High-repetition-frequency X-ray free electron laser pulse measuring system

Abstract

The invention discloses a high-repetition-frequency X-ray free electron laser pulse measurement system which comprises an X-ray detection module, a first signal processing module, a second signal processing module and an acquisition display module. The X-ray detection module is used for receiving irradiation of X-ray free electron laser pulses and converting optical signals into current pulse signals through a photodiode. The first signal processing module is used for filtering and amplifying the current pulse signal and completing current-voltage conversion so as to generate a voltage pulse analog signal. And the second signal processing module is used for carrying out analog-to-digital conversion and pulse feature extraction on the voltage pulse analog signal so as to generate a voltage pulse digital signal and a corresponding pulse feature value. And the acquisition display module is used for acquiring and displaying the voltage pulse digital signal and the corresponding pulse characteristic value. The system can track and measure high-repetition-frequency X-ray pulses, large-dynamic-range accurate measurement of signal intensity is achieved, and technical support is provided for beam line diagnosis and incident light calibration.

Description

Technical Field

[0001] This invention relates to the field of laser pulse measurement technology, and in particular to a high repetition rate X-ray free electron laser pulse measurement system. Background Technology

[0002] The rapidly developing X-ray free-electron laser (XLE) has provided an advanced platform for forward-looking research and technological innovation in many fields such as physics, chemistry, and energy. Among them, the XLE with high repetition rate characteristics has significant advantages. It can accumulate a large amount of data in a short time, thereby completing high spatiotemporal resolution experiments. It is an advanced representative of this type of device and represents the future direction of development.

[0003] In the construction and operation of X-ray free-electron laser (XLEX) devices, the XLEX single-pulse energy is a critical parameter. Accurate measurement of this parameter is crucial for device commissioning and the smooth conduct of experiments. Photodiodes, as a commonly used tool in X-ray measurement, play a vital role in advanced light sources such as synchrotron radiation and XLEX devices. Currently, in domestically developed synchrotron radiation sources, photodiodes are widely used for X-ray pulse energy measurement. There are two main methods for measuring their output current signal: one is direct measurement using a picoammeter; the other is amplification and conversion into a voltage signal, followed by amplitude measurement using a voltage-to-frequency conversion module and a counter.

[0004] However, the two types of measurement systems mentioned above have significant shortcomings in X-ray free electron laser devices. They cannot measure individual X-ray pulses one by one, nor can they acquire pulse waveforms, making it difficult to monitor the response state of photodiodes. Currently, in X-ray free electron laser devices still in the early stages of development in China, oscilloscopes or digitizers are typically used to directly acquire the pulse signal waveform of the photodiode, and then the pulse energy is measured by integrating the waveform. However, for the measurement of high-repetition-rate X-ray free electron laser pulses, the data transmission speed of oscilloscopes is limited, which is not conducive to real-time monitoring of pulse energy changes. The sensitivity and measurement range of digitizers are limited, making it difficult to meet the requirements for large dynamic range measurement of free electron laser pulses with unstable pulse energy. Summary of the Invention

[0005] The purpose of this invention is to provide a high repetition rate X-ray free electron laser pulse measurement system. This system integrates advanced photoelectric signal conversion technology and digital processing technology, enabling efficient processing of weak pulse signals output by photodiodes. It also incorporates an adaptive gain adjustment mechanism that automatically adjusts the amplification factor based on the intensity of the input pulse signal. Furthermore, a real-time signal processing platform is built based on a high-speed field-programmable gate array (FPGA). Utilizing the parallel processing capabilities and high-speed computing characteristics of the FPGA, real-time acquisition, rapid transmission, and online analysis of pulse signals are achieved. This solves the technical problems of existing measurement systems in high repetition rate X-ray free electron laser pulse measurement, such as slow signal acquisition speed, low processing accuracy leading to inaccurate acquisition of pulse energy and waveform information, limited measurement range, insufficient sensitivity leading to difficulty in achieving accurate measurement over a large dynamic range, and slow data transmission rate and large processing delay leading to the inability to acquire pulse energy changes in real time.

