Method for determining probe frequency response calibration parameters, frequency response compensation method, measurement system and storage medium

Abstract

The application provides a probe frequency response calibration parameter determination method, a frequency response compensation method, a measurement system and a storage medium. The calibration parameter determination method comprises obtaining frequency response measurement data of a probe in a working frequency band, and determining a transition frequency point based on the frequency response measurement data; using the transition frequency point as a boundary, generating gain and phase calibration parameters in a first sub-frequency band below or equal to the transition frequency point by a first method, and generating gain and phase calibration parameters in a second sub-frequency band above the transition frequency point by a second method different from the first method. The compensation method selects a differentiated compensation strategy based on the relationship between the determined transition frequency point and the rated working frequency band of the probe, and accurately compensates the measured signal by using the corresponding probe calibration parameter and the oscilloscope channel calibration parameter of the selected strategy. The application realizes accurate and adaptive compensation of the probe in the full frequency band, and improves the accuracy and reliability of the measurement system.

Description

Technical Field

[0001] This application relates to the field of electronic measurement technology, specifically to a method for determining probe frequency response calibration parameters, a frequency response compensation method, a measurement system, and a storage medium. Background Technology

[0002] With the widespread application of 5G mobile communication, high-speed serial data interfaces, and millimeter-wave technology, the rate and frequency of the signals under test have entered the ultra-high frequency band of tens of GHz. Accurate measurements under such extreme conditions require a flat and predictable frequency response throughout the signal chain. As a key front-end component connecting the measured point to the oscilloscope input channel, the amplitude and phase frequency response characteristics of the oscilloscope probe have become the core factors restricting the measurement accuracy of the entire system.

[0003] Currently, the mainstream methods for obtaining probe frequency response calibration data mainly include the following categories: First, the "spot frequency" calibration method based on a standard signal source. This method involves inputting a DC or single-frequency sine wave signal of known amplitude to the probe and adjusting the probe hardware or oscilloscope software gain to match the readings. This method is usually only effective at a few frequency points. Second, the "system comparison" method based on swept-frequency signals and de-embedding calculations. This method uses an RF signal source and an oscilloscope to build a measurement system, acquiring frequency response data before and after the probe is connected to the system. The probe calibration data is obtained through mathematical operations (such as gain division and phase subtraction) to "de-embedding" the signal. Third, the direct measurement method based on a vector network analyzer (VNA). This method treats the probe as a two-port network and directly measures its S-parameters (such as S21) to obtain its transmission characteristics.

[0004] However, traditional point-frequency methods cannot obtain broadband continuous frequency responses. System comparison methods and direct VNA measurement methods are limited by the performance limits of the calibration system itself, and the accuracy and reliability of their calibration results are severely constrained by the performance boundaries of the calibration measurement system. When the calibration frequency approaches or exceeds the effective bandwidth of the oscilloscope or VNA used, the system's own noise increases and the response becomes distorted, leading to a deterioration in the signal-to-noise ratio and a decrease in accuracy of the acquired high-frequency calibration data. If this distorted data, which includes the system's own limitations, is stored in a fixed format, when the probe is connected to a higher-performance measurement system (such as a higher-bandwidth oscilloscope), the system will compensate based on these distorted parameters, thus introducing additional errors in the high-frequency band. In addition, the large amount of data obtained through direct VNA measurement also increases the pressure on system storage. It is evident that existing methods lack an effective mechanism to separate the probe's true characteristics from distorted data and to robustly process unreliable high-frequency data. They cannot resolve the "bandwidth mismatch" contradiction between calibration data and the system being used, making it difficult to guarantee the probe's measurement accuracy over a wide bandwidth, especially at high frequencies. Summary of the Invention

[0005] To address the aforementioned shortcomings of existing technologies, this application provides a method for determining probe frequency response calibration parameters, a frequency response compensation method, a measurement system, and a storage medium. The aim is to solve the technical problems of high-frequency data distortion caused by limitations in the bandwidth of the calibration system, and the inability of the resulting calibration parameters to adapt to different bandwidth measurement systems, leading to a decrease in high-frequency measurement accuracy.

[0006] In a first aspect, embodiments of this application provide a method for determining probe frequency response calibration parameters, including:

[0007] Acquire frequency response measurement data of the probe within its operating frequency band;

[0008] Based on the frequency response measurement data, determine the transition frequency point of the probe within the operating frequency band;

[0009] Within a first sub-frequency band below or equal to the transition frequency point, the frequency response calibration parameters of the probe are generated using a first method.

[0010] In the second sub-band above the transition frequency point, the frequency response calibration parameters of the probe are generated using a second method;

[0011] The first method and the second method are different, and the frequency response calibration parameters include gain calibration parameters and phase calibration parameters.

[0012] In some embodiments, determining the transition frequency point of the probe within the operating frequency band based on the frequency response measurement data includes:

[0013] Based on the frequency response measurement data, determine the amplitude frequency response curve and / or phase frequency response curve of the probe;

[0014] Based on the amplitude frequency response curve, identify the frequency point where the amplitude decays to a first preset threshold; and / or, based on the phase frequency response curve, identify the frequency point where the phase deviation reaches a second preset threshold.

[0015] The identified frequency point is determined as the transition frequency point.

[0016] In some embodiments, the second method of generating calibration parameters includes:

[0017] Obtain a dataset of complex transmission parameters measured from multiple probes of the same model;

[0018] The complex transmission parameter dataset is processed to obtain processed frequency response data;

[0019] Based on the portion of the processed frequency response data corresponding to the second sub-frequency band, calibration parameters are generated for the second sub-frequency band.

[0020] In some embodiments, the step of processing the complex transmission parameter dataset to obtain processed frequency response data includes:

[0021] The complex transmission parameter dataset is averaged and smoothed to obtain smoothed complex frequency response data;

[0022] The amplitude portion of the smoothed complex frequency response data is normalized and linearly transformed to obtain linear amplitude frequency response data.

[0023] Phase extraction is performed on the smoothed complex frequency response data to obtain phase frequency response data.

[0024] In some embodiments, generating calibration parameters for the second sub-frequency band based on the portion of the processed frequency response data corresponding to the second sub-frequency band includes:

[0025] The portion of the linear amplitude frequency response data corresponding to the second sub-band is fitted with a function, and the gain calibration parameters for each frequency point in the second sub-band are determined based on the fitting results.

[0026] A function is fitted to the portion of the phase frequency response data corresponding to the second sub-band, and the phase calibration parameters for each frequency point within the second sub-band are determined based on the fitting results.

[0027] In some embodiments, generating calibration parameters using the first method includes:

[0028] Obtain a reference frequency response dataset of the calibration system to the test signal when the probe is not connected;

[0029] Obtain the system frequency response dataset of the calibration system in response to the same test signal when the probe is connected;

[0030] De-embedding calculations are performed on the reference frequency response dataset and the system frequency response dataset to determine the frequency response calibration parameters of the probe;

[0031] The calibration system includes at least a signal generation unit for generating test signals and a measurement unit for measuring frequency response; the test signals cover the entire operating frequency band of the probe and include a first type of test signal for exciting steady-state amplitude response and a second type of test signal for exciting transient phase response.

[0032] In some embodiments, the acquisition of the reference frequency response dataset of the calibration system in response to the test signal when no probe is connected includes:

[0033] The signal generation unit is controlled to output the first type of test signal in sequence according to a preset frequency sequence, and the measurement unit synchronously measures the signal amplitude value corresponding to each frequency point to obtain the first set of amplitude measurement results.

[0034] The signal generation unit is controlled to output the second type of test signal, and the corresponding first time-domain waveform is captured by the measurement unit.

[0035] The acquisition of the system frequency response dataset of the calibration system in response to the same test signal when the probe is connected includes:

[0036] The signal generation unit is controlled to output the first type of test signal sequentially according to the same preset frequency sequence, and the measurement unit synchronously measures the signal amplitude value corresponding to each frequency point to obtain the second set of amplitude measurement results.

[0037] The signal generation unit is controlled to output the second type of test signal, and the corresponding second time-domain waveform is captured by the measurement unit.

[0038] In some embodiments, the method for determining the frequency response calibration parameters of the probe further includes:

[0039] Select any frequency point as the reference point;

[0040] Based on the signal amplitude value corresponding to the reference point, the first set of amplitude measurement results and the second set of amplitude measurement results are normalized respectively.

[0041] Generate the first amplitude frequency response array and the second amplitude frequency response array corresponding to each frequency point respectively;

[0042] Perform frequency domain transformation on the first time-domain waveform and the second time-domain waveform respectively;

[0043] Based on the transformation results, the first set of phase values ​​and the second set of phase values ​​corresponding to each frequency point are extracted to generate the first phase frequency response array and the second phase frequency response array.

[0044] In some embodiments, the step of performing de-embedding calculations on the reference frequency response dataset and the system frequency response dataset to determine the frequency response calibration parameters of the probe includes:

[0045] The amplitude frequency response data corresponding to each frequency point in the second amplitude frequency response array and the first amplitude frequency response array are divided to obtain the gain calibration parameter array of the probe corresponding to each frequency point.

[0046] The second phase frequency response array and the first phase frequency response array are subtracted element by element to obtain the phase calibration parameter array of the probe corresponding to each frequency point.

[0047] Secondly, embodiments of this application provide a frequency response compensation method applied to a measurement system including a probe and an oscilloscope, comprising:

[0048] The frequency response calibration parameters of the probe and the channel calibration parameters of the oscilloscope itself are obtained; wherein the frequency response calibration parameters of the probe are determined by the method for determining the frequency response calibration parameters of the probe as described in any embodiment of the first aspect, and include at least the probe gain calibration parameters, the probe phase calibration parameters, and the transition frequency point;

[0049] Based on the probe's operating frequency band and the transition frequency point, a compensation strategy is selected from multiple compensation strategies to compensate for the frequency response of the measured signal acquired through the probe.

[0050] Determine the corresponding probe frequency response calibration parameters based on the selected compensation strategy;

[0051] Based on the determined probe frequency response calibration parameters and channel frequency response calibration parameters, frequency response compensation is performed on the measured signal.

