A medical cyclotron frequency modulation method and system

Abstract

The present invention relates to the field of accelerator technology, and specifically to a frequency modulation method and system for a medical cyclotron accelerator, comprising: collecting radio frequency signals and their output powers corresponding to each frequency segment; obtaining the amplitude spectrum and phase spectrum of the high-frequency components in the radio frequency signal, and obtaining the noise factor remaining during the modulation process; obtaining the power consumption factor of the high-frequency cavity resonance process based on the phase and amplitude in the radio frequency signal and the high-frequency cavity power signal, and obtaining the resonance response error of the radio frequency signal in combination with the noise factor remaining during the modulation process, thereby updating the resonance frequency modulation medical cyclotron accelerator. The present invention obtains the resonance response error of the radio frequency signal by analyzing the noise factor and power consumption factor remaining during the modulation process, and thus modulates the frequency to more stably convert the radio frequency signal into an electric field, thereby enabling the medical cyclotron accelerator to operate efficiently and stably.

Description

Technical Field

[0001] The present invention relates to the technical field of accelerators, and in particular to a frequency modulation method and system for a medical cyclotron accelerator. Background Art

[0002] One of the core devices of a medical cyclotron is the radio frequency (RF) system. The core of the RF system is the RF source, which generates a stable, high-power RF signal. This signal is then converted into an electric field, which is then used to accelerate charged particles. To better accelerate charged particles, the phase and frequency of the RF signal need to be precisely controlled to better match the cyclotron frequency of the charged particles. However, the equipment that collects RF signals is easily affected by the environment and generates noise. Therefore, denoising is usually performed during RF signal transmission. However, to avoid losing RF signal power, the denoising filter threshold is often relatively loose, resulting in residual noise. After the RF signal reaches the high-frequency cavity, it undergoes a complex resonance and amplification process. The errors caused by the residual noise will directly affect the stability of the electric field after resonance and amplification, ultimately resulting in unsatisfactory acceleration of charged particles and unstable operation of the medical cyclotron. Summary of the Invention

[0003] The present invention provides a medical cyclotron frequency modulation method and system to solve the existing problem: when noise in a radio frequency signal is removed, the frequency is modulated using only the radio frequency signal after the denoising operation. However, the error caused by the residual noise will cause the medical cyclotron to accelerate charged particles unsatisfactorily and cause unstable operation after resonance and amplification.

[0004] A medical cyclotron frequency modulation method and system of the present invention adopts the following technical solutions:

[0005] One embodiment of the present invention provides a method for frequency modulation of a medical cyclotron, the method comprising the following steps:

[0006] Collect the RF signals of each frequency segment and the output power of each RF signal segment during the modulation process;

[0007] Obtaining the amplitude spectrum and phase spectrum of the high-frequency component in each segment of the RF signal; obtaining the principal component expression factor of the high-frequency component in each segment of the RF signal based on adjacent frequencies in the amplitude spectrum and phase spectrum of the high-frequency component in the RF signal; obtaining the possibility of noise attachment in each segment of the RF signal based on the correlation between the amplitude spectrum and phase spectrum of the high-frequency component in the RF signal; obtaining the residual noise factor in the modulation process based on the possibility of noise attachment in the RF signal, in combination with the principal component expression factor of the high-frequency component in the RF signal and the output power corresponding to the RF signal;

[0008] Obtaining a high-frequency cavity power signal of the radio frequency signal, and obtaining a power consumption factor of the high-frequency cavity resonance process according to the phase and amplitude of the radio frequency signal and the high-frequency cavity power signal;

[0009] The resonance response error of the radio frequency signal is obtained according to the residual noise factor in the modulation process and the power consumption factor in the high-frequency cavity resonance process; the resonance frequency is updated according to the resonance response error of the radio frequency signal, and the medical cyclotron is modulated accordingly.

[0010] Preferably, the specific method of obtaining the amplitude spectrum and phase spectrum of the high-frequency component in each segment of the radio frequency signal includes:

[0011] A high-pass filter is used to obtain the high-frequency components in the entire RF signal; a frequency domain signal of the high-frequency components in each RF signal is obtained through a spectrum analyzer; and an amplitude spectrum and a phase spectrum of the high-frequency components in each RF signal are obtained based on the frequency domain signal.

