CN117815546B - Tunable multi-frequency coupling deep tissue electrical stimulation system, method and storage medium - Google Patents

Abstract

The present invention provides a tunable multi-frequency coupled deep tissue electrical stimulation system, method and storage medium, the system comprising: a signal control module, comprising a single chip microcomputer; a signal generation module, comprising a signal generator and a first low-pass filter, the input end of the signal generator is connected to the output end of the single chip microcomputer, the single chip microcomputer controls the signals of each channel output by the signal generator to achieve the adjustment of the electrical stimulation signal parameters, the input end of the first low-pass filter is connected to the output end of the signal generator; and a signal channel module, comprising a plurality of signal channels, each signal channel comprising a phase shifter and a voltage-current converter, the phase shifter of each signal channel is connected to the output end of the first low-pass filter and the single chip microcomputer, the input end of each voltage-current converter is respectively connected to the output end of each phase shifter, and the output end of each voltage-current converter is respectively used to connect to electrodes attached to the body surface. The electrical stimulation system can achieve the adjustable parameters of the electrical stimulation signal.

Description

Tunable multi-frequency coupled deep tissue electrical stimulation system, method and storage medium

Technical Field

The present invention relates to the technical field of non-invasive electrical stimulation, and in particular to a tunable multi-frequency coupled deep tissue electrical stimulation system, method and storage medium.

Background Art

Transcranial electrical stimulation (tES) is a non-invasive electrical stimulation technology that has little negative impact on people's physical and psychological health. It has become a hot topic in brain function research in recent years. According to the stimulation waveform output by transcranial electrical stimulation, it is divided into: transcranial direct current stimulation, transcranial alternating current stimulation, and transcranial random noise stimulation. However, tES cannot stimulate deep tissue areas at present, and due to the divergence of the electric field, it will also lead to the activation of other brain areas. In 2017, Grossman et al. proposed the concept of temporal interference (TI) stimulation, a new non-invasive method for regulating deep brain regions. TI stimulation uses two pairs of slightly different high-frequency currents (such as 2kHz and 2.01kHz) to form a low-frequency, high-intensity oscillating amplitude-modulated electric field in the target area through coherent superposition of high-frequency signals, thereby inducing nerve cell discharges. This method has been shown through in vivo experiments on mice that hippocampal neurons can be activated without the activation of overlying cortical neurons, and can follow the low-frequency envelope of the electric field induced by TI stimulation. In addition, by changing the current input ratio of the two pairs of electrodes, it was found that the movement of the mouse's forepaws, whiskers, and ears can be induced without changing the spatial position of the electrodes. Therefore, TI stimulation can achieve flexible movement of the stimulation target area in the brain without moving the electrodes. In 2020, Li et al. used TI technology to verify the feasibility of the selective muscle nerve stimulation method, in which two current channels can independently stimulate the nerves/muscles that control human fingers, indicating that TI technology can be used in a variety of biological tissues such as the brain and muscles.

Although dual-channel time interference technology can achieve deep tissue stimulation, dual-frequency interference has many shortcomings in principle: such as the duty cycle is too large, the duration of a single stimulation cannot be adjusted, the signal-to-noise ratio is limited, and each channel requires a large current, etc. The main problem is that the existing deep tissue stimulation based on dual-channel time interference technology cannot adjust the parameters of the electrical stimulation signal, making it difficult to ensure the effectiveness and accuracy of deep tissue electrical stimulation. Therefore, how to achieve the adjustable parameters of the electrical stimulation signal is a technical problem that needs to be solved urgently.

Summary of the invention

In view of this, the present invention provides a tunable multi-frequency coupled deep tissue electrical stimulation system, method and storage medium to solve one or more problems existing in the prior art.

