Wire scanning signal acquisition system and method capable of distinguishing macro-pulse structure of beam current

Abstract

The application discloses a filament scanning signal collection system and method capable of distinguishing macro-pulse structure of a beam current, and the system comprises a Faraday cylinder, a data collection card, a filament scanning device and a PC machine; the Faraday cylinder is used for transmitting a current intensity signal to the data collection card; the data collection card judges the time structure of a preceding macro-pulse beam current and controls the sampling time of the filament scanning device; the filament scanning device collects data when receiving the instruction of the data collection card; the data collection card transmits effective data to a filtering unit; the method comprises the following steps: the Faraday cylinder acquires the current intensity signal of the current macro-pulse beam current; the data collection card performs a pulse edge detection algorithm according to the current intensity; the filament scanning device collects data at the rising edge of the pulse; and the data collection card transmits effective data to a low-pass filtering unit; the application makes the filament scanning collection interval concentrate on the beam current part of the pulse beam, and a digital filtering method is provided for the problems of weak filament scanning measurement signal and great environmental noise influence in proton therapy.

Description

Technical Field

[0001] This invention belongs to the field of cyclotron technology, specifically relating to a wire scanning signal acquisition system and method that can distinguish beam macropulse structures. Background Technology

[0002] Beam diagnostic equipment is an essential component of any type of accelerator. Measuring various beam parameters using beam diagnostic systems provides crucial information for accelerator research and performance improvement. Beam profile parameters are closely related to accelerator performance and safety; beam path alignment and beam spot shape adjustments both require the information provided by these parameters.

[0003] wire scanning detectors, such as Figure 6 As shown, this is a device that uses one or more wires to scan a beam to detect its transverse cross-sectional distribution, and calculates the beam emittance information based on the measurement results from multiple wire scanning devices. Because wire scanning devices cause less beam obstruction and have less impact on beam quality, they can better ensure that the beam quality meets medical requirements for medical cyclotrons.

[0004] The challenges of wire scanning signal acquisition are: 1) During the accelerator commissioning phase, the wire scanner deals with a macropulse beam, not a conventional pulse beam. Macropulse beams have a longer period and a relatively smaller duty cycle compared to conventional pulse beams, while conventional pulse beams have shorter periods. For the latter, with its high pulse frequency, the beam signal can be sampled directly without considering the beam time structure. However, the macropulse beam has a relatively long non-current region. If the beam signal is sampled directly without considering the beam time structure, the sampling results will be concentrated in areas where the pulse beam has current and in areas where the pulse beam has no current, ultimately leading to distorted measurement results. 2) The method of measuring the beam cross-section using wire scanning differs from that of conventional ionization chambers. Conventional ionization chambers are relatively stationary: they consist of several ionization strips, each strip corresponding to a signal output, and the beam cross-section is obtained through the electrical signals of the strips. In contrast, the wire scanning device is a moving mechanism that scans data while moving along a trajectory. During operation, mechanical vibrations, high-frequency arcing, or other special events can lead to inaccurate wire scanning measurement data, meaning the number of scan points within the specified time may fall short of the theoretically calculated number. 3) Wire scanning measurement has low efficiency and weak proton therapy beam intensity. Compared to ionization chamber devices, due to the low efficiency of wire scanning measurement, the wire scanning diagnostic signal is often very weak and easily drowned out by noise when encountering multiple environmental interference sources. 4) A large amount of sampling data increases the processing time and affects the beam parameter calculation results. Summary of the Invention

[0005] The present application aims at the deficiencies of the prior art, and provides a wire scanning signal acquisition system and method capable of distinguishing macro-pulse structure of a beam current, a first object of which is to solve the problem that wire scanning sampling can distinguish time structure of a beam current, a second object of which is to solve the problem that wire scanning measurement signals are extremely susceptible to noise interference, and a third object of which is to solve the problem that a large amount of sampling data increases processing time of a program and affects calculation results of beam current parameters.