[0012] Preferably, the obtaining of the principal component expression factor of the high-frequency component in each segment of the radio frequency signal includes the following specific calculation formula:

[0013]

[0014] Where, The principal component expression factor representing the high-frequency component in the radio frequency signal of any frequency corresponding segment; Represents the variance of the spacing between all adjacent frequencies in the amplitude spectrum of the high-frequency component in the radio frequency signal; Represents the mean value of the spacing between all adjacent frequencies in the amplitude spectrum of the high-frequency component in the radio frequency signal; Represents the variance of the spacing between all adjacent frequencies in the phase spectrum of the high-frequency component in the radio frequency signal; Represents the average value of the spacing between all adjacent frequencies in the phase spectrum of the high-frequency component in the radio frequency signal; Represents the Euclidean norm operation.

[0015] Preferably, the method of obtaining the possibility of noise being attached to each radio frequency signal segment includes:

[0016] The absolute value of the Pearson correlation coefficient between the phase spectrum and the amplitude spectrum of the radio frequency signal is used as the possibility of noise being attached to the radio frequency signal.

[0017] Preferably, the noise factor remaining in the modulation process is obtained, and the specific calculation formula included is:

[0018]

[0019] Where, Represents the noise factor remaining in the modulation process; Indicates the number of frequencies in the modulation process; Indicates the The possibility of noise being attached to the RF signal in the frequency corresponding segment; Indicates the The principal component expression factor of the high-frequency component in the radio frequency signal of the frequency segment corresponding to each frequency segment; Indicates the The principal component expression factor of the high-frequency component in the radio frequency signal of the frequency segment corresponding to each frequency segment; Indicates the The output power of the RF signal in the corresponding frequency segment; Indicates the The output power of the RF signal in each frequency segment.

[0020] Preferably, the method of obtaining the high-frequency cavity power signal of the radio frequency signal and obtaining the power consumption factor of the high-frequency cavity resonance process according to the phase and amplitude of the radio frequency signal and the high-frequency cavity power signal includes the following specific methods:

[0021] During the modulation process, each frequency corresponds to a section of radio frequency signal, and the entire power signal obtained when the entire radio frequency signal reaches the high-frequency cavity during the modulation process is used as the high-frequency cavity power signal of the radio frequency signal; the amplitude spectrum and phase spectrum of the entire radio frequency signal are obtained, and the amplitude spectrum and phase spectrum of the high-frequency cavity power signal of the radio frequency signal are obtained; the DTW algorithm is used to match the amplitude spectrum of the high-frequency cavity power signal of the radio frequency signal with the amplitude spectrum of the entire radio frequency signal to obtain several amplitude matching pairs; the phase spectrum of the high-frequency cavity power signal of the radio frequency signal is matched with the phase spectrum of the entire radio frequency signal to obtain several phase matching pairs; and the power consumption factor of the high-frequency cavity resonance process is obtained based on all the amplitude matching pairs and phase matching pairs.

[0022] Preferably, the power consumption factor of the high-frequency cavity resonance process is obtained based on all amplitude matching pairs and phase matching pairs, including the specific calculation formula:

[0023]

[0024] Where, Represents the power consumption factor of the high-frequency cavity resonance process; represents the number of phase-matched pairs; Indicates the The phase of the high frequency cavity power signal of the RF signal in the phase matching pair; Indicates the The phase of the entire RF signal is centered by a phase matching pair; represents the number of amplitude matching pairs; Indicates the The amplitude of the high frequency cavity power signal of the RF signal is matched with the amplitude of the RF signal; Indicates the The amplitude of the entire RF signal is matched with an amplitude pair; Represents the Euclidean norm operation.

[0025] Preferably, the obtaining of the resonance response error of the radio frequency signal includes a specific calculation formula as follows:

[0026]

[0027] Where, Represents the resonant response error of the RF signal; Represents the noise factor remaining in the modulation process; Represents the power consumption factor of the high-frequency cavity resonance process; Indicates the absolute value function; Represents the sigmoid function.