[0006] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution:

[0007] This invention provides a high repetition rate X-ray free electron laser pulse measurement system, which includes: an X-ray detection module, a first signal processing module, a second signal processing module, and an acquisition and display module;

[0008] The X-ray detection module is used to receive X-ray free electron laser pulses and convert the optical signal into a current pulse signal through a photodiode.

[0009] The input terminal of the first signal processing module is connected to the output terminal of the X-ray detection module, and is used to filter and amplify the current pulse signal and complete the current-to-voltage conversion to generate a voltage pulse analog signal.

[0010] The input terminal of the second signal processing module is connected to the output terminal of the first signal processing module, and is used to perform analog-to-digital conversion and pulse feature extraction on the voltage pulse analog signal to generate a voltage pulse digital signal and its corresponding pulse feature value;

[0011] The input terminal of the acquisition and display module is connected to the output terminal of the second signal processing module, and is used to acquire and display the voltage pulse digital signal and its corresponding pulse characteristic value.

[0012] In one embodiment of the present invention, the X-ray free-electron laser pulse is generated by a free-electron laser device and has a pulse width on the order of hundreds of femtoseconds and a single energy characteristic.

[0013] In one embodiment of the present invention, the first signal processing module includes a gating switch unit and a signal amplification unit;

[0014] The input terminal of the gating switch unit is connected to the output terminal of the X-ray detection module, and the output terminal is connected to the input terminal of the signal amplification unit. It is used to automatically select the corresponding signal path according to the signal strength of the current pulse signal output by the X-ray detection module.

[0015] The input terminal of the signal amplification unit is connected to the output terminal of the gating switch unit, and the output terminal is connected to the input terminal of the second signal processing module. It is used to amplify the current pulse signal output by the X-ray detection module and complete the current-voltage conversion to generate the voltage pulse analog signal.

[0016] In one embodiment of the present invention, the gating switch unit includes a single-pole multi-throw switch;

[0017] The input terminal of the single-pole multi-throw switch is connected to the output terminal of the X-ray detection module, and each output terminal of the single-pole multi-throw switch is connected to each input terminal of the signal amplification unit, respectively, for automatically selecting the corresponding signal path according to the signal strength of the current pulse signal output by the X-ray detection module.

[0018] In one embodiment of the present invention, the signal amplification unit includes multiple amplifiers with different amplification factors;

[0019] The input terminals of the plurality of amplifiers with different multiples are respectively connected to the corresponding output terminals of the gating switch unit, and the output terminals are connected to the input terminal of the second signal processing module. They are used to amplify the current pulse signal output by the X-ray detection module and complete the current-to-voltage conversion to generate the voltage pulse analog signal.

[0020] In one embodiment of the present invention, the first signal processing module further includes a filtering unit;

[0021] The input terminal of the filtering unit is connected to the output terminal of the X-ray detection module, and the output terminal is connected to the input terminal of the gating switch unit. It is used to filter the current pulse signal output by the X-ray detection module to remove noise interference.

[0022] In one embodiment of the present invention, the second signal processing module includes an analog-to-digital conversion unit and a digital signal processing unit;

[0023] The input terminal of the analog-to-digital converter is connected to the output terminal of the first signal processing module, and the output terminal is connected to the input terminal of the digital signal processing unit, for converting the voltage pulse analog signal into a voltage pulse digital signal;

[0024] The output of the digital signal processing unit is connected to the input of the acquisition and display module, and is used to extract pulse features from the voltage pulse digital signal to obtain pulse feature values ​​of the voltage pulse digital signal. The pulse feature values ​​include pulse charge integral, pulse height, and pulse shape.

[0025] In one embodiment of the present invention, the connecting cables between the X-ray detection module and the first signal processing module, and between the first signal processing module and the second signal processing module, are coaxial cables to shield against noise interference.