According to one aspect of the present invention, the present invention discloses a tunable multi-frequency coupled deep tissue electrical stimulation system, the system comprising:

A signal control module, including a single chip microcomputer;

A signal generating module, comprising a signal generator and a first low-pass filter, wherein the input end of the signal generator is connected to the output end of the single-chip microcomputer, the single-chip microcomputer controls the signals of each channel output by the signal generator to adjust the parameters of the electrical stimulation signal, and the input end of the first low-pass filter is connected to the output end of the signal generator; and

A signal channel module includes multiple signal channels, each of which includes a phase shifter and a voltage-current converter. The phase shifter of each signal channel is connected to the output end of the first low-pass filter and the single-chip microcomputer. Each phase shifter adjusts the phase of the output signal of each signal channel based on a control signal received from the single-chip microcomputer. The input end of each voltage-current converter is respectively connected to the output end of each phase shifter, and the output end of each voltage-current converter is respectively used to connect to an electrode attached to the body surface.

In some embodiments of the present invention, the signal generating module also includes a square wave generator, the input end of the square wave generator is connected to the output end of the single-chip microcomputer, so that the single-chip microcomputer controls the square wave signal output by the square wave generator, and the square wave signal output by the square wave generator is used to perform square wave truncation on the signal output by the signal generator.

In some embodiments of the present invention, the signal generating module further includes a second low-pass filter, and an input end of the second low-pass filter is connected to an output end of the square wave generator.

In some embodiments of the present invention, each of the signal channels further includes a multiplier, which is located between the phase shifter and the voltage-current converter, wherein the input of the multiplier is connected to the output of the phase shifter of the channel to which it belongs and the output of the second low-pass filter, and the output of the multiplier is connected to the input of the voltage-current converter.

In some embodiments of the present invention, the signal generator is a DDS function arbitrary waveform signal generator.

In some embodiments of the present invention, the signal control module further includes a human-computer interaction platform, and the human-computer interaction platform is connected to the single-chip microcomputer.

According to another aspect of the present invention, a tunable multi-frequency coupled deep tissue electrical stimulation method is also disclosed. The tunable multi-frequency coupled deep tissue electrical stimulation method is implemented by the tunable multi-frequency coupled deep tissue electrical stimulation system described in any of the above embodiments.

In some embodiments of the present invention, the single chip microcomputer controls the signals of each channel output by the signal generator to adjust the parameters of the electrical stimulation signal, including:

Acquire the phase of the current signal output by each of the signal channels, and select the phase of the current signal output by one of the signal channels as a reference phase;

Calculating the phase difference between the phase of the current signal output by other channels and the reference phase;

Determining a target phase of a target signal output by each signal channel based on the frequency of the target signal output by each signal channel;

The single chip microcomputer controls the signal of each channel output by the signal generator based on the determined target phase of each signal channel and each phase difference.

In some embodiments of the present invention, the target phase is calculated as follows: Φ=A+Bf+Cf ² +Df ³ + ...; wherein Φ represents the target phase, A, B, C, D are coefficients, and f is the frequency of the target signal output by the signal channel.

According to yet another aspect of the present invention, a computer-readable storage medium is disclosed, on which a computer program is stored. When the program is executed by a processor, the steps of the method described in any of the above embodiments are implemented.

The tunable multi-frequency coupled deep tissue electrical stimulation system, method and storage medium disclosed in the above embodiments, the single-chip control signal generator outputs the signals of each channel, thereby realizing the adjustment of the multi-frequency coupled deep tissue electrical stimulation signal parameters, thereby ensuring the effectiveness and accuracy of the stimulation function. In addition to the above, the present application adopts the square wave truncation method to realize the adjustment of the electrical stimulation signal parameters, which further improves the effectiveness and accuracy of the deep tissue electrical stimulation while ensuring that the multi-frequency coupled deep tissue electrical stimulation signal parameters are adjustable.

Additional advantages, purposes, and features of the present invention will be described in part in the following description, and will become apparent to those skilled in the art after studying the following, or may be learned from the practice of the present invention. The purposes and other advantages of the present invention may be achieved and obtained by the structures specifically pointed out in the written description, claims, and drawings.