[0006] The present application adopts the following technical solutions to solve the technical problems:

[0007] The wire scanning signal acquisition system capable of distinguishing macro-pulse structure of a beam current comprises a Faraday cylinder, a data acquisition card, a wire scanning device, and a PC, wherein the Faraday cylinder is used for diagnosing a current macro-pulse beam current intensity signal and sending the current macro-pulse beam current intensity signal to the data acquisition card; the data acquisition card is used for judging time structure of a previous macro-pulse beam current according to the current macro-pulse beam current intensity signal and controlling a wire scanning device to start sampling or stop sampling according to the time structure; the wire scanning device is used for starting to acquire signals when receiving a pulse rising edge signal of the data acquisition card, and feeding back acquired information to the data acquisition card; the wire scanning device is used for stopping to acquire signals when receiving a pulse falling edge signal of the data acquisition card; the data acquisition card is used for judging validity of wire scanning data, performing low-pass filtering and smoothing filtering on valid wire scanning data, and sending the valid wire scanning data after the low-pass filtering and the smoothing filtering to the PC; and the PC is used for displaying wire scanning diagnosis results.

[0008] Further, the data acquisition card comprises a data validity judging unit, a low-pass filtering unit, a smoothing filtering unit, and a time structure distinguishing unit; the data validity judging unit is used for judging validity of wire scanning data and sending valid wire scanning data to the low-pass filtering unit; the low-pass filtering unit and the smoothing filtering unit are used for performing high-frequency noise filtering and random noise filtering on sampling signals of the wire scanning device, and sending wire scanning diagnosis results after the filtering to the PC; and the time structure distinguishing unit is used for distinguishing time structure according to a current macro-pulse beam current intensity signal provided by the Faraday cylinder and controlling sampling time of the wire scanning device according to a distinguishing result.

[0009] Further, the time structure distinguishing unit comprises an edge detection algorithm module, which comprises a sampling frequency determining sub-module, a received pulse beam current signal intensity sub-module, a background signal intensity measuring sub-module, an edge detection sub-module, a sampling point number n p between rising edges and falling edges recording sub-module, a sampling point number n T between adjacent pulse rising edges or falling edges recording sub-module, a pulse period calculating sub-module, and a duty cycle calculating sub-module; the sampling frequency determining sub-module and the background signal intensity measuring sub-module are used for determining a signal sampling frequency f sf, and measuring the background signal intensity v0; the received pulse beam signal intensity submodule is used for receiving the pulse beam current intensity v beam of the Faraday cup beam ; the edge detection submodule is used for judging the rising edge of the pulse signal and the falling edge of the pulse signal according to the pulse beam current intensity v p and the background signal intensity v0 T ; the duty cycle calculation submodule calculates the duty cycle D = n p / n T according to the number of sampling points n p between the rising edge and the falling edge and the number of sampling points n T between adjacent rising edges or falling edges.

[0010] Further, the data validity judging unit comprises a recording wire scanning sampling point number module, a setting wire scanning sampling frequency module, a calculating wire scanning theoretical sampling point number module, and a difference calculating module; the recording wire scanning sampling point number module and the calculating wire scanning theoretical sampling point number module provide the wire scanning actual sampling point number and the wire scanning theoretical sampling point number for the difference calculating module; the calculating wire scanning theoretical sampling point number module calculates the wire scanning theoretical sampling point number according to the period T of the resolution time structure module, the duty cycle D, and the wire scanning sampling frequency.

