Multi-channel electronics system and monitoring method for beam position and profile monitoring

Abstract

The invention provides a multi-channel electronics system and a monitoring method for beam position and profile monitoring, and relates to the technical field of beam diagnosis. In the system, each channel in an analog signal acquisition front end is used for integrating a current input signal sent by a striping ionization chamber; obtaining a target voltage pulse signal and a target optical signal corresponding to the channel; the digital signal processing rear end is used for determining an average input current corresponding to each channel based on a signal number corresponding to a target voltage pulse signal or a target optical signal output by each channel, a constant charge quantity discharged by each channel in a charge and discharge period and an acquisition time period; based on average input current corresponding to all channels in the analog signal acquisition front end, determining a beam position and a profile monitoring result in an acquisition time period; and the charge quantity of an integrating capacitor in the analog signal acquisition front end is dynamically conserved in a charging and discharging period. According to the invention, the measurement precision is improved under the condition that the input dynamic range is large.

Description

Technical Field

[0001] The present invention relates to the technical field of beam diagnosis, and in particular, to a multi-channel electronics system and a monitoring method for beam position and profile monitoring. Background Art

[0002] In the construction of accelerator engineering projects, the beam diagnosis system plays an indispensable role. Among them, beam position and profile monitoring are key monitoring indicators during the operation of the accelerator. At present, many domestic and foreign research institutions rely on deploying a large number of strip ionization chambers to achieve this monitoring purpose. When the accelerator is operating, the strip ionization chamber generates extremely small current signals under the action of the beam. The number of current signals directly depends on the number of channels of the strip ionization chamber, and the more channels the strip ionization chamber has, the finer the resolution of the measured beam position and profile.

[0003] However, under the same area, the increase in the number of channels will cause the current signals generated by each channel in the strip ionization chamber due to the action of the beam to be even weaker. In related technologies, the current-voltage conversion method is generally used. To collect extremely weak current signals, the amplification gain must be increased at the expense of the passband bandwidth. At the same time, the strip ionization chamber has a large number of channels, and different types of beams, beam intensities, and energies will result in an extremely wide dynamic range of current signals, often exceeding 100 dB. Therefore, how to provide a multi-channel electronics system with a large input dynamic range and capable of measuring the beam position and profile with high precision is an urgent problem to be solved at present. Summary of the Invention

[0004] The present invention provides a multi-channel electronics system and a monitoring method for beam position and profile monitoring, so as to solve the defects of low measurement accuracy and inability to meet the large input dynamic range in the prior art.

[0005] The present invention provides a multi-channel electronics system for beam position and profile monitoring, including: an analog signal acquisition front end and a digital signal processing back end, wherein: The analog signal acquisition front end includes a plurality of channels for acquiring current input signals. Each channel is used to integrate the current input signal sent by the strip ionization chamber to obtain a target voltage pulse signal and a target optical signal corresponding to the current input signal in the channel; The digital signal processing backend is used to determine the average input current corresponding to each channel based on the number of signal quantities corresponding to the target voltage pulse signals or the target optical signals output by each channel, the constant charge amount discharged by each channel during the charge and discharge cycle, and the acquisition period; determine the beam position and profile monitoring results during the acquisition period based on the average input current corresponding to each channel in the analog signal acquisition front end; the integral capacitors in the analog signal acquisition front end conserve the charge amount dynamically during the charge and discharge cycle.

[0006] According to the multi-channel electronics system for beam position and profile monitoring provided by the present invention, each channel includes a current integration unit, a comparator unit, a pulse sequence generator, and a controllable switch unit, wherein: The first input end of the current integration unit is connected to the strip ionization chamber and the controllable switch unit, the second input end of the current integration unit is grounded, and the output end of the current integration unit is connected to the first input end of the comparator unit. The current integration unit is used to receive the current input signal sent by the strip ionization chamber and determine the current integration voltage signal corresponding to the current input signal in the corresponding channel. The output end of the comparator unit is connected to the pulse sequence generator. The comparator unit is used to compare a preset voltage threshold with the current integration voltage signal to obtain a comparison signal. The pulse sequence generator is also connected to the controllable switch unit and is used to determine an initial voltage pulse signal based on the comparison signal. The pulse width of the initial voltage pulse signal is fixed, and the initial voltage pulse signal is used to control the on-off state of the controllable switch unit. The on-off state of the controllable switch unit is used to control the charge amount change state of the integration capacitor in the current integration unit.

[0007] According to the multi-channel electronics system for beam position and profile monitoring provided by the present invention, the analog signal acquisition front end further includes a constant current source unit. The constant current source unit is connected to the controllable switch unit. When the controllable switch unit is in the closed state, the constant current source unit is connected to the first input end of the current integration unit, and the constant current source unit controls the integration capacitor to be in the discharge state.

[0008] According to the multi-channel electronics system for beam position and profile monitoring provided by the present invention, the current integration unit includes an integration capacitor and an operational amplifier, wherein: The integration capacitor is arranged between the inverting input end and the output end of the operational amplifier. The charging charge amount of the integration capacitor in the charging state is equal to the discharging charge amount of the integration capacitor in the discharging state. The output terminal of the operational amplifier is connected to the first input terminal of the comparator unit, and the operational amplifier is used to determine the current integration voltage signal corresponding to the current input signal.

[0009] According to the multi-channel electronics system for beam position and profile monitoring provided by the present invention, the analog signal acquisition front end further includes a level conversion unit and an optical signal transmitting module, wherein: The level conversion unit is connected to the pulse sequence generator, the optical signal transmitting module, and the digital signal processing backend, and the level conversion unit is used to convert the initial voltage pulse signal into a target voltage pulse signal; The optical signal transmitting module is used to convert the target voltage pulse signal into a target optical signal.

