Multi-channel data synchronous acquisition method and oscilloscope
By employing a dual-frequency calibration scheme and a phase difference measurement method, the measurement error problem caused by inter-channel delay difference in multi-channel oscilloscopes was solved, achieving high-precision channel data synchronization and self-calibration performance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-30
- Publication Date
- 2026-04-03
AI Technical Summary
In multi-channel oscilloscopes, the time delay caused by physical differences between channels leads to high-frequency signal measurement errors, affecting measurement accuracy and precision.
A dual-frequency calibration scheme is adopted, which uses calibration signals with coprime frequencies to perform two phase difference measurements, calculates the picosecond-level delay parameters between channels, obtains the initial phase value using Hilbert transform and dewinding calculation, and combines a defuzzification algorithm to eliminate periodic ambiguity problems and achieve channel data synchronization.
Accurately calculate inter-channel delay parameters to improve calibration accuracy and reliability, compensate for delay differences caused by hardware manufacturing and temperature variations, and ensure measurement consistency and high accuracy.
Smart Images
Figure CN121784340A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the technical field of broadband interleaved acquisition systems, specifically relating to a multi-channel data synchronous acquisition method and an oscilloscope. Background Technology
[0002] Digital oscilloscopes are indispensable measurement instruments in the field of electronic engineering. They sample the signal under test through one or more acquisition channels to analyze the signal's time and frequency domain characteristics. In high-end applications, multi-channel oscilloscopes are widely used to simultaneously observe and analyze multiple interrelated signals, such as multiple data channels of a high-speed serial bus or the input and output signals of a device. In these application scenarios, accurately measuring the timing relationships between signals, such as delay, jitter, and eye diagram parameters, is crucial.
[0003] To ensure measurement accuracy, highly precise time synchronization must be achieved between the various acquisition channels of a multi-channel oscilloscope. However, in actual hardware systems, due to physical differences in printed circuit board (PCB) trace lengths and inherent delays in components such as internal amplifiers and analog-to-digital converters (ADCs), a small but constant time delay inevitably occurs as the signal flows through different acquisition channels—this is known as channel-to-channel skew. For modern high-speed signals with frequencies up to GHz, even picosecond (ps) level channel-to-channel skew can lead to significant measurement errors, resulting in incorrect assessments of the device under test's performance. Summary of the Invention
[0004] The purpose of this invention is to provide a multi-channel data synchronous acquisition method and an oscilloscope.
[0005] To achieve the above objectives, in a first aspect, the present invention provides a multi-channel data synchronous acquisition method for an oscilloscope. The oscilloscope includes a first sampling channel, a second sampling channel, and a first data processing module. Each of the first and second sampling channels includes an analog-to-digital conversion module and a second data processing module. The first and second sampling channels perform channel data synchronous acquisition and alignment by receiving calibration signals. The calibration signals include a first calibration signal and a second calibration signal with coprime frequencies. The method includes:
[0006] The first data processing module controls the analog-to-digital conversion modules of the first sampling channel and the second sampling channel to acquire the first calibration signal and obtain the first sampling data. The first data processing module controls the second data processing modules of the first sampling channel and the second sampling channel to process the first sampling data to obtain the first starting phase value, and calculates the first phase difference value based on the first starting phase value of the first sampling channel and the second sampling channel.
[0007] The first data processing module controls the analog-to-digital conversion modules of the first sampling channel and the second sampling channel to acquire the second calibration signal and obtain the second sampling data. The first data processing module controls the second data processing modules of the first sampling channel and the second sampling channel to process the second sampling data to obtain the second starting phase value, and calculates the second phase difference based on the second starting phase value of the first sampling channel and the second sampling channel.
[0008] The first data processing module calculates a delay parameter based on the first phase difference and the second phase difference, and completes data synchronization between the first sampling channel and the second sampling channel based on the delay parameter.
[0009] In some embodiments, the first data processing module controls the second data processing modules of the first sampling channel and the second sampling channel respectively to process the first sampled data to obtain a first starting phase value, including:
[0010] Perform a Hilbert transform on the first sampled data and obtain the first phase value in the complex domain;
[0011] The first initial phase value is obtained by performing unwinding calculation on the first phase value.
