Radio frequency signal control device and method and related equipment

Abstract

The invention discloses a radio frequency signal control device and method and related equipment, and relates to the technical field of radiotherapy, and the device comprises a main control module which is used for the execution of radio frequency signal control logic, and is used for collecting the signal of a radio frequency cavity and the incident power and reflection power of a directional coupler in real time, and feeding back the power to the main control module, the signal of the radio frequency cavity comprises D box power; the phase detection module is used for detecting the phase error of the incident power and the D box power in real time and generating an oscillation driving signal during phase matching; the amplification module is used for amplifying the oscillation driving signal; and the base signal generation module is used for generating a radio frequency base signal according to the received oscillation driving signal so as to realize closed-loop control of a radio frequency signal of the synchrocyclotron and realize stable and efficient acceleration of a proton beam in the synchrocyclotron system.

Description

Technical Field

[0001] The present invention relates to the field of radiotherapy technology, and in particular to a radio frequency signal control device, method and related equipment. Background Art

[0002] Particle accelerators are important equipment in the field of radiotherapy, used to accelerate charged particles to high energy. Among them, cyclotron accelerators are an important type, which accelerate charged particles by using alternating voltage and one or more "D-shaped boxes" (the name of the D-shaped electrodes in early cyclotron accelerators) in a vacuum chamber. These particles move in an axial magnetic field and produce a spiral track perpendicular to the magnetic field; when the particles spiral outward, the accelerating electric field is applied to the gap between the D-shaped boxes.

[0003] In a cyclotron, the spiral orbits produced by accelerated particles are perpendicular to the magnetic field, and an accelerating electric field is applied across the gaps between the dees as the particles spiral outward. A radio frequency (RF) voltage produces an alternating electric field across the gaps between the dees, which is synchronized with the orbital period of the charged particles in the magnetic field, causing the particles to be accelerated by the RF waveform as they repeatedly cross these gaps.

[0004] However, as the particle energy increases, relativistic effects become significant. However, when the particle energy increases to energy levels far beyond what can be accelerated by the applied radio frequency (RF) peak voltage, that is, when the speed of the charged particle approaches the speed of light, its mass increases, causing the acceleration to become inconsistent and the time at which the particle arrives at the gap is no longer synchronized with the peak of the applied voltage. The acceleration process becomes complicated. To overcome this challenge, two types of cyclotrons have been developed: isochronous cyclotrons and synchrocyclotrons.

[0005] Isochronous cyclotrons gradually increase the magnetic field strength as the radius increases, while using a constant voltage frequency to maintain synchronization during the acceleration process. However, this approach limits the highest energy that can be achieved because as the particle energy increases, the required magnetic field strength also increases, which may be difficult to achieve in practical applications.

[0006] In contrast, synchrocyclotrons use a magnetic field that tapers off as radius increases and a varying frequency of the accelerating voltage, with discrete "strings" of charged particles accelerated to a final energy to match the increase in mass caused by the particles' relativistic speeds before the cycle begins again. This approach allows charged particles to be accelerated to higher energy levels.

[0007] However, the RF control system of the synchrocyclotron faces many challenges and requires an improved control system to precisely adjust the magnetic field strength and the frequency of the RF voltage. Summary of the invention

[0008] Based on the above problems, the purpose of the present invention is to provide a radio frequency signal control device, method and related equipment, through an efficient radio frequency signal control device and method, and an ion source automatic beam tuning method, to achieve closed-loop control of the radio frequency signal of a synchrocyclotron accelerator, and to achieve stable and efficient acceleration of the proton beam in the synchrocyclotron accelerator system.

[0009] The purpose of the present invention is achieved by the following technical solutions:

[0010] In a first aspect, the present invention provides a radio frequency signal control device for realizing closed-loop control of a radio frequency signal of a synchrocyclotron accelerator, the device comprising:

[0011] The main control module is used for executing the RF signal control logic, including receiving sampling signals, signal processing and feedback adjustment;

[0012] A sampling module is used to collect the signal of the radio frequency cavity and the incident power and reflected power on the directional coupler in real time and feed them back to the main control module. The signal of the radio frequency cavity includes the D-box power.

[0013] A phase detection module, used to detect the phase error between the incident power and the D-box power in real time, and generate an oscillation drive signal when the phases match;

[0014] an amplifying module, used for amplifying the oscillation driving signal;

[0015] The base signal generating module is used to generate a radio frequency base signal according to the received oscillation driving signal to ensure that the frequency and phase of the radio frequency signal match the requirements of the synchrocyclotron accelerator.

[0016] Preferably, the driving signal of the phase detection module is directly amplified by a signal amplification module, and then drives the base signal generation module to generate a radio frequency base signal.

[0017] Preferably, the device further comprises an analog-to-digital conversion module and a digital-to-analog conversion module; the analog-to-digital conversion module is used to perform analog-to-digital conversion on the oscillation drive signal; the digital-to-analog conversion module is used to convert the digital signal into an analog signal;

[0018] The driving signal of the phase detection module is converted into a digital signal by the analog-to-digital conversion module and then enters the main control module. After being processed by the main control module, it is converted into digital and amplified, and finally drives the base signal generation module to generate a radio frequency base signal.

[0019] Preferably, the device further comprises a calibration module, and the calibration module is used to calibrate the frequency points of the radio frequency scanning cycle through the radio frequency power signal;

[0020] The radio frequency power signal includes radio frequency on, radio frequency off and ion source on; the calibration module controls the radio frequency power on time interval and the ion source on time in each scanning cycle.

[0021] Preferably, the device also includes an amplitude modulation module for adjusting the gain of the RF base signal; the amplitude modulation module includes a step attenuator and a digitally adjustable gain device, the RF base signal is attenuated by the step attenuator, and the attenuated signal is amplified again by the digitally adjustable gain device.

[0022] Preferably, the amplitude modulation module further comprises a time slice division unit, which is used to divide the power amplification time interval into a plurality of time slices and control the loaded gain signal in each time slice.

[0023] Preferably, the device further comprises a remote interaction module, through which the amplitude gain of the digital adjustable gain device is controlled.

[0024] Preferably, the device further comprises a fixed attenuator and / or a hardware safety interlocking module, wherein the fixed attenuator is used to limit the maximum output amplitude of the radio frequency signal;

[0025] The hardware safety interlocking module is used to safely cut off the radio frequency signal; or send the modulated radio frequency signal to the radio frequency amplifier.

[0026] In a second aspect, the present invention provides a radio frequency system, wherein the radio frequency system is used to implement ion acceleration control of a synchrocyclotron accelerator, and the system comprises:

[0027] A radio frequency power amplifier, used to amplify the input low-amplitude radio frequency signal by a fixed gain multiple and then output it into the radio frequency cavity;

[0028] RF cavity, used for RF signal transmission and proton bunch energy conversion;

[0029] Any of the RF signal control devices described in the present invention is used to obtain a sampling signal, provide real-time feedback of a power value and a phase error, and generate a driving signal based on the power value and the phase error to control the operation of the RF power amplification device and the RF cavity, thereby achieving closed-loop control of the RF signal.

[0030] In a third aspect, the present invention provides a particle radiation therapy system, comprising:

[0031] an ion source for generating an ion beam;

[0032] The radio frequency system of the present invention is used for providing radio frequency signals to generate an accelerating electric field for accelerating an ion beam to a desired energy level.

[0033] In a fourth aspect, the present invention provides a radio frequency signal control method for realizing closed-loop control of a radio frequency signal of a synchrocyclotron accelerator, wherein the method is realized by any radio frequency signal control device of the present invention, and comprises:

[0034] Real-time acquisition of the signal of the radio frequency cavity and the incident power and the reflected power on the directional coupler, wherein the signal of the radio frequency cavity includes the D-box power;

[0035] detecting the phase error between the incident power and the D-box power in real time, and generating an oscillating driving signal when the phases match;

[0036] The base signal generating module is driven by the driving signal to obtain a radio frequency base signal.

[0037] Preferably, in the radio frequency signal control method, the step of driving a base signal generating module with the driving signal to obtain a radio frequency base signal comprises:

[0038] The driving signal is directly amplified to drive the base signal generating module to obtain a radio frequency base signal.

[0039] Preferably, in the radio frequency signal control method, the step of driving a base signal generating module with the driving signal to obtain a radio frequency base signal comprises:

[0040] The driving signal is converted into a digital signal by the analog-to-digital conversion module and then enters the main control module. After being processed by the main control chip, it is converted into digital and amplified, and finally drives the base signal generation module to generate a radio frequency base signal.