Those skilled in the art will appreciate that the objectives and advantages that can be achieved with the present invention are not limited to the above specific description, and the above and other objectives that can be achieved by the present invention will be more clearly understood from the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings described herein are used to provide a further understanding of the present invention, constitute a part of this application, and do not constitute a limitation of the present invention. The components in the drawings are not drawn to scale, but are only for illustrating the principles of the present invention. In order to facilitate the illustration and description of some parts of the present invention, the corresponding parts in the drawings may be enlarged, that is, they may become larger relative to other parts in the exemplary device actually manufactured according to the present invention. In the drawings:

FIG1 is a schematic structural diagram of a tunable multi-frequency coupled deep tissue electrical stimulation system according to an embodiment of the present invention.

FIG. 2 is a schematic structural diagram of a tunable multi-frequency coupled deep tissue electrical stimulation system according to another embodiment of the present invention.

FIG3 is a schematic diagram of a signal waveform for adjusting electrical stimulation signal parameters using a square wave truncation method according to an embodiment of the present invention.

FIG. 4 is a schematic diagram of a signal waveform for adjusting electrical stimulation signal parameters using a multi-frequency coupling method according to an embodiment of the present invention.

FIG. 5 is a schematic diagram of time interference parameters according to an embodiment of the present invention.

FIG6 is a simulation diagram showing the case where the parameters of the electrical stimulation signal are adjusted using the square wave truncation method.

FIG. 7 is a simulation diagram showing the case where the parameters of the electrical stimulation signal are adjusted using the multi-frequency coupling method.

Reference numerals:

Signal control module 100 Signal generation module 200 Signal channel module 300 Single chip microcomputer 110 Human-computer interaction platform 120 Signal generator 211 First low-pass filter 212 Square wave generator 221 Second low-pass filter 222 Phase shifter 310 Multiplier 320 Voltage-to-current converter 330

DETAILED DESCRIPTION

To make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings. Here, the exemplary embodiments of the present invention and their descriptions are used to explain the present invention, but are not intended to limit the present invention.

It should be noted here that in order to avoid obscuring the present invention due to unnecessary details, only structures and/or processing steps closely related to the solutions according to the present invention are shown in the accompanying drawings, while other details that are not closely related to the present invention are omitted.

It should be emphasized that the terms “include/comprises/has” when used herein refer to the presence of features, elements, steps or components, but do not exclude the presence or addition of one or more other features, elements, steps or components.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the accompanying drawings, the same reference numerals represent the same or similar components, or the same or similar steps.

Figure 1 is a structural schematic diagram of a tunable multi-frequency coupled deep tissue electrical stimulation system according to an embodiment of the present invention. As shown in Figure 1, the tunable multi-frequency coupled deep tissue electrical stimulation system may at least include a signal control module 100, a signal generation module 200 and a signal channel module 300.

The signal control module 100 includes a single chip microcomputer 110; the signal generation module 200 includes a signal generator 211 and a first low-pass filter 212, wherein the input end of the signal generator 211 is connected to the output end of the single chip microcomputer 110, the single chip microcomputer 110 controls the signals of each channel output by the signal generator 211 to adjust the parameters of the electrical stimulation signal, and the input end of the first low-pass filter 212 is connected to the output end of the signal generator 211; the signal channel module 300 includes a plurality of signal channels, each of which is connected to the output end of the signal generator 211; The channel includes a phase shifter 310 and a voltage-current converter 330. The phase shifter 310 of each signal channel is connected to the output end of the first low-pass filter 212 and the single-chip microcomputer 110. Each phase shifter 310 adjusts the phase of the output signal of each signal channel based on the control signal received from the single-chip microcomputer 110. The input end of each voltage-current converter 330 is respectively connected to the output end of each phase shifter 310, and the output end of each voltage-current converter 330 is respectively used for connecting to electrodes attached to the surface of the human body.