[0026] In one embodiment of the present invention, the second signal processing module adopts a desktop terminal-based structural design, which enables it to flexibly switch between multiple long-distance measurement points according to actual measurement needs.

[0027] In one embodiment of the present invention, the second signal processing module performs analog-to-digital conversion and pulse feature extraction on the voltage pulse analog signal through a field-programmable gate array to achieve real-time tracking and measurement of the characteristics of high repetition rate X-ray free electron laser pulses.

[0028] In summary, the high-repetition-rate X-ray free-electron laser pulse measurement system provided by this invention includes: an X-ray detection module, a first signal processing module, a second signal processing module, and an acquisition and display module. The X-ray detection module receives X-ray free-electron laser pulse irradiation and converts the optical signal into a current pulse signal via a photodiode. The input terminal of the first signal processing module is connected to the output terminal of the X-ray detection module, and it filters and amplifies the current pulse signal and performs current-to-voltage conversion to generate a voltage pulse analog signal. The input terminal of the second signal processing module is connected to the output terminal of the first signal processing module, and it performs analog-to-digital conversion and pulse feature extraction on the voltage pulse analog signal to generate a voltage pulse digital signal and its corresponding pulse feature values. The input terminal of the acquisition and display module is connected to the output terminal of the second signal processing module, and it acquires and displays the voltage pulse digital signal and its corresponding pulse feature values. This system possesses the capability to track and measure high-repetition-rate X-ray free-electron laser pulses, enabling precise measurement of signal intensity over a large dynamic range. Simultaneously, it can acquire and display the original waveform, pulse characteristic values, and variation trends of the pulse signal according to actual needs, providing robust technical support for beamline diagnostics on high-repetition-rate X-ray free-electron laser devices and incident light calibration tasks at experimental stations. Of course, implementing any product of this invention does not necessarily require achieving all of the advantages described above simultaneously. Attached Figure Description

[0029] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a structural block diagram of a high repetition rate X-ray free electron laser pulse measurement system provided for an exemplary embodiment of this application.

[0031] Figure 2 This is a structural block diagram of a first signal processing module provided for an exemplary embodiment of this application.

[0032] Figure 3 This is a structural block diagram of a second signal processing module provided for an exemplary embodiment of this application.

[0033] The attached figures are labeled as follows:

[0034] 100 X-ray detection modules

[0035] 200 First Signal Processing Module

[0036] 300 Second Signal Processing Module

[0037] 400 Acquisition and Display Module

[0038] 210 Filter Unit

[0039] 220 Selector Switch Unit

[0040] 230 Signal Amplification Unit

[0041] 310 Analog-to-Digital Conversion Unit

[0042] 320 Digital Signal Processing Unit Detailed Implementation

[0043] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, unless otherwise specified, the following embodiments and features described therein can be combined with each other.

[0044] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0045] In the following description, numerous details are explored to provide a more thorough explanation of embodiments of the invention. However, it will be apparent to those skilled in the art that embodiments of the invention may be practiced without these specific details. In other embodiments, publicly known structures and devices are shown in block diagram form rather than in detail to avoid obscuring embodiments of the invention.

[0046] To address the technical challenges faced by existing measurement systems in measuring high-repetition-rate X-ray free-electron laser pulses, such as slow signal acquisition speed, low processing accuracy leading to inaccurate pulse energy and waveform information, limited measurement range and insufficient sensitivity hindering accurate measurement over a large dynamic range, and slow data transmission rate and large processing delay preventing real-time acquisition of pulse energy changes, this invention proposes a high-repetition-rate X-ray free-electron laser pulse measurement system. This system integrates advanced photoelectric signal conversion technology and digital processing technology, enabling efficient processing of weak pulse signals output by photodiodes. Furthermore, an adaptive gain adjustment mechanism is designed to automatically adjust the amplification factor based on the intensity of the input pulse signal. In addition, a real-time signal processing platform is constructed based on a high-speed field-programmable gate array (FPGA), utilizing the parallel processing capabilities and high-speed computing characteristics of the FPGA to achieve real-time acquisition, rapid transmission, and accurate online analysis of the pulse signal.