[0041] Preferably, the radio frequency signal control method further comprises:

[0042] The frequency point of the radio frequency scanning cycle is calibrated by the radio frequency power signal; the radio frequency power signal includes turning on the radio frequency, turning off the radio frequency and turning on the ion source;

[0043] In each scanning cycle, the on-time interval of the RF power and the on-time of the ion source are controlled.

[0044] Preferably, the radio frequency signal control method further comprises:

[0045] The gain of the radio frequency base signal is adjusted by an amplitude modulation module, wherein the amplitude modulation module includes a step attenuator and a digital adjustable gain device, the radio frequency base signal is attenuated by the step attenuator, and the attenuated signal is amplified again by the digital adjustable gain device;

[0046] The power amplification time interval is divided into multiple time slices, and the loaded gain signal is controlled in each time slice;

[0047] The amplitude gain of the digital adjustable gain amplifier is controlled by the remote interaction module.

[0048] Preferably, the radio frequency signal control method further comprises:

[0049] Limiting the maximum output amplitude of the RF signal by a fixed attenuator;

[0050] It is determined whether the modulated RF signal meets the preset conditions. If so, the modulated RF signal is sent to the RF amplifier; if not, the RF signal is safely cut off.

[0051] In a fifth aspect, the present invention provides an ion source automatic beam adjustment method, which is applicable to the particle radiation therapy system of the present invention, and the method comprises:

[0052] Setting initialization parameters, including frequency parameters of a radio frequency power signal, so that the accelerator can operate stably; wherein the radio frequency power signal includes turning on the radio frequency, turning off the radio frequency, and turning on the ion source;

[0053] Monitor and adjust multiple control parameters in real time to obtain the optimal control parameter combination;

[0054] Under the optimal control parameter combination, the change amount of each control parameter before and after adjustment and the performance change of the proton beam are obtained; according to the change amount of each parameter before and after adjustment and the performance change of the proton beam, a pulse width charge test is performed;

[0055] The optimal adjustment parameters and adjustment amount are obtained through the test results; and automatic beam adjustment is achieved through the optimal adjustment parameters and adjustment amount.

[0056] Preferably, the real-time monitoring and adjusting of control parameters; obtaining an optimal control parameter combination includes:

[0057] Adjusting the DC bias voltage to suppress secondary electron emission;

[0058] After the DC bias voltage is regulated, the amplitude modulation value is adjusted and the hydrogen flow rate is adjusted synchronously;

[0059] Adjusts the adaptive coil position and operating frequency of the rotary capacitor motor;

[0060] The optimal control parameter combination is obtained by adjusting the results.

[0061] Preferably, the real-time monitoring and adjusting of control parameters; obtaining an optimal control parameter combination includes:

[0062] Through historical data, the influence curve of each control parameter on each beam characteristic is obtained;

[0063] According to the influence curve of each control parameter on each beam characteristic, a first adjustment range of each control parameter is set;

[0064] Within the first adjustment range, a plurality of continuous control points are set for each control parameter;

[0065] By continuously controlling the points and adjusting the control parameters, the real-time beam characteristic change trend can be obtained;

[0066] Obtaining a second adjustment range of each control parameter through a real-time beam characteristic change trend;

[0067] Within the second adjustment range, adjust each control point of each control parameter one by one;

[0068] Real-time monitoring of the values ​​of relevant control parameters before and after adjustment, and by comparing the beam characteristics under different parameter combinations, determining further adjustment parameters and adjustment amounts;

[0069] The optimal control parameter combination is obtained through iterative adjustment.

[0070] In a sixth aspect, the present invention provides an electronic device, comprising a memory and a processor, wherein the memory stores a computer program, and the processor implements the functions of any device described in the present invention or performs the steps of any method described in the present invention when executing the computer program.

[0071] In a seventh aspect, the present invention provides a computer-readable storage medium, wherein the storage medium stores computer instructions. When a computer reads the computer instructions, the computer implements the functions of the device as described in any one of the present invention or executes the steps of any one of the methods as described in the present invention.

[0072] Compared with the prior art, the beneficial effects of the present invention include at least: the closed-loop control link can monitor the amplitude and phase of the RF signal in real time, accurately adjust the output of the RF signal through the feedback mechanism, and ensure the stability and accuracy of the RF signal during transmission, which helps to reduce the measurement error of the pulse width charge (Pulse Width Charge) and improve the measurement accuracy. The introduction of analog-to-digital conversion and digital-to-analog conversion modules enables the system to process digital signals, enhances the flexibility and programmability of the system, and facilitates subsequent functional expansion and optimization. The calibration module can accurately calibrate the frequency points of the RF scanning cycle, control the RF power and the opening time of the ion source, and improve the control accuracy and efficiency of the system; the amplitude modulation module realizes the precise adjustment of the RF base signal gain through the step attenuator and the digital adjustable gain, and improves the output performance and stability of the system. The setting of the fixed attenuator and the hardware safety interlocking module ensures that the maximum output amplitude of the RF signal is within the safe range and meets the safety interlocking design requirements of medical regulations, preventing the system from being overloaded or damaged or the RF signal from being turned on by mistake. The RF cavity adopts a three-quarter wavelength cavity design, which can efficiently convert energy within the RF signal range of 85MHz to 133.5MHz, providing a stable electric field for ion acceleration. Combined with the RF signal control device, closed-loop control of the RF signal is achieved, which improves the stability and control accuracy of the system and ensures the stability and reliability of the ion acceleration process. The automatic beam tuning algorithm can automatically adjust the operating parameters of the accelerator according to the real-time performance parameters of the beam to optimize the output of the beam, which helps to improve the beam current intensity, because more optimized operating parameters can accelerate the ion beam more effectively; the automatic beam tuning algorithm can monitor the quality parameters of the beam (such as beam spot size, beam divergence angle, etc.) in real time, and automatically adjust the operating parameters of the accelerator according to these parameters, which helps to reduce beam loss and scattering and improve the quality of the beam. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] Figure 1 is a schematic diagram of a radio frequency signal control device according to an embodiment of the present invention;

[0074] Figure 2 is a schematic diagram of a radio frequency system according to an embodiment of the present invention;

[0075] Figure 3 is a schematic diagram of a radio frequency power amplification device according to an embodiment of the present invention;

[0076] Figure 4 is a schematic diagram of a radio frequency signal control method according to an embodiment of the present invention;

[0077] Figure 5 is a schematic diagram of an ion source automatic beam adjustment method according to an embodiment of the present invention;

[0078] Figure 6It is a schematic flow chart of an ion source automatic beam adjustment method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0079] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided to make the present invention more comprehensive and complete and to fully convey the concepts of example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their repeated description will be omitted.

[0080] The words expressing positions and directions described in the present invention are all explained with reference to the accompanying drawings as examples, but they can be changed as needed, and all such changes are included in the protection scope of the present invention.

[0081] Refer to the attached Figure 1 The embodiment of the present invention provides a radio frequency signal control device for realizing closed-loop control of radio frequency signals of a synchrocyclotron accelerator, characterized in that the device comprises:

[0082] The main control module is used for executing the RF signal control logic, including receiving sampling signals, signal processing and feedback adjustment;

[0083] A sampling module is used to collect the signal of the radio frequency cavity and the incident power and reflected power on the directional coupler in real time and feed them back to the main control module. The signal of the radio frequency cavity includes the power of the D box, i.e., the D-shaped box;

[0084] A phase detection module, used to detect the phase error between the incident power and the D-box power in real time, and generate an oscillation drive signal when the phases match;

[0085] an amplifying module, used for amplifying the oscillation driving signal;

[0086] The base signal generating module is used to generate a radio frequency base signal according to the received oscillation driving signal to ensure that the frequency and phase of the radio frequency signal accurately match the requirements of the synchrocyclotron accelerator.

[0087] In some embodiments, the main control module includes an FPGA and a central processing unit.

[0088] The working principle and effect of the above technical solution are as follows: the signal of the RF cavity, including the D-box power, and the incident power and reflected power on the directional coupler, is collected in real time through the sampling module, and the sampling signal is fed back to the main control module for subsequent signal processing and feedback adjustment; after receiving the sampling signal, the main control module executes the RF signal control logic; the FPGA and the central processing unit jointly process these signals and analyze the current state of the RF system; according to the analysis results, the main control module generates corresponding feedback adjustment instructions to adjust the frequency and phase of the RF system.