[0010] According to the multi-channel electronics system for beam position and profile monitoring provided by the present invention, the digital signal processing backend determines the average input current corresponding to each channel based on the number of signals corresponding to the target voltage pulse signal or the target optical signal output by each channel, the constant charge amount discharged by each channel during the charge and discharge cycle, and the acquisition period, including: Obtain the constant current corresponding to the constant current source unit and the pulse width corresponding to the initial voltage pulse signal; Based on the constant current and the pulse width, determine the constant charge amount; Determine the ratio of the number of signals to the acquisition period; Based on the constant charge amount and the ratio, determine the average input current corresponding to each channel.

[0011] According to the multi-channel electronics system for beam position and profile monitoring provided by the present invention, the digital signal processing backend determines the beam position and profile monitoring result during the acquisition period based on the average input current corresponding to each channel in the analog signal acquisition front end, including: Arrange the average input current corresponding to each channel according to the relative positions of the channels in the strip ionization chamber to obtain an arrangement result; Based on the arrangement result, determine the beam position and profile monitoring result during the acquisition period.

[0012] According to the multi-channel electronics system for beam position and profile monitoring provided by the present invention, the digital signal processing backend includes a Zynq module and an optical signal receiving module, wherein: The optical signal receiving module is connected to the optical signal transmitting module and the Zynq module, and the optical signal receiving module is used to receive the target optical signal sent by the optical signal transmitting module; The Zynq module is also connected to the level conversion unit. The Zynq module is configured to receive the target voltage pulse signal and the target optical signal, and determine the signal quantity of the target voltage pulse signal or the target optical signal; based on the signal quantity corresponding to the target voltage pulse signal or the target optical signal output by each channel, the constant charge quantity discharged by each channel during the charge and discharge cycle, and the acquisition period, determine the average input current corresponding to each channel; based on the average input current corresponding to each of all channels in the analog signal acquisition front end, determine the beam position and profile monitoring result during the acquisition period.

[0013] The present invention also provides a beam position and profile monitoring method, which is applied to the multi-channel electronics system for beam position and profile monitoring as described in any one of the above. The method includes: Receiving the target voltage pulse signal and the target optical signal corresponding to the current input signal in the channel determined by the analog signal acquisition front end; the current input signal is sent by the strip ionization chamber; the charge quantity of the integration capacitor in the analog signal acquisition front end is dynamically conserved during the charge and discharge cycle. Based on the signal quantity corresponding to the target voltage pulse signal or the target optical signal output by each channel, the constant charge quantity discharged by each channel during the charge and discharge cycle, and the acquisition period, determine the average input current corresponding to each channel; Based on the average input current corresponding to each of all channels, determine the beam position and profile monitoring result during the acquisition period.

[0014] The present invention also provides a beam position and profile monitoring system, including a strip ionization chamber, a host computer, and the multi-channel electronics system for beam position and profile monitoring as described in any one of the above. The strip ionization chamber, the multi-channel electronics system, and the host computer are connected in series in sequence.

[0015] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the computer program, the beam position and profile monitoring method as described in any one of the above is implemented.

[0016] The present invention also provides a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the beam position and profile monitoring method as described in any one of the above is implemented.

[0017] The present invention also provides a computer program product, including a computer program. When the computer program is executed by a processor, the beam position and profile monitoring method as described in any one of the above is implemented.

[0018] The multi-channel electronics system and monitoring method for beam position and profile monitoring provided by the present invention integrate the current input signals sent by the strip ionization chamber through each channel in the analog signal acquisition front-end to obtain the target voltage pulse signals and target optical signals corresponding to the current input signals in the respective channels. The digital signal processing back-end determines the average input current corresponding to each channel according to the number of signals corresponding to the target voltage pulse signals or target optical signals output by each channel, the constant charge amount discharged by each channel during the charge and discharge cycle, and the acquisition period, and determines the beam position and profile monitoring result during the acquisition time according to the average input current corresponding to each channel in the analog signal acquisition front-end. In the present invention, the law of dynamic conservation of charge amount of the integration capacitor in the analog signal acquisition front-end during the charge and discharge cycle is utilized to ensure that charge is not lost and the current integration during the charge and discharge cycle is not interrupted, ensuring a large input dynamic range. At the same time, the digital signal processing back-end determines the beam position and profile monitoring result by using the current-frequency conversion method, improves the intensity of the acquired current signal without sacrificing the passband bandwidth, and further improves the measurement accuracy of the beam position and profile. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0020] Figure 1 It is a schematic structural diagram of the multi-channel electronics system provided by the embodiment of the present invention.

[0021] Figure 2 It is a schematic structural diagram of the analog signal acquisition front-end provided by the embodiment of the present invention.

[0022] Figure 3 It is a schematic connection diagram of the digital signal processing back-end provided by the embodiment of the present invention.

[0023] Figure 4 It is a schematic flow diagram of the beam position and profile monitoring method provided by the embodiment of the present invention.

[0024] Figure 5 It is a schematic structural diagram of the beam position and profile monitoring system provided by the embodiment of the present invention.

[0025] Figure 6 It is a schematic structural diagram of the Zynq module provided by the embodiment of the present invention.