[0047] It should be noted that the X-ray free-electron laser pulses referred to are a type of X-ray pulse generated using free-electron laser technology, possessing ultra-short duration, ultra-high intensity, and high coherence characteristics. The X-ray pulse repetition frequency refers to the specific number of X-ray pulses generated per unit time interval. For example, a repetition frequency of 1 MHz means that 1 million X-ray pulses can be generated per second. Furthermore, the dynamic range refers to the ratio between the maximum and minimum signal intensity that the measurement system can simultaneously and accurately measure. For example, if the dynamic range of a measurement system is 100, it indicates that the maximum signal intensity that the system can accurately measure is 100 times the minimum signal intensity.

[0048] In one exemplary embodiment of this application, please refer to Figure 1As shown, the high repetition rate X-ray free electron laser pulse measurement system includes: an X-ray detection module 100, a first signal processing module 200, a second signal processing module 300, and an acquisition and display module 400. The X-ray detection module 100 receives X-ray free electron laser pulses and converts the light signal into a current pulse signal via a photodiode. The input terminal of the first signal processing module 200 is connected to the output terminal of the X-ray detection module, and it filters and amplifies the current pulse signal and performs current-to-voltage conversion to generate a voltage pulse analog signal. The input terminal of the second signal processing module 300 is connected to the output terminal of the first signal processing module, and it performs analog-to-digital conversion and pulse feature extraction on the voltage pulse analog signal to generate a voltage pulse digital signal and its corresponding pulse feature values. The input terminal of the acquisition and display module 400 is connected to the output terminal of the second signal processing module, and it acquires and displays the voltage pulse digital signal and its corresponding pulse feature values.

[0049] It should be noted that in this embodiment, the X-ray free-electron laser pulse is generated by a free-electron laser device, possessing a pulse width on the order of hundreds of femtoseconds and single-energy characteristics. Clearly, given that this X-ray free-electron laser pulse is a single-energy X-ray pulse, there is no need to differentiate between X-rays of different energies during the measurement process. The measurement primarily focuses on the pulse characteristic values ​​of different X-rays, such as pulse charge integral, pulse height, and pulse shape. Furthermore, in this embodiment, the X-ray detection module 100 is equipped with a photodiode, which generates a current pulse after receiving X-ray free-electron laser irradiation. The photodiode, as an optoelectronic device that can efficiently convert optical signals into electrical signals, has advantages such as ease of use, simple structure, and normal operation at room temperature.

[0050] In one exemplary embodiment of this application, please refer to Figure 2 As shown, the first signal processing module 200 includes a gating switch unit 220 and a signal amplification unit 230. The input terminal of the gating switch unit 220 is connected to the output terminal of the X-ray detection module 100, and the output terminal is connected to the input terminal of the signal amplification unit 230. It is used to automatically select the corresponding signal path based on the signal strength of the current pulse signal output by the X-ray detection module 100. The input terminal of the signal amplification unit 230 is connected to the output terminal of the gating switch unit 220, and the output terminal is connected to the input terminal of the second signal processing module 300. It is used to amplify the current pulse signal output by the X-ray detection module 100 and perform current-to-voltage conversion to generate the voltage pulse analog signal.

[0051] In one exemplary embodiment of this application, please refer to Figure 2 As shown, the selection switch unit 220 includes a single-pole multi-throw switch. The input terminal of the single-pole multi-throw switch is connected to the output terminal of the X-ray detection module 100, and each output terminal of the single-pole multi-throw switch is connected to each input terminal of the signal amplification unit 230, respectively, for automatically selecting the corresponding signal path according to the signal strength of the current pulse signal output by the X-ray detection module 100.