When the tunable multi-frequency coupled deep tissue electrical stimulation system is used for deep tissue electrical stimulation, multiple pairs of stimulation electrodes are first attached to the human body surface of the tissue to be stimulated at the same time, and a sinusoidal AC electric field with a specific frequency, a specific phase, and a specific amplitude is applied to each pair of electrodes based on the system. When the multi-frequency electric fields meet, interference in the time domain can occur. Further, the frequency, amplitude, and phase of the electric field of each signal channel can be adjusted by the signal control module 100 to achieve the adjustment of the parameters of the electrical stimulation signal. That is, the system is based on multi-frequency coupled time domain interference technology, which can focus the peak value of the change of the electric field envelope on a specific area of the tissue in space, while reducing the voltage output intensity of each channel, without changing the electrode position, and can achieve stimulation mode (activation\inhibition) conversion and stimulation parameter adjustment. Among them, the electrical stimulation signal is a signal of coherent synthesis of the voltage field generated by each signal channel in the biological group.

In addition, for the tunable multi-frequency coupled deep tissue electrical stimulation system in the present application, the adjustable parameters of the electrical stimulation signal may include duty cycle, signal-to-noise ratio, pulse width, etc. FIG5 is a schematic diagram of time interference parameters of an embodiment of the present invention. As shown in FIG5 , for the electrical stimulation signal, the portion greater than the threshold A0 is the activation portion, the portion less than the threshold A0 is the noise portion, the stimulation duration is the activation time period t1, the duty cycle refers to the ratio of the activation time period t1 to the stimulation period t0; the signal-to-noise ratio is the ratio of the peak value A to the maximum value N of the noise portion less than the threshold A0.

The signal control module 100 may specifically include a single-chip microcomputer 110 and a human-computer interaction platform 120. In this embodiment, human-computer interaction can be realized based on the human-computer interaction platform 120, for example, the parameters of the required electrical stimulation signal are input through the human-computer interaction platform 120. The signal control module 100 is used to control the operation of the signal generator 211, that is, by sending a control signal to the signal generator 211, each signal channel outputs a sine wave signal that meets the requirements. Exemplarily, the human-computer interaction platform 120 is connected to the single-chip microcomputer 110. At this time, the parameters of the required electrical stimulation signal can be input through the human-computer interaction platform 120, such as the parameters of the required electrical stimulation signal are a base frequency of 1kHz, a coherent electric field of 1Hz, a duty cycle of 30%, a dual channel, and a noise of 0. Further, the single-chip microcomputer 110 generates a custom signal function based on the parameters of the received input electrical stimulation signal and controls the signals output by each signal channel through the signal generator 211, thereby adjusting the parameters of the output electrical stimulation signal to the parameters of the required electrical stimulation signal.

In another embodiment, referring to FIG. 2 , the signal generating module 200 further includes a square wave generator 221, an input end of the square wave generator 221 being connected to an output end of the single chip microcomputer 110 so that the single chip microcomputer 110 controls the square wave signal output by the square wave generator 221, and the square wave signal output by the square wave generator 221 is used to perform square wave truncation on the signal output by the signal generator 211.

In this embodiment, the signal generating module 200 includes a signal generator 211 and a square wave generator 221, that is, since the signal generator 211 and the square wave generator 221 are both connected to the single chip microcomputer 110 of the signal control module 100, the single chip microcomputer 110 controls the operation of the square wave generator 221 in addition to controlling the signal generator 211. That is, in this embodiment, the system uses a square wave truncation method to adjust the parameters of the electrical stimulation signal, which further improves the effectiveness and accuracy of the deep tissue electrical stimulation while ensuring that the parameters of the multi-frequency coupled deep tissue electrical stimulation signal are adjustable.

Specifically, the signal generator 211 outputs multiple (≥2) signals based on the custom signal function generated by the single-chip microcomputer 110, and the square wave generator 221 outputs a stable square wave signal. At this time, the square wave signal serves as a truncation signal to determine the phase of the final output signal. In this embodiment, the multiple signals output by the signal generator 211 are sinusoidal signals, and the final output signal is the signal output by each channel to the biological tissue; and the number of sinusoidal signals output by the signal generator 211 is equal to the number of signal channels. When the number of signal channels in the system is two, the number of signals output by the signal generator 211 is two, and when the number of signal channels in the system is five, the number of signals output by the signal generator 211 is also five.