[0089] The phase detection module detects the phase error between the incident power and the D-box power in real time. When the phases match, that is, the phase error between the incident power and the D-box power is within the allowable range, the phase detection module (usually a phase detector) generates an oscillating drive signal; the amplification module (usually an operational amplifier) ​​receives the drive signal and amplifies it to a sufficient power level; the amplified drive signal is used to subsequently generate a radio frequency base signal; the base signal generation module (usually including a voltage-controlled oscillator) generates a radio frequency base signal based on the received amplified drive signal; the radio frequency base signal is used to confirm that the current state is stable and the acceleration process can continue to ensure that the radio frequency signal matches the requirements of the synchrocyclotron accelerator.

[0090] Through the collaborative work of the sampling module, main control module, phase detection module, amplification module and base signal generation module, a closed-loop control system is formed to monitor the status of the RF system in real time and make adjustments as needed to ensure the stability and accuracy of the RF signal.

[0091] FPGA is responsible for implementing complex control logic and algorithms. FPGA can process sampling signals at high speed and generate feedback adjustment instructions in real time. The central processing unit is responsible for the overall management and coordination of the system. The central processing unit processes the feedback adjustment instructions from the FPGA and communicates with other modules to ensure the stable operation of the system.

[0092] In summary, the RF signal control device provided in the embodiment of the present invention realizes closed-loop control of the synchrocyclotron RF signal through the coordinated work of the sampling module, the main control module, the phase detection module, the amplification module and the base signal generating module; the device can monitor the status of the RF system in real time and make adjustments as needed to ensure the stability and accuracy of the RF signal.

[0093] In some embodiments, the driving signal of the phase detection module is directly amplified by the signal amplification module, and then drives the base signal generation module to generate a radio frequency base signal.

[0094] In some other embodiments, the device further comprises an analog-to-digital conversion module and a digital-to-analog conversion module; the analog-to-digital conversion module is used to perform analog-to-digital conversion on the oscillation drive signal; the digital-to-analog conversion module is used to convert the digital signal into an analog signal;

[0095] The driving signal of the phase detection module is converted into a digital signal by the analog-to-digital conversion module and then enters the main control module. After being processed by the main control module, it is converted into digital and amplified, and finally drives the base signal generation module to generate a radio frequency base signal.

[0096] The working principle and effect of the above technical solution are:

[0097] The driving signal generated by the phase detector can drive the base signal generating module to generate a RF base signal through a pure analog link, that is, the driving signal is directly amplified by the signal amplification module to enhance the power and stability of the signal, and the amplified driving signal drives the base signal generating module to generate a RF base signal with a specific frequency and amplitude; the RF base signal is output to subsequent circuits or devices; the driving signal is directly amplified by the amplification module and then drives the base signal generating module to obtain the RF base signal. Since the driving signal is directly amplified, the time delay of digital signal processing is eliminated, so that the response speed of the entire system is faster, and the RF base signal can be adjusted more quickly according to the phase error.

[0098] The driving signal generated by the phase detector can also be driven to generate a radio frequency base signal in a digital manner; that is, the driving signal generated by the phase detector is converted into a digital signal through an analog-to-digital conversion module, which converts the analog signal into a digital signal; this helps to realize the digital processing of the signal and improve the accuracy and stability of the signal. After the digital signal enters the main control module, it is further processed and analyzed. The main control module filters, adjusts or optimizes the digital signal according to a preset algorithm or logic to meet specific application requirements; after being processed by the main control module, in order to convert the processed signal back into an analog form so that the subsequent circuit or device can recognize and process it, the digital signal is converted into a digital-to-analog form through a digital-to-analog conversion module. The analog signal is converted into an analog signal, and the converted analog signal is amplified by a signal amplification module. The amplified analog signal drives a base signal generation module to generate a radio frequency base signal with a specific frequency and amplitude; the radio frequency base signal is output to subsequent circuits or devices; the drive signal is converted into a digital signal by an analog-to-digital conversion module and then enters the main control module, and is processed by the main control chip and then subjected to digital-to-analog conversion and amplification, and finally drives the base signal generation module to generate a radio frequency base signal; the high-precision processing capability of the main control module can be used to fine-tune the signal, thereby improving the accuracy and stability of the radio frequency base signal; digital signals are easy to store, transmit and process, and can be more flexibly adapted to different application scenarios and needs.

[0099] In some embodiments, the device further comprises a calibration module, the calibration module being used to calibrate the frequency points of the RF scanning cycle through the RF power signal;

[0100] The radio frequency power signal includes radio frequency on, radio frequency off and ion source on; the calibration module controls the radio frequency power on time interval and the ion source on time in each scanning cycle.

[0101] The working principle and effect of the above technical solution are as follows: RF power signals mainly include three types: RF On, RF Off and Ion On; these signals are generated by the main control chip FPGA in the RF signal control device according to the preset logic and algorithm, and transmitted to the calibration module through the corresponding circuit; the calibration module receives the RF power signal from the RF signal control system; according to the type of signal (RF On, RF Off or Ion On), the calibration module determines the corresponding frequency point within the RF scanning cycle; within each RF scanning cycle, the calibration module accurately controls the RF power on time interval and the ion source on time according to the preset logic and algorithm; it ensures that the RF power and the ion source on time can match the system's operating requirements and beam characteristics, thereby achieving optimized control; the sampling module in the RF signal control system will collect the RF cavity signal (such as D-box power), incident power and reflected power) and the output signal of the calibration module in real time. The sampling signal is fed back to the main control chip FPGA for real-time monitoring of the system's operating status and beam characteristics. According to the feedback signal, the main control chip can adjust the RF power and the on-time of the ion source in real time to further optimize the beam characteristics and the stability of the system; through the calibration module's precise control of the RF power and the on-time of the ion source in each scanning cycle, the system can flexibly adjust the beam characteristics in each cycle, which helps to achieve stable acceleration and precise control of the proton beam, thereby improving the accuracy and effectiveness of medical accelerator proton radiotherapy.

[0102] In some embodiments, the device also includes an amplitude modulation module (AM table modulation) for adjusting the gain of the RF base signal; the amplitude modulation module includes a step attenuator and a digitally adjustable gain device, the RF base signal is attenuated by the step attenuator, and the attenuated signal is amplified again by the digitally adjustable gain device.

[0103] In some embodiments, the amplitude modulation module further includes a time slice division unit, which is used to divide the power amplification time interval into a plurality of time slices and control the loaded gain signal in each time slice.

[0104] In some embodiments, the device further comprises a remote interaction module, through which the amplitude gain of the digital adjustable gain device is controlled.

[0105] The working principle and effect of the above technical solution are as follows: on the basis of generating the RF base signal, the next step is how to modulate the amplitude of the signal to a range that can be accepted by the post-stage amplifier. In the present invention, the signal gain can be adjusted with maximum range and high precision by combining digital and analog methods. First, the signal of the voltage-controlled oscillator (RF base signal) is attenuated using a step attenuator, and the amplitude strength of the base signal can be dynamically adjusted. After passing through the step attenuator, the signal is amplified again using a digital adjustable gain device. The purpose of adding this module is to enable the control system to develop a user interaction interface to remotely control the amplitude gain. The time slice division unit divides the power amplification time interval into multiple time slices, and controls the gain signal loaded into the time slice in each time slice. The control range depends on the linear gain range of the gain device, and the control accuracy depends on the number of digits of the high-speed digital-to-analog converter; the step attenuator and the digital adjustable gain device work together to accurately control the loaded gain signal; the RF signal after amplitude modulation is output for subsequent processing or transmission.

[0106] In some embodiments, the device further comprises a fixed attenuator and / or a hardware safety interlock module, wherein the fixed attenuator is used to limit the maximum output amplitude of the radio frequency signal;

[0107] The hardware safety interlocking module determines whether the modulated radio frequency signal meets the preset conditions. If so, the modulated radio frequency signal is sent to the radio frequency amplifier; if not, the radio frequency signal is safely cut off.

[0108] The working principle and effect of the above technical solution are as follows: a fixed attenuator is an electronic device used to reduce signal strength. It effectively controls signal power by introducing a specific attenuation amount in the signal path. In the RF system, the fixed attenuator is used to limit the maximum output amplitude of the RF signal to prevent the signal from being too strong and causing damage or interference to the system. Specifically, the fixed attenuator uses a fixed resistor element or attenuation network inside. When the RF signal passes through, these elements will disperse the signal energy into heat energy and other forms for attenuation, thereby reducing the signal power. By limiting the maximum output amplitude of the RF signal, the fixed attenuator can protect other components in the system (such as the RF amplifier) ​​from being damaged by strong signals.

[0109] The hardware safety interlock module is a safety protection mechanism that complies with the safety interlock design requirements of medical regulations; the module includes a signal detection unit, a judgment logic unit, and an execution unit.

[0110] The signal detection unit is used to detect the modulated RF signal and extract its key parameters (such as frequency, power, etc.).