[0052] In some embodiments, the compensation strategy for selecting the frequency response compensation of the measured signal acquired by the probe from multiple compensation strategies based on the operating frequency band of the probe and the transition frequency point includes:

[0053] Determine the relationship between the highest frequency of the probe's operating frequency band and the transition frequency point;

[0054] When the highest frequency in the probe's operating frequency band is lower than or equal to the transition frequency point, the first compensation strategy is selected for frequency response compensation.

[0055] When the highest frequency in the probe's operating frequency band is higher than the transition frequency point, and the transition frequency point is determined based on the amplitude attenuation of the probe's amplitude frequency response curve, a second compensation strategy is selected for frequency response compensation.

[0056] In some embodiments, the first compensation strategy is to select gain compensation parameters and phase compensation parameters corresponding to the probe in all operating frequency bands, generated in a first manner, as probe frequency response calibration parameters for frequency response compensation.

[0057] The second compensation strategy involves selecting phase compensation parameters generated in the first manner corresponding to the probe in all operating frequency bands, gain compensation parameters generated in the first manner corresponding to the probe in the first sub-frequency band, and gain compensation parameters generated in the second manner corresponding to the probe in the second sub-frequency band, which together serve as probe frequency response calibration parameters for frequency response compensation.

[0058] In some embodiments, the compensation strategy for selecting the frequency response compensation of the measured signal acquired by the probe from multiple compensation strategies based on the operating frequency band of the probe and the transition frequency point further includes:

[0059] When the highest frequency in the probe's operating frequency band is higher than the transition frequency point, and the transition frequency point is determined based on the phase deviation of the probe's amplitude frequency response curve, a third compensation strategy is selected for frequency response compensation.

[0060] The third compensation strategy involves selecting gain compensation parameters and phase compensation parameters generated in the first manner corresponding to the probe in the first sub-frequency band, and gain compensation parameters and phase compensation parameters generated in the second manner corresponding to the probe in the second sub-frequency band, which are then used together as probe frequency response calibration parameters for frequency response compensation.

[0061] Thirdly, embodiments of this application provide a measurement system, including:

[0062] probe;

[0063] An oscilloscope is configured to acquire a set of probe frequency response calibration parameters determined by the method for determining probe frequency response calibration parameters as described in any embodiment of the first aspect, and its own channel calibration parameters, and to perform frequency response compensation on the measured signal acquired by the probe based on the set of probe frequency response calibration parameters and its own channel calibration parameters, using a frequency response compensation method as described in any embodiment of the second aspect.

[0064] Fourthly, embodiments of this application provide a computer-readable storage medium storing a computer-executable program or instructions. When executed by a processor, the computer-executable program or instructions are used to implement the method for determining probe frequency response calibration parameters as described in any embodiment of the first aspect, and / or the frequency response compensation method as described in any embodiment of the second aspect.

[0065] The method for determining probe frequency response calibration parameters provided in this application introduces the concept of a transition frequency point, dividing the entire operating frequency band of the probe into two sub-bands, high and low. In the low-frequency band, where the response is stable, a first method is used to generate frequency response calibration parameters; while in the high-frequency band, where the response is complex, a more targeted second method is used to generate the frequency response calibration, in order to better compensate for amplitude roll-off and phase distortion. This application solves the problem of measurement data distortion caused by system noise, impedance mismatch, or individual differences in the high-frequency band by adopting a differentiated calibration parameter determination strategy for the response characteristics of different frequency bands. It ensures the accuracy of low-frequency band calibration while improving the stability and reproducibility of high-frequency band calibration parameters, ultimately obtaining a set of gain and phase calibration parameters that comprehensively and accurately reflect the probe's own frequency response characteristics, providing a reliable data foundation for subsequent accurate frequency response compensation of the probe across the entire frequency band.

[0066] The frequency response compensation method and measurement system provided in this application firstly determine the probe frequency response calibration parameters based on the method for determining probe frequency response calibration parameters provided in the above embodiments. Based on this, the complexity of the response characteristics is determined using the transition frequency points explicitly identified in the probe calibration parameters, combined with the probe's own rated bandwidth range: when the rated bandwidth is entirely within the low-frequency stable region, a unified and efficient compensation strategy is adopted to minimize resource consumption; when the rated bandwidth crosses the transition point determined by amplitude attenuation, segmented fine compensation is performed on the amplitude response to maintain the consistency of phase compensation; when the rated bandwidth crosses the transition point determined by phase deviation, segmented high-precision compensation is performed on both amplitude and phase. This multi-strategy compensation architecture not only ensures that the probe obtains accurate correction matching its response characteristics across the entire rated frequency band, but also effectively avoids computational redundancy caused by excessive use of complex algorithms in simple frequency bands. Simultaneously, the dedicated response to phase inflection points significantly improves the fidelity of broadband signal measurements.

[0067] In addition, this application also provides a computer-readable storage medium that has the same beneficial effects as the above-described method for determining probe frequency response calibration parameters and frequency response compensation method. Attached Figure Description

[0068] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0069] Figure 1 This is a schematic diagram of the structure of a measurement system provided in one embodiment of this application.

[0070] Figure 2 This is a flowchart illustrating a method for determining probe frequency response calibration parameters according to one embodiment of this application.

[0071] Figure 3 A flowchart illustrating a method for determining probe frequency response calibration parameters according to another embodiment of this application.

[0072] Figure 4 This is a schematic diagram of the structure of a calibration system provided in one embodiment of this application.

[0073] Figure 5 A flowchart illustrating a method for determining probe frequency response calibration parameters according to another embodiment of this application.

[0074] Figure 6 A flowchart illustrating a method for determining probe frequency response calibration parameters according to another embodiment of this application.

[0075] Figure 7 This is a flowchart of a frequency response compensation method provided in one embodiment of this application.

[0076] Figure 8 A flowchart of a frequency response compensation method provided in another embodiment of this application.

[0077] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0078] The present application will now be described in further detail with reference to the accompanying drawings and specific embodiments. Similar elements in different embodiments are referred to by related similar element reference numerals. In the following embodiments, many details are described to facilitate a better understanding of the present application. However, those skilled in the art will readily recognize that some features may be omitted in different situations, or may be replaced by other elements, materials, or methods. In some cases, certain operations related to the present application are not shown or described in the specification. This is to avoid obscuring the core parts of the present application with excessive description. For those skilled in the art, detailed description of these related operations is not necessary; they can fully understand the related operations based on the description in the specification and general technical knowledge in the art.

[0079] Furthermore, the features, operations, or characteristics described in the specification can be combined in any suitable manner to form various embodiments. At the same time, the steps or actions in the method description can be rearranged or adjusted in a manner obvious to those skilled in the art. Therefore, the various orders in the specification and drawings are only for the clear description of a particular embodiment and do not imply a necessary order, unless otherwise stated that a particular order must be followed.

[0080] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class, without limiting the number of objects; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship. Unless otherwise specified, the terms "connection" and "linkage" used in this application include both direct and indirect connections (linkages).

[0081] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0082] Figure 1 This is a schematic diagram of the structure of a measurement system provided in one embodiment of this application. Figure 1 As shown, the measurement system provided in this embodiment includes at least a matching probe 10 and an oscilloscope 20.

[0083] In this embodiment, probe 10 is the signal pickup and conditioning front end of the measurement system. Its core function is to transmit the electrical signal in the circuit under test to the oscilloscope 20 with the highest possible fidelity, and at the same time match the high impedance test point with the input impedance of the oscilloscope 20 to reduce the load effect on the original signal. Depending on the measurement requirements, probe 10 can be divided into various types such as passive voltage probe, active differential probe, and current probe. Its attenuation ratio, bandwidth and input impedance directly determine the range and accuracy of the signal that can be accurately measured.

[0084] The oscilloscope 20 is the core of the measurement system for display and analysis. It is essentially a graphical electronic measuring instrument that converts the amplitude of the acquired electrical signal over time into a visual waveform image displayed on the screen. This allows users to intuitively observe key parameters such as the waveform shape, amplitude, frequency, and phase of the signal, and to use its triggering, measurement, and mathematical calculation functions to perform in-depth analysis and fault diagnosis of the signal.

[0085] In actual measurements, it was found that when probe 10 is connected to the signal test point, it essentially constitutes an additional load on the signal path. This load effect will change the original signal characteristics at the test point. At the same time, the frequency response characteristics of the internal circuit of probe 10 are not ideally flat within its operating frequency band, which will introduce additional amplitude and phase errors. Therefore, before using this measurement system, the frequency response of probe 10 needs to be calibrated, that is, to compensate for the mismatch between probe 10 and the input channel of oscilloscope 20 and the difference in attenuation characteristics of probe 10 at different frequencies.

[0086] However, determining the probe's frequency response calibration parameters directly determines whether the entire measurement system can maintain signal amplitude consistency and phase linearity at different frequencies. If the parameters are set improperly, capacitive load mismatch between the input channels of probe 10 and oscilloscope 20 can lead to attenuation or enhancement of high-frequency components, resulting in amplitude deviation, blunted edges, or even ringing distortion in the observed waveform. Only when the calibration parameters are accurate can it be ensured that all frequency components of the signal can be transmitted without loss within the entire frequency spectrum of the probe 10's bandwidth limit, thereby guaranteeing that the measurement results truly reflect the high-frequency transient changes and low-frequency envelope characteristics of the measured point.

[0087] Therefore, the oscilloscope 20 is also configured to acquire probe frequency response calibration parameters when probe 10 is connected, and to use the probe frequency response calibration parameters to perform frequency response compensation on the measured signal acquired through probe 10.

[0088] In this embodiment, the probe frequency response calibration parameters reflect its attenuation and phase change patterns across the entire frequency band. During actual measurement, the oscilloscope 20 utilizes these pre-acquired parameters to perform digital signal processing on the measured signal acquired and transmitted in real time by the probe 10. Specifically, it uses inverse filtering or equalization algorithms to specifically compensate for the amplitude distortion and phase shift introduced by the probe 10 at different frequency points. Compared to traditional methods relying solely on hardware compensation, this approach can more accurately restore the true nature of the signal. Especially for signals with complex high-frequency components or those exhibiting distortion, it can significantly improve the fidelity of the entire measurement chain, ensuring that the final displayed waveform is an accurate mathematical reconstruction of the original state of the measured point.