[0012] In some embodiments, the first data processing module controls the second data processing modules of the first sampling channel and the second sampling channel respectively to process the first sampled data to obtain a first starting phase value, including:
[0013] A preset sampling time window is set in the first data processing module;
[0014] The first sampled data is subjected to a fast Fourier transform to obtain a first spectrum, and each spectral point of the first spectrum contains the amplitude and phase of the corresponding frequency.
[0015] Obtain the spectral points corresponding to the first calibration signal, perform complex domain transformation and extract the phase value, the phase value corresponding to the phase of the first sampled data at the center point of the preset sampling time window;
[0016] The first initial phase value is obtained by performing phase correction based on the total duration of the sampling time window.
[0017] In some embodiments, the first data processing module controls the second data processing modules of the first sampling channel and the second sampling channel respectively to process the first sampled data to obtain a first starting phase value, including:
[0018] After performing linear interpolation on the first sampled data, the rising zero-crossing point is extracted;
[0019] The first initial phase value is obtained by calculating based on the zero-crossing point.
[0020] In some embodiments, the first data processing module controls the second data processing modules of the first sampling channel and the second sampling channel respectively to process the second sampled data to obtain a second starting phase value, including:
[0021] Perform a Hilbert transform on the second sampled data and obtain the second phase value in the complex domain;
[0022] The second phase value is obtained by unwinding the second phase value.
[0023] In some implementations, the first data processing module calculates a delay parameter based on the first phase difference and the second phase difference, including:
[0024] The delay parameter is calculated using a defuzzification algorithm based on the first phase difference and the second phase difference.
[0025] In some implementations, it also includes:
[0026] The first data processing module presets a maximum expected time delay parameter;
[0027] Establish a system of linear equations that includes the delay parameter, the first fuzzy number, and the second fuzzy number, wherein the first fuzzy number and the second fuzzy number constitute an integer pair of fuzzy numbers;
[0028] The integer search range of the first fuzzy number and the second fuzzy number is determined based on the preset maximum expected time delay parameter;
[0029] Within the integer search range, traverse all pairs of fuzzy integers;
[0030] For each pair of fuzzy integers, two estimated values of delay parameters are calculated based on the linear equations of the first fuzzy number and the second fuzzy number.
[0031] And determine the residual between the two estimated values of the delay parameter;
[0032] Select the pair of fuzzy numbers that minimizes the residual between the estimated values of the two delay parameters, and determine the first target fuzzy number and the second target fuzzy number.
[0033] Furthermore, the first target fuzzy number and the second target fuzzy number are substituted into a system of linear equations containing the delay parameter, the first fuzzy number, and the second fuzzy number to solve for and obtain the delay parameter.
[0034] In some implementations, the first data processing module calculates the delay parameter based on the first phase difference and the second phase difference, and further includes:
[0035] Based on the frequency points of the first and second calibration signals and the corresponding first and second phase differences, a system of equations is constructed to obtain the slope of the frequency points, i.e., the delay parameter.
[0036] In some implementations, the first data processing module controls the second data processing module corresponding to the first sampling channel to load the delay parameter to complete data synchronization and align with the data of the second sampling channel;
[0037] And / or, the first data processing module controls the second data processing module corresponding to the second sampling channel to load the delay parameter to complete data synchronization and align with the data of the first sampling channel.
[0038] Secondly, the present invention provides an oscilloscope, the oscilloscope including a first sampling channel, a second sampling channel and a first data processing module, the first sampling channel and the second sampling channel each including an analog-to-digital conversion module and a second data processing module, the oscilloscope performing a multi-channel data synchronous acquisition method as described in any of the foregoing embodiments.
[0039] Thirdly, the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed, can implement the multi-channel data synchronous acquisition method as described in any of the foregoing embodiments.