[0111] The judgment logic unit is used to judge the detected signal parameters according to preset conditions (such as signal frequency range, power threshold, etc.).

[0112] The execution unit is used to send a control signal to the RF amplifier to allow it to amplify the RF signal when the judgment result is "the preset conditions are met"; when the judgment result is "the preset conditions are not met", the RF signal is prevented from entering the amplifier, or safety measures such as alarms are triggered.

[0113] Through the judgment of the hardware safety interlock module, it can be ensured that only RF signals that meet the preset conditions can enter the RF amplifier for amplification, preventing unqualified signals from damaging the system; protecting RF system components from high power damage.

[0114] Refer to the attached Figure 2 The embodiment of the present invention provides a radio frequency system, the radio frequency system is used to realize ion acceleration control of a synchrocyclotron accelerator, and the system includes:

[0115] The RF power amplifier is used to amplify the input low-amplitude RF signal by a fixed gain multiple and then output it to the RF cavity; ensuring that the output signal has sufficient power to meet the acceleration requirements; the RF cavity is used for RF signal transmission and energy conversion of proton bunches;

[0116] Any of the RF signal control devices described in the embodiments of the present invention is used to obtain a sampling signal, provide real-time feedback of a power value and a phase error, and generate a driving signal based on the power value and the phase error to control the operation of the RF power amplification device and the RF cavity, thereby achieving closed-loop control of the RF signal.

[0117] In some embodiments, the RF cavity adopts a three-quarter wavelength cavity design, the RF signal varies in the range of 85 MHz to 133.5 MHz, can withstand a power of 20 kW, and can pull out a relatively static proton beam under a specific magnetic field and accelerate it to 230 MeV for use in medical accelerator proton radiotherapy.

[0118] Refer to the attached Figure 3 The RF power amplifier is a high-power device that amplifies the input low-amplitude RF signal by a fixed gain multiple and outputs it into the cavity. It has good dynamic response capability and continuous and stable output capability.

[0119] The working principle of the above technical solution is:

[0120] The RF power amplifier is a high-power device with good dynamic response capability and continuous and stable output capability. The RF power amplifier amplifies the input low-amplitude RF signal to a fixed gain multiple and then outputs it to the RF cavity; because the amplified RF signal needs to have sufficient power to meet the energy requirements of proton beam acceleration.

[0121] As the transmission medium of radio frequency signals and the place for proton bunch energy conversion, the radio frequency cavity plays a key role in the ion acceleration process. The radio frequency cavity in the embodiment of the present invention adopts a three-quarter wavelength cavity design, which can cover the center frequency range and adapt to most wavelength frequencies; the range of variation of the parameter radio frequency signal is set to 85MHz to 133.5MHz, and can withstand power up to 20KW. Under specific magnetic field conditions, the radio frequency cavity can pull out relatively static proton bunches and accelerate them to an energy level of 230MeV, which helps to optimize the transmission efficiency of radio frequency signals and the energy conversion efficiency of proton bunches; it is suitable for medical accelerator proton radiotherapy applications.

[0122] As the control core of the RF system, the RF signal control device is responsible for acquiring the sampling signal, providing real-time feedback of the power value and phase error, and generating a driving signal based on this information to control the operation of the RF power amplifier and the RF cavity.

[0123] The specific workflow is:

[0124] The sampling module collects the signals of the RF cavity (such as the D-box power) and the incident power and reflected power on the directional coupler in real time, and feeds these sampling signals back to the main control module. The main control module processes the sampling signals and analyzes the current state of the RF system. The phase detection module detects the phase error between the incident power and the D-box power in real time, and generates an oscillating drive signal when the phase matches; the amplification module receives and amplifies the drive signal, and then sends it to the base signal generation module. The base signal generation module generates an RF base signal based on the amplified drive signal to adjust the frequency and phase of the RF system to ensure that they match the motion state of the proton beam.

[0125] The closed-loop control RF signal control device forms a closed-loop control system through real-time sampling, signal processing, phase detection, signal amplification and background signal generation. It can continuously adjust the frequency and phase of the RF signal to cope with various changes that may occur during the proton acceleration process, thereby achieving stable ion acceleration control.

[0126] In the synchrocyclotron, the radio frequency system achieves precise control of ion acceleration through the above working principle; the specific process is as follows:

[0127] The proton bunch is pulled into the radio frequency cavity under specific magnetic field conditions;

[0128] The RF power amplifier amplifies the low-amplitude RF signal to a sufficient power and then outputs it into the RF cavity;

[0129] The radio frequency signal in the radio frequency cavity interacts with the proton bunch, transferring energy to the proton bunch and accelerating it;

[0130] The RF signal control device monitors the signal and power status in the RF cavity in real time, as well as the phase error between the incident power and the D-box power. Based on the monitoring results, the RF signal control device generates a corresponding drive signal and adjusts the operating parameters of the RF power amplifier and the RF cavity to ensure that the frequency and phase of the RF signal match the motion state of the proton bunch. By continuously adjusting and optimizing the frequency and phase of the RF signal, the RF system achieves stable acceleration control of the proton bunch, ultimately accelerating it to the desired energy level (such as 230MeV).

[0131] An embodiment of the present invention provides a particle radiation therapy system, comprising:

[0132] an ion source for generating an ion beam;

[0133] The radio frequency system described in the embodiment of the present invention is used to provide a radio frequency signal to generate an accelerating electric field for accelerating an ion beam to a required energy level.

[0134] The radio frequency system generates a high-frequency alternating electromagnetic field to form an accelerating electric field inside the particle accelerator. When charged particles (such as ions) pass through this electric field, they are affected by the electric field force, thereby gaining energy acceleration; by adjusting the frequency, amplitude, and phase of the radio frequency signal, the intensity and distribution of the accelerating electric field can be precisely controlled, thereby achieving precise regulation of the charged particle acceleration process.

[0135] See attached Figure 4 The embodiment of the present invention provides a radio frequency signal control method for realizing closed-loop control of the radio frequency signal of a synchrocyclotron accelerator. The method is realized by any radio frequency signal control device described in the embodiment of the present invention, and includes:

[0136] Real-time acquisition of the signal of the radio frequency cavity and the incident power and the reflected power on the directional coupler, wherein the signal of the radio frequency cavity includes the D-box power;

[0137] detecting the phase error between the incident power and the D-box power in real time, and generating an oscillating driving signal when the phases match;

[0138] The base signal generating module is driven by the driving signal to obtain a radio frequency base signal.

[0139] The working principle of the above technical solution is: the signal of the RF cavity, including the D-box power, and the incident power and reflected power on the directional coupler, is collected in real time through the sampling module, and the sampling signal is fed back to the main control module for subsequent signal processing and feedback adjustment; after receiving the sampling signal, the main control module executes the RF signal control logic; the FPGA and the central processing unit jointly process these signals and analyze the current state of the RF system; according to the analysis results, the main control module generates corresponding feedback adjustment instructions to adjust the frequency and phase of the RF system.

[0140] The phase detection module detects the phase error between the incident power and the D-box power in real time. When the phases match, that is, the phase error between the incident power and the D-box power is within the allowable range, the phase detection module generates an oscillating drive signal; the amplification module (usually an operational amplifier) ​​receives the drive signal and amplifies it to a sufficient power level; the amplified drive signal is used to subsequently generate a radio frequency base signal; the base signal generation module (including a voltage-controlled oscillator) generates a radio frequency base signal based on the received amplified drive signal; the radio frequency base signal is used to confirm that the current state is stable and the acceleration process can continue to ensure that the radio frequency signal matches the requirements of the synchrocyclotron accelerator.

[0141] Through the collaborative work of the sampling module, main control module, phase detection module, amplification module and base signal generation module, a closed-loop control system is formed to monitor the status of the RF system in real time and make adjustments as needed to ensure the stability and accuracy of the RF signal.

[0142] In some embodiments, the RF signal control method includes: if the phase does not match, that is, the phase error between the incident power and the D-box power exceeds the allowable range, the frequency and phase of the RF base signal are automatically adjusted by the main control module according to the error size and direction; if the phase still does not match after a preset time or adjustment times, an early warning is triggered;

[0143] Among them, the frequency and phase of the RF base signal are automatically adjusted through the main control module according to the error size and direction; including, if the phase error exceeds the preset adjustment amount, first adjust according to the preset adjustment amount; and detect the limit error again after the system is stable;

[0144] The time interval between two consecutive adjustments must meet the following conditions:

[0145] T interval ≥(1±α)*(Tr+Ts)+Tb

[0146] Tb=max(Tr,Ts) / m

[0147] Among them, T intervalis the time interval between two adjacent adjustments, α is the adjustment coefficient, 0<α<0.5, Tr is the system response time, Ts is the system stabilization time, Tb is the time safety margin, m is a constant, 1 <m<5。

[0148] The working principle of the above technical solution is:

[0149] First, the phase error between the incident power and the D-box power is detected;

[0150] If the phase error exceeds the allowable range, the adjustment process begins.