[0089] The following section will further detail the method for determining the probe frequency response calibration parameters and the specific implementation process of oscilloscope 20 using the determined probe frequency response calibration parameters to achieve frequency response compensation. This process aims to accurately quantify the transmission characteristics of probe 10 across the entire frequency band through standardized excitation signal injection and response analysis.

[0090] Figure 2 This is a flowchart illustrating a method for determining probe frequency response calibration parameters according to one embodiment of this application. Figure 2As shown, the method for determining the probe frequency response calibration parameters provided in this embodiment can be applied to various types of probes. The parameter determination process specifically includes the following steps:

[0091] Step S210: Obtain the frequency response measurement data of the probe within the operating frequency band.

[0092] Before calibration begins, probe 10 must be used as the test object. Raw performance data of probe 10 within its specified operating frequency range must be obtained through measurement methods. This data includes the complete frequency response information of probe 10 from its lowest to its highest operating frequency. Specifically, an excitation signal with known characteristics (such as a swept-frequency sine wave) is input to probe 10, and the output response of probe 10 at different frequency points is precisely recorded, thus obtaining a raw dataset of the complete frequency response, including amplitude variation (gain) and phase shift. This measurement data can be obtained using a vector network analyzer, a swept-frequency signal source in conjunction with an oscilloscope 20, or other measurement equipment, covering complex transmission parameters (such as S21) or amplitude / phase response of probe 10's nominal operating frequency band.

[0093] Step S220: Determine the transition frequency point of the probe within the operating frequency band based on the frequency response measurement data.

[0094] Because the frequency response characteristics of probe 10 may exhibit different patterns in different frequency bands—for example, the response is relatively smooth and the measurement data is reliable in the low-frequency band, while in the high-frequency band, significant fluctuations or attenuation may occur due to system noise, impedance mismatch, or the characteristics of probe 10 itself—a transition frequency point is introduced to make the frequency response compensation of the measured signal based on the frequency response calibration parameters of probe 10 more accurate. This rationally divides the entire operating frequency band of probe 10 into two sub-regions with different response characteristics, providing a basis for subsequent differentiated processing strategies. The transition frequency point, or frequency boundary point, is typically the turning point where the response characteristics of probe 10 change significantly. This is achieved by analyzing the changing trends of amplitude or phase response, such as the point where the amplitude attenuates to a preset threshold or the phase deviation reaches a critical value.

[0095] Step S230: In the first sub-band below or equal to the transition frequency point, generate the probe's frequency response calibration parameters using the first method.

[0096] Step S240: In the second sub-band above the transition frequency point, generate the probe's frequency response calibration parameters using a second method; wherein the first method and the second method are different, and the frequency response calibration parameters include gain calibration parameters and phase calibration parameters.

[0097] After determining the transition frequency point, the entire operating frequency band of probe 10 is reasonably divided into two sub-regions with different response characteristics based on this transition frequency point. In the first sub-band, that is, the low-frequency band below the transition frequency point, probe 10 usually has good linearity and measurement signal-to-noise ratio, and the frequency response curve is relatively smooth; while in the second sub-band, that is, the high-frequency band above the transition frequency point, the response of probe 10 becomes more complex, and the measurement data is often affected by factors such as system bandwidth limitation, noise enhancement, and individual differences of probe 10, resulting in unstable or distorted direct measurement results.

[0098] In this embodiment, two different calibration parameter determination methods are employed for two sub-bands with different performance characteristics. In the low-frequency band below the transition frequency point (i.e., the first sub-band), a specific and generally simpler and more efficient method (the first method) is used to generate calibration parameters. The first method can be based on direct tabular interpolation of measurement data, de-embedding calculation based on comparative measurements before and after probe 10 is connected to the measurement system, or other high-precision parameter extraction methods suitable for the low-frequency band. Using the first method, the gain and phase calibration parameters corresponding to each frequency point within this sub-band can be obtained, ensuring the accuracy of low-frequency band compensation. In the high-frequency band above the transition frequency point (i.e., the second sub-band), using the same first method as the low-frequency band might introduce significant errors. Therefore, a second method, different from the first method, is chosen to generate calibration parameters. The second method can be a more refined point-by-point calibration, piecewise fitting using higher-order complex functions, or the introduction of a specific equalization algorithm to accurately correct complex amplitude and phase distortions within the high-frequency band.

[0099] This embodiment identifies a "transition frequency point," dividing the operating frequency band of probe 10 into two. A "divide and conquer" strategy is employed in each of the two sub-bands with different response characteristics, applying the most suitable calibration algorithm to each. This optimizes computational efficiency and implementation flexibility while ensuring calibration accuracy. The first method focuses on direct de-embedding through comparative measurements, suitable for low-frequency bands with high signal-to-noise ratios and stable responses. The second method focuses on statistical and fitting processing, suitable for high-frequency bands with large data fluctuations and significant individual differences. Regardless of the method used, the generated frequency response calibration parameters simultaneously include gain calibration parameters and phase calibration parameters, ensuring comprehensive correction of amplitude and phase distortion introduced by probe 10 during compensation.

[0100] In summary, the method for determining probe frequency response calibration parameters provided in this embodiment introduces the concept of a transition frequency point, dividing the entire operating frequency band of the probe into two sub-bands, high and low. In the stable low-frequency band, a simple and efficient first method is used to generate parameters, reducing computational overhead and avoiding overfitting. In the complex high-frequency band, a more targeted second method is used for precise calibration to better compensate for amplitude roll-off and phase distortion. By employing differentiated calibration parameter determination strategies for the response characteristics of different frequency bands, the problem of measurement data distortion caused by system noise, impedance mismatch, or individual differences in the high-frequency band by traditional methods is solved. This ensures the accuracy of low-frequency band calibration while improving the stability and reproducibility of high-frequency band calibration parameters. Ultimately, a set of gain and phase calibration parameters that comprehensively and accurately reflects the probe's own frequency response characteristics is obtained, providing a reliable data foundation for subsequent accurate frequency response compensation of the probe across the entire frequency band.

[0101] Figure 3 A flowchart illustrating a method for determining probe frequency response calibration parameters according to another embodiment of this application. Figure 3 As shown in the above embodiment, step S220, determining the transition frequency point of the probe within the operating frequency band based on the frequency response measurement data, specifically includes the following steps:

[0102] Step S2201: Based on the frequency response measurement data, determine the amplitude frequency response curve and / or phase frequency response curve of the probe.

[0103] Before determining the transition frequency point of probe 10 within its operating frequency band, the acquired raw frequency response measurement data needs to be processed to extract the relationship between amplitude and frequency. Specifically, this can be achieved through mathematical transformations or graphical processing to read the signal amplitude values ​​corresponding to each frequency point in the measurement data, constructing an amplitude-frequency response curve to describe the gain variation of probe 10 at different frequencies; and extracting the phase values ​​corresponding to each frequency point in the measurement data to construct a phase-frequency response curve to describe the phase delay characteristics of probe 10 at different frequencies. By converting the discrete frequency response measurement results into continuous characteristic curves that can intuitively reflect the performance of probe 10, the subsequent analysis and determination of the transition frequency point is facilitated. In practice, depending on the needs, only the amplitude curve, only the phase curve, or both can be determined, depending on the characteristics of probe 10 of interest and the requirements of subsequent compensation strategies.

[0104] Step S2202: Based on the amplitude frequency response curve, identify the frequency point corresponding to the amplitude attenuation to the first preset threshold; and / or, based on the phase frequency response curve, identify the frequency point corresponding to the phase deviation reaching the second preset threshold.

[0105] For the amplitude curve, when the frequency rises to a certain critical point, the gain of probe 10 may begin to decrease significantly, such as by 3dB, 1dB, or other preset attenuation amounts. This critical point often indicates that probe 10 has entered the high-frequency unstable region or the measurement system's signal-to-noise ratio has deteriorated. By setting a first preset threshold (such as -3dB), the corresponding frequency point can be identified from the amplitude curve. For the phase curve, when the frequency rises to a certain critical point, the phase response may exhibit nonlinear deviations, such as deviating from the linear phase by a preset angle (such as 5°, 10°, etc.). This critical point can also serve as a basis for distinguishing between the linear and nonlinear regions of probe 10. By setting a second preset threshold, the corresponding frequency point can be identified from the phase curve. By flexibly selecting amplitude thresholds, phase thresholds, or a combination of both, the critical position where the response characteristics undergo a qualitative change can be accurately captured according to different probe 10 types and calibration requirements.

[0106] Step S2203: Determine the identified frequency points as transition frequency points.

[0107] The frequency point defined in step S2202, whether it is the attenuation frequency point identified by the amplitude-frequency curve, the deviation frequency point identified by the phase-frequency curve, or the frequency point selected by a comprehensive consideration of both, is defined as the transition frequency point. This transition frequency point divides the entire operating frequency band of the probe 10 into two sub-bands with different characteristics: a first sub-band below or equal to this point, and a second sub-band above this point. The physical significance of the transition frequency point is that it is the dividing point where the frequency response characteristics of the probe 10 transition from the "measurable and reliable region" to the "unmeasurable or distorted region," or the dividing point where the performance of the measurement system transitions from the "effective region" to the "limited region." The determination of this point provides a clear frequency domain boundary basis for steps S230 and S240 to process the low-frequency and high-frequency bands respectively using different methods (the first method and the second method), and is the core foundation of the segmented calibration strategy.

[0108] The first method of generating the frequency response calibration parameters of probe 10 requires the use of a calibration system. By acquiring the frequency response data of probe 10 before and after it is connected to the calibration system, the two sets of data are processed to accurately extract the frequency response of probe 10 itself, thereby determining the calibration parameters that can be used for subsequent signal compensation.

[0109] Figure 4 This is a schematic diagram of the structure of a calibration system provided in one embodiment of this application. Figure 4 As shown, the calibration system provided in this embodiment includes a host computer 410, a signal generation unit 420, and a measurement unit 430.