[0026] Reference Signs: 100: Multi-channel electronics system; 110: Analog signal acquisition front-end; 111: Current integration unit; 112: Comparator unit; 113: Pulse sequence generator; 114: Controllable switch unit; 115: Constant current source unit; 116: Level conversion unit; 117: Optical signal emission module; 120: Digital signal processing backend; 121: Zynq module; 122: Optical signal reception module; 200: Strip ionization chamber; 300: Host computer. Detailed implementation manner

[0027] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below with reference to the accompanying drawings in the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without making creative efforts shall fall within the protection scope of the present invention.

[0028] Aiming at the problems of low measurement accuracy and inability to meet a large input dynamic range in the prior art, an embodiment of the present invention provides a multi-channel electronics system for beam position and profile monitoring, hereinafter collectively referred to as the multi-channel electronics system. Figure 1 is a schematic structural diagram of the multi-channel electronics system provided by an embodiment of the present invention. As Figure 1 shown, the multi-channel electronics system 100 includes: an analog signal acquisition front-end 110 and a digital signal processing backend 120.

[0029] The analog signal acquisition front-end 110 includes multiple channels for collecting current input signals. Each channel is used to integrate the current input signals sent by the strip ionization chamber to obtain a target voltage pulse signal and a target optical signal corresponding to the current input signals in each channel.

[0030] The digital signal processing backend 120 is used to determine the average input current corresponding to each channel based on the number of signals corresponding to the target voltage pulse signal or the target optical signal output by each channel, the constant charge amount discharged by each channel during the charge and discharge cycle, and the acquisition period; based on the average input currents corresponding to all channels in the analog signal acquisition front-end 110, determine the beam position and profile monitoring results during the acquisition period; the integration capacitor C1 in the analog signal acquisition front-end 110 has dynamic charge conservation during the charge and discharge cycle.

[0031] Specifically, in the multi-channel electronics system 100, the analog signal acquisition front-end 110 includes multiple channels for acquiring weak current input signals, which correspond one-to-one with multiple output channels in the strip ionization chamber. For example, the analog signal acquisition front-end 110 includes 128 channels for acquiring weak current input signals, and the channel i in the analog signal acquisition front-end 110 receives the current input signal I i (t) output from the output channel i in the strip ionization chamber. In each channel of the analog signal acquisition front-end 110, the current input signal received in the corresponding channel can be integrated to convert the weak current input signal, which is extremely vulnerable to noise interference, into a target voltage pulse signal and a target optical signal that are not easily affected by noise interference, thereby realizing long-distance transmission of the signal. The process of integrating the current input signal includes the process of the current input signal flowing into the integration capacitor C1 for charging and the process of the integration capacitor C1 discharging. The sum of the charging duration and the discharging duration is the charge-discharge cycle, and this charge-discharge cycle is also a pulse signal cycle corresponding to the current input signal. During a pulse signal cycle, the charge quantity of the integration capacitor C1 remains dynamically conserved, that is, the charge quantity flowing into the integration capacitor C1 during the charging process is equal to the charge quantity flowing out of the integration capacitor C1 during the discharging process. Therefore, there will be no "dead time" during the entire pulse signal cycle, ensuring that the input charge quantity will not be lost due to the charging and discharging of the integration capacitor C1. The integration of the current input signal within a pulse signal cycle will not be interrupted. Therefore, in this application, after the current input signal is integrated and converted into the initial voltage signal and then measured, it can not only achieve a large input dynamic range but also ensure excellent linearity within the entire range. After the analog signal acquisition front-end 110 determines the target voltage pulse signal and the target optical signal corresponding to the current input signal in each channel, it sends the target voltage pulse signal and the target optical signal corresponding to each channel to the digital signal processing back-end 120.

[0032] After that, the digital signal processing back-end 120 can count the target voltage pulse signal or the target optical signal corresponding to each channel, statistically obtain the signal quantity corresponding to the target voltage pulse signal or the target optical signal corresponding to each channel, and calculate the average input current corresponding to each channel based on the signal quantity, the constant charge quantity discharged by each channel during the charge-discharge cycle, and the acquisition time period. Then, based on the average input current corresponding to each channel in the analog signal acquisition front-end 110, the beam position and the profile monitoring result are determined. Compared with the prior art that uses current-voltage conversion technology, when the embodiments of the present invention use current-frequency conversion technology to measure the beam position and profile information, the converted target voltage pulse signal and target optical signal are not affected by external noise interference, and have extremely high stability and excellent signal-to-noise ratio.

[0033] It should be noted that the strip ionization chamber is a radiation detector used to measure the beam position and profile information at the terminal of a particle accelerator. When the beam passes through the strip ionization chamber, the particles in the beam interact with the working gas in the strip ionization chamber to generate ion pairs. The ion pair includes an electron and a positive ion. Under the action of an electric field, the ion pair separates and moves towards the electrodes, thereby accumulating charges on the electrodes to form a weak current input signal. Multiple anode strips are provided in the strip ionization chamber. The anode strips serve as output channels for the current input signal, and all the anode strips correspond one-to-one with the channels in the analog signal acquisition front end 110.

[0034] It should be noted that the beam position and profile monitoring results include the beam position and profile information. Among them, the beam position refers to the specific spatial position of the beam in the particle accelerator or the transmission trajectory line. Since each anode strip corresponds to a specific area in the strip ionization chamber, the current input signals output by each anode strip can be used to measure the signals of the beam at different positions simultaneously. The profile information of the beam refers to the distribution of the beam in the cross-section, and the profile information may include characteristics such as the shape, size, and uniformity of the beam.

[0035] It should be noted that the beam position and profile monitoring results during the acquisition period can be the beam position and profile monitoring results of a single turn, or the beam position and profile monitoring results accumulated over multiple turns during the acquisition period.