[0028] Preferably, the method of updating the resonant frequency according to the resonant response error of the radio frequency signal and modulating the medical cyclotron accordingly includes the following specific methods:

[0029] The frequency corresponding to the peak of the high-frequency cavity power signal is taken as the default resonant frequency, which is recorded as ;

[0030] The resonance response error is used as the gain coefficient of the default resonance frequency, and the updated resonance frequency is obtained as follows: , to modulate the frequency of the medical cyclotron.

[0031] Another embodiment of the present invention provides a medical cyclotron frequency modulation system, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of any one of the above-mentioned medical cyclotron frequency modulation methods when executing the computer program.

[0032] The beneficial effects of the technical solution of the present invention are as follows: the present application extracts the principal component expression factor of the high-frequency component of the radio frequency signal during continuous frequency modulation by analyzing the spectrum of the radio frequency signal. Since the high-frequency component in the radio frequency signal is most sensitive when modulating the frequency of the radio frequency signal, the present application extracts and analyzes the high-frequency component in the radio frequency signal through a high-pass filter to more accurately extract the residual noise interference in the radio frequency signal; then obtains the noise attachment weight at each modulation frequency, and then obtains the residual noise factor in the modulation process by changing the principal component expression factor of adjacent modulation frequencies and the output power of the radio frequency system during the continuous frequency increase process; further obtains the power consumption factor of the high-frequency cavity resonance process, since the residual noise in the radio frequency signal is the interference of the acquisition equipment reading due to environmental factors, that is, the work actually done by the high-frequency cavity on the radio frequency signal does not include the residual noise in the radio frequency signal, which provides a theoretical basis for the subsequent acquisition of the response error and the modulation of the medical cyclotron; the resonance response error of the radio frequency signal is obtained by the residual noise factor in the modulation process and the power consumption factor of the high-frequency cavity resonance process;

[0033] The resonant frequency of the high-frequency cavity after adjusting the resonance response error can better adapt to the residual interference in the radio frequency signal under continuous frequency modulation, and timely compensate for the errors in the resonance and amplification process of the radio frequency signal, so that the output frequency of the radio frequency system can be modulated faster and more accurately to a state synchronized with the high-frequency cavity, and the radio frequency signal can be more stably converted into an electric field, so as to achieve the purpose of efficient and stable operation of the medical cyclotron. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0035] Figure 1 This is a flow chart of the steps of a medical cyclotron frequency modulation method of the present invention;

[0036] Figure 2 This is an example diagram of the RF signal before denoising;

[0037] Figure 3 This is an example diagram of the RF signal after denoising. DETAILED DESCRIPTION

[0038] To further illustrate the technical means and effectiveness of the present invention in achieving its intended purpose, the following, in conjunction with the accompanying drawings and preferred embodiments, describes in detail a medical cyclotron frequency modulation method and system according to the present invention, including its specific implementation, structure, features, and effectiveness. In the following description, different references to "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics of one or more embodiments may be combined in any suitable manner.

[0039] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0040] The following describes in detail a medical cyclotron frequency modulation method and system provided by the present invention with reference to the accompanying drawings.

[0041] See also Figure 1 , which shows a flowchart of a method for frequency modulation of a medical cyclotron provided by one embodiment of the present invention, the method comprising the following steps:

[0042] Step S001: collecting radio frequency signals of each frequency segment and the output power corresponding to each radio frequency signal segment during the modulation process.

[0043] It should be noted that one of the core devices of the medical cyclotron is the radio frequency system. The core of the radio frequency system is the radio frequency source, which generates a stable and high-power radio frequency signal, and then converts the radio frequency signal into an electric field, and accelerates the charged particles through the electric field. However, the equipment that collects the radio frequency signal is easily affected by the environment and generates noise. Therefore, denoising is usually performed during the transmission of the radio frequency signal. However, in order not to lose the power of the radio frequency signal, the filtering threshold for denoising is often relatively loose, so there is residual noise. If only the radio frequency signal after the denoising operation is used to modulate the frequency, the error caused by the residual noise will be after resonance and amplification, resulting in the medical cyclotron accelerating charged particles. The effect is not ideal and the operation is unstable. Therefore, this application proposes a frequency modulation method for a medical cyclotron, which analyzes the radio frequency signal to improve the stability of the electric field energy.

