency components appear in the spectrum.

[0019] During this process, the THD (total harmonic distortion) value will increase significantly and tend to be unstable. By accurately measuring and recording the amplitude of the triangle wave at this time, the quantum working margin of the pulse-driven AC quantum voltage can be determined under the current parameter settings. This margin represents the stability range of the system under working conditions and the maximum excitation intensity it can withstand.

[0020] The step five is achieved as follows:

[0021] After the system completes the initial optimization, steps 2 to 4 are repeated multiple times to establish a relationship distribution curve between the parameters to be adjusted and the quantum working margin of the pulse-driven AC quantum voltage. The specific operations include repeatedly adjusting the device parameters, reacquiring the signal spectrum, and calculating the THD value. During each adjustment process, the triangular wave signal is superimposed on the bias compensation end of the pulse-driven Josephson chip, and the amplitude of the triangular wave is gradually increased until a significant increase in harmonic phenomena and THD values ​​is observed.

[0022] By iterating this process multiple times, a series of experimental data between parameter configurations and quantum working margins are generated, and a relationship distribution curve between parameters and quantum working margins is drawn, which shows in detail the impact of different parameter settings on the system working margin. This relationship distribution curve not only reveals the specific impact of each parameter on system performance, but also helps identify the optimal parameter configuration, that is, the setting that can maximize the quantum working margin among all test parameters.

[0023] In summary, based on the analysis of the relationship distribution curve, the optimal parameter combination that can maximize the quantum working margin is determined. This optimal setting can provide the best system performance and stability in practical applications, and provides a scientific basis for the design and optimization of pulse-driven AC quantum voltage synthesis systems. This method ensures precise control and optimization of system performance through systematic data acquisition and analysis, and achieves optimal operating conditions in complex working environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Flowchart for realizing an adaptive tuning method for generating pulse-driven AC quantum voltage; DETAILED DESCRIPTION

[0025] The present invention will be further described below in conjunction with the accompanying drawings:

[0026] 1. Startup process

[0027] First, the system enters the startup phase of the parameter optimization process. At this point, it is necessary to select the key parameters to be adjusted from the system device parameters. These parameters include the pulse amplitude and phase of the RF arbitrary waveform generator in the system, the gain of the microwave amplifier, the amplitude and phase of the bias compensation voltage, which have a direct impact on the generation of pulse-driven AC quantum voltage. Selecting an appropriate parameter set is the first step in the optimization process, and its accuracy directly determines the efficiency and effectiveness of subsequent optimization steps.

[0028] A specific pulse train signal is generated by using an RF arbitrary waveform generator, which is configured as an arbitrary waveform with a specified amplitude and frequency according to the synthesis requirements. By precisely controlling the pulse amplitude and phase parameters of the RF arbitrary waveform generator, a flexible and stable excitation source is provided for the pulse-driven AC quantum voltage synthesis system.

[0029] 2. Spectrum analysis and THD calculation

[0030] After the parameters to be adjusted are selected, the pulse sequence generated by the system will be input into the ADC sampler, and the spectrum diagram of the signal will be obtained through spectrum analysis. This spectrum diagram reflects the distribution of each frequency component in the signal, especially the fundamental and harmonic waves. Next, the total harmonic distortion (THD) value is calculated. The THD value is an important indicator to measure the purity of the signal, which reflects the strength of the non-fundamental components in the signal. Through this step, the effect of the current parameter configuration can be evaluated, providing the necessary data support for subsequent optimization and adjustment.

[0031] Specifically, the sampling rate of the sampler is determined according to the fundamental frequency of the AC quantum voltage signal to be synthesized to ensure effective acquisition of the signal. The setting of the sampling rate is crucial. It must not only meet the requirements of the Nyquist sampling theorem to prevent signal aliasing, but also adapt to the specific frequency characteristics of the pulse sequence to capture complete signal information. In this way, the sampler can obtain the time domain data of the measured signal with sufficient resolution and accuracy.

[0032] The collected time domain data is converted into frequency domain information through Fourier transform to generate a spectrum diagram of the measured signal. This spectrum diagram shows in detail the distribution of each frequency component in the signal, especially the amplitude relationship between the fundamental wave and each harmonic. After obtaining the spectrum diagram, the total harmonic distortion of the signal is further calculated. By calculating THD, the degree of harmonic distortion in the signal can be quantified, which is of great significance for evaluating signal quality and system performance. A low THD value indicates that the signal is close to the ideal state and the harmonic distortion is small. Conversely, it means that there are more high-order harmonic components in the signal, which affects the overall stability and measurement accuracy of the system. Through this process, key spectrum data support can be provided for subsequent parameter optimization and system tuning.