[0011] A wire scanning signal collecting method capable of distinguishing the macro pulse structure of the beam current, comprising the following steps:

[0012] Step one, the Faraday cup acquires the current macro pulse beam current intensity signal and sends the beam current intensity signal to the resolution time structure unit of the data acquisition card;

[0013] Step two, the data acquisition card performs a pulse edge detection algorithm: the resolution time structure unit distinguishes the beam current time structure through the pulse edge detection algorithm, controls the wire scanning device to start sampling when the rising edge of the pulse signal is detected, and controls the wire scanning device to stop sampling when the falling edge of the pulse signal is detected;

[0014] Step three, the wire scanning device samples: starts sampling when the rising edge signal of the pulse signal is received in each period, stops sampling when the falling edge signal of the pulse signal is received in each period, and sends the pulse sampling data of each period to the data validity judging unit of the data acquisition card;

[0015] Step four, the data acquisition card judges the validity of the data and sends the valid data to the low-pass filter unit;

[0016] Step five, the low-pass filter and smoothing filter unit carries out digital filtering processing on the filament scanning sampling signal, wherein the low-pass filter is used for filtering high-frequency noise of the filament scanning sampling signal, the smoothing filter is used for filtering random noise of the filament scanning sampling signal, and the filtered data is compressed in size by a downsampling method, and the compressed data is the final filament scanning sampling signal.

[0017] Further, the pulse edge detection algorithm of step two includes the following processes:

[0018] 1) Before measuring the beam by the Faraday cup, first determine the signal sampling rate of the Faraday cup channel of the data acquisition card and measure the background signal intensity.

[0019] 2) When measuring the beam, measure the pulse beam intensity, when the sampling value is greater than, it is considered that the pulse signal rising edge, when the sampling value is less than, it is considered that the pulse signal falling edge, record the sampling point number between the rising edge and the falling edge, and the sampling point number between the adjacent pulse rising edge or falling edge.

[0020] 3) Calculate the pulse period and pulse duty cycle.

[0021] Further, the data acquisition card judges the validity of the data in step four, and sends the valid data to the low-pass filter unit, and the specific process is as follows:

[0022] 1) The data validity judgment unit records the filament scanning sampling point number.

[0023] 2) Set the sampling rate of the filament scanning signal sampling channel to

[0024] 3) Compare the actual sampling point number with the theoretical sampling point number: specifically, compare the actual sampling point number with the theoretical sampling point number according to the pulse signal period T and the duty cycle D;

[0025] 4) If the actual sampling point number of the filament scanning per cycle is less than one fifth of the theoretical sampling point number, that is,, it is considered that the filament scanning sampling data in this section is invalid, and the invalid filament scanning data is abandoned, not performing subsequent low-pass filtering, and returning to process 1);

[0026] 5) The valid filament scanning data is sent to the low-pass filter and smoothing filter unit of the data acquisition card.

[0027] Further, the filament scanning device of step three removes the head and tail data of the pulse sampling data of each cycle, and retains the middle section data as the pulse sampling data of the cycle.

[0028] Further, the data without the head and tail is kept as the pulse sampling data of the period, that is, 10% of the data at the head and tail of the array is removed, and 80% of the data in the middle section is kept as the effective sampling data of the wire scanning.

[0029] Further, the specific process of step five is as follows:

[0030] 1) Establish the coefficient lookup table of the difference equation of the Butterworth filter;

[0031] 2) Input the wire scanning sampling data into the Butterworth low-pass filter, and the output of the low-pass filter is the sampling data filtered of high-frequency noise;

[0032] 3) After low-pass filtering, perform smoothing filtering, the arithmetic mean of each period pulse data is calculated, and the calculation mean is taken as the wire scanning sampling signal of the pulse period and is sent to the PC for displaying the result; the output of the smoothing filter is the sampling data filtered of random noise.

[0033] Advantages and effects of the present application

[0034] 1) The present application proposes a wire scanning signal collection method capable of distinguishing the time structure of the beam, aiming at the problem that the macro-pulse beam is difficult to distinguish the time structure of the beam, thereby leading to the distortion of the measurement result. The beam is continuously measured by a Faraday cylinder, the edges of the pulse beam are distinguished, the pulse edges are used as a trigger, and the wire scanning collection signal is enabled. The method makes the wire scanning collection interval concentrate on the beam-carrying part of the pulse beam, and avoids the interference of invalid information on the wire scanning measurement result.