[0044] Specifically, start the cyclotron system according to the operating manual, monitor the startup status of each system to ensure everything is normal, and pay special attention to the startup of the radio frequency system and magnetic field system;

[0045] Furthermore, on the control panel, set the initial frequency value to ; Set the modulation depth of the RF system to , the modulation rate is set to , 、 、 They are the preset initial frequency, modulation depth and modulation rate, 、 、 The specific value of can be set according to the actual situation. This embodiment does not make a hard requirement. 、 、 Take this as an example to describe;

[0046] The frequency of the RF signal is continuously modulated, and the RF signal at each frequency is collected in real time. During the modulation process, each frequency corresponds to a segment of the RF signal. The RF signals of all frequency-corresponding segments are sorted in ascending order according to frequency. At the same time, a power meter is used to collect the output power corresponding to the RF signals of all frequency-corresponding segments.

[0047] During the frequency modulation process, the RF signal and the output power corresponding to each RF signal segment are collected in real time;

[0048] Furthermore, the collected radio frequency signal is filtered and denoised. In this embodiment, wavelet transform denoising is used to denoise the collected radio frequency signal. The specific denoising algorithm can be selected according to the actual situation and is not limited in this embodiment. At the same time, wavelet transform denoising is a well-known technology, so it will not be described in detail in this embodiment. Figure 2 、 Figure 3 As shown, Figure 2 This is an example of the RF signal before denoising. Figure 3 This is an example of the RF signal after denoising.

[0049] Step S002: Obtain the amplitude spectrum and phase spectrum of the high-frequency component in each segment of the RF signal; obtain the principal component expression factor of the high-frequency component in each segment of the RF signal based on the adjacent frequencies in the amplitude spectrum and phase spectrum of the high-frequency component in the RF signal; obtain the possibility of attached noise in each segment of the RF signal based on the correlation between the amplitude spectrum and phase spectrum of the high-frequency component in the RF signal; obtain the residual noise factor in the modulation process based on the possibility of attached noise in the RF signal, combined with the principal component expression factor of the high-frequency component in the RF signal and the output power corresponding to the RF signal.

[0050] It should be noted that when the medical cyclotron accelerator is working normally, the high-frequency cavity should be in a resonant state. The resonant state refers to the phenomenon that the system exhibits maximum vibration response at a certain specific frequency; at this frequency, the electromagnetic field intensity inside the high-frequency cavity is the largest, which is most conducive to accelerating charged particles. By modulating the frequency of the radio frequency signal input into the high-frequency cavity by the radio frequency source, the frequency of the radio frequency signal input into the high-frequency cavity is accurately matched with the resonant frequency of the high-frequency cavity, thereby forming a stable electric field in the high-frequency cavity.

[0051] It should be further explained that in the process of frequency modulation, the components in the RF signal are always changing, so it is difficult to directly obtain the residual noise components in the RF signal during the modulation process. Therefore, this application analyzes the RF signal in the continuous modulation process and its corresponding power signal to extract the residual noise interference in the RF signal; and since the frequency of the RF signal is modulated, it is most sensitive to the high-frequency components in the RF signal. Therefore, this application extracts and analyzes the high-frequency components in the RF signal through a high-pass filter to more accurately extract the residual noise interference in the RF signal.

[0052] Preferably, in a specific embodiment of the present invention, each segment of the RF signal has a corresponding modulation frequency; a high-pass filter is used to obtain the high-frequency components in the entire RF signal; a frequency domain signal of the high-frequency components in each segment of the RF signal is obtained through a spectrum analyzer, and the spectrum analyzer can convert the RF signal in the time domain into a frequency domain signal; the amplitude spectrum and phase spectrum of the high-frequency components in each segment of the RF signal are obtained according to the frequency domain signal. Obtaining the amplitude spectrum and phase spectrum through the frequency domain signal is a well-known prior art, so it will not be repeated in this embodiment.

[0053] Furthermore, according to the amplitude spectrum and phase spectrum of the high-frequency component in the radio frequency signal, the principal component expression factor of the high-frequency component in the radio frequency signal is obtained. The specific calculation formula is:

[0054]

[0055] Where, The principal component expression factor representing the high-frequency component in the radio frequency signal of any frequency corresponding segment; Represents the variance of the spacing between all adjacent frequencies in the amplitude spectrum of the high-frequency component in the radio frequency signal; Represents the mean value of the spacing between all adjacent frequencies in the amplitude spectrum of the high-frequency component in the radio frequency signal; Represents the variance of the spacing between all adjacent frequencies in the phase spectrum of the high-frequency component in the radio frequency signal; Represents the average value of the spacing between all adjacent frequencies in the phase spectrum of the high-frequency component in the radio frequency signal; Represents the Euclidean norm operation.