[0151] If the phase error exceeds the preset adjustment amount, the frequency and phase of the RF base signal are first adjusted according to the preset adjustment amount; the preset adjustment amount is pre-set based on system characteristics and requirements to ensure that the adjustment process is neither too aggressive nor too conservative.

[0152] After the adjustment is completed, we will wait for a while to ensure that the system can stabilize in the new state.

[0153] After stabilization, the phase error is monitored again to assess the effectiveness of the adjustments.

[0154] If the phase error has been reduced to within the allowable range, the adjustment process ends.

[0155] If the phase error still exceeds the allowable range, the next adjustment process will be entered.

[0156] There is a certain time interval between two consecutive adjustments.

[0157] If the phase still does not match after the preset time or number of adjustments, an early warning will be triggered.

[0158] The effects of the above technical solution are: by real-time monitoring of the phase error between the incident power and the D-box power, and automatically adjusting the frequency and phase of the RF base signal when the error exceeds the allowable range, it can quickly respond to the problem of phase mismatch, thereby maintaining the stable operation of the system; when the phase error exceeds the preset adjustment amount, it is first adjusted according to the preset adjustment amount, which not only avoids the system instability caused by overly aggressive adjustment, but also ensures the effectiveness of the adjustment. At the same time, the limit error is monitored again after the system is stable, further improving the accuracy of the adjustment; by controlling the time interval between two adjacent adjustments, the potential damage to the system hardware caused by frequent adjustments is avoided; the calculation of the time interval takes into account the system response time and stabilization time, and introduces a time safety margin to ensure that the system has enough time to adapt and adjust, thereby extending the service life of the hardware; through reasonable adjustment strategies and time interval control, the system can reach a phase matching state in a shorter time, thereby improving the overall work efficiency; if the phase is still mismatched after the preset time or number of adjustments, the system triggers an early warning mechanism, which can not only promptly remind the operator to pay attention to the abnormal situation of the system, but also provide a valuable time window for subsequent fault diagnosis and repair, thereby enhancing the reliability of the system.

[0159] In some embodiments, driving the base signal generating module with the driving signal to obtain the radio frequency base signal includes:

[0160] The driving signal is directly amplified and then driven to drive the base signal generating module to obtain a radio frequency base signal. The driving signal is directly amplified by the amplification module and then driven to drive the base signal generating module to obtain a radio frequency base signal.

[0161] In some embodiments, the step of driving a base signal generating module with the driving signal to obtain a radio frequency base signal comprises:

[0162] The driving signal is converted into a digital signal through the analog-to-digital conversion module and then enters the main control module, and is processed by the main control chip and then subjected to digital-to-analog conversion and amplification, and finally drives the base signal generation module to generate a radio frequency base signal; that is, the driving signal of the phase detection module is converted into a digital signal through the analog-to-digital conversion module and then enters the main control module, and is processed by the main control module and then subjected to digital-to-analog conversion and amplification, and finally drives the base signal generation module to generate a radio frequency base signal.

[0163] In some embodiments, the radio frequency signal control method further includes:

[0164] The frequency point of the radio frequency scanning cycle is calibrated by the radio frequency power signal; the radio frequency power signal includes turning on the radio frequency, turning off the radio frequency and turning on the ion source;

[0165] The frequency points of the RF scanning cycle are calibrated by the RF power signal; including:

[0166] Set the scanning range and scanning step to scan the frequency of the RF signal;

[0167] Monitor the incident power on the directional coupler in real time; record the incident power value corresponding to each frequency point;

[0168] The incident power peak or stable area is obtained by the incident power value at each frequency point;

[0169] When the incident power reaches a preset threshold or stabilizes within a preset range, the calibration condition is triggered;

[0170] The scanning range and scanning step are set to scan the frequency of the RF signal; including:

[0171] Obtain the initial scanning range through historical data;

[0172] Real-time monitoring of the system's ion source system status information, including the accelerator's load and temperature; dynamically adjust the scanning range based on the system status information;

[0173] Set the initial scan step size; set a relatively large initial step size to quickly traverse the scan range;

[0174] According to the scanned frequency point data, the step size of subsequent scans is dynamically adjusted; if multiple valid matching points are found in a certain frequency interval, the step size is reduced to increase the scanning accuracy; the iterative optimization method gradually approaches the optimal frequency point through multiple scans and step size adjustments.

[0175] The working principle and effect of the above technical solution are: to accurately calibrate the frequency points of the RF scanning cycle through the RF power signal, especially in scenarios involving complex RF power signals such as turning on the RF, turning off the RF and turning on the ion source.

[0176] First, the system determines an initial scanning range based on historical data. This range usually covers the area that may contain the optimal frequency point. The system monitors the status information of the ion source system in real time, including the load and temperature of the accelerator, and dynamically adjusts the scanning range based on this status information to ensure that the scanning process can cover the area that is most likely to contain the optimal frequency point.

[0177] After determining the scanning range, set a relatively large initial step size to quickly traverse the entire scanning range; the purpose of this step is to quickly find the frequency interval that may contain valid matching points. As the scan progresses, record the incident power value corresponding to each frequency point, and determine the peak or stable area of ​​the incident power by analyzing these data.

[0178] When multiple valid matching points are found within a certain frequency range, an iterative optimization method is used to gradually approach the optimal frequency point. Specifically, the system will reduce the step size to increase the scanning accuracy and rescan the frequency range at each smaller step size. Through multiple scans and adjustment of the step size, the search range can be gradually narrowed and a more accurate optimal frequency point can be found.

[0179] During the whole process, the incident power on the directional coupler is monitored in real time to ensure the accuracy and integrity of the data. When the incident power reaches the preset threshold or stabilizes within the preset range, the calibration condition is triggered;

[0180] In summary, accurate calibration of the frequency points of the RF scanning cycle is achieved through strategies such as dynamic adjustment of the scanning range and step size, real-time monitoring and analysis of incident power data, and iterative optimization.

[0181] In some embodiments, the radio frequency signal control method further includes:

[0182] The gain of the radio frequency base signal is adjusted by an amplitude modulation module, wherein the amplitude modulation module includes a step attenuator and a digital adjustable gain device, the radio frequency base signal is attenuated by the step attenuator, and the attenuated signal is amplified again by the digital adjustable gain device;

[0183] The power amplification time interval is divided into multiple time slices, and the loaded gain signal is controlled in each time slice;

[0184] The amplitude gain of the digital adjustable gain amplifier is controlled by the remote interaction module.

[0185] In some embodiments, the step of dividing the power amplification time interval into a plurality of time slices and controlling the loaded gain signal in each time slice comprises:

[0186] According to the clock frequency, the power amplification time interval is evenly divided into multiple time slices, and the number of divisions is 2 to the power of n, where n is a positive integer; according to the preset gain strategy or algorithm, the gain value to be loaded in each time slice is determined; the gain value can be achieved by a digital adjustable gain device (such as VGA, variable gain amplifier). Among them, the preset gain strategy or algorithm, such as the automatic gain control (AGC) algorithm, adjusts the gain value in real time by monitoring the peak value, average power and other characteristics of the input signal, or finds the corresponding gain value on the gain curve according to the characteristics of the real-time RF signal (such as strength, frequency, etc.).

[0187] The working principle and effect of the above technical solution are as follows: the RF base signal first passes through a step attenuator to accurately attenuate the signal as needed. The attenuated signal is then amplified by a digital adjustable gain device (such as a VGA). The VGA can adjust its gain value according to the control signal, thereby achieving precise control of the RF signal amplitude.

[0188] The power amplification time interval is evenly divided into multiple time slices according to the clock frequency, and the number of divisions is 2 to the power of n (n is a positive integer); this helps to simplify time management and signal processing, while ensuring that the signal characteristics within each time slice are relatively stable.

[0189] In each time slice, the gain value to be loaded is determined according to a preset gain strategy or algorithm (such as an automatic gain control algorithm); the automatic gain control algorithm adjusts the gain value in real time by monitoring the peak value, average power and other characteristics of the input signal to maintain the stability of the output signal; it can also find the corresponding gain value on the preset gain curve according to the characteristics of the real-time RF signal (such as strength, frequency, etc.).