[0110] In this embodiment, the host computer 410 serves as the control core and data processing center of the entire process, and is responsible for sending synchronization commands to the signal generation unit 420 and the measurement unit 430 to coordinate the precise execution of the calibration steps.

[0111] The signal generation unit 420 acts as the excitation source. Its core function is to generate test signals covering the entire operating frequency band of the probe 10 under the control of the host computer 410. This unit can generate at least two types of standard signals: one type is the first type of test signal, such as the swept sine wave used to excite the steady-state amplitude response, and the other type is the second type of test signal, such as the fast-edge pulse used to excite the transient phase response. This ensures that the response characteristics of the probe 10 can be fully excited at different frequency points and under dynamic conditions, providing a complete excitation basis for subsequent frequency response analysis.

[0112] The measurement unit 430 is responsible for capturing the signal transmitted by the probe 10 with high precision and completing the preliminary extraction of frequency response data. When the probe 10 is not connected, it directly collects the test signal generated by the signal generation unit 420 to establish a reference frequency response dataset. After the probe 10 is connected, it synchronously collects the same test signal after passing through the probe 10 to construct a system frequency response dataset.

[0113] During the determination of the frequency response calibration parameters of probe 10, probe 10 is physically connected in series to the signal link. Specifically, its signal input is connected to the signal generation unit 420 to receive standard test excitation, while its signal output is connected to the input channel of the measurement unit 430, thus forming a complete signal transmission path. At this time, probe 10, as the object under test, is positioned between the signal generation unit 420 and the measurement unit 430. This means that the test signal must pass through the attenuation network, transmission cable, and compensation circuit inside probe 10 before being captured by the measurement unit 430. This connection method ensures that the data acquired by the measurement unit 430 truly incorporates all the influence of probe 10 on the signal amplitude and phase.

[0114] In some embodiments, the signal generation unit 420 includes a radio frequency signal source and a fast-edge pulse generator. The radio frequency signal source is used to output a frequency scanning sine wave signal covering the entire operating frequency band of the probe 10 as a first type of test signal; the fast-edge pulse generator is used to output a fast-edge pulse signal covering the entire operating frequency band of the probe 10 as a second type of test signal.

[0115] The signal generation unit 420 is designed to include two excitation sources: an RF signal source and a fast-edge pulse generator, to provide two types of test signals for steady-state analysis and transient analysis, respectively. The RF signal source outputs a continuously adjustable or stepped sweep sine wave as the first type of test signal. Its core function is to accurately measure the steady-state amplitude response (gain / attenuation) of the probe 10 at discrete frequency points by traversing the entire nominal operating frequency band of the probe 10. The fast-edge pulse generator outputs a pulse signal with an extremely fast rise time (theoretically covering an extremely wide spectrum) as the second type of test signal. Its function is to use the rich frequency components in the pulse to excite the full-band response of the probe 10 at once, which is particularly suitable for capturing the phase characteristics of the probe 10 under transient conditions. By integrating these two signal generators into the same unit, the calibration system can simultaneously acquire complete response data of the probe 10 in both the frequency domain (steady-state) and time domain (transient), providing complementary and mutually verifying raw datasets for subsequent de-embedding calculations, thereby ensuring that the determined frequency response calibration parameters have both amplitude accuracy and phase accuracy.

[0116] In some embodiments, the measurement unit 430 is a high-bandwidth oscilloscope 20, which can convert the acquired time-domain waveform into frequency-domain data containing amplitude and phase information of multiple frequency points through Fourier transform, and upload this data to the host computer 410 for subsequent processing.

[0117] Meanwhile, the host computer 410 is also responsible for receiving the raw sampling data returned by the measurement unit 430, running the pre-stored algorithm to perform complex frequency domain vector calculation on the reference frequency response dataset and the system frequency response dataset, thereby extracting the frequency response calibration parameters of the probe 10, and storing or writing the final parameters back into the storage chip of the probe 10 to provide accurate compensation basis for the measurement system.

[0118] In some embodiments, the signal generation unit 420 and the measurement unit 430 are connected by a coaxial cable 440 and a fixture 450.

[0119] To achieve a stable and repeatable RF connection, a basic signal link is established between the signal generation unit 420 and the measurement unit 430 via a coaxial cable 440 and a fixture 450. During the determination of calibration parameters, the probe 10 is connected between the output of the fixture 450 and the input of the measurement unit 430: the test signal emitted by the signal generation unit 420 is first transmitted to the fixture 450 via the coaxial cable 440, and then fed into the signal input of the probe 10 by the fixture 450, while the signal output of the probe 10 is directly connected to the measurement unit 430. This connection method makes the parasitic parameters and contact impedance introduced by the fixture 450 part of the system frequency response dataset, thereby ensuring that the probe frequency response calibration parameters extracted through de-embedding calculation more closely reflect its actual performance in real-world applications.

[0120] Figure 5 A flowchart illustrating a method for determining probe frequency response calibration parameters according to another embodiment of this application. Figure 5 As shown, based on Figure 4 The calibration system shown above, in step S230 of the above embodiment, generates the frequency response calibration parameters of the probe using a first method within the first sub-frequency band below or equal to the transition frequency point, specifically includes the following steps:

[0121] Step S2301: Obtain the reference frequency response dataset of the calibration system's response to the test signal when the probe is not connected. The test signal covers the entire operating frequency band of the probe, including a first type of test signal used to excite the steady-state amplitude response and a second type of test signal used to excite the transient phase response.

[0122] The purpose of acquiring a reference frequency response dataset of the calibration system's response to the test signal when probe 10 is not connected is to establish a reference benchmark for the entire measurement link (excluding probe 10 under test) itself, thereby eliminating the influence of potential non-ideal amplitude and phase frequency characteristics of the signal source, connecting cables, and the input channel of the oscilloscope 20 on subsequent calibration results. After the calibration system is set up, the host computer 410 controls the signal generation unit 420 to output a test signal covering the entire operating frequency band of probe 10. This signal includes a first type of test signal for exciting the steady-state amplitude response and a second type of test signal for exciting the transient phase response. At this time, probe 10 is not yet connected to the link, and the test signal is directly transmitted to the measurement unit 430 through the coaxial cable 440 and the fixture 450. The measurement unit 430 performs high-precision acquisition and frequency domain transformation processing on the signal, ultimately obtaining a reference frequency response dataset containing amplitude and phase information corresponding to multiple frequency points.

[0123] Step S2302: Obtain the system frequency response dataset of the calibration system when the probe is connected to the same test signal.

[0124] After obtaining the reference frequency response dataset for the test signal response, while keeping the output settings of the signal generation unit 420 completely consistent with step S2301, the probe 10 is connected to the link. That is, the input end of the probe 10 is connected to the output port of the fixture 450, and the output end is connected to the input channel of the measurement unit 430 to obtain the comprehensive frequency response characteristics of the complete transmission path including the probe 10. After the probe 10 is connected, the test signal must pass through the front-end attenuation network, transmission cable, and compensation circuit inside the probe 10 before it can be captured by the measurement unit 430. The signal generation unit is controlled to output the exact same test signal again, and the measurement unit 430 performs synchronous sampling and frequency domain analysis on the signal transmitted through the probe 10 again to generate the system frequency response dataset. Since the probe 10 itself introduces specific amplitude attenuation, frequency selectivity characteristics, and phase delay, this dataset essentially integrates the total effect of the probe 10 and the back-end measurement link. After comparison and processing with the reference frequency response dataset, the frequency response characteristics of the probe 10 can be separated.

[0125] Step S2303: Perform de-embedding calculations on the reference frequency response dataset and the system frequency response dataset to determine the frequency response calibration parameters of the probe.

[0126] After obtaining the reference frequency response dataset and system frequency response dataset before and after probe 10 is connected to the calibration system, mathematical stripping technology is used to perform de-embedding calculation on the reference frequency response dataset and system frequency response dataset. From the system frequency response data that incorporates the influence of probe 10, the link background characteristics represented by the reference frequency response dataset are accurately removed, thereby accurately extracting the independent frequency response characteristics of probe 10 itself.

[0127] Specifically, the de-embedding computation processes the corresponding frequency points of the two datasets separately in the complex frequency domain: for amplitude frequency response data, a division operation is used to divide the amplitude values ​​in the system frequency response dataset point by point by the corresponding amplitude values ​​in the reference frequency response dataset, thereby eliminating amplitude deviations caused by factors such as signal source unevenness, cable loss, and the gain of the 430-channel measurement unit; for phase frequency response data, a subtraction operation is used to subtract the corresponding phase values ​​in the reference frequency response dataset point by point from the phase values ​​in the system frequency response dataset, thereby removing the phase offset introduced by link attachments. Through this joint vector operation of amplitude division and phase subtraction, the finally calculated pure data is the frequency response calibration parameter of probe 10. It accurately quantifies the actual gain / attenuation characteristics and phase change characteristics of probe 10 at each frequency point in the entire operating frequency band, providing a calibration compensation basis for the subsequent accurate amplitude restoration and phase compensation of the measured signal by the oscilloscope 20.

[0128] In some embodiments, step S2301, obtaining the reference frequency response dataset of the calibration system's response to the test signal when no probe is connected, specifically includes:

[0129] The control signal generation unit outputs the first type of test signal in sequence according to the preset frequency sequence, and the measurement unit synchronously measures the signal amplitude value corresponding to each frequency point to obtain the first set of amplitude measurement results.

[0130] Additionally, the control signal generation unit outputs a second type of test signal and captures the corresponding first time-domain waveform through the measurement unit.

[0131] With the calibration system not connected to probe 10, the control signal generation unit outputs a first-type test signal (such as a swept-frequency sine wave signal used to excite the steady-state amplitude response) sequentially in a step-by-step manner according to a preset frequency sequence covering the entire operating frequency band of probe 10. The measurement unit synchronously measures the amplitude of the system (excluding probe 10) at each frequency point, recording the response amplitude value at each frequency point, forming the first set of amplitude measurement results. This set of data reflects the gain characteristics of the signal generation unit, the measurement unit, and the transmission path between them throughout the entire operating frequency band, serving as a reference for separating the amplitude response of probe 10 in subsequent de-embedding calculations. The density of the preset frequency sequence determines the frequency resolution of the calibration, and synchronous measurement ensures accurate correspondence of data at each frequency point.