Furthermore, the signal generating module 200 further includes a second low-pass filter 222 , and an input end of the second low-pass filter 222 is connected to an output end of the square wave generator 221 .

In one embodiment, each of the signal channels further includes a multiplier 320, the multiplier 320 is located between the phase shifter 310 and the voltage-current converter 330, the input end of the multiplier 320 is connected to the output end of the phase shifter 310 of the channel to which it belongs and the output end of the second low-pass filter 222, and the output end of the multiplier 320 is connected to the input end of the voltage-current converter 330. Referring to FIG1 , the number of signal channels in the tunable multi-frequency coupled deep tissue electrical stimulation system shown in FIG1 is three, and each signal channel includes a phase shifter 310, a multiplier 320, and a voltage-current converter 330. In the system, the input end of the square wave generator 221 is connected to the single-chip microcomputer 110 of the signal control module 100, and the output end of the square wave generator 221 is connected to the input end of the second low-pass filter 222, and the output end of the second low-pass filter 222 is connected to the multipliers 320 in the three signal channels. In this embodiment, the single chip microcomputer 110 controls the signal generator 211 to output three signals, and at the same time, the single chip microcomputer 110 controls the square wave generator 221 to output a square wave signal. At this time, based on the multiplier 320 in each signal channel, the sine wave signal output by each signal channel is multiplied by the square wave signal output by the square wave generator 221 to achieve signal truncation, that is, the adjustment of the electrical stimulation signal parameters is achieved by adjusting the square wave signal output by the square wave generator.

FIG3 is a schematic diagram of a signal waveform of adjusting the parameters of an electrical stimulation signal by a square wave truncation method according to an embodiment of the present invention. In this embodiment, the signal generator 211 generates two sine wave signals, such as a channel 1 signal and a channel 2 signal; the frequencies of the channel 1 signal and the channel 2 signal are 1001 Hz and 1002 Hz respectively. Theoretically, the difference frequency signal of the two channels is only 1 Hz, which can inhibit the activation of nerves. The square wave signal F generated by the square wave generator 221 has a duty cycle of 30% and a period of 1 s; the square wave signal is multiplied with the channel 1 signal and the channel 2 signal to obtain the channel 1 output signal and the channel 2 output signal, and the electrical stimulation signal shown in the figure is further obtained based on the channel 1 output signal and the channel 2 output signal. In addition, FIG6 is a simulation schematic diagram when the square wave truncation method is used to adjust the parameters of the electrical stimulation signal. Referring to FIG6, in the figure, (a) represents the output dual-channel sinusoidal wave signal waveform, and the frequency difference between signal 1 and signal 2 is 10HZ, (b) represents the coherent field schematic diagram of signal 1 and signal 2 in the tissue, (c) represents the output signal after the dual-channel sinusoidal wave signal waveform is truncated by a square wave signal, and (d) represents the coherent field schematic diagram of signal 1 and signal 2 in the tissue after square wave truncation. It can be understood that, under the premise that the two or more sinusoidal wave signals generated by the signal generator 211 remain unchanged, if the phase of the square wave signal output by the square wave generator 221 is changed, the output signal of each signal channel can be adjusted accordingly, thereby changing the duty cycle of the electrical stimulation signal.