[0036] In addition, in the embodiment of the present invention, both the target voltage pulse signal and the target optical signal (i.e., through optical fiber communication) can be transmitted between the analog signal acquisition front end 110 and the digital signal processing backend 120. Therefore, for the convenience of installation and use, the entire multi-channel electronics system 100 can assemble the analog signal acquisition front end 110 and the digital signal processing backend 120 together for use, or to avoid the digital signal processing backend 120, especially the Zynq module 121 therein, from being exposed to high-dose radiation, the two can be used separately, that is, the analog signal acquisition front end 110 is installed in an area with a larger radiation dose, and the digital signal processing backend 120 is installed in an area far from the radiation. The target voltage pulse signal and the target optical signal will not be interfered by long-distance transmission, thereby improving the reliability of the system and the accuracy of the monitoring results.

[0037] In addition, the multi-channel electronics system 100 also includes an AC / DC (Alternating Current / Direct Current) power supply, which is used to convert the commercial power AC220V into the DC power required in the multi-channel electronics system 100.

[0038] Furthermore, Figure 2is one of the structural schematic diagrams of the analog signal acquisition front end provided by the embodiments of the present invention. As Figure 2 shown, each of the channels includes a current integration unit 111, a comparator unit 112, a pulse sequence generator 113, and a controllable switch unit 114, where: The first input end of the current integration unit 111 is connected to the strip ionization chamber and the controllable switch unit 114. The second input end of the current integration unit 111 is grounded, and the output end of the current integration unit 111 is connected to the first input end of the comparator unit 112. The current integration unit 111 is configured to receive the current input signal sent by the strip ionization chamber and determine the current integration voltage signal corresponding to the current input signal in the corresponding channel. The output end of the comparator unit 112 is connected to the pulse sequence generator 113. The comparator unit 112 is configured to compare a preset voltage threshold with the current integration voltage signal to obtain a comparison signal. The pulse sequence generator 113 is further connected to the controllable switch unit 114 and is configured to determine an initial voltage pulse signal based on the comparison signal. The pulse width of the initial voltage pulse signal is fixed, and the initial voltage pulse signal is used to control the on-off state of the controllable switch unit 114. The on-off state of the controllable switch unit 114 is used to control the charge change state of the integration capacitor C1 in the current integration unit 111.

[0039] Specifically, each channel in the analog signal acquisition front end 110 includes a current integration unit 111, a comparator unit 112, a pulse sequence generator 113, and a controllable switch unit 114. Among them, the current integration unit 111 can adopt an active integration circuit and is configured to integrate the input current input signal to obtain a corresponding current integration voltage signal. The integration process includes the charging process of the input current signal flowing into the integration capacitor C1 in the current integration unit 111 and the discharging process of the integration capacitor C1. During the charging process, the voltage across the integration capacitor C1 gradually rises to form an integration voltage, and the integration voltage can be expressed as , where represents the integration voltage, and C represents the capacitance value of the integration capacitor C1. When the circuit in this channel reaches a stable state and the integration time is short enough, that is, the period of a pulse signal is extremely short, the integration process of the integration voltage across the integration capacitor C1 during the charging process can be approximated as a linear process. That is, there is an approximate linear relationship between the voltage change amount across the integration capacitor C1 during the charging process and the average input current of the corresponding channel. The specific approximate linear relationship can be expressed as: , where represents the voltage change amount of the integration voltage across the integration capacitor C1 during the charging process, I in represents the average input current of the corresponding channel, and Tc It represents the charging duration of the integrating capacitor C1 within one pulse signal period. After obtaining the current integrating voltage signal, the current integrating unit 111 sends the current integrating voltage signal to the comparator unit 112.

[0040] The comparator unit 112 is used to compare the voltage value corresponding to the current integrating voltage signal with a preset voltage threshold. When the voltage value corresponding to the current integrating voltage signal is less than the preset voltage threshold, the comparison signal input to the comparator is a high-level signal; when the voltage value corresponding to the current integrating voltage signal is greater than the preset voltage threshold, the comparison signal input to the comparator is a low-level signal. When the comparison signal output by the comparator unit 112 flips from a low-level signal to a high-level signal, a rising edge signal is generated, and this rising edge signal serves as the trigger signal for the pulse sequence generator 113, which can control the pulse sequence generator 113 to generate an initial voltage pulse signal with a fixed pulse width. The output terminal of the pulse sequence generator 113 is also connected to the control terminal of the controllable switch unit 114. The level state of the initial voltage pulse signal can control the on-off state of the controllable switch unit 114. For example, when the initial voltage pulse signal is a high-level signal, the controllable switch unit 114 can be controlled to be in an off state; when the initial voltage pulse signal is a low-level signal, the controllable switch power supply can be controlled to be in a closed state.

[0041] In the default state, the controllable switch unit 114 is in an off state. When the controllable switch unit 114 is in an off state, the current input signal of the corresponding channel flows into the integrating capacitor C1 in the current integrating unit 111, that is, the integrating capacitor C1 is in a charging state. When the controllable switch unit 114 is in a closed state, the integrating capacitor C1 in the current integrating unit 111 is in a discharging state.

[0042] In addition, when generating the initial voltage pulse signal, the pulse sequence generator 113 also generates an anti-signal with a phase opposite to that of the initial voltage pulse signal. This anti-signal can be used for timing control, or as a reset signal or a trigger signal for other devices, or for logical operations and signal processing, or for fault detection, etc. The embodiments of the present invention do not limit this.

[0043] It should be noted that, to improve the system stability and anti-interference ability, the comparator unit 112 in the embodiments of the present invention preferably adopts a hysteresis comparator structure.