[0040] This application provides a multi-channel data synchronous acquisition method and oscilloscope. By employing a dual-frequency calibration scheme, it utilizes calibration signals from two coprime frequencies to perform two independent phase difference measurements, fundamentally eliminating the periodic ambiguity problem present in single-frequency measurements. This allows for the unique and accurate calculation of picosecond-level delay parameters between channels, significantly improving calibration accuracy and reliability. Simultaneously, the entire calibration process is fully automated by an internal module, effectively compensating for individual delay differences caused by hardware manufacturing, temperature variations, and other factors, ensuring measurement consistency across sampling channels, and achieving high-precision built-in self-calibration performance. Attached Figure Description
[0041] Figure 1 This is a schematic diagram of the structure of an oscilloscope according to one embodiment of the present invention;
[0042] Figure 2 This is a flowchart illustrating a multi-channel data synchronous acquisition method according to an embodiment of the present invention.
[0043] Figure 3This is a flowchart illustrating another embodiment of the multi-channel data synchronous acquisition method provided by the present invention;
[0044] Figure 4 This is a flowchart illustrating another embodiment of the multi-channel data synchronous acquisition method provided by the present invention;
[0045] Figure 5 This is a flowchart illustrating another embodiment of the multi-channel data synchronous acquisition method provided by the present invention;
[0046] Figure 6 This is a flowchart illustrating another embodiment of the multi-channel data synchronous acquisition method provided by the present invention;
[0047] Figure 7 This is a flowchart illustrating another embodiment of the multi-channel data synchronous acquisition method provided by the present invention.
[0048] In the diagram: oscilloscope 1, first sampling channel 10, second sampling channel 20, first data processing module 30, analog-to-digital conversion module 40, second data processing module 50. Detailed Implementation
[0049] To make the technical solution and beneficial effects of the present invention more apparent and understandable, a detailed description is provided below by listing specific embodiments. The accompanying drawings are not necessarily drawn to scale, and local features may be enlarged or reduced to more clearly show the details of the local features; unless otherwise defined, the technical and scientific terms used herein have the same meanings as those in the technical field to which this application pertains.
[0050] This disclosure of embodiments is not exhaustive, but merely illustrative of some embodiments, and is not intended to limit the scope of protection of this disclosure. Unless contradictory, each step in a particular embodiment can be implemented as an independent embodiment, and the steps can be arbitrarily combined. For example, a solution after removing some steps in a particular embodiment can also be implemented as an independent embodiment, and the order of the steps in a particular embodiment can be arbitrarily interchanged. Furthermore, the optional implementation methods in a particular embodiment can be arbitrarily combined; moreover, the embodiments can be arbitrarily combined, for example, some or all steps of different embodiments can be arbitrarily combined, and a particular embodiment can be arbitrarily combined with the optional implementation methods of other embodiments.
[0051] In each of the disclosed embodiments, unless otherwise specified or in case of logical conflict, the terminology and / or descriptions of the embodiments are consistent and can be referenced by each other. Technical features in different embodiments can be combined to form new embodiments based on their inherent logical relationships.
[0052] The terminology used in the embodiments of this disclosure is for the purpose of describing particular embodiments only and is not intended to limit the scope of this disclosure.
[0053] Furthermore, each element, each row, or each column in the table of this disclosure can be implemented as an independent implementation, and any combination of any element, any row, or any column can also be implemented as an independent implementation.
[0054] In some implementations, each analog channel corresponds to a sampling system, and each sampling system includes an analog front-end, an ADC, a sampling clock, and an FPGA, independently completing the sampling, storage, and necessary data processing for the channel. The processed data from the FPGAs of multiple channels are aggregated to the common FPGA of the oscilloscope for triggering, display, and other processing.
[0055] In oscilloscopes with multi-channel data sampling, synchronous calibration between multiple channels becomes a problem that must be solved. Otherwise, there will be uncertain delay differences between the data sampled by the oscilloscope, which will seriously affect the oscilloscope's observation and measurement of multi-channel signals.
[0056] Figure 1 This is a schematic diagram of the structure of an oscilloscope according to one embodiment of the present invention.
[0057] Figure 2 This is a flowchart illustrating a multi-channel data synchronous acquisition method according to an embodiment of the present invention.