[0033] 3. Automatic search algorithm based on the golden ratio

[0034] According to the spectrum and THD results obtained in step 2, the selected equipment parameters are optimized and adjusted using an automatic search algorithm based on the golden ratio. The golden ratio algorithm is an effective global optimization method that can find a near-optimal solution in the parameter space in a short time. In each iteration, the algorithm adjusts the search range of the parameters and updates their values ​​based on the feedback of the current spectrum and THD, gradually approaching the optimal parameter combination that minimizes the THD value and meets the requirements for spectrum characteristics. This process is repeated until the system performance indicators tend to stabilize.

[0035] Specifically, when using the automatic search algorithm based on the golden ratio for parameter optimization, it is necessary to first clarify the optimization goal, that is, to ensure that the THD value is stable at the minimum value while making the spectrum characteristics meet the expected requirements. During initialization, the search range of the device parameters to be adjusted is defined, and the golden ratio algorithm is used to search efficiently in the parameter space. By continuously adjusting the parameters, and obtaining the spectrum diagram of the signal and calculating the THD value after each adjustment, the effect of the current parameter setting is evaluated. The algorithm continuously narrows the search range in an iterative manner to approach the optimal parameter setting. Each adjustment updates the search strategy based on the evaluation results of the THD value and the spectrum diagram to ensure that the THD value is minimized and the spectrum characteristics meet the expected requirements. When the THD value stabilizes at the lowest point and the spectrum characteristics meet the requirements, the optimization process ends. Finally, these optimal parameter configurations are recorded and applied to improve the overall performance and stability of the system.

[0036] 4. Superimpose triangle waves and measure quantum working margin

[0037] After completing the above automatic search and optimization, a triangular wave signal is further superimposed on the bias compensation end of the pulse-driven Josephson chip. By gradually increasing the amplitude of the triangular wave, the response of the system is observed until harmonics appear in the signal spectrum and the THD value increases and is no longer stable. The quantum operating margin corresponding to the triangular wave amplitude at this time can be used to evaluate the effectiveness of the current parameter setting. Through this process, the operating limit and stability of the system under specific parameters can be determined.

[0038] Specifically, after completing the parameter optimization, a triangular wave signal is superimposed on the bias compensation end of the pulse-driven Josephson chip. At the beginning of this process, a triangular wave with increasing amplitude is gradually applied to observe its effect on the system response. As the amplitude of the triangular wave gradually increases, the system will experience different working states, eventually leading to the appearance of harmonics in the signal spectrum, that is, the appearance of new frequency components in the spectrum, which usually indicates that the working state of the system is close to its nonlinear or critical point.

[0039] During this process, the THD (total harmonic distortion) value will increase significantly and tend to be unstable, which reflects the enhancement of high-order harmonic components in the system, further verifying the occurrence of harmonic phenomena. By accurately measuring and recording the amplitude of the triangle wave at this time, the quantum working margin of the pulse-driven AC quantum voltage can be determined under the current parameter settings. This margin represents the stability range of the system under working conditions and the maximum excitation intensity it can withstand without causing signal distortion or performance degradation.

[0040] 5. Construct the distribution curve of parameters and quantum working margin

[0041] Repeat the process from step 2 to step 4 several times to obtain quantum working margin data under different parameter configurations. These data are sorted and analyzed to construct a distribution curve of the relationship between the parameters to be adjusted and the quantum working margin. This distribution curve shows the trend of the influence of parameter changes on the quantum working margin, helping to identify the parameter combination that maximizes the quantum working margin.

[0042] In the process of establishing the relationship distribution curve between the parameters to be adjusted and the quantum working margin of the pulse-driven AC quantum voltage, the specific operations include repeatedly adjusting the device parameters, reacquiring the spectrum of the signal, and calculating the THD value. During each adjustment process, the triangle wave signal is superimposed on the bias compensation end of the pulse-driven Josephson chip, and the amplitude of the triangle wave is gradually increased until the harmonic phenomenon and the THD value are observed. This process allows for a systematic evaluation of the quantum working margin under different parameter conditions.

[0043] By iterating this process multiple times, a series of experimental data between parameter configurations and quantum working margins can be generated. These data are used to draw a distribution curve between the parameters and the quantum working margin, which shows in detail the impact of different parameter settings on the system working margin. This relationship distribution curve not only reveals the specific impact of each parameter on system performance, but also helps identify the optimal parameter configuration, that is, the setting that can maximize the quantum working margin among all tested parameters.