In summary, when adjusting the parameters of the electrical stimulation signal based on the square wave truncation method, first determine the parameters of the required electrical stimulation signal (such as base frequency 1kHz, 1Hz coherent electric field, 30% duty cycle, dual channels, and noise of 0); then generate two or more sinusoidal wave signals of different frequencies based on the signal generator 211. Taking the generation of two sinusoidal wave signals as an example, the frequencies of the two sinusoidal waves are 1kHz and 1.001kHz respectively. Then, the single-chip microcomputer 110 controls the square wave generator 221 to generate a square wave signal with a frequency of 1Hz, a duty cycle of 30%, and an amplitude of 0-1; further, the square wave signal is multiplied with the sinusoidal wave signals of each channel for output; determine whether the final coherent signal is consistent with the required coherent signal; if not, further adjust the phase of the square wave signal output by the square wave generator 221 through the single-chip microcomputer 110 until the final output coherent signal meets the requirements. In addition, when the phase of the square wave signal is adjusted, the simulated waveform of the coherent signal can be observed according to the human-computer interaction interface in the human-computer interaction platform.

In another embodiment, the signal generator 211 may be a DDS function arbitrary waveform signal generator. In this embodiment, the DDS function arbitrary waveform signal generator is connected to the single-chip microcomputer 110 of the signal control module 100. Then, based on the single-chip microcomputer 110, the DDS function arbitrary waveform signal generator can be controlled to directly generate a signal after the square wave is truncated, that is, the DDS function arbitrary waveform signal generator can be controlled by the single-chip microcomputer 110 to directly generate the required waveform. The method of adjusting the parameters of the electrical stimulation signal in this embodiment can also be called a custom pulse synthesis method. For example, the model of the control DDS function arbitrary waveform signal generator used can be Feiyi China FY6300.

For the above-mentioned system that uses the square wave truncation method or the custom pulse synthesis method to adjust the parameters of the electrical stimulation signal, it mainly adjusts the pulse width, pulse signal-to-noise ratio, pulse repetition frequency, pulse duty cycle and other parameters of the electrical stimulation signal based on the principle of square wave truncation; in addition, in the tunable multi-frequency coupled deep tissue electrical stimulation system of other embodiments, the multi-frequency coupling method can also be used to adjust the parameters of the electrical stimulation signal. The multi-frequency coupling method achieves the tuning of the electrical stimulation signal parameters under multi-frequency coupling by adjusting the amplitude and phase of each channel signal, expanding the application scope of TI.

Exemplarily, the adjustment of the parameters of the electrical stimulation signal based on the multi-frequency coupling method specifically includes: obtaining the phase of the current signal output by each of the signal channels, and selecting the phase of the current signal output by one of the signal channels as the reference phase; calculating the phase difference between the phase of the current signal output by other channels and the reference phase; determining the target phase of the target signal output by each of the signal channels based on the frequency of the target signal output by each of the signal channels; the single-chip microcomputer 110 controls the signal of each channel output by the signal generator 211 based on the determined target phase of each of the signal channels and each of the phase differences. Further, the calculation formula of the target phase is: Φ＝A+Bf+Cf ² +Df ³ +…; wherein Φ represents the target phase, A, B, C, and D are coefficients, and f is the frequency of the target signal output by the signal channel.

Exemplarily, taking a system with five signal channels as an example, first determine that the frequencies of the signals output by the five signal channels are 1000Hz, 1001Hz, 1002Hz, 1003Hz, and 1004Hz, respectively. At this time, the current signals output by each signal channel are collected in real time, and the phases of each current signal are determined. One of the signals is selected as a reference, and the phase differences between the signal phases of other channels and the phase of the signal used as the reference are further calculated. For example, the selected reference phase is the phase of the signal corresponding to a frequency of 1000Hz. If the reference phase is 0, four phase differences are calculated at this time. In order to ensure the synchronous output of the five signals, the phases of each signal are adjusted based on the phase difference in subsequent steps. Exemplarily, when calculating the phase difference between two signals, first take the two signals as S1 and S2, and represent the two signals in complex numbers. Further cross-correlating the two signals S1 and S2 yields:

Calculating the phase angle of R(0) gives the phase difference between S1 and S2. Where T represents the total time length of the signal, represents the initial phase of the S1 signal, represents the initial phase of the S2 signal, _f1 represents the frequency of the S1 signal, _f2 represents the frequency of the S2 signal, τ represents the non-overlapping part of the S1 signal and the S2 signal, and ∑ represents the summation over time t.