[0058] Firstly, this application provides a multi-channel data synchronous acquisition method for an oscilloscope 1, such as... Figure 1 and Figure 2 As shown, the oscilloscope 1 includes a first sampling channel 10, a second sampling channel 20, and a first data processing module 30. The first sampling channel 10 and the second sampling channel 20 each include an analog-to-digital conversion module 40 and a second data processing module 50. The first sampling channel 10 and the second sampling channel 20 perform synchronous acquisition and alignment of channel data by receiving calibration signals. The calibration signals include a first calibration signal and a second calibration signal with coprime frequencies. The method includes:
[0059] In step S1, the first data processing module 30 controls the analog-to-digital conversion module 40 of the first sampling channel 10 and the second sampling channel 20 to acquire the first calibration signal and obtain the first sampling data. The first data processing module 30 controls the second data processing module 50 of the first sampling channel and the second sampling channel 20 to process the first sampling data to obtain the first starting phase value, and calculates the first phase difference value based on the first starting phase value of the first sampling channel 10 and the second sampling channel 20.
[0060] In step S2, the first data processing module 30 controls the analog-to-digital conversion module 40 of the first sampling channel 10 and the second sampling channel 20 to acquire the second calibration signal and obtain the second sampling data. The first data processing module 30 controls the second data processing module 50 of the first sampling channel and the second sampling channel 20 to process the second sampling data to obtain the second starting phase value, and calculates the second phase difference value based on the second starting phase value of the first sampling channel 10 and the second sampling channel 20.
[0061] In step S3, the first data processing module 30 calculates the delay parameter based on the first phase difference and the second phase difference, and completes the data synchronization of the first sampling channel 10 and the second sampling channel 20 based on the delay parameter.
[0062] This implementation employs a dual-frequency calibration scheme, utilizing two coprime calibration signals to perform two independent phase difference measurements. This fundamentally eliminates the 2π periodic ambiguity problem present in single-frequency measurements, enabling the unique and precise calculation of picosecond-level delay parameters between channels, significantly improving calibration accuracy and reliability. Simultaneously, the entire calibration process is fully automated by an internal module, effectively compensating for individual delay differences caused by hardware manufacturing, temperature variations, and other factors, ensuring measurement consistency across sampling channels and achieving high-precision self-calibration performance.
[0063] Here, oscilloscope 1 is a digital oscilloscope board, and each digital oscilloscope board can have multiple first sampling channels 10 and second sampling channels 20; or, one digital oscilloscope board has a first sampling channel 10, and another digital oscilloscope board has a second sampling channel 20. Each first sampling channel 10 and second sampling channel 20 can be used to connect an external oscilloscope device.
[0064] In one possible implementation, the external oscilloscope device includes an oscilloscope probe.
[0065] In one possible implementation, an external device for the oscilloscope can be used to probe a signal and transmit the probed signal to the oscilloscope 1 via an electrical connection (such as an analog input port) between the oscilloscope and the oscilloscope.
[0066] In one possible implementation, the oscilloscope 1 may also include an analog front-end board, etc., for sending the detected signal to the analog-to-digital conversion module 40. The analog front-end can be used to perform analog signal processing on the received signal, such as signal amplification and signal attenuation.
[0067] The analog-to-digital conversion module 40 samples the signal processed by the analog front-end, converting the analog signal into digital signals, namely first sampled data and second sampled data, and sends the first sampled data and second sampled data to the second data processing unit 50. The second data processing unit 50 processes the first sampled data and second sampled data, extracts the first starting phase and second starting phase, and sends the first starting phase and second starting phase to the first data processing module 30 in the oscilloscope 1. The analog-to-digital conversion module 40 may include an ADC (Analog-to-Digital Converter), etc.
[0068] Here, the second data processing unit 50 is used to process the first sampled data, and can perform at least one of the following: digital filtering;
[0069] Data packets for transport protocols.
[0070] In one possible implementation, the first data processing module 30 is used to process, display, and trigger data acquired by the first sampling channel 10 and the second sampling channel 20.