[0190] Through the remote interaction module, users can conveniently control the amplitude gain of the digital adjustable gain amplifier, which provides additional flexibility and allows users to adjust the gain setting of the system according to actual needs.

[0191] Through precise amplitude modulation and time slice division, the system can more accurately control the gain value of the RF signal, thereby optimizing the signal quality. This helps reduce signal distortion and noise interference and improves system performance.

[0192] The automatic gain control algorithm can monitor the characteristics of the input signal in real time and adjust the gain value as needed, which helps to maintain the stability of the output signal and reduce system instability caused by signal fluctuations.

[0193] In some embodiments, the step of dividing the power amplification time interval into a plurality of time slices and controlling the loaded gain signal in each time slice comprises:

[0194] Real-time monitoring of RF signals, including signal strength, frequency and phase characteristics;

[0195] Conduct data analysis on the monitored signals and identify the changing trends of the signals;

[0196] Dynamically divide time slices according to the changing trend of the RF signal; in areas where the signal changes faster, divide the time slices into shorter ones to capture the details of the signal changes; in areas where the signal changes slower, divide the time slices into longer ones to reduce the amount of calculation;

[0197] Calculate the gain value to be loaded in the time slice according to the real-time monitored RF signal characteristics and the preset gain strategy;

[0198] The calculated gain value is loaded onto the digital adjustable gain device to achieve gain control of the RF signal.

[0199] The working principle and effect of the above technical solution are:

[0200] Monitor the strength, frequency and phase characteristics of RF signals in real time.

[0201] Perform data analysis on the monitored signals to identify the changing trends of the signals, including fluctuations in signal amplitude, frequency drift, and phase stability. Dynamically divide time slices according to the changing trends of the signals. In areas where the signals change rapidly, the system divides shorter time slices to capture the details of the signal changes. In areas where the signals change slowly, the system divides longer time slices to reduce the amount of calculation and improve processing efficiency. Specifically:

[0202] Set an initial time slice length.

[0203] Set a signal change rate threshold ΔV_threshold to determine whether the signal changes rapidly;

[0204] Set a time slice length adjustment scale factor scale_factor to adjust the time slice length;

[0205] At the end of each time slice, the current value Vc of the RF signal and the signal value Vp of the previous time slice are monitored;

[0206] Calculate the signal change ΔV = |Vc-Vps|;

[0207] If ΔV>ΔVthreshold, the signal is considered to be changing rapidly;

[0208] If ΔV<=ΔVthreshold, the signal is considered to change slowly or remain stable;

[0209] If the signal is changing rapidly, the time slice length is adjusted to Tnew=Tc / scale_factor, where Tc is the current time slice length and scale_factor is a positive number greater than 1, indicating that the time slice length is shortened.

[0210] If the signal changes slowly or remains stable, the time slice length is adjusted to Tnew=Tc*scale_factor, where scale_factor is a positive number greater than 1, indicating that the time slice length is extended.

[0211] At the same time, in order to avoid the time slice length being too short or too long, the minimum and maximum values ​​of the time slice length are set.

[0212] At the beginning of the next time slice, the new time slice length Tnew is used for division.

[0213] Repeat the above steps until the RF signal control process is completed.

[0214] In each time slice, the gain value to be loaded in the time slice is calculated based on the real-time monitored RF signal characteristics and the preset gain strategy (such as automatic gain control algorithm or gain curve); then, the calculated gain value is loaded onto a digital adjustable gain device (such as VGA) to achieve gain control of the RF signal.

[0215] By dynamically dividing time slices, the changing details of the RF signal can be captured more accurately, thereby improving the accuracy of signal processing; it helps to reduce signal distortion and noise interference and improve system performance; in areas where the signal changes slowly, the amount of calculation is reduced by dividing the time slices into longer time slices, thereby optimizing resource utilization and reducing system power consumption and cost.

[0216] In some embodiments, the radio frequency signal control method further includes:

[0217] Limiting the maximum output amplitude of the RF signal by a fixed attenuator;

[0218] It is determined whether the modulated RF signal meets a preset condition. If so, the modulated RF signal is sent to the RF amplifier.

[0219] See attached Figure 5 and attached Figure 6 Some embodiments of the present invention provide an ion source automatic beam adjustment method, which is applicable to a particle radiation therapy system, especially a particle radiation therapy system according to an embodiment of the present invention, and the method comprises:

[0220] Setting initialization parameters, including frequency parameters of a radio frequency power signal, so that the accelerator can operate stably; wherein the radio frequency power signal includes turning on the radio frequency, turning off the radio frequency, and turning on the ion source;

[0221] Monitor and adjust multiple control parameters in real time to obtain an optimal control parameter combination; the control parameters include the frequency of triggering proton beam generation (Trigger frequency), DC bias voltage (DC Bias DC bias voltage, used to suppress secondary electron emission during proton beam generation), hydrogen flow rate, amplitude modulation value (AM Table), operating frequency of the rotating capacitor motor (RotC) and adaptive coil position (ACP);

[0222] Under the optimal control parameter combination, the change amount of each control parameter before and after adjustment and the performance change of the proton beam are obtained; according to the change amount of each parameter before and after adjustment and the performance change of the proton beam, a pulse width charge (PWC) test is performed;

[0223] The optimal adjustment parameters and adjustment amount are obtained through the test results; automatic beam adjustment is achieved through the optimal adjustment parameters and adjustment amount.

[0224] The working principle of the above technical solution is as follows: before starting the automatic beam adjustment, a series of initialization parameters need to be set first. These parameters include the frequency parameters of multiple RF power signals to ensure that the accelerator can operate stably and avoid frequency conflicts or instability; the RF power signal mainly includes three states: RF on, RF off and ion source on, which correspond to the on and off of the RF system and the on of the ion source respectively. The frequency parameters of RF On, RF Off and Ion On are set on the host computer, and the host computer exchanges information with the RF signal control system through network communication.

[0225] A series of control parameters are monitored and adjusted in real time, including the frequency of triggering proton beam generation, DC bias voltage (used to suppress secondary electron emission during proton beam generation), hydrogen flow rate, amplitude modulation value, operating frequency of the rotary capacitor motor, and adaptive coil position.

[0226] The control parameters are adjusted through a feedback mechanism, that is, the system dynamically adjusts these parameters according to the real-time monitored proton beam performance (such as beam intensity, beam spot size, etc.) to obtain the best proton beam performance, thereby obtaining the optimal control parameter combination;

[0227] Under the optimal control parameter combination, the change amount of each control parameter before and after adjustment is recorded, and the performance change of the proton beam is monitored at the same time, and the performance change includes the stability of the beam intensity, the uniformity of the beam spot size, etc.; based on the change amount of each parameter before and after adjustment and the performance change of the proton beam, a pulse width charge test is further performed; the pulse width charge test is a method for evaluating the performance of the proton beam by changing the pulse width and charge of the proton beam; through the test, the influence of each control parameter on the performance of the proton beam can be understood more accurately.

[0228] According to the results of the pulse width and charge test, the optimal adjustment parameters and adjustment amounts are analyzed and determined, which can make the proton beam performance reach the best state. Finally, according to the optimal adjustment parameters and adjustment amounts, each control parameter is automatically adjusted to realize the automatic beam adjustment of the ion source. At the same time, the proton beam performance is continuously monitored and fine-tuned as needed to ensure the stability and consistency of the proton beam.

[0229] In some embodiments, the real-time monitoring and adjusting of control parameters; obtaining a preferred control parameter combination includes:

[0230] Adjusting the DC bias voltage to suppress secondary electron emission;

[0231] After the DC bias voltage is regulated, the amplitude modulation value is adjusted and the hydrogen flow rate is adjusted synchronously;

[0232] Adjusts the adaptive coil position and operating frequency of the rotary capacitor motor;

[0233] Through various adjustment results, the optimal control parameter combination is obtained.

[0234] The working principle and effect of the above technical solution are:

[0235] First, adjust the DC bias voltage (RF DC Bias) to suppress secondary electron emission. During the ion beam generation process, high-energy ions hitting the material surface may cause secondary electron emission. If these secondary electrons are not controlled, they may affect the stability and purity of the ion beam. By adjusting the DC bias voltage, an electric field can be formed, which can suppress the emission of secondary electrons, thereby maintaining the stability of the ion beam. The host computer interacts with the RF signal control system through network communication and sends instructions to adjust the DC bias voltage. After receiving the instructions, the RF signal control system adjusts the corresponding circuit parameters to achieve the change of the DC bias voltage.