[0056] It should be noted that and The smaller the value, the more concentrated the distribution of amplitude and phase in the amplitude spectrum and phase spectrum of the high-frequency components in the RF signal, and the more it can indicate that most of the high-frequency components are RF signals; since the probability of noise distribution at each position in the RF signal is equal, that is, the distribution of noise in the RF signal is regular, and The larger the value is, the more irregular the distribution of amplitude and phase in the amplitude spectrum and phase spectrum of the high-frequency components in the RF signal will be, and the components represented by it will be able to clearly represent the RF signal. The larger the value of is, the more it can indicate that most of the high-frequency components are RF signals, and the information contained in the RF signals is clear; and because the measurement units of amplitude and phase are different, further and The sum is integrated by performing the Euclidean norm operation.

[0057] It should be further explained that when the frequency of the RF signal is modulated, several RF signals at different frequencies are obtained, and some RF signals may be more susceptible to noise. That is, the possibility of noise being attached to RF signals of different frequencies is different. In order to make the electric field converted by the RF signal more stable, it is necessary to obtain the possibility of noise being attached to the RF signal of each frequency. Since the phase of the RF signal will change when the frequency of the RF signal is modulated, and the amplitude of the RF signal will not change, the less correlation there is between the phase spectrum and the amplitude spectrum of the RF signal, the less new amplitude is mixed into the RF signal, that is, no noise is received. Therefore, the possibility of noise being attached to the RF signal of each frequency can be obtained.

[0058] Preferably, in a specific embodiment of the present invention, for the RF signal of any frequency corresponding segment, the absolute value of the Pearson correlation coefficient between the phase spectrum and the amplitude spectrum of the RF signal is used as the possibility of attached noise in the RF signal; since the Pearson correlation coefficient is a well-known prior art, it will not be described in detail in this embodiment.

[0059] It should be noted that in a medical cyclotron accelerator, the radio frequency signal is converted into a radio frequency electric field, so that charged particles are continuously accelerated in the radio frequency electric field. When there is noise in the radio frequency signal, the radio frequency electric field converted from the main component of the high-frequency component of the radio frequency signal will become unstable, which will eventually manifest as unstable output power of the radio frequency system. Therefore, the residual noise factor in the modulation process can be obtained by continuously modulating the frequency, the output power of the radio frequency system, the main component expression factor of the high-frequency component of the radio frequency signal, and the possibility of noise attachment in the radio frequency signal.

[0060] Preferably, in a specific embodiment of the present invention, the residual noise factor in the modulation process is obtained according to the output power of the radio frequency system, the main component expression factor of the high-frequency component in the radio frequency signal, and the possibility of noise being attached to the radio frequency signal of the frequency. The specific calculation formula is:

[0061]

[0062] Where, Represents the noise factor remaining in the modulation process; Indicates the number of frequencies in the modulation process; Indicates the The possibility of noise being attached to the RF signal in the frequency corresponding segment; Indicates the The principal component expression factor of the high-frequency component in the radio frequency signal of the frequency segment corresponding to each frequency segment; Indicates the The principal component expression factor of the high-frequency component in the radio frequency signal of the frequency segment corresponding to each frequency segment; Indicates the The output power of the RF signal in the corresponding frequency segment; Indicates the The output power of the RF signal in each frequency segment.

[0063] It should be noted that In the figure, the larger the numerator and the smaller the denominator, it means that as the modulation frequency increases, the effective information contained in the high-frequency main component of the RF signal becomes more prominent. This signal must have higher processing value and processing efficiency, but the output power of the RF system decreases, which means that the environmental noise affects the matching degree between the RF signal and the resonant frequency of the high-frequency cavity; further, the environmental noise attachment weight is used to weightedly average it to obtain the residual noise factor in the modulation process of the medical cyclotron frequency modulation process.

[0064] At this point, the noise factor remaining in the modulation process is obtained.