[0071] In one possible implementation, the first data processing module 30 may be implemented by an FPGA, but is not limited thereto.
[0072] In one possible implementation, the second data processing module 20 can be implemented by an FPGA, but is not limited thereto.
[0073] In one possible implementation, the analog-to-digital conversion module 40 can send the first sampled data to the second data processing unit 50 via a data bus. The data bus may include: an LVDS data bus, a JESD204B data bus, etc.
[0074] In one possible implementation, the analog-to-digital conversion module 40 does not have a data buffer. Therefore, the analog-to-digital conversion module 40 is triggered to sample, and the first sampled data or the second sampled data is transmitted synchronously.
[0075] In this embodiment, the first calibration signal and the second calibration signal have coprime frequencies. Specifically, in the overlapping frequency region of the first sampling channel 10 and the second sampling channel 20, the first calibration signal and the second calibration signal with coprime frequencies are generated to achieve the calibration requirements of low harmonics, low phase noise, accurate frequency, and stable amplitude. This requires the deployment of a source capable of generating accurate and stable single-tone signals.
[0076] In one possible implementation, the signal source can be a dedicated signal generator, for example, by connecting an external signal generator to the oscilloscope probe 1 to receive a calibration signal generated by the signal generator.
[0077] In one possible implementation, the signal source can be integrated into the oscilloscope 1. For example, a calibration signal (first calibration signal / second calibration signal) is generated by the crystal oscillator circuit integrated on the oscilloscope 1 and sent to the first sampling channel 10 and the second sampling channel 20 through the internal circuit.
[0078] Figure 3 This is a flowchart illustrating another embodiment of the multi-channel data synchronous acquisition method provided by the present invention.
[0079] In some implementations, such as Figure 3 As shown, the first data processing module 30 controls the second data processing module 50 of the first sampling channel and the second sampling channel 20 respectively to process the first sampled data to obtain the first starting phase value, including:
[0080] Step S31: Perform Hilbert transform on the first sampled data and obtain the first phase value in the complex domain;
[0081] Step S32: Perform unwinding calculation on the first phase value to obtain the first starting phase value.
[0082] This implementation first performs a Hilbert transform on the sampled data to upscale the one-dimensional real signal to the complex domain, enabling precise extraction of its instantaneous phase. Then, through phase unwinding, the wound phase is restored to a continuous linear curve. This combined method not only greatly ensures the fidelity of phase measurement but also provides a stable and unambiguous data foundation for subsequent precise calculation of the signal's initial phase via linear fitting, thereby improving the accuracy of the d-calibration results.
[0083] Figure 4 This is a flowchart illustrating another embodiment of the multi-channel data synchronous acquisition method provided by the present invention.
[0084] In some implementations, such as Figure 4 As shown, the first data processing module 30 controls the second data processing module 50 of the first sampling channel and the second sampling channel 20 respectively to process the first sampled data to obtain the first starting phase value, including:
[0085] Step S41: Preset a sampling time window in the first data processing module 30;
[0086] Step S42: Perform a fast Fourier transform on the first sampled data to obtain the first spectrum. Each spectral point of the first spectrum contains the amplitude and phase of the corresponding frequency.
[0087] Step S43: Obtain the spectrum points corresponding to the first calibration signal, perform complex domain transformation and extract the phase value, the phase value corresponds to the phase of the first sampled data at the center point of the preset sampling time window;
[0088] Step S44: Perform phase correction based on the total duration of the sampling time window to obtain the first initial phase value.
[0089] Figure 5 This is a flowchart illustrating another embodiment of the multi-channel data synchronous acquisition method provided by the present invention.
[0090] In some implementations, such as Figure 5 As shown, the first data processing module 30 controls the second data processing module 50 of the first sampling channel and the second sampling channel 20 respectively to process the first sampled data to obtain the first starting phase value, including:
[0091] Step S51: After performing linear interpolation on the first sampled data, extract the rising zero-crossing point, that is, the point where the signal changes from a negative value to a positive value;
[0092] Step S52: Calculate and obtain the first initial phase value based on the zero-crossing point of the rising edge.