[0035] 2) The present application proposes a data validity judgment, aiming at the problem that the sudden event in the wire scanning measurement process leads to the generation of large peak signals and interferes with the measurement. The number of wire scanning sampling points is recorded and compared with the theoretically calculated sampling points, when the number is lower than the lower limit value, it is considered as invalid data, and the sampling data higher than the lower limit value is sent to the filtering unit, thereby solving the problem that large burr signals may be collected in the wire scanning measurement process.

[0036] 3) The present application proposes a digital filtering method, aiming at the problem that the wire scanning measurement signal of the proton therapy is weak and the environmental noise is large. The high-frequency noise in the wire scanning signal is filtered through a Butterworth low-pass filter, and the random noise is filtered and the data scale is compressed through arithmetic mean filtering, and the compressed data is taken as the final wire scanning diagnostic result. The method can improve the signal-to-noise ratio of the wire scanning sampling signal, and the compressed data scale is beneficial to subsequent beam profile parameter calculation. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 It is a functional block diagram of the wire scanning signal collection device of the present application.

[0038] Figure 2 The function block diagram of the resolution time structure unit of the present application;

[0039] Figure 3 The function block diagram of the data validity judging unit of the present application;

[0040] Figure 4 The flow chart of the wire scanning signal collecting method of the present application;

[0041] Figure 5 The schematic diagram of the macro pulse period;

[0042] Figure 6 The schematic diagram of the wire scanning device. DETAILED DESCRIPTION

[0043] The design principle of the present application

[0044] 1. The innovation point: the wire scanning device, the Faraday cylinder, the resolution time structure unit, the data validity judging unit, the low-pass filtering unit and the smoothing filtering unit are organically combined, and the combination produces a new effect, that is, the wire scanning device is used to measure the beam cross section instead of the conventional ionization chamber method in the field of medical cyclotron, and the wire scanning device has higher measurement resolution, smaller beam blocking and smaller influence on beam quality, and can better ensure the beam quality and meet the medical needs.

[0045] 2. The design principle of the organic combination of each part: first, the combination of the Faraday cylinder and the data acquisition card solves the problem of dividing the beam time structure, specifically, the resolution time structure unit of the data acquisition card judges whether it is a rising edge or a falling edge according to the current of the Faraday cylinder, so as to control the start sampling and stop sampling time of the wire scanning, thereby ensuring that the data sampled by the wire scanning is definitely pulsed data, which is the first time to avoid the distortion of the measurement result. Second, the combination of the wire scanning device and the data validity judging unit of the data acquisition card solves the problem of collecting large burr signals by the wire scanning device. Specifically, the data validity judging unit records the number of four scans at any time, then calculates the theoretical wire scanning point number, and then compares the two numbers, when the lower limit value is exceeded, it is considered as invalid data, and the invalid data is abandoned, which is the second time to avoid the distortion of the measurement result. Third, the combination of the data validity judging unit and the low-pass filtering and smoothing filtering (including downsampling) units further ensures the measurement accuracy. The low-pass filtering unit solves the problem of filtering high-frequency noise, and the smoothing filtering unit solves the problem of filtering random noise, at the same time, the smoothing filtering unit further downsamples, which further condenses the sampling data amount and reduces the data operation amount, solving the problem of affecting the accuracy of the calculation result due to too large data amount. This is the third time to avoid the distortion of the measurement result.

[0046] In summary, the present application overcomes the factors that cause the measurement result distortion when the wire scanning device is used to measure the beam cross section from three aspects. The three factors interact with each other and depend on each other. Ignoring any one of the factors will affect the accuracy of the wire scanning measurement of the beam cross section.