[0052] In an exemplary embodiment of this application, the signal amplification unit 230 includes multiple amplifiers with different amplification factors. The input terminals of the multiple amplifiers with different amplification factors are respectively connected to the respective output terminals of the gating switch unit 220, and their output terminals are connected to the input terminal of the second signal processing module 300. These amplifiers amplify the current pulse signal output by the X-ray detection module 100 and perform current-to-voltage conversion to generate the voltage pulse analog signal. It should be noted that in this embodiment, the amplifier includes a transimpedance amplifier or a charge-sensitive amplifier; different amplifiers can have their bandwidth and amplification factor customized according to actual needs.

[0053] Specifically, in this embodiment, the first signal processing module 200 is designed and built around a transimpedance amplifier. Its input is connected to the photodiode in the X-ray detection module 100, and its output is connected to the second signal processing module 300. Its main function is to filter and amplify the current pulse signal output by the photodiode, and then convert it into a voltage pulse analog signal. It is worth noting that in this embodiment, a single-pole double-throw switch is used to select amplifiers with amplification factors of G = 100V / A and G = 1000V / A, respectively, and the bandwidth of both amplifiers is greater than 10MHz. Of course, in other embodiments, multiple amplifiers with different amplification factors can be customized according to specific needs to meet different signal processing requirements.

[0054] In one exemplary embodiment of this application, please refer to Figure 2 As shown, the first signal processing module 200 further includes a filtering unit 210. The input terminal of the filtering unit 210 is connected to the output terminal of the X-ray detection module 100, and the output terminal is connected to the input terminal of the gating switch unit 220. It is used to filter the current pulse signal output by the X-ray detection module 100 to remove noise interference.

[0055] In one exemplary embodiment of this application, please refer to Figure 3As shown, the second signal processing module 300 includes an analog-to-digital converter (ADC) unit 310 and a digital signal processing unit 320. The input terminal of the ADC unit 310 is connected to the output terminal of the first signal processing module 200, and its output terminal is connected to the input terminal of the digital signal processing unit 320. It is used to convert the analog voltage pulse signal into a digital voltage pulse signal. The output terminal of the digital signal processing unit 320 is connected to the input terminal of the acquisition and display module 400. It is used to extract pulse features from the digital voltage pulse signal to obtain pulse feature values, which include pulse charge integral, pulse height, and pulse shape. It should be noted that the pulse charge integral characterizes the intensity of the X-ray free-electron laser pulse, reflecting the total charge carried by the pulse. The pulse height reflects the peak height of the pulse signal at a specific moment, visually representing the instantaneous intensity of the pulse. The pulse shape describes the morphological characteristics of the pulse signal over time; analysis of the pulse shape provides a deeper understanding of the generation and propagation characteristics of X-ray free-electron laser pulses.

[0056] Specifically, the pulse shape is closely related to the time characteristic parameter. After the voltage pulse analog signal is processed by the timing filter, it is converted into a bipolar signal. The zero-crossing point of this bipolar signal corresponds to a precise timestamp, thereby allowing the extraction of the pulse signal's arrival time characteristic parameter. This parameter indirectly reflects the initial characteristics of the pulse shape in the time dimension. The pulse height corresponds to the signal amplitude characteristic parameter. When the voltage pulse analog signal is input to the digital trapezoidal filter in the digital signal processing unit 320, a trapezoidal waveform is output. The height of the top of this trapezoidal waveform corresponds to the input voltage pulse signal amplitude characteristic parameter, which directly reflects the relevant information of the pulse height. The pulse charge integral is matched with the charge quantity characteristic parameter, which is obtained by integrating the sample values ​​obtained after analog-to-digital conversion within the programmable gate width range. The programmable gate width can be set according to actual needs, and the start time of the gate width is automatically determined by the trigger time. The resulting charge quantity characteristic parameter effectively characterizes the pulse charge integral.