[0044] Furthermore, as Figure 2As shown, the analog signal acquisition front-end 110 further includes a constant current source unit 115. The constant current source unit 115 is connected to the controllable switch unit 114. When the controllable switch unit 114 is in the closed state, the constant current source unit 115 is connected to the first input end of the current integration unit 111, and the constant current source unit 115 controls the integration capacitor C1 to be in the discharging state.

[0045] Specifically, when the pulse sequence generator 113 controls the controllable switch unit 114 to be in the closed state, the constant current source unit 115 is connected to the current integration unit 111. At this time, since the constant current in the constant current source unit 115 is greater than the maximum current input current sent by the strip ionization chamber. According to Kirchhoff's current law, during the duration of the initial voltage pulse signal which is a low-level signal, there is a current flowing outwards along the conduction path of the controllable switch unit 114 on the integration capacitor C1 in the current integration unit 111. At this time, it can be regarded as the constant current in the constant current source unit 115 discharging the integration capacitor C1 in the current integration unit 111. Similar to the charging process, when the circuit reaches the steady state, due to the extremely short pulse signal period, the integration process on the integration capacitor C1 during the discharging process can be approximated as a linear process, that is, after determining the current difference between the constant current and the average input current during the discharging process, there is an approximate linear relationship between the voltage change amount across the integration capacitor C1 and the current difference during the discharging process. This approximate linear relationship can be specifically expressed as: . Wherein, I ref represents the constant current in the constant current source unit 115, and T w represents the pulse width of the initial voltage pulse signal, that is, the discharging duration of the integration capacitor C1 within one pulse signal period.

[0046] Furthermore, as Figure 2 shown, the current integration unit 111 includes an integration capacitor C1 and an operational amplifier Q, where: The integration capacitor C1 is arranged between the inverting input end and the output end of the operational amplifier Q. The charging charge amount of the integration capacitor C1 in the charging state is equal to the discharging charge amount of the integration capacitor C1 in the discharging state; The output end of the operational amplifier Q is connected to the first input end of the comparator unit 112. The operational amplifier Q is used to determine the current integration voltage signal corresponding to the current input signal.

[0047] Furthermore, as Figure 2 shown, the analog signal acquisition front-end 110 further includes a level conversion unit 116 and an optical signal transmitting module 117, where: The level conversion unit 116 is connected to the pulse sequence generator 113, the optical signal transmitting module 117, and the digital signal processing backend 120. The level conversion unit 116 is configured to convert the initial voltage pulse signal into a target voltage pulse signal; The optical signal transmitting module 117 is configured to convert the target voltage pulse signal into a target optical signal.

[0048] Specifically, after the pulse sequence generator 113 generates an initial voltage pulse signal with a fixed pulse width, the initial voltage pulse signal can be converted into a target voltage pulse signal that can be directly collected and counted by the digital signal processing backend 120, and the target voltage pulse signal is respectively sent to the digital signal processing unit and the optical signal transmitting module 117. After receiving the target voltage pulse signal, the optical signal transmitting module 117 can convert the target voltage pulse signal into a target optical signal.

[0049] It should be noted that the level conversion unit 116 is powered by a dual-power supply. The input voltage of the level conversion unit 116 and the pulse sequence generator 113 use the same power supply, and the output power supply of the level conversion unit 116 is the same as the power supply for powering the Zynq module 121 in the digital signal processing backend 120.

[0050] Further, the digital signal processing backend 120 determines the average input current corresponding to each channel based on the signal quantity corresponding to the target voltage pulse signal or the target optical signal output by each channel, the constant charge quantity discharged by each channel during the charge and discharge cycle, and the acquisition period, including: Obtain the constant current corresponding to the constant current source unit 115 and the pulse width corresponding to the initial voltage pulse signal; Determine the constant charge quantity based on the constant current and the pulse width; Determine the ratio of the signal quantity to the acquisition period; Determine the average input current corresponding to each channel based on the constant charge quantity and the ratio.

[0051] Specifically, since the integral capacitor C1 maintains dynamic charge conservation during the charge and discharge cycle, according to the approximate linear relationship during the charging process and the approximate linear relationship during the discharging process, the equation shown in Equation (1) can be obtained. Equation (1) is: .

[0052] After organizing Equation (1), the calculation formula for the average input current corresponding to a single pulse signal period shown in Equation (2) can be obtained. Equation (2) is: .

[0053] where F represents the frequency of the charge-discharge cycle, and .

[0054] During the acquisition period including N pulse signal cycles, the average input current of the channel within the acquisition period is as shown in Equation (3), and Equation (3) is: .

[0055] where T represents the acquisition period.

[0056] Therefore, after determining Equation (3), for each channel, calculate the product of the constant current and the pulse width in this channel, and this product is the constant charge amount. Then calculate the ratio of the number of signals to the acquisition period, and then calculate the product of the constant charge amount and the ratio. This product is the average input current of this channel within the acquisition period. Repeat the above operations to obtain the average input current of each channel in the analog signal acquisition front end 110 corresponding to their respective acquisition periods.

[0057] Furthermore, the digital signal processing backend 120 determines the beam position and profile monitoring results within the acquisition period based on the average input current of each channel in the analog signal acquisition front end 110, including: Arrange the average input current corresponding to each channel according to the relative positions of the channels in the strip ionization chamber to obtain an arrangement result; Based on the arrangement result, determine the beam position and profile monitoring results within the acquisition period.