[0093] Figure 6 This is a flowchart illustrating another embodiment of the multi-channel data synchronous acquisition method provided by the present invention.
[0094] In some implementations, such as Figure 6 As shown, the first data processing module 30 controls the second data processing module 50 of the first sampling channel and the second sampling channel 20 respectively to process the second sampled data to obtain the second starting phase value, including:
[0095] Step S61: Perform Hilbert transform on the second sampled data and obtain the second phase value in the complex domain;
[0096] Step S62: Perform unwinding calculation on the second phase value to obtain the second starting phase value.
[0097] In some embodiments, the first data processing module 30 calculates and obtains the delay parameter between the first sampling channel 10 and the second sampling channel 20 based on the first phase difference and the second phase difference, and further includes:
[0098] Based on the first phase difference and the second phase difference, the delay parameters of the first sampling channel 10 and the second sampling channel 20 are calculated using a fuzzy algorithm.
[0099] This implementation uses a defuzzification algorithm to process the phase difference values measured at two different frequencies, eliminating the inherent 2π periodic ambiguity problem in single-frequency phase measurement. This ensures that the final calculated inter-channel delay parameter is unique and correct, rather than one of multiple possible values, thus improving the accuracy and reliability of the calibration results. Furthermore, it expands the range of time delays that can be precisely calibrated, enhancing the applicability and robustness of the entire system.
[0100] Figure 7 This is a flowchart illustrating another embodiment of the multi-channel data synchronous acquisition method provided by the present invention.
[0101] In some implementations, such as Figure 7 As shown, it also includes:
[0102] Step S71: The first data processing module 30 presets the maximum expected time delay parameter;
[0103] Step S72: Establish a system of linear equations containing a delay parameter, a first fuzzy number, and a second fuzzy number, wherein the first fuzzy number and the second fuzzy number constitute an integer pair of fuzzy numbers;
[0104] Step S73: Determine the integer search range of the first fuzzy number and the second fuzzy number based on the preset maximum expected time delay parameter;
[0105] Step S74: Within the integer search range, traverse all pairs of fuzzy integers;
[0106] Step S75: For each pair of fuzzy integers, calculate the estimated values of two delay parameters based on the linear equations of the first and second fuzzy numbers.
[0107] Step S76, and determine the residuals of the two delay parameter estimates;
[0108] Step S77: Select the pair of fuzzy integers that minimizes the residual between the estimated values of the two delay parameters, and determine the first target fuzzy number and the second target fuzzy number;
[0109] And in step S78, the first target fuzzy number and the second target fuzzy number are substituted into a system of linear equations containing the delay parameter, the first fuzzy number and the second fuzzy number, and the delay parameter is obtained by solving the system.
[0110] For example, in this embodiment, the first data processing module 30 controls the signal source to generate a first calibration signal within the overlapping frequency band of the first sampling channel 10 and the second sampling channel 20, with a frequency of =100MHz, the first data processing module 30 controls the first sampling channel 10 and the second sampling channel 20 to acquire the first sampling data of the first calibration signal, and the second data processing module 20 processes the first sampling data to obtain the first phase difference value. Calculate and obtain information about Delay parameters for The specific formula is as follows:
[0111] ;
[0112] At this time, the delay parameter for This is the apparent delay, because the period of a 100MHz signal is T1 = 1 / f1 = 10ns. The actual delay could be 0.5ns, 10.5ns (1*T1 + 0.5ns), or 20.5ns (2*T1 + 0.5ns), etc.
[0113] The first data processing module 30 controls the signal source to generate a second calibration signal, coprime to the frequency of the first calibration signal, within the overlapping frequency band of the first sampling channel 10 and the second sampling channel 20, with a frequency of [missing information]. =99MHz, obtain the second phase difference value Calculate and obtain information about Delay parameters for Construct a system of linear equations:
[0114] = ;
[0115] = ;
[0116] in and The first calibration signal is respectively Second calibration signal The number of fuzzy periods, This is the delay parameter.