[0132] Then, the control signal generation unit outputs a second type of test signal (such as a broadband fast-edge pulse signal used to excite the transient phase response). The measurement unit captures the complete time-domain waveform of this signal after it passes through the system at a high sampling rate, which is used as the first time-domain waveform. Since the fast-edge pulse signal contains rich frequency components, the phase response characteristics of the system throughout the entire operating frequency band can be extracted by performing a frequency domain transformation (such as a Fourier transform) on this time-domain waveform. The first time-domain waveform records the phase reference information of the system without probe 10, which serves as the reference for separating the phase response of probe 10 in subsequent de-embedding calculations.

[0133] In some embodiments, step S2302, obtaining the system frequency response dataset of the calibration system responding to the same test signal when the probe is connected, specifically includes:

[0134] The control signal generation unit outputs the first type of test signal in sequence according to the same preset frequency sequence, and the measurement unit synchronously measures the signal amplitude value corresponding to each frequency point to obtain the second set of amplitude measurement results.

[0135] Additionally, the control signal generation unit outputs a second type of test signal and captures the corresponding second time-domain waveform through the measurement unit.

[0136] With probe 10 connected between the signal generation unit and the measurement unit, the signal generation unit is again controlled to output the first type of test signal sequentially according to the same preset frequency sequence as in the previous steps. The measurement unit simultaneously measures the signal amplitude value corresponding to each frequency point, forming the second set of amplitude measurement results. The data acquired at this time is the overall amplitude response of "probe + system", that is, the superposition of the amplitude characteristics of probe 10 and the reference amplitude characteristics of the system. By maintaining completely consistent test conditions and frequency sequences, it is ensured that the second set of amplitude measurement results has a one-to-one comparability with the first set of amplitude measurement results, which is the basis for subsequent separation of the amplitude characteristics of probe 10 through de-embedding operations.

[0137] Then, the signal generation unit outputs the exact same second type of test signal (fast-edge pulse), and the measurement unit captures the time-domain waveform of the signal after passing through the "probe + system," which serves as the second time-domain waveform. This waveform contains comprehensive information about the phase characteristics of probe 10 and the system's reference phase characteristics. By comparing and analyzing this waveform with the acquired first time-domain waveform (after frequency domain transformation), the phase response of probe 10 itself can be separated. Maintaining identical signal type and measurement conditions ensures the comparability of the two captured time-domain waveforms, which is the basis for subsequent separation of probe 10's phase characteristics through de-embedding operations.

[0138] In some embodiments, step S2303, performing de-embedding calculations on the reference frequency response dataset and the system frequency response dataset to determine the probe's frequency response calibration parameters, specifically includes:

[0139] Specifically, the amplitude-frequency response includes:

[0140] Select any frequency point as a reference point; based on the signal amplitude value corresponding to the reference point, normalize the first group of amplitude measurement results and the second group of amplitude measurement results respectively; then generate the first amplitude frequency response array and the second amplitude frequency response array corresponding to each frequency point respectively; and perform division operation on the amplitude frequency response data corresponding to each frequency point in the second amplitude frequency response array and the first amplitude frequency response array respectively to obtain the gain calibration parameter array of the probe 10 corresponding to each frequency point.

[0141] To eliminate the influence of the absolute amplitude of the test signal and the absolute gain of the measurement unit 430 on subsequent calculations, and to ensure that the calibration results only focus on the relative amplitude changes of the probe 10 at various frequency points, data processing of the measurement results is required. Specifically, the amplitude value of a certain frequency point (such as 1kHz or the center point of the probe 10's operating frequency band) is selected from the first set of measurement results as a reference value. Then, the measured values ​​of all frequency points in this set are divided by this reference value to obtain the normalized first amplitude sequence. Similarly, the amplitude value of the same frequency point as the first set of measurement results is selected from the second set of measurement results as a reference, and the same normalization operation is performed. Through normalization, both sets of data are converted into relative amplitude values ​​with the reference point as the 0dB reference.

[0142] After normalization, the normalized data is organized and structured according to frequency points, forming two standard array formats. The first amplitude-frequency response array represents the relative amplitude-frequency characteristics of the measurement link itself without probe 10; the second amplitude-frequency response array represents the relative amplitude-frequency characteristics of the entire system including probe 10.

[0143] After obtaining the frequency response arrays characterizing the relative amplitude-frequency characteristics of the system link before and after the probe 10 is connected, since the second amplitude-frequency response array includes the total effect of the probe 10 and the link, while the first amplitude-frequency response array only represents the effect of the link itself, the gain contribution of the probe 10 itself can be accurately extracted from the total effect by dividing the amplitude value of the second amplitude-frequency response array by the corresponding amplitude value of the first amplitude-frequency response array at each frequency point. This point-by-point division operation eliminates the influence of factors such as signal source unevenness, cable loss, and gain fluctuations of the measurement unit 430 channels, ultimately yielding a pure amplitude calibration parameter array that reflects only the relative gain or attenuation characteristics of the probe 10 at each frequency point.

[0144] This array of amplitude calibration parameters will be stored in the non-volatile memory of the oscilloscope 20, or written back to the memory chip inside the probe 10 via a digital communication interface. This allows the test system to retrieve the corresponding gain calibration value from the array based on the current operating frequency when acquiring the signal under test in real time. This enables precise reverse compensation for the amplitude attenuation or frequency-selective fluctuations introduced by the probe 10, thereby ensuring that the waveform amplitude finally displayed by the oscilloscope 20 can truly reproduce the original signal characteristics of the measured point.

[0145] For phase frequency response, specifically including:

[0146] Frequency domain transformations are performed on the first time-domain waveform and the second time-domain waveform respectively. Based on the transformation results, the first set of phase values ​​and the second set of phase values ​​corresponding to each frequency point are extracted to generate the first phase frequency response array and the second phase frequency response array. Then, the second phase frequency response array and the first phase frequency response array are subtracted element by element to obtain the phase calibration parameter array of the probe corresponding to each frequency point.

[0147] After capturing the waveform data, mathematical algorithms such as the Fast Fourier Transform (FFT) are needed to decompose the first and second time-domain waveforms, representing amplitude changes over time, into a combination of a series of discrete frequency components. The transformed frequency-domain data can clearly present the amplitude and phase information of each frequency component, making the phase characteristics originally implicit in the waveform shape explicit.

[0148] After completing the frequency domain transformation, for each discrete frequency point covering the operating frequency band of probe 10, the corresponding phase angle is extracted from the transformation result of the first time domain waveform to form a first phase frequency response array. This array characterizes the phase frequency characteristics of the link itself without probe 10. Similarly, the phase angle of each frequency point is extracted from the transformation result of the second time domain waveform to form a second phase frequency response array, which reflects the phase frequency characteristics of the entire system including probe 10. The generation of these two phase frequency response arrays realizes the quantization of continuous phase characteristics into a structured digital sequence.

[0149] Finally, since the second phase array is the sum of the probe 10 phase and the link phase, while the first phase array only represents the link phase, the net phase offset introduced by the probe 10 itself can be accurately isolated by subtracting the corresponding phase value of the first array from the phase value of the second array at each frequency point. This point-by-point subtraction operation effectively eliminates the influence of factors such as the initial phase of the signal source, cable transmission delay, and phase shift of the measurement unit 430 channel, ultimately obtaining a set of calibration parameters that only reflects the phase change characteristics of the probe 10 at each frequency point.

[0150] Similarly, this array of phase calibration parameters will be stored in the non-volatile memory of the oscilloscope 20, or written back to the memory chip inside the probe 10 via the digital communication interface, so that when the test system acquires the signal under test in real time, it can retrieve the corresponding phase calibration value from the array according to the current operating frequency, and accurately compensate for the amplitude attenuation or frequency selective fluctuation introduced by the probe 10, thereby ensuring that the waveform phase finally displayed by the oscilloscope 20 can truly restore the original signal characteristics of the measured point.

[0151] In summary, the method for generating probe frequency response calibration parameters in the first manner provided in any of the above embodiments, by introducing a composite test signal including a steady-state sweep signal and a transient pulse signal, and combining frequency response data acquisition in two stages—without probe connection and with probe connection—achieves accurate quantification and characterization of the non-ideal characteristics of the signal source, connecting cables, and the measurement unit itself. Based on this, by performing vector de-embedding calculations in the complex frequency domain on the reference frequency response dataset and the system frequency response dataset—that is, dividing the amplitude to eliminate link gain deviation and subtracting the phase to remove channel phase offset—accurate extraction of the probe's independent frequency response characteristics is achieved. This parameter generation method eliminates system errors introduced by the test environment and the back-end measurement link, improves the calibration accuracy of the probe's amplitude-frequency and phase-frequency characteristics across the entire operating frequency band, and provides a reliable basis for oscilloscopes and other measurement equipment to implement accurate real-time anti-distortion compensation in actual signal acquisition through the output of digital calibration parameters.

[0152] Figure 6 A flowchart illustrating a method for determining probe frequency response calibration parameters according to another embodiment of this application. Figure 6 As shown, in the above embodiment, step S240, generating the probe's frequency response calibration parameters using a second method within the second sub-band above the transition frequency point, specifically includes the following steps:

[0153] Step S2401: Obtain the complex transmission parameter dataset obtained from measurements of multiple probes of the same model.

[0154] Considering that the measurement data of a single probe 10 in the high-frequency band may exhibit significant random fluctuations due to system noise, impedance mismatch, or individual manufacturing differences, directly using the measurement results of a single probe 10 is insufficient to obtain stable and reliable calibration parameters. Therefore, this step selects multiple probes 10 of the same model as samples, and measures each probe 10 separately, collecting its complex transmission parameters across the entire operating frequency band. These complex transmission parameters can be S21 parameters, which simultaneously contain amplitude and phase information, and can comprehensively describe the transmission characteristics of the probe 10. By using measurement data from multiple probes 10, the statistical distribution characteristics of this model of probe 10 in the high-frequency band can be obtained more accurately, avoiding the problem that relying solely on data from a single probe 10 may result in calibration parameters lacking universality.