[0044] 6. Finalize the optimal parameter settings

[0045] Through multiple iterations and analysis of the relationship distribution curve, the optimal parameter settings that can maximize the quantum working margin are finally determined. This stage marks the end of the entire optimization process. The system parameters have been adjusted to the best configuration, which can provide the highest stability and optimal performance in practical applications, and provide reliable support for the generation of pulse-driven AC quantum voltage systems.

Claims

1. An adaptive tuning method for generating a pulse-driven AC quantum voltage, characterized in that: The steps include: Step 1: Use a radio frequency arbitrary waveform generator to generate an arbitrary waveform signal pulse train with specific amplitude and frequency to drive the synthesis system; Step 2: According to the fundamental frequency of the AC quantum voltage signal to be synthesized, the sampling rate of the ADC sampler is determined, the spectrum of the measured signal is obtained, and its total harmonic distortion (THD) value is calculated; Step 3: Use the automatic search algorithm based on the golden ratio, combined with the spectrum and THD results obtained in step 2, to gradually adjust the amplitude and phase of the pattern generator, the gain of the amplifier, and the amplitude and phase of the compensation circuit until the THD value is stable and the spectrum characteristics meet the expected requirements; Step 4: After completing the parameter optimization, a triangular wave signal is superimposed on the bias compensation end of the pulse-driven Josephson chip, and the amplitude of the triangular wave is gradually increased until the background noise in the signal spectrum becomes larger, harmonics appear, and the THD value increases and is no longer stable; according to the amplitude of the triangular wave at this time, the quantum working margin of the pulse-driven AC quantum voltage under the current parameter setting can be determined; Step 5: Repeat steps 2 to 4 multiple times to construct a distribution curve of the relationship between the parameter to be adjusted and the quantum working margin of the pulse-driven AC quantum voltage, and finally determine the optimal parameter setting that can maximize the quantum working margin.

2. The adaptive tuning method for generating pulse-driven AC quantum voltage according to claim 1, characterized in that: The step 2 is specifically as follows: The sampling rate of the sampler is determined according to the fundamental frequency of the AC quantum voltage signal to be synthesized. The collected time domain data is converted into frequency domain information through Fourier transform to generate the spectrum of the measured signal. After obtaining the spectrum, the total harmonic distortion (THD) value of the signal is further calculated.

3. The adaptive tuning method for generating pulse-driven AC quantum voltage according to claim 1, characterized in that: Step three specifically includes: When using the automatic search algorithm based on the golden ratio for parameter optimization, the spectrum characteristics meet the expected requirements while ensuring that the THD value is stable at the minimum value. During initialization, the search range of the device parameters to be adjusted is defined, and the golden ratio algorithm is used to perform efficient search in the parameter space, and the parameters are continuously adjusted. After each adjustment, the spectrum diagram of the signal is obtained and the THD value is calculated. The algorithm iteratively narrows the search range to approach the optimal parameter setting. Each adjustment updates the search strategy based on the evaluation results of the THD value and the spectrum diagram to ensure that the THD value is minimized and the spectrum characteristics meet the expected requirements. When the THD value stabilizes at the lowest point and the spectrum characteristics meet the requirements, the optimization process ends.

4. The adaptive tuning method for generating pulse-driven AC quantum voltage according to claim 1, characterized in that: Step 4 in the formula specifically includes: After completing the parameter optimization, a triangle wave with increasing amplitude is gradually applied to the bias compensation end of the pulse-driven Josephson chip. As the amplitude of the triangle wave gradually increases, the system will experience different working states, which will eventually lead to the appearance of harmonics in the signal spectrum, that is, new frequency components appear in the spectrum. During this process, the THD value will increase significantly and tend to be unstable. By accurately measuring and recording the amplitude of the triangle wave at this time, the quantum working margin of the pulse-driven AC quantum voltage can be determined under the current parameter settings. This margin represents the stability range of the system under working conditions and the maximum excitation intensity it can withstand.

5. The adaptive tuning method for generating pulse-driven AC quantum voltage according to claim 1, characterized in that: Step 5 specifically includes: After the system completes the initial optimization, steps 2 to 4 are repeated multiple times to establish a relationship distribution curve between the parameters to be adjusted and the quantum working margin of the pulse-driven AC quantum voltage. The specific operations include repeatedly adjusting the device parameters, reacquiring the signal spectrum, and calculating the THD value. During each adjustment process, the triangular wave signal is superimposed on the bias compensation end of the pulse-driven Josephson chip, and the amplitude of the triangular wave is gradually increased until a significant increase in harmonic phenomena and THD values ​​is observed.

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