Furthermore, the target phase of each signal channel is calculated according to the target phase function Φ=A+Bf+Cf ² +Df ³ +…, and the target phase function is a Taylor expansion of the frequency. Specifically, A is a constant phase, and since each signal is output synchronously, the value of A is zero; B is a first-order phase, which is equivalent to a time domain shift of the signal, and no matter what value B takes, it has no effect on the result; C is a second-order phase coefficient, also called linear chirp, and D is a third-order phase coefficient or quadratic chirp. For this target phase function, the pulse width can be changed by adjusting high-order phase coefficients such as C and D. Therefore, in actual calculations, the coefficients C and D can be determined first according to the pulse width of the signal to be output.

In the above embodiment, the frequency of the multi-channel signal output by the signal generator 211 is greater than 1kHz, and the frequency interval of each channel signal is constant, and electrical stimulation is performed through the coherent electric field generated by the multi-channel signal in the biological tissue. That is, in this method, the parameters of the electrical stimulation signal are adjusted by changing the frequency, phase, and amplitude of each channel signal. Specifically: the pulse repetition frequency of the electrical stimulation signal can be adjusted by adjusting the interval of the frequency of each channel signal; the pulse width and signal-to-noise ratio of the electrical stimulation signal can be adjusted by adjusting the phase of each channel signal; the size of the electrical stimulation signal can be adjusted by adjusting the amplitude of each channel signal; and the signal-to-noise ratio of the electrical stimulation signal can be improved by increasing the number of channels.

In addition, in the multi-frequency coupling method, the existence of high-order phases will cause many wavelets to appear in the superimposed waveform, which can be further removed by combining the square wave segmentation method. That is, the combination of the multi-frequency coupling method and the method truncation method can better achieve the adjustment of the electrical stimulation signal parameters.

FIG4 is a schematic diagram of a signal waveform of an embodiment of the present invention using a multi-frequency coupling method to adjust the parameters of an electrical stimulation signal. In this embodiment, the signal generator 211 generates five sinusoidal wave signals, such as channel 1 signal, channel 2 signal, channel 3 signal, channel 4 signal and channel 5 signal. At this time, the electrical stimulation signal obtained after coherent superposition is composed of a main envelope and four symmetrically distributed small envelopes. Since the main envelope formed after the coherent superposition of the five channels is narrow, the main envelope width (pulse width) can be changed by adjusting the phase of the output signal of each signal channel. In addition, after adjusting the main envelope width, the square wave truncation method can be further combined to complete the interception of signals of any length. The simulation schematic diagram of adjusting the parameters of the electrical stimulation signal by the multi-frequency coupling method is shown in Figure 7, wherein (a) is a waveform simulation diagram of a five-channel signal (signal 1, signal 2, signal 3, signal 4, signal 5, the frequency difference of each signal is 10 Hz, and the fundamental frequency is 1000 Hz), (b) is a schematic diagram of the coherent field of the five-channel signal in the tissue, (c) is a schematic diagram of the coherent signal after the five-channel signal is added with a second-order phase, wherein the second-order phase coefficient is pi/1000, (d) is a schematic diagram of the coherent field of the five-channel signal in the tissue after square wave truncation, and (e) is a schematic diagram of the coherent field of the five-channel signal in the tissue after being truncated after adding the second-order phase.

Through the above embodiments, it can be found that the tunable multi-frequency coupled deep tissue electrical stimulation system of the present application adopts multi-frequency coupling, and by adjusting the phase and amplitude of each signal, combined with the signal generator 211 and/or the square wave generator 221, it can achieve precise stimulation and parameter adjustment of the deep tissue target area, and realize neural activation (≥10Hz) and inhibition (1Hz). Specifically, it adjusts the amplitude and phase of the square wave signal or the sine wave signal to adjust the duty cycle, pulse width and amplitude of the electrical stimulation signal.