[0057] In one exemplary embodiment of this application, please refer to Figure 1 As shown, the connecting cables between the X-ray detection module 100 and the first signal processing module 200, and between the first signal processing module 200 and the second signal processing module 300, are coaxial cables to shield against noise interference. It should be noted that the coaxial cable consists of an inner conductor, an insulating medium, a shielding layer, and an outer sheath.

[0058] In an exemplary embodiment of this application, the second signal processing module adopts a desktop terminal-based structural design, enabling it to flexibly switch between multiple long-distance measurement points according to actual measurement needs.

[0059] In an exemplary embodiment of this application, the second signal processing module performs analog-to-digital conversion and pulse feature extraction on the voltage pulse analog signal using a field-programmable gate array (FPGA) to achieve real-time tracking and measurement of the characteristics of high-repetition-rate X-ray free-electron laser pulses. It should be noted that high-repetition-rate X-ray free-electron laser pulses have extremely high repetition rates (e.g., MHz to GHz), making it difficult for traditional serial processors (such as CPUs) to complete signal acquisition, conversion, and feature extraction in such a short time. FPGAs, through their hardware parallel architecture, can process multiple signal channels or tasks simultaneously, significantly improving processing speed and meeting real-time requirements.

[0060] In an exemplary embodiment of this application, the acquisition and display module 400 has flexible display functions, capable of directly displaying voltage pulse waveform data or displaying pulse characteristic values, their changing trends, and statistical distributions in graphical form according to actual needs. In this embodiment, the software program of the acquisition and display module 400 is developed using the Python language. The functions of the acquisition and display module 400 include setting various parameters for acquisition and display, such as acquisition channels, bias percentage, trigger threshold, data recording length, and integration gate length. In addition, the module can also acquire and display the raw data of the pulse waveform, or display the pulse charge integral and its changing trend.

[0061] In summary, the high repetition rate X-ray free electron laser pulse measurement system provided by the present invention includes: an X-ray detection module 100, a first signal processing module 200, a second signal processing module 300, and an acquisition and display module 400. The X-ray detection module 100 receives X-ray free electron laser pulse irradiation and converts the optical signal into a current pulse signal via a photodiode. The input terminal of the first signal processing module 200 is connected to the output terminal of the X-ray detection module 100, and is used to filter and amplify the current pulse signal and perform current-to-voltage conversion to generate a voltage pulse analog signal. The input terminal of the second signal processing module 300 is connected to the output terminal of the first signal processing module 200, and is used to perform analog-to-digital conversion and pulse feature extraction on the voltage pulse analog signal to generate a voltage pulse digital signal and its corresponding pulse feature value. The input terminal of the acquisition and display module 400 is connected to the output terminal of the second signal processing module 300, and is used to acquire and display the voltage pulse digital signal and its corresponding pulse feature value. This system is capable of tracking and measuring high-repetition-rate X-ray free-electron laser pulses, enabling precise measurement of signal intensity over a large dynamic range. It can also acquire and display the original waveform, pulse characteristic values, and trends of the pulse signal according to actual needs, providing solid technical support for beamline diagnostics on high-repetition-rate X-ray free-electron laser devices and incident beam positioning tasks at experimental stations.

[0062] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A high-repetition-rate X-ray free-electron laser pulse measurement system, characterized in that, include: X-ray detection module, first signal processing module, second signal processing module and acquisition and display module; The X-ray detection module is used to receive X-ray free electron laser pulses and convert the optical signal into a current pulse signal through a photodiode. The input terminal of the first signal processing module is connected to the output terminal of the X-ray detection module, and is used to filter and amplify the current pulse signal and complete the current-to-voltage conversion to generate a voltage pulse analog signal. The input terminal of the second signal processing module is connected to the output terminal of the first signal processing module, and is used to perform analog-to-digital conversion and pulse feature extraction on the voltage pulse analog signal to generate a voltage pulse digital signal and its corresponding pulse feature value; The input terminal of the acquisition and display module is connected to the output terminal of the second signal processing module, and is used to acquire and display the voltage pulse digital signal and its corresponding pulse characteristic value.