[0065] Step S003: obtaining a high-frequency cavity power signal of the radio frequency signal, and obtaining a power consumption factor of the high-frequency cavity resonance process according to the phase and amplitude of the radio frequency signal and the high-frequency cavity power signal.

[0066] It should be noted that the RF system is responsible for generating an RF electric field in the cyclotron. This RF electric field is used to accelerate particles in the high-frequency cavity, which is a resonator that converts the RF signal provided by the RF system into a high-intensity electric field. Since environmental noise exists during the process of generating RF signals through power modulation of the RF system, it will affect the frequency matching degree of the RF signal in the high-frequency cavity and the energy conversion effect. Once the resonant amplification process converts excess noise, it will further amplify the noise and error. Therefore, a spectrum analyzer is used to perform frequency domain conversion on the power signal to obtain its phase spectrum and amplitude spectrum. This is used to obtain the work done by the high-frequency cavity on the RF signal. The residual noise in the RF signal is the interference of environmental factors on the reading of the acquisition equipment. In fact, the work done by the high-frequency cavity on the RF signal does not include the residual noise in the RF signal, which provides a theoretical basis for the subsequent acquisition of response errors and the modulation of medical cyclotrons.

[0067] Preferably, in a specific embodiment of the present invention, each frequency corresponds to a section of RF signal during the modulation process, and the RF signal corresponding to each frequency will obtain a power signal when it reaches the high-frequency cavity, then the entire power signal obtained when the entire RF signal reaches the high-frequency cavity during the modulation process is used as the high-frequency cavity power signal of the RF signal; the amplitude spectrum and phase spectrum of the entire RF signal are obtained, and the amplitude spectrum and phase spectrum of the high-frequency cavity power signal of the RF signal are obtained; the amplitude spectrum of the high-frequency cavity power signal of the RF signal is matched with the amplitude spectrum of the entire RF signal using the DTW algorithm to obtain several amplitude matching pairs; the phase spectrum of the high-frequency cavity power signal of the RF signal is matched with the phase spectrum of the entire RF signal to obtain several phase matching pairs; according to all amplitude matching pairs and phase matching pairs, the power consumption factor of the high-frequency cavity resonance process is obtained, and the specific calculation formula is:

[0068]

[0069] Where, Represents the power consumption factor of the high-frequency cavity resonance process; represents the number of phase-matched pairs; Indicates the The phase of the high frequency cavity power signal of the RF signal in the phase matching pair; Indicates the The phase of the entire RF signal is centered by a phase matching pair; represents the number of amplitude matching pairs; Indicates the The amplitude of the high frequency cavity power signal of the RF signal is matched with the amplitude of the RF signal; Indicates the The amplitude of the entire RF signal is matched with an amplitude pair; Represents the Euclidean norm operation.

[0070] It should be noted that Representative The phase of the high frequency cavity power signal in the first phase matching pair is The ratio of the phases of the RF signals in the two phase-matched pairs, that is, the resonance process is a phase alignment process, so the ratio of the two is the work done by the high-frequency cavity to adjust the resonance of the RF signal to be synchronized with its power signal; Representative The amplitude of the high frequency cavity power signal in the first amplitude matching pair is The ratio of the amplitudes of the RF signals in the two phase-matched pairs is the work done by the high-frequency cavity on the RF signal, which amplifies it several times. After averaging the two, the Euclidean norm is calculated to obtain the total work done by the high-frequency cavity on the continuously frequency modulated RF signal, and the power consumption factor of the high-frequency cavity resonance process is obtained.

[0071] At this point, the power consumption factor of the high-frequency cavity resonance process is obtained.

[0072] Step S004: Obtain the resonance response error of the radio frequency signal according to the noise factor remaining in the modulation process and the power consumption factor of the high-frequency cavity resonance process; update the resonance frequency according to the resonance response error of the radio frequency signal, and modulate the medical cyclotron accordingly.