[0155] In some embodiments, a network analyzer is used as the core measurement device to perform the acquisition of complex transmission parameters.

[0156] A network analyzer is a precision instrument specifically designed to measure the frequency response of electrical networks. Its advantage lies in its ability to simultaneously capture the amplitude changes and phase shifts of the device under test (i.e., probe 10) in a single scan and accurately output its transmission characteristics in complex form (such as rectangular or polar coordinates). In practice, the operator sequentially connects multiple probes 10 of the same model to the test port of the network analyzer. The instrument's built-in signal source transmits a sweep signal covering a specified frequency band to the probes 10. Simultaneously, the receiving end accurately measures the amplitude and phase of the signal transmitted through the probes, thereby automatically generating a complex transmission parameter dataset for each probe 10.

[0157] Step S2402: Process the complex transmission parameter dataset to obtain the processed frequency response data.

[0158] Further statistical analysis and optimization are needed on the acquired raw discrete datasets of multiple probes 10, which contain individual differences, to extract frequency response data that can represent the common characteristics of this model of probe 10, eliminate measurement noise, and smooth individual fluctuations. Data processing methods may include, but are not limited to: removing obviously abnormal outlier sample data, calculating the mean amplitude and mean phase values ​​of multiple probes 10 at the same frequency point, smoothing and filtering the mean curve, and normalization and linear transformation. The frequency response data obtained after data processing, after optimization and purification, can more realistically and stably reflect the typical characteristics of this model of probe 10 in the high-frequency band, and is a reliable basis for generating high-frequency calibration parameters.

[0159] In some embodiments, data processing is performed on the complex transmission parameter dataset, specifically including:

[0160] The complex transmission parameter dataset is averaged and smoothed to obtain smoothed complex frequency response data; the amplitude part of the smoothed complex frequency response data is normalized and linearly transformed to obtain linear amplitude frequency response data; the smoothed complex frequency response data is phase extracted to obtain phase frequency response data.

[0161] In this embodiment, the systematic processing of the raw measurement data from multiple probes 10 eliminates individual discreteness and measurement noise, extracting clean and standardized frequency response characteristic data, specifically as follows:

[0162] First, the complex transmission parameter dataset collected by the network analyzer is averaged and smoothed. This involves averaging the complex measurements of multiple samples at the same frequency point to suppress random errors and extracting typical response trends representing the common characteristics of the probe model 10. Then, moving averages or filtering algorithms are used to eliminate glitches and noise on the curve, resulting in a smooth complex frequency response curve that represents the common characteristics of the probe model 10. This data retains both amplitude and phase information. Next, the amplitude component is separated from the smoothed complex data. Using the amplitude value at a reference frequency point (e.g., a low-frequency reference point) as a benchmark, the amplitude data for the entire frequency band is normalized to convert it into relative values, eliminating the influence of absolute amplitude. Logarithmic operations are then used to convert it into linear amplitude data, providing a clear view of the amplitude's relationship with frequency. Simultaneously, phase extraction is performed on the smoothed complex frequency response data to directly obtain phase frequency response data reflecting the phase characteristics of the probe model 10. This process transforms the original measurement data into clean and easily fitted linear amplitude and phase response data.

[0163] Step S2403: Based on the portion of the processed frequency response data corresponding to the second sub-band, generate calibration parameters applicable to the second sub-band.

[0164] As mentioned above, the response in the high-frequency band is usually more complex and individual differences may be more significant. To better adapt to the same model probe 10 and achieve better calibration results in the high-frequency band, the second calibration generation method focuses more on the second sub-frequency band (i.e., the high-frequency band above the transition frequency point). After obtaining the processed frequency response data, the part of the processed data corresponding to the second sub-frequency band is modeled to determine the trend of the gain and phase of probe 10 with frequency in this frequency band, and finally the gain calibration parameters and phase calibration parameters corresponding to each frequency point in the second sub-frequency band are generated.

[0165] In some embodiments, calibration parameters applied to the second sub-band are generated based on the portion of the processed frequency response data corresponding to the second sub-band, specifically including:

[0166] A function is fitted to the portion of the linear amplitude frequency response data corresponding to the second sub-band. Based on the fitting results, the gain calibration parameters for each frequency point within the second sub-band are determined. A function is fitted to the portion of the phase frequency response data corresponding to the second sub-band. Based on the fitting results, the phase calibration parameters for each frequency point within the second sub-band are determined.

[0167] Considering the practical problems of dense discrete data points and high storage pressure in the second sub-band (high frequency band), a function fitting method is adopted to generate calibration parameters to achieve data compression and characteristic generalization. Specifically, firstly, for linear amplitude frequency response data, a suitable mathematical model (such as a linear function, polynomial, etc.) is selected to perform curve fitting on the discrete amplitude points corresponding to the second sub-band (high frequency band), so that the fitting function can smoothly describe the overall trend of amplitude change with frequency. Then, based on the fitting result, the gain calibration parameters of each frequency point in the band can be calculated, thereby suppressing abnormal fluctuations at individual frequency points and reducing the number of discrete data points that need to be stored. Similarly, for phase frequency response data, a corresponding function model is also used to fit the discrete phase points in the second sub-band (high frequency band) to obtain a mathematical expression that can continuously characterize the phase shift characteristics. Based on the fitting result, the phase calibration parameters of each frequency point in the band are determined, and the phase characteristics are also efficiently characterized by the fitting model. This approach not only yields robust and reliable high-frequency calibration parameters, but also transforms a large amount of discrete data that would otherwise need to be stored point by point into a few fitting coefficients. This significantly reduces storage overhead and, by leveraging the continuity of the fitting function, enables rapid and accurate calculation of calibration parameters at any frequency point, avoiding interpolation errors between discrete points.

[0168] In summary, the method for generating probe frequency response calibration parameters in the second manner provided in any of the above embodiments effectively suppresses random errors and non-essential fluctuations introduced by system noise, impedance mismatch, and individual manufacturing differences in high-frequency measurements by acquiring complex transmission parameter datasets from multiple probes of the same model and performing a series of data processing steps such as averaging, smoothing, normalizing, and linear transformation. This results in smooth amplitude and phase data that truly reflect the common high-frequency characteristics of the probe model. Furthermore, by performing function fitting on the data in the second sub-frequency band, discrete measurement values ​​are transformed into continuous and smooth mathematical models. This not only eliminates the inherent instability and discreteness of high-frequency data and improves the robustness and reproducibility of calibration parameters, but also achieves effective compression of high-frequency calibration data, reducing storage overhead. Ultimately, this ensures that the probe can obtain reliable and consistent gain and phase compensation effects in the high-frequency band, laying a solid foundation for accurate measurement of the probe across the entire frequency band.

[0169] After successfully obtaining the gain and phase calibration parameter set of probe 10 across the entire operating frequency band, with the transition frequency point as the boundary, using the probe frequency response calibration parameter determination method provided in any of the above embodiments, for example... Figure 1 In the actual measurement process, the probe frequency response calibration parameters of the measurement system shown will be used to compensate for the frequency response of the measured signal acquired by probe 10.

[0170] This application further proposes a frequency response compensation method. This method makes full use of the established probe frequency response calibration parameter set containing transition frequency points, combined with the channel calibration parameters of the oscilloscope 20 itself, and intelligently selects differentiated compensation strategies based on the transition frequency points for the measured signal after the probe 10 is actually connected to the measurement system. This effectively eliminates the amplitude and phase frequency distortions introduced by the probe 10 and the oscilloscope 20 channels, achieves accurate correction of the frequency response of the entire measurement system, and ensures that the signal finally displayed by the oscilloscope 20 can truly reproduce the original waveform of the measured point.

[0171] The frequency response compensation method proposed in this application will now be described in detail with reference to the accompanying drawings.

[0172] Figure 7 This is a flowchart illustrating a frequency response compensation method according to an embodiment of this application. The frequency response compensation method provided in this embodiment can be applied to, for example... Figure 1 The measurement system shown includes probe 10 and oscilloscope 20, such as Figure 7 As shown, the method specifically includes the following steps:

[0173] Step S710: Obtain the frequency response calibration parameters of the probe and the channel calibration parameters of the oscilloscope itself; wherein, the frequency response calibration parameters of the probe are determined by the method for determining the probe frequency response calibration parameters described in any of the above embodiments, and include at least the probe gain calibration parameters, the probe phase calibration parameters, and the transition frequency point.

[0174] The oscilloscope 20 is endowed with intelligent interaction and compensation capabilities. When the probe 10 is connected, on the one hand, the oscilloscope 20 can actively identify and acquire the probe frequency response calibration parameter set determined by the method of any of the above embodiments, which is stored in the probe 10 or the system storage unit. This includes probe gain calibration parameters, probe phase calibration parameters, and transition frequency points used to identify the inflection points of the probe response characteristics. On the other hand, it simultaneously acquires the calibration parameters of the oscilloscope 20's own measurement channel. These parameters reflect the frequency response characteristics of the oscilloscope 20 channel itself and typically include channel gain calibration parameters and channel phase calibration parameters.

[0175] Step S720: Based on the probe's operating frequency band and transition frequency point, select a compensation strategy from multiple compensation strategies to compensate for the frequency response of the measured signal acquired by the probe.

[0176] The oscilloscope 20 can accurately identify the boundary between the low-frequency flat region and the high-frequency complex region of the probe 10's response by using the transition frequency point. Based on this, strategic decisions are made according to the relationship between the inherent properties of the probe 10 (i.e., the probe 10's operating frequency band) and the pre-determined transition frequency point. It is important to note that the probe 10's operating frequency band mentioned here refers to the probe 10's designed rated operating frequency band, i.e., the frequency range within which the probe 10 can operate normally, not the real-time frequency range of the currently measured signal. By determining the relative positional relationship between the probe 10's rated operating frequency band and the transition frequency point, and considering the physical meaning of the transition frequency point, the oscilloscope 20 intelligently selects the compensation scheme that best matches the current characteristics of the probe 10 from a variety of pre-set compensation strategies. For example, based on whether the highest frequency of the probe 10's rated operating frequency band is higher than the transition frequency point, and whether the transition frequency point is determined based on amplitude attenuation or phase deviation, the most suitable strategy is selected from multiple compensation strategies to balance computational complexity and compensation accuracy, ensuring optimal processing efficiency across different frequency bands.