[0058] Specifically, the average input current corresponding to each channel in the strip ionization chamber indicates the average intensity of the beam on each channel. The channels in the strip ionization chamber are distributed in a certain arrangement order, and the regions corresponding to each channel are fixed. Therefore, after arranging the average input current corresponding to each channel according to the relative positions of the channels, the average input currents of different channels can be compared to determine the beam position. For example, if the average input current of Channel A is the largest, it indicates that the intensity of the beam on Channel A is the largest, and thus it can be determined that the beam approximately appears in Channel A. The average input current arranged according to the channel positions indicates the intensity distribution of the beam on the cross-section of the strip ionization chamber, and this intensity distribution is the profile information. Based on this, the beam position and profile monitoring results can be obtained according to the beam position and profile information. The arrangement result also ensures the continuity and accuracy of the beam position and profile information.

[0059] Furthermore, Figure 3 is the connection schematic diagram of the digital signal processing backend provided by the embodiment of the present invention, as Figure 3 described, the digital signal processing backend 120 includes a Zynq module 121 and an optical signal receiving module 122, where: The optical signal receiving module 122 is connected to the optical signal transmitting module 117 and the Zynq module 121, and the optical signal receiving module 122 is configured to receive the target optical signal transmitted by the optical signal transmitting module 117; The Zynq module 121 is further connected to the level conversion unit 116. The Zynq module 121 is configured to receive the target voltage pulse signal and the target optical signal, and determine the signal quantity of the target voltage pulse signal or the target optical signal; based on the signal quantity corresponding to the target voltage pulse signal or the target optical signal output by each channel, the constant charge quantity discharged by each channel during the charge and discharge cycle, and the acquisition period, determine the average input current corresponding to each channel; based on the average input current corresponding to each channel in the analog signal acquisition front end 110, determine the beam position and the profile monitoring result during the acquisition period.

[0060] Specifically, in the digital signal processing backend 120, after the optical signal receiving module 122 receives the target optical signal transmitted by the optical signal transmitting module 117, it can also forward the target optical signal to the Zynq module 121. While receiving the target voltage pulse signal and the target optical signal, the Zynq module 121 also counts the signal quantity of the target voltage pulse signal or the signal quantity of the target optical signal. Then, the average input current corresponding to each channel can be calculated using Equation (3), and based on the arrangement result corresponding to the average input current of each channel in the analog signal acquisition front end 110, the beam position and the profile monitoring result during the acquisition period are determined.

[0061] It should be noted that the Zynq module 121 refers to a component or module that adopts the Zynq series of System on Chip (SoC) technologies. This Zynq module 121 combines the software programmability of the processor and the hardware programmability of the FPGA (Field Programmable Gate Array), providing users with a flexible hardware or software co-design platform.

[0062] During the operation of the accelerator, since it involves the cooperation of various devices and equipment, and the environmental noise does not exist stably, this environmental noise often changes with the change of the operating state of the accelerator. Therefore, in order to improve the test accuracy of the multi-channel electronics system 100, in the trigger mode, the multi-channel electronics system 100 uses a time-segmented method to deduct the background noise in real time, that is, when there is no beam, a trigger signal is used as the start measurement signal, and the noise errors caused by the environment or the leakage current of the electronics itself in each time period are measured and saved in segments. When there is a real beam, the same trigger signal is used as the start measurement signal, the corresponding noise data saved before is read according to the measured time, and deducted from the measurement result to obtain the real measurement result.

[0063] In addition, after the actual test of the multi-channel electronics system 100 provided in the embodiment of the present invention, it can be known that the multi-channel electronics system 100 has 128 channels and realizes a standardized design, and the number of channels can be increased or decreased accordingly according to the actual use requirements of the strip ionization chamber. The input dynamic range exceeds 126 dB, the minimum current resolution is less than the femtoampere level, and the non-linearity error is less than 10%.

[0064] In the multi-channel electronics system provided by the embodiment of the present invention, each channel in the analog signal acquisition front end 110 integrates the current input signal sent by the strip ionization chamber to obtain the target voltage pulse signal and the target optical signal corresponding to the current input signal in the corresponding channel. The digital signal processing backend 120 determines the average input current corresponding to each channel according to the signal quantity corresponding to the target voltage pulse signal or the target optical signal output by each channel, the constant charge quantity discharged by each channel during the charge and discharge cycle, and the acquisition time period, and determines the beam position and the profile monitoring result during the acquisition time according to the average input current corresponding to each channel in the analog signal acquisition front end 110. In the embodiment of the present invention, by using the law of dynamic conservation of charge quantity of the integration capacitor in the analog signal acquisition front end 110 during the charge and discharge cycle, it is ensured that the charge will not be lost, and the current integration during the charge and discharge cycle will not be interrupted, ensuring a large input dynamic range. At the same time, the digital signal processing backend 120 uses the current-frequency conversion method to determine the beam position and the profile monitoring result, and improves the intensity of the acquired current signal without sacrificing the passband bandwidth, thereby improving the measurement accuracy of the beam position and the profile.

[0065] The embodiment of the present invention also provides a beam position and profile monitoring method, which is applied to the multi-channel electronics system for beam position and profile monitoring as described in any one of the above. Figure 4 It is a schematic flowchart of the beam position and profile monitoring method provided by the embodiment of the present invention, as Figure 4As shown, the method includes the following steps 410 to 430.

[0066] Step 410, receiving a target voltage pulse signal and a target optical signal corresponding to a current input signal in a channel determined by an analog signal acquisition front end; the current input signal is sent by a strip ionization chamber; the charge amount in the integration capacitor in the analog signal acquisition front end is dynamically conserved during the charge and discharge cycle.

[0067] Step 420, determining an average input current corresponding to each channel based on the number of signals corresponding to the target voltage pulse signal or the target optical signal output by each channel, the constant charge amount discharged by each channel during the charge and discharge cycle, and the acquisition period.