[0047] Based on the above inventive principle, the present application designs a wire scanning signal acquisition system capable of distinguishing the macro-pulse structure of the beam, as shown in Figures 1-3 The system comprises a Faraday cylinder, a data acquisition card, a wire scanning device, and a PC. The Faraday cylinder is used to diagnose the current of the macro-pulse beam and send the current signal to the data acquisition card. The data acquisition card judges the time structure of the macro-pulse beam according to the current signal and controls the start time or stop time of the sampling of the wire scanning device according to the time structure. The wire scanning device starts to collect signals when receiving the rising edge signal of the data acquisition card and feeds back the collected information to the data acquisition card. The wire scanning device stops collecting signals when receiving the falling edge signal of the data acquisition card. The data acquisition card judges the validity of the wire scanning data, performs low-pass filtering and smoothing filtering on the valid wire scanning data, and sends the smoothed data to the PC. The PC is used to display the wire scanning diagnosis result.

[0048] Supplementary Note 1

[0049] The Faraday cylinder is a device for collecting electric charges. A current meter is arranged between the Faraday cylinder and the ground. When a pulse beam of one period comes, the Faraday cylinder receives a group of electric charges at the same time. The electric charges flow through the current meter to obtain the beam current data. When there is no beam, the current meter measures 0. When the next pulse period comes, the Faraday cylinder receives another group of electric charges, and the reading of the current meter starts to rise from 0, and the process is repeated.

[0050] The data acquisition card comprises a data validity judgment unit, a low-pass filtering unit, a smoothing filtering unit, and a time structure distinguishing unit. The data validity judgment unit judges the validity of the wire scanning data and sends the valid wire scanning data to the low-pass filtering unit. The low-pass filtering and smoothing filtering unit performs high-frequency noise filtering and random noise filtering on the sampling signal of the wire scanning device and sends the filtered wire scanning diagnosis result to the PC. The time structure distinguishing unit distinguishes the time structure according to the current signal provided by the Faraday cylinder and controls the sampling time of the wire scanning device according to the distinguishing result.

[0051] The time structure distinguishing unit comprises an edge detection algorithm module, as shown in Figure 5As shown, the edge detection algorithm module includes: a sampling frequency determination submodule, a pulse beam signal strength receiving submodule, a background signal strength measurement submodule, an edge detection submodule, and a recording submodule for the number of sampling points n between the rising and falling edges. p Submodule, number of sampling points n between adjacent rising or falling edges of pulses T The submodules include a pulse period calculation submodule and a duty cycle calculation submodule; the sampling frequency determination submodule and the background signal strength measurement submodule are used to determine the signal sampling frequency f before the Faraday tube measures the beam. sf And to measure the background signal strength v0; the receiving pulse beam signal strength submodule is used to receive the pulse beam current strength v0 of the Faraday tube. beam The edge detection submodule is used to detect the pulse beam current intensity v. beam The rising edge and falling edge of the pulse signal are determined by the background signal strength v0; the duty cycle calculation submodule is based on the number of sampling points n between the rising and falling edges. p The number of sampling points n between the rising or falling edges of adjacent pulses T Calculate the duty cycle D = n p / n T .

[0052] The data validity judgment unit includes a recording wire scanning sampling point count module, a wire scanning sampling frequency setting module, a wire scanning theoretical sampling point count calculation module, and a difference calculation module. The recording wire scanning sampling point count module and the wire scanning theoretical sampling point count calculation module provide the difference calculation module with the actual number of wire scanning sampling points and the theoretical number of sampling points. The wire scanning theoretical sampling point count calculation module calculates the wire scanning theoretical sampling point count based on the period T and duty cycle D of the resolution time structure module and the wire scanning sampling frequency.