[0177] Step S730: Determine the corresponding probe frequency response calibration parameters according to the selected compensation strategy.

[0178] In this embodiment, different compensation strategies correspond to different selection methods for subsets in the probe frequency response calibration parameter set. For example, some strategies may require selecting gain and phase parameters generated using the first method across the entire operating frequency band; other strategies may require distinguishing between the first and second sub-frequency bands, selecting gain parameters generated using either the first or second method respectively, while phase parameters may be generated entirely using the first method. After determining the frequency response compensation strategy based on the relationship between the probe 10's operating frequency band and transition frequency point, the subset of parameters matching this compensation strategy that needs to be extracted from the stored complete probe frequency response calibration parameter set is also determined.

[0179] Step S740: Based on the determined probe frequency response calibration parameters and channel frequency response calibration parameters, perform frequency response compensation on the measured signal.

[0180] Finally, the oscilloscope 20 will apply corresponding compensation processing to the measured signal acquired through the probe 10 using the selected probe calibration parameters and its own channel calibration parameters. Before compensation, the probe frequency response calibration parameters and the oscilloscope 20's own channel calibration parameters need to be aligned at frequency points. Interpolation or resampling algorithms are used to map the two sets of data onto a unified frequency coordinate axis, ensuring they have the same number of frequency points and frequency intervals, thus obtaining aligned probe frequency response calibration parameters. Subsequently, based on the aligned probe gain calibration parameters and channel gain calibration parameters, the actual gain of the measurement system is calculated. According to the relationship between the actual gain and the preset ideal gain, gain compensation parameters are generated, and the measured signal is filtered using these parameters to achieve gain frequency response compensation. Furthermore, based on the aligned probe phase calibration parameters and channel phase calibration parameters, phase compensation parameters are generated, and the measured signal is phase-corrected using these parameters to achieve phase frequency response compensation. Frequency response compensation can eliminate amplitude and phase distortion introduced by the probe 10 itself, achieving full-link signal fidelity from the front end of the probe 10 to the display terminal of the oscilloscope 20, ensuring that the final waveform can accurately reproduce the original state of the measured point, thereby improving the accuracy and reliability of the entire measurement system in complex signal testing.

[0181] It should be noted that the core innovation of the frequency response compensation method proposed in this application does not lie in the specific details of how to use the calibration parameters of probe 10 and oscilloscope 20 to perform digital filtering or phase correction, but rather in how to intelligently determine differentiated frequency response compensation strategies based on the inherent relationship between the operating frequency band and transition frequency point of probe 10. The details of the compensation execution will not be elaborated here; the following will explain how to further determine the probe frequency response calibration parameters to be extracted after determining the compensation strategy.

[0182] Figure 8 A flowchart illustrating a frequency response compensation method provided in another embodiment of this application. Figure 8 As shown, in the above embodiment, step S720, selecting a compensation strategy from multiple compensation strategies to compensate for the frequency response of the measured signal acquired by the probe based on the probe's operating frequency band and transition frequency point, specifically includes:

[0183] Step S7201: Determine the relationship between the highest frequency of the probe's operating frequency band and the transition frequency point.

[0184] As mentioned earlier, when determining the compensation strategy for frequency response compensation of the measured signal acquired by probe 10, the relative magnitude between the highest frequency of the operating frequency band of probe 10 and the transition frequency point is used to determine the positional relationship between the overall operating range of probe 10 and the transition frequency point. In other words, it determines the characteristic distribution of probe 10 throughout the entire frequency band: whether it is a "low-frequency" characteristic entirely below the transition frequency point, or a "full-frequency" characteristic spanning the transition frequency point.

[0185] Step S7202: When the highest frequency of the probe's operating frequency band is lower than or equal to the transition frequency point, select the first compensation strategy to perform frequency response compensation.

[0186] In this embodiment, the first compensation strategy is to select the gain compensation parameters and phase compensation parameters corresponding to the probe in all operating frequency bands, generated in a first manner, as probe frequency response calibration parameters for frequency response compensation.

[0187] When the highest frequency of the rated operating frequency band of probe 10 is exactly equal to the transition frequency point, it indicates that probe 10 will always operate in a region with relatively stable frequency response and reliable measurement data during actual use. In this case, there is no need to divide the frequency band; the first compensation strategy can be directly selected for compensation, i.e., directly calling the gain and phase calibration parameters covering the entire rated frequency band generated in the first method. The core of the first compensation strategy is to process the entire operating frequency band in a unified way, specifically by compensating entirely based on the probe frequency response calibration parameters generated in the first method. This strategy fully utilizes the high precision characteristics of low-frequency parameters and has low computational overhead. It not only ensures that probe 10 obtains consistent and accurate compensation results throughout its entire operating range, avoiding unnecessary frequency band division and parameter mixing, but also improves compensation efficiency.

[0188] Step S7203: When the highest frequency in the probe's operating frequency band is higher than the transition frequency point, and the transition frequency point is determined based on the amplitude attenuation of the probe's amplitude frequency response curve, select the second compensation strategy for frequency response compensation.

[0189] In this embodiment, the second compensation strategy is to select the phase compensation parameters generated in the first manner corresponding to the probe in all operating frequency bands, the gain compensation parameters generated in the first manner corresponding to the probe in the first sub-frequency band, and the gain compensation parameters generated in the second manner corresponding to the probe in the second sub-frequency band, and use them together as probe frequency response calibration parameters for frequency response compensation.

[0190] When the rated operating frequency band of probe 10 crosses the transition frequency point (i.e., the highest frequency is higher than the transition frequency point), and this transition frequency point is determined by analyzing the amplitude attenuation of the amplitude frequency response curve, it indicates that probe 10 mainly faces gain attenuation problems in the high-frequency band, while the phase characteristics may be relatively stable or have not yet deteriorated significantly. In this case, the second compensation strategy is selected for frequency response compensation. The core of the second compensation strategy lies in the differentiated processing of gain and phase: considering that the phase response usually has better continuity, the phase compensation across the entire frequency band still uses the phase calibration parameters generated by the first method to maintain consistency; while for the amplitude response, segmented processing is performed, that is, in the first sub-band below the transition frequency point, the gain parameters generated by the first method continue to be used to ensure efficiency, while in the second sub-band above the transition frequency point, the high-precision gain parameters generated by the second method are switched to correct complex attenuation. This combination strategy of globally unified phase and finely segmented gain not only accurately addresses the difficulty of correcting high-frequency amplitude roll-off, but also avoids redundant calculations caused by using complex algorithms across the entire frequency band, achieving an optimal balance between compensation accuracy and resource consumption.

[0191] In some embodiments, the compensation strategy selected from multiple compensation strategies for frequency response compensation of the measured signal acquired by the probe further includes:

[0192] Step S7204: When the highest frequency in the probe's operating frequency band is higher than the transition frequency point, and the transition frequency point is determined based on the phase deviation of the probe's amplitude-frequency response curve, select the third compensation strategy for frequency response compensation.

[0193] In this embodiment, the third compensation strategy is to select the gain compensation parameters and phase compensation parameters generated in the first manner corresponding to the probe in the first sub-frequency band, and the gain compensation parameters and phase compensation parameters generated in the second manner corresponding to the probe in the second sub-frequency band, and use them together as probe frequency response calibration parameters for frequency response compensation.

[0194] In addition to the two compensation strategies mentioned above, some embodiments also include a third compensation strategy employed under specific conditions. When the rated operating frequency band of probe 10 crosses a transition frequency point (i.e., the highest frequency is higher than the transition frequency point), and this transition frequency point is determined based on the phase deviation of the phase frequency response curve of probe 10, it indicates that probe 10 not only faces gain attenuation in the high-frequency band, but its phase characteristics have also exhibited significant nonlinear deviations. In this case, the third compensation strategy is selected for frequency response compensation. The core of the third compensation strategy lies in using a segmented processing method for both gain and phase: in the first sub-frequency band (below or equal to the transition frequency point), the gain compensation parameters and phase compensation parameters generated in the first method are selected for compensation, making full use of the high-precision characteristics of the low-frequency parameters; in the second sub-frequency band (above the transition frequency point), the gain compensation parameters and phase compensation parameters generated in the second method are selected simultaneously for compensation, using the second method parameters based on statistical fitting to robustly characterize the complex frequency response characteristics of the high-frequency band. Through this strategy of segmented processing of both gain and phase, the amplitude distortion and phase distortion of probe 10 in the high-frequency band can be comprehensively corrected, ensuring that probe 10 obtains accurate and consistent compensation effects throughout the entire rated operating frequency band.

[0195] In summary, the frequency response compensation method provided in any of the above embodiments achieves adaptive optimization of compensation accuracy and computational efficiency by introducing a dynamic strategy selection mechanism based on the relationship between the probe's rated operating frequency band and the transition frequency point. Specifically, this method first uses the transition frequency point explicitly identified in the probe calibration parameters, combined with the probe's own rated bandwidth range, to determine the complexity of its response characteristics: when the rated bandwidth is entirely within the low-frequency stable region, a unified and efficient compensation strategy is adopted to minimize resource consumption; when the rated bandwidth crosses the transition point determined by amplitude attenuation, segmented fine compensation is performed on the amplitude response to maintain the consistency of phase compensation; when the rated bandwidth crosses the transition point determined by phase deviation, segmented high-precision compensation is performed on both amplitude and phase.

[0196] This multi-strategy compensation architecture, which adapts to different frequencies and parameters, not only ensures that the probe achieves accurate calibration matching its response characteristics across the entire rated frequency band, but also effectively avoids computational redundancy caused by overusing complex algorithms in simple frequency bands. Furthermore, it significantly improves the fidelity of broadband signal measurements through specialized responses to phase transition points. Ultimately, this method enables the oscilloscope measurement system to intelligently match the optimal compensation path based on the probe's own characteristics, maximizing processing efficiency while ensuring measurement accuracy. It provides a flexible and robust solution for high-speed signal acquisition and accurate reconstruction.