[0068] Step 430, determining the beam position and profile monitoring result during the acquisition period based on the average input current corresponding to each of all channels.

[0069] For the beam position and profile monitoring method provided by the embodiments of the present invention, after receiving the target voltage pulse signal and the target optical signal corresponding to the current input signal in the channel obtained by integrating the current input signal sent by the strip ionization chamber by the analog signal acquisition front end, according to the number of signals corresponding to the target voltage pulse signal or the target optical signal output by each channel, the constant charge amount discharged by each channel during the charge and discharge cycle, and the acquisition period, the average input current corresponding to each channel is determined, and based on the average input current corresponding to each of all channels, the beam position and profile monitoring result during the acquisition time is determined. In the embodiments of the present invention, by using the law that the charge amount in the integration capacitor in the analog signal acquisition front end is dynamically conserved during the charge and discharge cycle, it is ensured that the charge will not be lost, and the current integration during the charge and discharge cycle will not be interrupted, ensuring a large input dynamic range. At the same time, the beam position and profile monitoring result is determined by the digital signal processing backend using the current-frequency conversion method, which improves the intensity of the acquired current signal without sacrificing the passband bandwidth, and further improves the measurement accuracy of the beam position and profile.

[0070] The embodiments of the present invention further provide a beam position and profile monitoring system. Figure 5 It is a schematic structural diagram of the beam position and profile monitoring system provided by the embodiments of the present invention. As Figure 5 shown, the beam position and profile monitoring system includes a strip ionization chamber 200, a host computer 300, and a multi-channel electronics system 100 as described in any one of the above. The strip ionization chamber 200, the multi-channel electronics system 100, and the host computer 300 are connected in series in sequence.

[0071] The digital signal processing backend in the multi-channel electronics system 100 has a variety of peripheral interfaces for debugging and testing the multi-channel electronics system 100 and for data transmission and instruction interaction with the host computer 300.

[0072] Figure 6 It is a schematic structural diagram of the Zynq module provided by an embodiment of the present invention. As Figure 6 shown, the electronic device may include: a processor 610, a communications interface 620, a memory 630, and a communication bus 640. Among them, the processor 610, the communications interface 620, and the memory 630 communicate with each other through the communication bus 640. The processor 610 may call the logical instructions in the memory 630 to execute the beam position and profile monitoring method, and the method includes: Receiving a target voltage pulse signal and a target optical signal corresponding to the current input signal in the channel determined by the analog signal acquisition front end; the current input signal is sent by the strip ionization chamber; the charge in the integration capacitor in the analog signal acquisition front end is dynamically conserved during the charge and discharge cycle.

[0073] Based on the number of signals corresponding to the target voltage pulse signal or the target optical signal output by each channel, the constant charge amount discharged by each channel during the charge and discharge cycle, and the acquisition period, determine the average input current corresponding to each channel.

[0074] Based on the average input current corresponding to each of all channels, determine the beam position and profile monitoring result during the acquisition period.

[0075] In addition, when the logical instructions in the above-mentioned memory 630 are implemented in the form of software function units and sold or used as an independent product, they may be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of this technical solution, may be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The foregoing storage medium includes: various media such as a USB flash drive, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk, or an optical disc that can store program codes.

[0076] On the other hand, the present invention also provides a computer program product, which includes a computer program. The computer program can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the beam position and profile monitoring method provided by each of the above methods. The method includes: Receiving a target voltage pulse signal and a target optical signal corresponding to a current input signal in a channel determined by an analog signal acquisition front end; the current input signal is sent by a strip ionization chamber; the charge in the integration capacitor in the analog signal acquisition front end is dynamically conserved during the charge and discharge cycle.

[0077] Based on the number of signals corresponding to the target voltage pulse signal or the target optical signal output by each channel, the constant charge amount discharged by each channel during the charge and discharge cycle, and the acquisition period, determine the average input current corresponding to each channel.

[0078] Based on the average input current corresponding to each of all channels, determine the beam position and profile monitoring result during the acquisition period.

[0079] In another aspect, the present invention also provides a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it is implemented to execute the beam position and profile monitoring method provided by each of the above methods. The method includes: Receiving a target voltage pulse signal and a target optical signal corresponding to a current input signal in a channel determined by an analog signal acquisition front end; the current input signal is sent by a strip ionization chamber; the charge in the integration capacitor in the analog signal acquisition front end is dynamically conserved during the charge and discharge cycle.

[0080] Based on the number of signals corresponding to the target voltage pulse signal or the target optical signal output by each channel, the constant charge amount discharged by each channel during the charge and discharge cycle, and the acquisition period, determine the average input current corresponding to each channel.

[0081] Based on the average input current corresponding to each of all channels, determine the beam position and profile monitoring result during the acquisition period.

[0082] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated. The components shown as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. Those of ordinary skill in the art can understand and implement it without creative labor.

[0083] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the essence of the above technical solution, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0084] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multi-channel electronics system for beam position and profile monitoring, characterized in that, Comprising: An analog signal acquisition front end and a digital signal processing back end, wherein: The analog signal acquisition front end includes multiple channels for acquiring current input signals. Each channel is used to integrate the current input signal sent by the strip ionization chamber to obtain a target voltage pulse signal and a target optical signal corresponding to the current input signal in the channel; The digital signal processing back end is used to determine the average input current corresponding to each channel based on the signal quantity corresponding to the target voltage pulse signal or the target optical signal output by each channel, the constant charge quantity discharged by each channel during the charge and discharge cycle, and the acquisition period; Based on the average input current corresponding to each channel in the analog signal acquisition front end, determine the beam position and profile monitoring result during the acquisition period; the charge quantity of the integration capacitor in the analog signal acquisition front end is dynamically conserved during the charge and discharge cycle.