[0117] Based on the maximum expected time delay parameters of the hardware design Sure Reasonable physical range .Depend on The expected range and equations (1-1) and (1-2) are derived. and Possible value range and Within this expected range, iterate through all possible pairs of integers. Specifically, construct fuzzy integer pairs:
[0118] based on :0.5ns,10.5ns,20.5ns,……
[0119] based on :10.05ns,20.15ns,30.25ns,……
[0120] The first data processing module 30 calculates and selects the fuzzy integer pair that minimizes the residuals of the estimated values of the two delay parameters, namely 10.5 ns and 10.05 ns. At this point, the first sampling channel 10 is used as the calibration reference channel. =1, to obtain the delay parameter It is 10.5ns.
[0121] In some embodiments, the first data processing module 30 calculates the delay parameter based on the first phase difference and the second phase difference, and further includes:
[0122] Based on the frequency points of the first and second calibration signals and the corresponding first and second phase differences, a system of equations is constructed to obtain the slope of the frequency points, i.e., the delay parameter.
[0123] In some implementations, the first data processing module 30 controls the second data processing module 50 corresponding to the first sampling channel 10 to load delay parameters to complete data calibration and align with the data of the second sampling channel 20.
[0124] In some implementations, the first data processing module 30 controls the second data processing module 50 corresponding to the second sampling channel 20 to load delay parameters to complete data calibration and align with the data of the first sampling channel 10.
[0125] Secondly, this application provides an oscilloscope 1, which includes a first sampling channel 10, a second sampling channel 20, and a first data processing module 30. The first sampling channel 10 and the second sampling channel 20 each include an analog-to-digital conversion module 40 and a second data processing module 50. The oscilloscope 1 performs a multi-channel data synchronous acquisition method as described in any of the foregoing embodiments.
[0126] In some possible implementations, the first sampling channel 10 and / or the second sampling channel 20 are mounted on multiple oscilloscope boards 1.
[0127] In some implementations, multiple first sampling channels 10 and / or second sampling channels 20 use the JESD204B protocol for data transmission.
[0128] Thirdly, this application provides a computer-readable storage medium having a computer program stored thereon, which, when executed, enables the implementation of a multi-channel data synchronous acquisition method as described in any of the foregoing embodiments.
[0129] This application provides a multi-channel data synchronous acquisition method, which is applicable to the synchronous acquisition of data between multiple sampling channels of a single oscilloscope board, as well as the synchronous acquisition of data between multiple sampling channels of multiple oscilloscope boards. It can also adaptively simulate hardware link delays caused by external devices such as front-end boards and external clock source boards, and has wide applicability.
[0130] Other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This disclosure is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein.
[0131] It should be understood that the present invention is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope.
Claims
1. A multi-channel data synchronous acquisition method, characterized in that, For an oscilloscope, the oscilloscope includes a first sampling channel, a second sampling channel, and a first data processing module. The first and second sampling channels each include an analog-to-digital conversion module and a second data processing module. The first and second sampling channels synchronize and align channel data acquisition by receiving calibration signals. The calibration signals include a first calibration signal and a second calibration signal with coprime frequencies. The method includes: The first data processing module controls the analog-to-digital conversion modules of the first sampling channel and the second sampling channel to acquire the first calibration signal and obtain the first sampling data. The first data processing module controls the second data processing modules of the first sampling channel and the second sampling channel to process the first sampling data to obtain the first starting phase value, and calculates the first phase difference value based on the first starting phase value of the first sampling channel and the second sampling channel. The first data processing module controls the analog-to-digital conversion modules of the first sampling channel and the second sampling channel to acquire the second calibration signal and obtain the second sampling data. The first data processing module controls the second data processing modules of the first sampling channel and the second sampling channel to process the second sampling data to obtain the second starting phase value, and calculates the second phase difference based on the second starting phase value of the first sampling channel and the second sampling channel. The first data processing module calculates a delay parameter based on the first phase difference and the second phase difference, and completes data synchronization between the first sampling channel and the second sampling channel based on the delay parameter.