[0197] This application also provides a readable storage medium storing a program or instructions. When the program or instructions are executed by a processor, they implement various processes of any embodiment of the above-described method for determining probe frequency response calibration parameters and / or frequency response compensation method, and achieve the same technical effect. To avoid repetition, these will not be described again here.

[0198] The processor can be a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of this application. The readable storage medium includes computer-readable storage media, such as computer read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk.

[0199] Those skilled in the art will understand that all or part of the functions of the various methods in the above embodiments can be implemented by hardware or by computer programs. When all or part of the functions in the above embodiments are implemented by computer programs, the program can be stored in a computer-readable storage medium, which may include: read-only memory, random access memory, disk, optical disk, hard disk, etc., and the program is executed by a computer to achieve the above functions. For example, the program can be stored in the memory of a device, and when the program in the memory is executed by the processor, all or part of the above functions can be achieved. In addition, when all or part of the functions in the above embodiments are implemented by computer programs, the program can also be stored in a server, another computer, disk, optical disk, flash drive, or external hard drive, etc., and can be downloaded or copied to the memory of a local device, or the system of the local device can be updated. When the program in the memory is executed by the processor, all or part of the functions in the above embodiments can be achieved.

[0200] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art, under the guidance of this application, can make several simple deductions, modifications or substitutions based on the spirit of this application and the scope of protection of the claims without departing from the spirit of this application and the claims. All of these are within the protection scope of this application.

Claims

1. A method for determining probe frequency response calibration parameters, characterized in that, include: Acquire frequency response measurement data of the probe within its operating frequency band; Based on the frequency response measurement data, determine the transition frequency point of the probe within the operating frequency band; Within a first sub-frequency band below or equal to the transition frequency point, the frequency response calibration parameters of the probe are generated using a first method. In the second sub-band above the transition frequency point, the frequency response calibration parameters of the probe are generated using a second method; The first method and the second method are different, and the frequency response calibration parameters include gain calibration parameters and phase calibration parameters.

2. The method for determining the probe frequency response calibration parameters according to claim 1, characterized in that, Determining the transition frequency point of the probe within the operating frequency band based on the frequency response measurement data includes: Based on the frequency response measurement data, determine the amplitude frequency response curve and / or phase frequency response curve of the probe; Based on the amplitude frequency response curve, identify the frequency point where the amplitude decays to a first preset threshold; and / or, based on the phase frequency response curve, identify the frequency point where the phase deviation reaches a second preset threshold. The identified frequency point is determined as the transition frequency point.

3. The method for determining the probe frequency response calibration parameters according to claim 1, characterized in that, The second method for generating calibration parameters includes: Obtain a dataset of complex transmission parameters measured from multiple probes of the same model; The complex transmission parameter dataset is processed to obtain processed frequency response data; Based on the portion of the processed frequency response data corresponding to the second sub-frequency band, calibration parameters are generated for the second sub-frequency band.

4. The method for determining the probe frequency response calibration parameters according to claim 3, characterized in that, The step of processing the complex transmission parameter dataset to obtain processed frequency response data includes: The complex transmission parameter dataset is averaged and smoothed to obtain smoothed complex frequency response data; The amplitude portion of the smoothed complex frequency response data is normalized and linearly transformed to obtain linear amplitude frequency response data. Phase extraction is performed on the smoothed complex frequency response data to obtain phase frequency response data.

5. The method for determining the probe frequency response calibration parameters according to claim 4, characterized in that, The step of generating calibration parameters for the second sub-frequency band based on the portion of the processed frequency response data corresponding to the second sub-frequency band includes: The portion of the linear amplitude frequency response data corresponding to the second sub-band is fitted with a function, and the gain calibration parameters for each frequency point in the second sub-band are determined based on the fitting results. A function is fitted to the portion of the phase frequency response data corresponding to the second sub-band, and the phase calibration parameters for each frequency point within the second sub-band are determined based on the fitting results.

6. The method for determining the probe frequency response calibration parameters according to claim 1, characterized in that, The generation of calibration parameters using the first method includes: Obtain a reference frequency response dataset of the calibration system's response to the test signal when the probe is not connected; Obtain the system frequency response dataset of the calibration system in response to the same test signal when the probe is connected; De-embedding calculations are performed on the reference frequency response dataset and the system frequency response dataset to determine the frequency response calibration parameters of the probe; The calibration system includes at least a signal generation unit for generating test signals and a measurement unit for measuring frequency response; the test signals cover the entire operating frequency band of the probe and include a first type of test signal for exciting steady-state amplitude response and a second type of test signal for exciting transient phase response.

7. The method for determining the probe frequency response calibration parameters according to claim 6, characterized in that, The reference frequency response dataset of the calibration system in response to the test signal when no probe is connected includes: The signal generation unit is controlled to output the first type of test signal in sequence according to a preset frequency sequence, and the measurement unit synchronously measures the signal amplitude value corresponding to each frequency point to obtain the first set of amplitude measurement results. The signal generation unit is controlled to output the second type of test signal, and the corresponding first time-domain waveform is captured by the measurement unit. The acquisition of the system frequency response dataset of the calibration system in response to the same test signal when the probe is connected includes: The signal generation unit is controlled to output the first type of test signal sequentially according to the same preset frequency sequence, and the measurement unit synchronously measures the signal amplitude value corresponding to each frequency point to obtain the second set of amplitude measurement results. The signal generation unit is controlled to output the second type of test signal, and the corresponding second time-domain waveform is captured by the measurement unit.

8. The method for determining the probe frequency response calibration parameters according to claim 7, characterized in that, Also includes: Select any frequency point as the reference point; Based on the signal amplitude value corresponding to the reference point, the first set of amplitude measurement results and the second set of amplitude measurement results are normalized respectively. Generate the first amplitude frequency response array and the second amplitude frequency response array corresponding to each frequency point respectively; Perform frequency domain transformation on the first time-domain waveform and the second time-domain waveform respectively; Based on the transformation results, the first set of phase values ​​and the second set of phase values ​​corresponding to each frequency point are extracted to generate the first phase frequency response array and the second phase frequency response array.

9. The method for determining the probe frequency response calibration parameters according to claim 8, characterized in that, The step of performing de-embedding calculations on the reference frequency response dataset and the system frequency response dataset to determine the frequency response calibration parameters of the probe includes: The amplitude frequency response data corresponding to each frequency point in the second amplitude frequency response array and the first amplitude frequency response array are divided to obtain the gain calibration parameter array of the probe corresponding to each frequency point. The second phase frequency response array and the first phase frequency response array are subtracted element by element to obtain the phase calibration parameter array of the probe corresponding to each frequency point.

10. A frequency response compensation method, applied to a measurement system including a probe and an oscilloscope, characterized in that, include: The frequency response calibration parameters of the probe and the channel calibration parameters of the oscilloscope itself are obtained; wherein the frequency response calibration parameters of the probe are determined by the method for determining the frequency response calibration parameters of the probe as described in any one of claims 1 to 9, and at least include the probe gain calibration parameters, the probe phase calibration parameters, and the transition frequency point; Based on the probe's operating frequency band and the transition frequency point, a compensation strategy is selected from multiple compensation strategies to compensate for the frequency response of the measured signal acquired through the probe. Determine the corresponding probe frequency response calibration parameters based on the selected compensation strategy; Based on the determined probe frequency response calibration parameters and channel frequency response calibration parameters, frequency response compensation is performed on the measured signal.

11. The frequency response compensation method according to claim 10, characterized in that, The compensation strategy for compensating the frequency response of the measured signal acquired by the probe, selected from multiple compensation strategies based on the probe's operating frequency band and the transition frequency point, includes: Determine the relationship between the highest frequency of the probe's operating frequency band and the transition frequency point; When the highest frequency in the probe's operating frequency band is lower than or equal to the transition frequency point, the first compensation strategy is selected for frequency response compensation. When the highest frequency in the probe's operating frequency band is higher than the transition frequency point, and the transition frequency point is determined based on the amplitude attenuation of the probe's amplitude frequency response curve, a second compensation strategy is selected for frequency response compensation.

12. The frequency response compensation method according to claim 11, characterized in that, The first compensation strategy is to select the gain compensation parameters and phase compensation parameters corresponding to the probe in all operating frequency bands, generated in a first manner, as probe frequency response calibration parameters for frequency response compensation. The second compensation strategy involves selecting phase compensation parameters generated in the first manner corresponding to the probe in all operating frequency bands, gain compensation parameters generated in the first manner corresponding to the probe in the first sub-frequency band, and gain compensation parameters generated in the second manner corresponding to the probe in the second sub-frequency band, which together serve as probe frequency response calibration parameters for frequency response compensation.

13. The frequency response compensation method according to claim 10, characterized in that, The compensation strategy for compensating the frequency response of the measured signal acquired by the probe, selected from multiple compensation strategies based on the probe's operating frequency band and the transition frequency point, further includes: When the highest frequency in the probe's operating frequency band is higher than the transition frequency point, and the transition frequency point is determined based on the phase deviation of the probe's amplitude frequency response curve, a third compensation strategy is selected for frequency response compensation. The third compensation strategy involves selecting gain compensation parameters and phase compensation parameters generated in the first manner corresponding to the probe in the first sub-frequency band, and gain compensation parameters and phase compensation parameters generated in the second manner corresponding to the probe in the second sub-frequency band, which are then used together as probe frequency response calibration parameters for frequency response compensation.

14. A measurement system, characterized in that, include: probe; An oscilloscope is configured to acquire a set of probe frequency response calibration parameters determined by the method for determining probe frequency response calibration parameters as described in any one of claims 1 to 9 and its own channel calibration parameters, and to perform frequency response compensation on the measured signal acquired by the probe according to the set of probe frequency response calibration parameters and its own channel calibration parameters, using the frequency response compensation method as described in any one of claims 10 to 13.

15. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer-executable program or instructions, which, when executed by a processor, are used to implement the method for determining the probe frequency response calibration parameters as described in any one of claims 1 to 9, and / or the frequency response compensation method as described in any one of claims 10 to 13.

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