2. The multi-channel electronics system for beam position and profile monitoring according to claim 1, wherein Each channel includes a current integration unit, a comparator unit, a pulse sequence generator, and a controllable switch unit, wherein: The first input end of the current integration unit is connected to the strip ionization chamber and the controllable switch unit. The second input end of the current integration unit is grounded, and the output end of the current integration unit is connected to the first input end of the comparator unit. The current integration unit is used to receive the current input signal sent by the strip ionization chamber and determine the current integration voltage signal corresponding to the current input signal in the channel; The output end of the comparator unit is connected to the pulse sequence generator. The comparator unit is used to compare a preset voltage threshold with the current integration voltage signal to obtain a comparison signal; The pulse sequence generator is also connected to the controllable switch unit and is used to determine an initial voltage pulse signal based on the comparison signal. The pulse width of the initial voltage pulse signal is fixed, and the initial voltage pulse signal is used to control the on / off state of the controllable switch unit. The on / off state of the controllable switch unit is used to control the change state of the charge quantity of the integration capacitor in the current integration unit.

3. The multi-channel electronics system for beam position and profile monitoring according to claim 2, wherein The analog signal acquisition front end further includes a constant current source unit. The constant current source unit is connected to the controllable switch unit. When the controllable switch unit is in the closed state, the constant current source unit is connected to the first input end of the current integration unit, and the constant current source unit controls the integration capacitor to be in the discharge state.

4. The multi-channel electronics system for beam position and profile monitoring according to claim 2, wherein The current integration unit includes an integration capacitor and an operational amplifier, wherein: The integration capacitor is arranged between the inverting input end and the output end of the operational amplifier. The charging charge quantity of the integration capacitor in the charging state is equal to the discharging charge quantity of the integration capacitor in the discharging state; The output end of the operational amplifier is connected to the first input end of the comparator unit. The comparator unit is used to determine the current integration voltage signal corresponding to the current input signal.

5. The multi-channel electronics system for beam position and profile monitoring according to claim 2, wherein The analog signal acquisition front end further includes a level conversion unit and an optical signal emission module, wherein: The level conversion unit is connected to the pulse sequence generator, the optical signal transmitting module, and the digital signal processing backend. The level conversion unit is configured to convert the initial voltage pulse signal into a target voltage pulse signal; The optical signal transmitting module is configured to convert the target voltage pulse signal into a target optical signal.

6. The multi-channel electronics system for beam position and profile monitoring according to claim 3, wherein The digital signal processing backend determines the average input current corresponding to each channel based on the signal quantity corresponding to the target voltage pulse signal or the target optical signal output by each channel, the constant charge quantity discharged by each channel during the charge and discharge cycle, and the acquisition period, including: Obtaining the constant current corresponding to the constant current source unit and the pulse width corresponding to the initial voltage pulse signal; Determining the constant charge quantity based on the constant current and the pulse width; Determining the ratio of the signal quantity to the acquisition period; Determining the average input current corresponding to each channel based on the constant charge quantity and the ratio.

7. The multi-channel electronics system for beam position and profile monitoring according to claim 1, characterized in that, The digital signal processing backend determines the beam position and profile monitoring result during the acquisition period based on the average input current corresponding to each channel in the analog signal acquisition front end, including: Arranging the average input current corresponding to each channel according to the relative positions of the channels in the strip ionization chamber to obtain an arrangement result; Determining the beam position and profile monitoring result during the acquisition period based on the arrangement result.

8. The multi-channel electronics system for beam position and profile monitoring according to claim 5, characterized in that, The digital signal processing backend includes a Zynq module and an optical signal receiving module, wherein: The optical signal receiving module is connected to the optical signal transmitting module and the Zynq module. The optical signal receiving module is configured to receive the target optical signal sent by the optical signal transmitting module; The Zynq module is further connected to the level conversion unit. The Zynq module is configured to receive the target voltage pulse signal and the target optical signal, and determine the signal quantity of the target voltage pulse signal or the target optical signal; determine the average input current corresponding to each channel based on the signal quantity corresponding to the target voltage pulse signal or the target optical signal output by each channel, the constant charge quantity discharged by each channel during the charge and discharge cycle, and the acquisition period; determine the beam position and profile monitoring result during the acquisition period based on the average input current corresponding to each channel in the analog signal acquisition front end.

9. A beam position and profile monitoring method, characterized in that, Applied to the multi-channel electronics system for beam position and profile monitoring according to any one of claims 1-8, the method includes: Receiving the target voltage pulse signal and the target optical signal corresponding to the current input signal in the determined channel of the analog signal acquisition front end; the current input signal is sent by the strip ionization chamber; the charge quantity of the integration capacitor in the analog signal acquisition front end is dynamically conserved during the charge and discharge cycle; Determining the average input current corresponding to each channel based on the signal quantity corresponding to the target voltage pulse signal or the target optical signal output by each channel, the constant charge quantity discharged by each channel during the charge and discharge cycle, and the acquisition period; Based on the average input current corresponding to each channel, determine the beam position and profile monitoring results during the acquisition period.

10. A beam position and profile monitoring system, characterized in that, It includes a strip ionization chamber, a host computer, and a multi-channel electronics system for beam position and profile monitoring according to any one of claims 1-8, and the strip ionization chamber, the multi-channel electronics system, and the host computer are connected in series in sequence.

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