2. The high repetition rate X-ray free electron laser pulse measurement system according to claim 1, characterized in that, The X-ray free-electron laser pulses are generated by a free-electron laser device and have pulse widths in the hundreds of femtosecond range and single-energy characteristics.

3. The high repetition rate X-ray free electron laser pulse measurement system according to claim 1, characterized in that, The first signal processing module includes a gating switch unit and a signal amplification unit; The input terminal of the gating switch unit is connected to the output terminal of the X-ray detection module, and the output terminal is connected to the input terminal of the signal amplification unit. It is used to automatically select the corresponding signal path according to the signal strength of the current pulse signal output by the X-ray detection module. The input terminal of the signal amplification unit is connected to the output terminal of the gating switch unit, and the output terminal is connected to the input terminal of the second signal processing module. It is used to amplify the current pulse signal output by the X-ray detection module and complete the current-voltage conversion to generate the voltage pulse analog signal.

4. The high repetition rate X-ray free electron laser pulse measurement system according to claim 3, characterized in that, The gating switch unit includes a single-pole multi-throw switch; The input terminal of the single-pole multi-throw switch is connected to the output terminal of the X-ray detection module, and each output terminal of the single-pole multi-throw switch is connected to each input terminal of the signal amplification unit, respectively, for automatically selecting the corresponding signal path according to the signal strength of the current pulse signal output by the X-ray detection module.

5. The high repetition rate X-ray free electron laser pulse measurement system according to claim 3, characterized in that, The signal amplification unit includes multiple amplifiers with different amplification factors; The input terminals of the plurality of amplifiers with different multiples are respectively connected to the corresponding output terminals of the gating switch unit, and the output terminals are connected to the input terminal of the second signal processing module. They are used to amplify the current pulse signal output by the X-ray detection module and complete the current-to-voltage conversion to generate the voltage pulse analog signal.

6. The high repetition rate X-ray free electron laser pulse measurement system according to claim 3, characterized in that, The first signal processing module further includes a filtering unit; The input terminal of the filtering unit is connected to the output terminal of the X-ray detection module, and the output terminal is connected to the input terminal of the gating switch unit. It is used to filter the current pulse signal output by the X-ray detection module to remove noise interference.

7. The high repetition rate X-ray free electron laser pulse measurement system according to claim 1, characterized in that, The second signal processing module includes an analog-to-digital conversion unit and a digital signal processing unit; The input terminal of the analog-to-digital converter is connected to the output terminal of the first signal processing module, and the output terminal is connected to the input terminal of the digital signal processing unit, for converting the voltage pulse analog signal into a voltage pulse digital signal; The output of the digital signal processing unit is connected to the input of the acquisition and display module, and is used to extract pulse features from the voltage pulse digital signal to obtain pulse feature values ​​of the voltage pulse digital signal. The pulse feature values ​​include pulse charge integral, pulse height, and pulse shape.

8. The high repetition rate X-ray free electron laser pulse measurement system according to claim 1, characterized in that, The connecting cables between the X-ray detection module and the first signal processing module, and between the first signal processing module and the second signal processing module, are coaxial cables to shield against noise interference.

9. The high repetition rate X-ray free electron laser pulse measurement system according to claim 1, characterized in that, The second signal processing module adopts a desktop terminal-based architecture, enabling it to flexibly switch between multiple long-distance measurement points according to actual measurement needs.

10. The high repetition rate X-ray free electron laser pulse measurement system according to claim 1, characterized in that, The second signal processing module performs analog-to-digital conversion and pulse feature extraction on the voltage pulse analog signal through a field-programmable gate array to achieve real-time tracking and measurement of the characteristics of high-repetition-rate X-ray free-electron laser pulses.

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