[0073] It should be noted that, during normal operation of the high-frequency cavity in the medical cyclotron, in order to compensate for the resonance response error caused by the residual noise that the radio frequency signal is subjected to before entering the high-frequency cavity, and to make the electric field converted from the radio frequency signal more stable, it is necessary to further increase the resonance frequency of the high-frequency cavity to make up for its resonance response error. After obtaining the noise factor remaining in the modulation process and the power consumption factor of the high-frequency cavity resonance process respectively through steps S002 and S003, since the residual noise in the radio frequency signal is the interference of environmental factors on the reading of the acquisition device, that is, the work actually done by the high-frequency cavity on the radio frequency signal does not include the residual noise in the radio frequency signal, the resonance response error of the radio frequency signal can be obtained, and based on the resonance response error, the frequency of the radio frequency signal can be further adjusted to make the electric field converted from the radio frequency signal more stable.

[0074] Preferably, in a specific embodiment of the present invention, the resonance response error of the RF signal is obtained based on the residual noise factor in the RF signal and the power consumption factor of the high-frequency cavity resonance process, and the specific calculation formula is:

[0075]

[0076] Where, Represents the resonant response error of the RF signal; Represents the noise factor remaining in the modulation process; Represents the power consumption factor of the high-frequency cavity resonance process; Indicates the absolute value function; represents a sigmoid function, which is used for normalization processing in this embodiment.

[0077] Furthermore, the power signal curve of the high-frequency cavity, the frequency corresponding to the peak is the default resonant frequency, recorded as ;

[0078] The resonance response error is used as the gain coefficient of the default resonance frequency, and the updated resonance frequency is obtained as follows: , to modulate the frequency of the medical cyclotron. Modulating the frequency of the medical cyclotron is a well-known prior art, so it will not be described in detail in this embodiment.

[0079] The resonant frequency of the high-frequency cavity after adjusting the resonance response error can better adapt to the residual interference in the radio frequency signal under continuous frequency modulation, and timely compensate for the errors in the resonance and amplification process of the radio frequency signal, so that the output frequency of the radio frequency system can be modulated faster and more accurately to a state synchronized with the high-frequency cavity, and the radio frequency signal can be more stably converted into an electric field, so as to achieve the purpose of efficient and stable operation of the medical cyclotron.

[0080] Another embodiment of the present invention provides a medical cyclotron frequency modulation system, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, a medical cyclotron frequency modulation method in steps S001 to S004 is implemented.

[0081] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A medical cyclotron frequency modulation method, characterized in that: The method comprises the following steps: Collect the RF signals of each frequency segment and the output power of each RF signal segment during the modulation process; Obtaining the amplitude spectrum and phase spectrum of the high-frequency component in each segment of the RF signal; obtaining the principal component expression factor of the high-frequency component in each segment of the RF signal based on adjacent frequencies in the amplitude spectrum and phase spectrum of the high-frequency component in the RF signal; obtaining the possibility of noise attachment in each segment of the RF signal based on the correlation between the amplitude spectrum and phase spectrum of the high-frequency component in the RF signal; obtaining the residual noise factor in the modulation process based on the possibility of noise attachment in the RF signal, in combination with the principal component expression factor of the high-frequency component in the RF signal and the output power corresponding to the RF signal; Obtaining a high-frequency cavity power signal of the radio frequency signal, and obtaining a power consumption factor of the high-frequency cavity resonance process according to the phase and amplitude of the radio frequency signal and the high-frequency cavity power signal; Obtaining a resonance response error of the radio frequency signal based on a residual noise factor in the modulation process and a power consumption factor in the high-frequency cavity resonance process; updating the resonance frequency based on the resonance response error of the radio frequency signal, and modulating the medical cyclotron accordingly; The specific calculation formula for obtaining the principal component expression factor of the high-frequency component in each segment of the radio frequency signal is as follows: Where, The principal component expression factor representing the high-frequency component in the radio frequency signal of any frequency corresponding segment; Represents the variance of the spacing between all adjacent frequencies in the amplitude spectrum of the high-frequency component in the radio frequency signal; Represents the mean value of the spacing between all adjacent frequencies in the amplitude spectrum of the high-frequency component in the radio frequency signal; Represents the variance of the spacing between all adjacent frequencies in the phase spectrum of the high-frequency component in the radio frequency signal; Represents the average value of the spacing between all adjacent frequencies in the phase spectrum of the high-frequency component in the radio frequency signal; Represents the Euclidean norm operation; The specific method of obtaining the possibility of attached noise in each RF signal segment includes: Taking the absolute value of the Pearson correlation coefficient between the phase spectrum and the amplitude spectrum of the radio frequency signal as the possibility of attached noise in the radio frequency signal; The noise factor remaining in the modulation process is obtained, and the specific calculation formula is as follows: Where, Represents the noise factor remaining in the modulation process; Indicates the number of frequencies in the modulation process; Indicates the The possibility of noise being attached to the RF signal in the frequency corresponding segment; Indicates the The principal component expression factor of the high-frequency component in the radio frequency signal of the frequency segment corresponding to each frequency segment; Indicates the The principal component expression factor of the high-frequency component in the radio frequency signal of the frequency segment corresponding to each frequency segment; Indicates the The output power of the RF signal in the corresponding frequency segment; Indicates the The output power of the RF signal in each frequency segment.