[0053] A method for acquiring wire scanning signals that can resolve beam macropulse structures, such as Figure 4 As shown, its characteristics include the following steps:

[0054] Step 1: The Faraday tube acquires the current intensity signal of the current macropulse beam and sends the current intensity signal to the resolution time structure unit of the data acquisition card;

[0055] Step 2: The data acquisition card performs a pulse edge detection algorithm: The time structure resolution unit resolves the beam time structure through a pulse edge detection algorithm. When the rising edge of the pulse signal is detected, the control wire scanning device starts sampling, and when the falling edge of the pulse signal is detected, the control wire scanning device stops sampling.

[0056] Step three, the wire scanning device sampling: start sampling when receiving the rising edge signal of the pulse signal in each cycle, stop sampling when receiving the falling edge signal of the pulse signal in each cycle, and send the pulse sampling data in each cycle to the data validity judgment unit of the data acquisition card;

[0057] Step four, the data acquisition card judges the validity of the data and sends the valid data to the low-pass filtering unit;

[0058] Step five, the low-pass filtering and smoothing filtering unit performs digital filtering processing on the wire scanning sampling signal, wherein the low-pass filtering is used for filtering the high-frequency noise of the wire scanning sampling signal, the smoothing filtering is used for filtering the random noise of the wire scanning sampling signal, and the filtered data is compressed in size by a downsampling method, and the compressed data is the final wire scanning sampling signal.

[0059] The pulse edge detection algorithm of step two includes the following processes:

[0060] 1) Before measuring the beam by the Faraday cup, first determine the signal sampling rate of the Faraday cup channel of the data acquisition card and measure the background signal intensity;

[0061] 2) When measuring the beam, measure the pulse beam intensity, when the sampling value is greater than, it is considered as the rising edge of the pulse signal, when the sampling value is less than, it is considered as the falling edge of the pulse signal, record the sampling point number between the rising edge and the falling edge, and the sampling point number between adjacent pulse rising edges or falling edges.

[0062] 3) Calculate the pulse period and pulse duty cycle.

[0063] The data acquisition card judges the validity of the data in step four and sends the valid data to the low-pass filtering unit, and the specific process is as follows:

[0064] 1) The data validity judgment unit records the wire scanning sampling point number;

[0065] 2) Set the sampling rate of the wire scanning signal sampling channel to

[0066] 3) Compare the actual sampling point number with the theoretical sampling point number: specifically, compare the actual sampling point number with the theoretical sampling point number according to the pulse signal period T and the duty cycle D;

[0067] 4) If the actual wire scanning sampling point number per cycle is less than one fifth of the theoretical sampling point number, that is,, it is considered that the wire scanning sampling data in this section is invalid, and the invalid wire scanning data is abandoned and does not perform subsequent low-pass filtering, and returns to process 1);

[0068] 5) The valid wire scanning data is sent to the low-pass filtering and smoothing filtering unit of the data acquisition card.

[0069] The wire scanning device of step three removes the head and tail data of the data of each cycle pulse sampling and retains the middle section data as the cycle pulse sampling data.

[0070] The wire scanning device of step three removes the head and tail data of the data of each cycle pulse sampling and retains the middle section data as the cycle pulse sampling data, that is, removing 10% of the data of the head and tail of the array, and retaining 80% of the data of the middle section as the effective sampling data of the wire scanning.

[0071] The specific process of step five is as follows:

[0072] 1) Establishing the coefficient lookup table of the difference equation of the Butterworth filter;

[0073] 2) Inputting the wire scanning sampling data into the Butterworth low-pass filter, and the output result of the low-pass filter is the sampling data filtered from the high-frequency noise;

[0074] 3) After the low-pass filtering, performing the smoothing filtering, the smoothing filtering calculates the arithmetic mean of each cycle pulse data, and the calculation mean is taken as the wire scanning sampling signal of the pulse cycle and is sent to the PC for displaying the result; the output result of the smoothing filter is the sampling data filtered from the random noise.

[0075] The above content is only an example and description of the concept of the present application, and those skilled in the art can make various modifications or supplements to the described specific embodiments or adopt similar ways to replace, as long as the modifications or supplements do not deviate from the concept of the present application or exceed the range defined by the present application, and should belong to the protection scope of the present application.