[0236] The amplitude modulation value determines the intensity change mode of the RF signal. By adjusting the amplitude modulation value, the generation efficiency and energy distribution of the ion beam can be changed. At the same time, the hydrogen flow rate is the raw material for generating protons, and its size directly affects the intensity and stability of the ion beam. Therefore, synchronously adjusting these two parameters can further optimize the performance of the ion beam.

[0237] After completing the DC bias voltage adjustment, the host computer continues to send instructions to adjust the amplitude modulation value, and the RF signal control system adjusts the parameters of the amplitude modulation circuit according to the instructions. At the same time, by controlling the valve opening of the hydrogen supply system, the hydrogen flow rate is adjusted synchronously. The adjustment of these two parameters is interdependent, and it is necessary to find the optimal combination through iterative adjustment.

[0238] Adaptive coil position adjustment is a fine-tuning method. By changing the relative position of the superconducting magnet coil bracket, the intensity distribution of the magnetic field can be indirectly corrected, which helps to optimize the trajectory and focusing performance of the ion beam.

[0239] After the amplitude modulation value and hydrogen flow rate are adjusted to a certain extent, the host computer sends a command to adjust the position of the adaptive coil; after receiving the command, the RF signal control system or the special mechanical control system drives the corresponding actuator (such as a stepper motor) to change the position of the coil bracket. The operating frequency of the rotary capacitor motor affects the phase and frequency stability of the RF signal. By adjusting its operating frequency, the performance and stability of the ion beam can be further optimized.

[0240] After the adaptive coil position is adjusted, the host computer sends a command to adjust the operating frequency of the rotary capacitor motor. After receiving the command, the RF signal control system or the motor control system adjusts the operating frequency of the motor.

[0241] The adjustment of all the above parameters is interrelated, and it is necessary to find the optimal combination through iterative adjustment. After each parameter adjustment, the RF signal control system will monitor the values ​​of relevant parameters (such as beam intensity, beam spot size, etc.) in real time, and feed these values ​​back to the host computer; the host computer automatically calibrates and dynamically adjusts according to the feedback results, and records the parameter changes before and after the adjustment and the adjustment results of each parameter in real time.

[0242] After multiple iterations of adjustments, the host computer will determine the optimal control parameter combination based on the monitoring results.

[0243] In some embodiments, the real-time monitoring and adjusting of control parameters; obtaining a preferred control parameter combination includes:

[0244] Through historical data, the influence curve of each control parameter on each beam characteristic is obtained;

[0245] According to the influence curve of each control parameter on each beam characteristic, a first adjustment range of each control parameter is set;

[0246] Within the first adjustment range, a plurality of continuous control points are set for each control parameter;

[0247] By continuously controlling the points and adjusting the control parameters, the changing trend of the beam characteristics can be obtained;

[0248] Obtaining a second adjustment range of each control parameter through a real-time beam characteristic change trend;

[0249] Within the second adjustment range, adjust each control point of each control parameter one by one;

[0250] Monitor the values ​​of each control parameter before and after adjustment in real time, determine the parameters that significantly affect the beam properties by comparing the beam characteristics under different parameter combinations, and make further iterative adjustments to the parameters that significantly affect the beam properties;

[0251] The optimal control parameter combination is obtained through iterative adjustment.

[0252] The working principle of the above technical solution is: using historical data, analyzing and drawing the influence curve of each control parameter (such as trigger frequency, DC bias voltage, hydrogen flow rate, amplitude modulation value, rotating capacitor motor frequency, adaptive coil position) on beam characteristics (such as flow intensity, stability, etc.); based on the influence curve, setting the first adjustment range of each control parameter, the first adjustment range covers the reasonable range of the parameter, so as to facilitate preliminary adjustment and observation.

[0253] In the first adjustment range of each control parameter, multiple continuous control points are set to gradually adjust and obtain the beam characteristics; through continuous control points, each control parameter (such as DC bias voltage, amplitude modulation value, hydrogen flow, adaptive coil position, rotating capacitor motor operating frequency, etc.) is gradually adjusted; in this process, the change trend of beam characteristics (such as beam intensity, beam spot size, beam stability, etc.) is monitored in real time;

[0254] According to the variation trend of the beam characteristics, a second adjustment range of each control parameter is determined, wherein the second adjustment range is usually narrower than the first adjustment range and closer to the optimal value;

[0255] In the second adjustment range, the control point of each control parameter is adjusted accurately one by one, and the adjustment is further refined; each time a parameter is adjusted, other parameters are kept unchanged so as to accurately obtain the influence of the parameter on the beam characteristics; by adjusting one by one, the influence of each control parameter on the beam characteristics is further refined, and the parameters that have a significant influence on the beam performance are determined; in the process of adjusting each control parameter, the values ​​of the relevant control parameters before and after adjustment are monitored in real time, and the changes in the beam characteristics are recorded; by comparing the beam characteristics under different parameter combinations, the optimal control parameter combination is obtained by iteratively adjusting the significantly affecting parameters; iterative adjustments are made for the determined significantly affecting parameters. Each time a parameter is adjusted, other parameters are kept unchanged, and the changes in the beam characteristics are observed and recorded. According to the adjustment results, the optimal control parameter combination is gradually approached; in the iterative adjustment process, a variety of optimization strategies can be used, such as gradient descent method, genetic algorithm, particle swarm optimization, etc., to accelerate the finding of the optimal control parameter combination; the results of multiple iterative adjustments are comprehensively analyzed to determine the optimal parameter combination to achieve the best performance of the beam.

[0256] The effects of the above technical solution are as follows: by analyzing historical data in detail and understanding the specific influence of each control parameter on beam characteristics, the initial adjustment range (first adjustment range) can be set more accurately, thereby reducing the adjustment time and improving the efficiency of parameter adjustment; multiple continuous control points are set within the first adjustment range, and the changing trend of beam characteristics is monitored in real time, making the adjustment process more detailed and systematic, which helps to capture the significant influence of small changes in parameters on beam characteristics, so that the second adjustment range can be determined more accurately and the adjustment strategy can be further optimized; by real-time monitoring of the numerical changes of relevant control parameters before and after adjustment, and comparing the beam characteristics under different parameter combinations, the parameters that have a significant influence on beam performance (significantly influencing parameters) can be quickly identified, and further iterative adjustment of the significantly influencing parameters can help gradually approach the optimal parameter combination; not only the accuracy of parameter adjustment is improved, but also it is ensured that the final preferred control parameter combination can maximize the improvement of beam performance.

[0257] Through scientific methods and systematic adjustment processes, the optimal control parameter combination obtained not only performs well under the current conditions, but is also more likely to maintain stable beam performance at different times, with different equipment or under different operating conditions, thereby enhancing the repeatability of the experiment and the reliability of the results, and improving the efficiency and accuracy of beam performance adjustment.

[0258] An embodiment of the present invention further provides an electronic device, comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of any one of the methods described in the embodiments of the present invention or the functions of the device described in the embodiments of the present invention are implemented.

[0259] An embodiment of the present invention further provides a computer-readable storage medium, which is used to store a computer program. When the computer program is executed, the steps of the method in the embodiment of the present invention are implemented. The specific implementation method is consistent with the implementation method and the technical effect achieved recorded in the above method embodiment, and some contents will not be repeated here.

[0260] In the present invention, a readable storage medium may be any tangible medium containing or storing a program that may be used by or in combination with an instruction execution system, device, or device. A program product may employ any combination of one or more readable media. A readable medium may be a readable signal medium or a readable storage medium. A readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or device, or any combination of the above. More specific examples (a non-exhaustive list) of readable storage media include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0261] Computer-readable storage media may include data signals propagated in baseband or as part of a carrier wave, wherein readable program codes are carried. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. The readable storage medium may also be any readable medium, which may send, propagate, or transmit a program for use by an instruction execution system, an apparatus, or a device or for use in combination with it. The program code contained on the readable storage medium may be transmitted by any suitable medium, including but not limited to wireless, wired, optical cable, RF, etc., or any suitable combination of the above. The program code for performing the operation of the present invention may be written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Java, C++, etc., and also conventional procedural programming languages ​​such as C language or similar programming languages. The program code may be executed entirely on a user computing device, partially on an associated device, as an independent software package, partially on a user computing device, partially on a remote computing device, or entirely on a remote computing device or server. Where a remote computing device is involved, the remote computing device may be connected to the user computing device through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computing device (e.g., through the Internet using an Internet service provider).

[0262] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, substitute and modify the above embodiments within the scope of the invention without departing from the principles and purpose of the present invention. All such changes should fall within the scope of protection of the claims of the present invention.