2. The multi-channel data synchronous acquisition method according to claim 1, characterized in that, The first data processing module controls the second data processing modules of the first sampling channel and the second sampling channel respectively to process the first sampled data to obtain the first starting phase value, including: Perform a Hilbert transform on the first sampled data and obtain the first phase value in the complex domain; The first initial phase value is obtained by performing unwinding calculation on the first phase value.
3. The multi-channel data synchronous acquisition method according to claim 1, characterized in that, The first data processing module controls the second data processing modules of the first sampling channel and the second sampling channel respectively to process the first sampled data to obtain the first starting phase value, including: A preset sampling time window is set in the first data processing module; The first sampled data is subjected to a fast Fourier transform to obtain a first spectrum, and each spectral point of the first spectrum contains the amplitude and phase of the corresponding frequency. Obtain the spectral points corresponding to the first calibration signal, perform complex domain transformation and extract the phase value, the phase value corresponding to the phase of the first sampled data at the center point of the preset sampling time window; The first initial phase value is obtained by performing phase correction based on the total duration of the sampling time window.
4. The multi-channel data synchronous acquisition method according to claim 1, characterized in that, The first data processing module controls the second data processing modules of the first sampling channel and the second sampling channel respectively to process the first sampled data to obtain the first starting phase value, including: After performing linear interpolation on the first sampled data, the rising zero-crossing point is extracted; The first initial phase value is obtained by calculating based on the zero-crossing point.
5. The multi-channel data synchronous acquisition method according to claim 2, characterized in that, The first data processing module controls the second data processing modules of the first sampling channel and the second sampling channel respectively to process the second sampled data to obtain the second starting phase value, including: Perform a Hilbert transform on the second sampled data and obtain the second phase value in the complex domain; The second phase value is obtained by unwinding the second phase value.
6. The multi-channel data synchronous acquisition method according to any one of claims 2 to 5, characterized in that, The first data processing module calculates the delay parameter based on the first phase difference and the second phase difference, including: The delay parameter is calculated using a defuzzification algorithm based on the first phase difference and the second phase difference.
7. The multi-channel data synchronous acquisition method according to claim 6, characterized in that, Also includes: The first data processing module presets a maximum expected time delay parameter; Establish a system of linear equations that includes the delay parameter, the first fuzzy number, and the second fuzzy number, wherein the first fuzzy number and the second fuzzy number constitute an integer pair of fuzzy numbers; The integer search range of the first fuzzy number and the second fuzzy number is determined based on the preset maximum expected time delay parameter; Within the integer search range, traverse all pairs of fuzzy integers; For each pair of fuzzy integers, two estimated values of delay parameters are calculated based on the linear equations of the first fuzzy number and the second fuzzy number. And determine the residual between the two estimated values of the delay parameter; Select the pair of fuzzy numbers that minimizes the residual between the estimated values of the two delay parameters, and determine the first target fuzzy number and the second target fuzzy number. as well as Substitute the first target fuzzy number and the second target fuzzy number into a system of linear equations containing the delay parameter, the first fuzzy number, and the second fuzzy number, and solve to obtain the delay parameter.
8. The multi-channel data synchronous acquisition method according to any one of claims 2 to 5, characterized in that: The first data processing module calculates the delay parameter based on the first phase difference and the second phase difference, and further includes: Based on the frequency points of the first and second calibration signals and the corresponding first and second phase differences, a system of equations is constructed to obtain the slope of the frequency points, i.e., the delay parameter.
9. The multi-channel data synchronous acquisition method according to claim 1, characterized in that, The first data processing module controls the second data processing module corresponding to the first sampling channel to load the delay parameter to complete data synchronization and align with the data of the second sampling channel; and / or The first data processing module controls the second data processing module corresponding to the second sampling channel to load the delay parameter to complete data synchronization and align with the data of the first sampling channel.
10. An oscilloscope, characterized in that, The oscilloscope includes a first sampling channel, a second sampling channel, and a first data processing module. The first sampling channel and the second sampling channel each include an analog-to-digital conversion module and a second data processing module. The oscilloscope performs the multi-channel data synchronous acquisition method as described in any one of claims 1 to 9.