Claims

1. A wire scanning signal acquisition system capable of resolving beam macropulse structures, characterized in that: The system includes a Faraday lamp, a data acquisition card, a wire scanning device, and a PC. The Faraday lamp is used to diagnose the current intensity signal of the current macropulse beam and send the current intensity signal to the data acquisition card. The data acquisition card determines the time structure of the current macropulse beam based on the current intensity signal and controls the start or stop sampling time of the wire scanning device according to the time structure. The wire scanning device starts acquiring signals when it receives the rising edge of the pulse signal from the data acquisition card and feeds back the acquired information to the data acquisition card. It stops acquiring signals when it receives the falling edge of the pulse from the data acquisition card. The data acquisition card determines the validity of the wire scanning data, performs low-pass filtering and smoothing filtering on the valid wire scanning data, and sends the smoothed data to the PC. The PC is used to display the wire scanning diagnostic results. The data acquisition card includes a data validity judgment unit, a low-pass filter unit, a smoothing filter unit, and a time structure resolution unit. The data validity judgment unit judges the validity of the wire scanning data and sends the valid wire scanning data to the low-pass filter unit. The low-pass filter and smoothing filter units perform high-frequency noise filtering and random noise filtering on the sampling signal of the wire scanning device, and send the filtered wire scanning diagnostic results to the PC. The time structure resolution unit performs time structure resolution based on the current intensity signal provided by the Faraday cylinder, and controls the sampling time of the wire scanning device based on the resolution result. The time resolution structure unit includes an edge detection algorithm module, which comprises: a sampling frequency determination submodule, a pulse beam signal strength receiving submodule, a background signal strength measurement submodule, an edge detection submodule, and a recording submodule for the number n sampling points between the rising and falling edges. p Submodule, number of sampling points n between adjacent rising or falling edges of pulses T The submodules include a pulse period calculation submodule and a duty cycle calculation submodule; the sampling frequency determination submodule and the background signal strength measurement submodule are used to determine the signal sampling frequency f before the Faraday tube measures the beam. sf And to measure the background signal strength v0; the receiving pulse beam signal strength submodule is used to receive the pulse beam current strength v0 of the Faraday tube. beam ; The edge detection submodule is used to detect the pulsed beam current intensity v. beam The rising edge and falling edge of the pulse signal are determined by the background signal strength v0; the duty cycle calculation submodule is based on the number of sampling points n between the rising and falling edges. p The number of sampling points n between the rising or falling edges of adjacent pulses T Calculate the duty cycle D = n p / n T .

2. The wire scanning signal acquisition system for a resolvable beam macropulse structure according to claim 1, characterized in that: The data validity judgment unit includes a recording wire scanning sampling point count module, a wire scanning sampling frequency setting module, a wire scanning theoretical sampling point count calculation module, and a difference calculation module. The recording wire scanning sampling point count module and the wire scanning theoretical sampling point count calculation module provide the difference calculation module with the actual number of wire scanning sampling points and the theoretical number of sampling points. The wire scanning theoretical sampling point count calculation module calculates the wire scanning theoretical sampling point count based on the period T and duty cycle D of the resolution time structure module and the wire scanning sampling frequency.