Claims

1. A radio frequency signal control device for realizing closed-loop control of radio frequency signals of a synchrocyclotron accelerator, characterized in that: The device comprises: A radio frequency signal control device, used to implement closed-loop control of radio frequency signals of a synchrocyclotron accelerator, characterized in that: The device comprises: The main control module is used for executing the RF signal control logic, including receiving sampling signals, signal processing and feedback adjustment; A sampling module is used to collect the signal of the radio frequency cavity and the incident power and reflected power on the directional coupler in real time and feed them back to the main control module. The signal of the radio frequency cavity includes the D-box power. A phase detection module, used to detect the phase error between the incident power and the D-box power in real time, and generate an oscillation drive signal when the phases match; an amplifying module, used for amplifying the oscillation driving signal; The base signal generating module is used to generate a radio frequency base signal according to the received oscillation driving signal to ensure that the frequency and phase of the radio frequency signal match the requirements of the synchrocyclotron accelerator.

2. The radio frequency signal control device according to claim 1, characterized in that: The driving signal of the phase detection module is directly amplified by the signal amplification module, and then drives the base signal generation module to generate a radio frequency base signal.

3. The radio frequency signal control device according to claim 1, characterized in that: The device further comprises an analog-to-digital conversion module and a digital-to-analog conversion module; the analog-to-digital conversion module is used to perform analog-to-digital conversion on the oscillation drive signal; the digital-to-analog conversion module is used to convert a digital signal into an analog signal; The driving signal of the phase detection module is converted into a digital signal by the analog-to-digital conversion module and then enters the main control module. After being processed by the main control module, it is converted into digital and amplified, and finally drives the base signal generation module to generate a radio frequency base signal.

4. The radio frequency signal control device according to claim 1, characterized in that: The device also includes a calibration module, which is used to calibrate the frequency points of the radio frequency scanning cycle through the radio frequency power signal; The radio frequency power signal includes radio frequency on, radio frequency off and ion source on; the calibration module controls the radio frequency power on time interval and the ion source on time in each scanning cycle.

5. The radio frequency signal control device according to claim 1, characterized in that: The device also includes an amplitude modulation module for adjusting the gain of the RF base signal; the amplitude modulation module includes a step attenuator and a digitally adjustable gain device, the RF base signal is attenuated by the step attenuator, and the attenuated signal is amplified again by the digitally adjustable gain device.

6. The radio frequency signal control device according to claim 5, characterized in that: The amplitude modulation module further includes a time slice division unit, which is used to divide the power amplification time interval into a plurality of time slices and control the loaded gain signal in each time slice.

7. The radio frequency signal control device according to claim 5, characterized in that: The device also includes a remote interaction module, through which the amplitude gain of the digital adjustable gain device is controlled.

8. The radio frequency signal control device according to claim 1, characterized in that: The device further comprises a fixed attenuator and / or a hardware safety interlocking module, wherein the fixed attenuator is used to limit the maximum output amplitude of the radio frequency signal; The hardware safety interlocking module is used to safely cut off the radio frequency signal; or send the modulated radio frequency signal to the radio frequency amplifier.

9. A radio frequency system for realizing ion acceleration control of a synchrocyclotron accelerator, characterized in that: The system comprises: A radio frequency power amplifier, used to amplify the input low-amplitude radio frequency signal by a fixed gain multiple and then output it into the radio frequency cavity; RF cavity, used for RF signal transmission and proton bunch energy conversion; The RF signal control device described in any one of claims 1-8 is used to obtain a sampling signal, provide real-time feedback of a power value and a phase error, and generate a driving signal based on the power value and the phase error to control the operation of the RF power amplification device and the RF cavity, thereby realizing closed-loop control of the RF signal.

10. A particle radiation therapy system, characterized in that: include: an ion source for generating an ion beam; The radio frequency system of claim 9 is used to provide a radio frequency signal to generate an accelerating electric field for accelerating the ion beam to a desired energy level.

11. A radio frequency signal control method for realizing closed-loop control of radio frequency signals of a synchrocyclotron accelerator, the method being realized by the radio frequency signal control device according to any one of claims 1 to 8, characterized in that: include: Real-time acquisition of the signal of the radio frequency cavity and the incident power and the reflected power on the directional coupler, wherein the signal of the radio frequency cavity includes the D-box power; detecting the phase error between the incident power and the D-box power in real time, and generating an oscillating driving signal when the phases match; The base signal generating module is driven by the driving signal to obtain a radio frequency base signal.

12. The radio frequency signal control method according to claim 11, characterized in that: The step of driving the base signal generating module by the driving signal to obtain the radio frequency base signal comprises: The driving signal is directly amplified to drive the base signal generating module to obtain a radio frequency base signal.

13. The radio frequency signal control method according to claim 11, characterized in that: The step of driving the base signal generating module by the driving signal to obtain the radio frequency base signal comprises: The driving signal is converted into a digital signal by the analog-to-digital conversion module and then enters the main control module. After being processed by the main control chip, it is converted into digital and amplified, and finally drives the base signal generation module to generate a radio frequency base signal.

14. The radio frequency signal control method according to claim 11, characterized in that: The method further comprises: The frequency point of the radio frequency scanning cycle is calibrated by the radio frequency power signal; the radio frequency power signal includes turning on the radio frequency, turning off the radio frequency and turning on the ion source; In each scanning cycle, the on-time interval of the RF power and the on-time of the ion source are controlled.

15. The radio frequency signal control method according to claim 11, characterized in that: The method further comprises: The gain of the radio frequency base signal is adjusted by an amplitude modulation module, wherein the amplitude modulation module includes a step attenuator and a digital adjustable gain device, the radio frequency base signal is attenuated by the step attenuator, and the attenuated signal is amplified again by the digital adjustable gain device; The power amplification time interval is divided into multiple time slices, and the loaded gain signal is controlled in each time slice; The amplitude gain of the digital adjustable gain controller is controlled through a remote interaction module; Limiting the maximum output amplitude of the RF signal by a fixed attenuator; It is determined whether the modulated RF signal meets the preset conditions. If so, the modulated RF signal is sent to the RF amplifier; if not, the RF signal is safely cut off.

16. An ion source automatic beam adjustment method, applicable to the particle radiation therapy system according to claim 10, characterized in that: The method comprises: Setting initialization parameters, including frequency parameters of a radio frequency power signal, so that the accelerator can operate stably; wherein the radio frequency power signal includes turning on the radio frequency, turning off the radio frequency, and turning on the ion source; Monitor and adjust multiple control parameters in real time to obtain the optimal control parameter combination; Under the optimal control parameter combination, the change amount of each control parameter before and after adjustment and the performance change of the proton beam are obtained; according to the change amount of each parameter before and after adjustment and the performance change of the proton beam, a pulse width charge test is performed; The optimal adjustment parameters and adjustment amount are obtained through the test results; and automatic beam adjustment is achieved through the optimal adjustment parameters and adjustment amount.

17. The ion source automatic beam adjustment method according to claim 16, characterized in that: The real-time monitoring and adjusting of control parameters; obtaining an optimal control parameter combination includes: Adjusting the DC bias voltage to suppress secondary electron emission; After the DC bias voltage is regulated, the amplitude modulation value is adjusted and the hydrogen flow rate is adjusted synchronously; Adjusts the adaptive coil position and operating frequency of the rotary capacitor motor; The optimal control parameter combination is obtained by adjusting the results.

18. The ion source automatic beam adjustment method according to claim 16, characterized in that: The real-time monitoring and adjusting of control parameters; obtaining an optimal control parameter combination includes: Through historical data, the influence curve of each control parameter on each beam characteristic is obtained; According to the influence curve of each control parameter on each beam characteristic, a first adjustment range of each control parameter is set; Within the first adjustment range, a plurality of continuous control points are set for each control parameter; By continuously controlling the points and adjusting the control parameters, the real-time beam characteristic change trend can be obtained; Obtaining a second adjustment range of each control parameter through a real-time beam characteristic change trend; Within the second adjustment range, adjust each control point of each control parameter one by one; Real-time monitoring of the values ​​of relevant control parameters before and after adjustment, and by comparing the beam characteristics under different parameter combinations, determining further adjustment parameters and adjustment amounts; The optimal control parameter combination is obtained through iterative adjustment.

19. An electronic device, characterized in that: The electronic device comprises a memory and a processor, the memory stores a computer program, and the processor implements the function of the device of any one of claims 1 to 8 or performs the steps of the method of any one of claims 11 to 18 when executing the computer program.

20. A computer-readable storage medium, characterized in that: The storage medium stores computer instructions. When a computer reads the computer instructions, the computer implements the function of the device according to any one of claims 1 to 8 or executes the steps of the method according to any one of claims 11 to 18.

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