2. A medical cyclotron frequency modulation method according to claim 1, characterized in that: The specific method of obtaining the amplitude spectrum and phase spectrum of the high-frequency component in each segment of the radio frequency signal includes: A high-pass filter is used to obtain the high-frequency components in the entire RF signal; a frequency domain signal of the high-frequency components in each RF signal is obtained through a spectrum analyzer; and an amplitude spectrum and a phase spectrum of the high-frequency components in each RF signal are obtained based on the frequency domain signal.

3. A medical cyclotron frequency modulation method according to claim 1, characterized in that: The method of obtaining the high-frequency cavity power signal of the radio frequency signal and obtaining the power consumption factor of the high-frequency cavity resonance process according to the phase and amplitude of the radio frequency signal and the high-frequency cavity power signal includes the following specific methods: During the modulation process, each frequency corresponds to a section of radio frequency signal, and the entire power signal obtained when the entire radio frequency signal reaches the high-frequency cavity during the modulation process is used as the high-frequency cavity power signal of the radio frequency signal; the amplitude spectrum and phase spectrum of the entire radio frequency signal are obtained, and the amplitude spectrum and phase spectrum of the high-frequency cavity power signal of the radio frequency signal are obtained; the DTW algorithm is used to match the amplitude spectrum of the high-frequency cavity power signal of the radio frequency signal with the amplitude spectrum of the entire radio frequency signal to obtain several amplitude matching pairs; the phase spectrum of the high-frequency cavity power signal of the radio frequency signal is matched with the phase spectrum of the entire radio frequency signal to obtain several phase matching pairs; and the power consumption factor of the high-frequency cavity resonance process is obtained based on all the amplitude matching pairs and phase matching pairs.

4. A medical cyclotron frequency modulation method according to claim 3, characterized in that: The power consumption factor of the high-frequency cavity resonance process is obtained based on all amplitude matching pairs and phase matching pairs, including the specific calculation formula: Where, Represents the power consumption factor of the high-frequency cavity resonance process; represents the number of phase-matched pairs; Indicates the The phase of the high frequency cavity power signal of the RF signal in the phase matching pair; Indicates the The phase of the entire RF signal is centered by a phase matching pair; represents the number of amplitude matching pairs; Indicates the The amplitude of the high frequency cavity power signal of the RF signal is matched with the amplitude of the RF signal; Indicates the The amplitude of the entire RF signal is matched with an amplitude pair; Represents the Euclidean norm operation.

5. The medical cyclotron frequency modulation method according to claim 1, characterized in that: The specific calculation formula for obtaining the resonance response error of the radio frequency signal is as follows: Where, Represents the resonant response error of the RF signal; Represents the noise factor remaining in the modulation process; Represents the power consumption factor of the high-frequency cavity resonance process; Indicates the absolute value function; Represents the sigmoid function.

6. A medical cyclotron frequency modulation method according to claim 5, characterized in that: The specific method of updating the resonant frequency according to the resonant response error of the radio frequency signal and modulating the medical cyclotron accelerator is as follows: The frequency corresponding to the peak of the high-frequency cavity power signal is taken as the default resonant frequency, which is recorded as ; The resonance response error is used as the gain coefficient of the default resonance frequency, and the updated resonance frequency is obtained as follows: , to modulate the frequency of the medical cyclotron.

7. A medical cyclotron frequency modulation system comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the computer program is executed by a processor, the steps of the medical cyclotron frequency modulation method according to any one of claims 1 to 6 are implemented.

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