3. A method for acquiring wire scanning signals of a resolvable beam macropulse structure based on a wire scanning signal acquisition system of a resolvable beam macropulse structure according to any one of claims 1-2, characterized in that: Includes the following steps: Step 1: The Faraday tube acquires the current intensity signal of the current macropulse beam and sends the current intensity signal to the resolution time structure unit of the data acquisition card; Step 2: The data acquisition card performs a pulse edge detection algorithm: The time structure resolution unit resolves the beam time structure through a pulse edge detection algorithm. When the rising edge of the pulse signal is detected, the control wire scanning device starts sampling, and when the falling edge of the pulse signal is detected, the control wire scanning device stops sampling. Step 3: Sampling by the wire scanning device: Sampling begins when the rising edge of the pulse signal is received in each cycle and stops when the falling edge of the pulse signal is received in each cycle. The pulse sampling data of each cycle is then sent to the data validity judgment unit of the data acquisition card. Step 4: The data acquisition card determines the validity of the data and sends the valid data to the low-pass filter unit; Step 5: The low-pass filter and smoothing filter units perform digital filtering processing on the wire scanning sampling signal. The low-pass filter is used to filter the high-frequency noise of the wire scanning sampling signal, and the smoothing filter is used to filter the random noise of the wire scanning sampling signal. The filtered data is then compressed by downsampling, and the compressed data is the final wire scanning sampling signal.

4. The wire scanning signal acquisition method for a resolvable beam macropulse structure according to claim 3, characterized in that: The pulse edge detection algorithm in step two includes the following process: 1) Before measuring the beam current using the Faraday tube, first determine the signal sampling rate f of the Faraday tube channel on the data acquisition card. sf And measure the background signal strength v0; 2) When measuring the beam current, the measured pulse beam current intensity is v. beam When the sampled value is greater than (v beam When +v0) / 2, it is considered a rising edge of a pulse signal. When the sampled value is less than (v beam When +v0) / 2, it is considered to be the falling edge of the pulse signal, and the number of sampling points n between the rising and falling edges is recorded. p And the number of sampling points n between adjacent rising or falling edges of pulses. T ; 3) The pulse period T = f is calculated. sf / n T Pulse duty cycle D = n p / n T .

5. The wire scanning signal acquisition method for a resolvable beam macropulse structure according to claim 3, characterized in that: The data acquisition card in step four determines the validity of the data and sends the valid data to the low-pass filtering unit. The specific process is as follows: 1) Data validity judgment unit recording wire scanning sampling points n sw ; 2) Set the sampling rate of the wire scanning signal sampling channel to f sw ; 3) Compare the theoretical number of sampling points with the actual number of sampling points: Specifically, based on the pulse signal period T and duty cycle D, compare the actual number of sampling points n. sw And the theoretical number of sampling points D·f sw ·T; 4) If the actual number of sampling points n per cycle of wire scanning sw Less than one-fifth of the theoretical number of sampling points, i.e., n sw <0.2·D·f sw If T is found, the wire scan sampling data is considered invalid, and the invalid wire scan data is discarded without further low-pass filtering, and the process returns to step 1). 5) Valid wire scan data is sent to the low-pass filter and smoothing filter unit of the data acquisition card.

6. The wire scanning signal acquisition method for a resolvable beam macropulse structure according to claim 3, characterized in that: In step three, the data sampled by the wire scanning device in each cycle pulse is divided into the head and tail sections, and the data in the middle section is retained as the pulse sampling data for that cycle.

7. The wire scanning signal acquisition method for a resolvable beam macropulse structure according to claim 6, characterized in that: The process of removing the data at the beginning and end and retaining the data in the middle section as the pulse sampling data for that period is as follows: remove 10% of the data at the beginning and end of the array and retain 80% of the data in the middle section as the effective sampling data for wire scanning.

8. The method for acquiring wire scanning signals of a resolvable beam macropulse structure according to claim 3, characterized in that: The specific process of step five is as follows: 1) Establish a lookup table for the coefficients of the difference equation of the Butterworth filter; 2) Input the wire scan sampling data into the Butterworth low-pass filter. The output of the low-pass filter is the sampling data after filtering out high-frequency noise. 3) After low-pass filtering, smoothing filtering is performed. The smoothing filter calculates the arithmetic mean of the pulse data for each cycle. This calculated mean is used as the sampling signal for the pulse cycle wire scan and sent to the PC to display the result. The output of the smoothing filter is the sampling data after filtering out random noise.

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