In the above embodiment, the signal control module 100 exchanges data with the signal generation module 200 and the signal channel module 300 through the serial port interaction protocol, that is, the signal control module 100 configures the parameters of each module according to the parameters of the output signals of each channel configured by the user, and displays the sine wave signal, square wave signal and output signal in real time, and simulates the electrical stimulation signal according to the output signal of each channel; exemplarily, the output signal frequency range of each channel is set to 100-10KHz, the maximum amplitude range is set to 0.5-50mA, the duration is at least greater than 1h, the phase shift range of each channel is 2π, and the accuracy is 2π/1024.

Correspondingly, the present invention also provides a tunable multi-frequency coupled deep tissue electrical stimulation method, and the tunable multi-frequency coupled deep tissue electrical stimulation method is implemented by the tunable multi-frequency coupled deep tissue electrical stimulation system described in any of the above embodiments.

The tunable multi-frequency coupled deep tissue electrical stimulation method can specifically adjust the parameters of the electrical stimulation signal through three methods, such as the square wave truncation method, the custom pulse synthesis method, and the multi-frequency coupling method. The square wave truncation method truncates the required part of the square wave signal by setting the square wave signal; the custom pulse synthesis method directly generates a signal similar to the truncated part of the square wave through the DDS function arbitrary waveform signal generator. The multi-frequency coupling method can further include the following two methods: one is that multiple channels generate sine waves with fixed frequency differences respectively, and short pulses are realized by superposition of sine waves; the other is that on the basis of the sine waves generated by multiple channels, the phase is adjusted to achieve tuning of the amplitude, width and other parameters of the superimposed signal; in addition, the multi-frequency coupling method can also be combined with the square wave truncation method, that is, the square wave truncation method is used to effectively remove the influence of clutter. The square wave truncation method and the custom pulse synthesis method solve the problem of tuning the parameters of the electrical stimulation signal in the existing dual-frequency coupling mode, and the multi-frequency coupling method solves the problems of too low signal-to-noise ratio and too strong channel current during TI stimulation.

In addition, the invention also discloses a computer-readable storage medium on which a computer program is stored, and when the program is executed by a processor, the steps of the method described in any of the above embodiments are implemented.

It should be understood by those skilled in the art that the exemplary components, systems and methods described in conjunction with the embodiments disclosed herein can be implemented in hardware, software or a combination of the two. Whether it is performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention. When implemented in hardware, it can be, for example, an electronic circuit, an application-specific integrated circuit (ASIC), appropriate firmware, a plug-in, a function card, etc. When implemented in software, the elements of the present invention are programs or code segments used to perform the required tasks. The program or code segment can be stored in a machine-readable medium or transmitted on a transmission medium or a communication link via a data signal carried in a carrier. "Machine-readable medium" can include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROM, flash memory, erasable ROM (EROM), floppy disks, CD-ROMs, optical disks, hard disks, optical fiber media, radio frequency (RF) links, and the like. The code segment can be downloaded via a computer network such as the Internet, an intranet, etc.

It should also be noted that the exemplary embodiments mentioned in the present invention describe some methods or systems based on a series of steps or devices. However, the present invention is not limited to the order of the above steps, that is, the steps can be performed in the order mentioned in the embodiments, or in a different order from the embodiments, or several steps can be performed simultaneously.

In the present invention, features described and/or illustrated for one embodiment may be used in the same or similar manner in one or more other embodiments, and/or combined with features of other embodiments or replace features of other embodiments.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the embodiments of the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims (3)

1. A tunable multi-frequency coupled deep tissue electrical stimulation system, characterized in that the system comprises: The signal control module includes a single chip microcomputer; the single chip microcomputer controls the signals of each channel output by the signal generator to adjust the parameters of the electrical stimulation signal, including: Obtain the phase of the current signal output by each signal channel, and select the phase of the current signal output by one of the signal channels as the reference phase; Calculating the phase difference between the phase of the current signal output by other channels and the reference phase; Determining a target phase of a target signal output by each signal channel based on the frequency of the target signal output by each signal channel; The single chip microcomputer controls the signal of each channel output by the signal generator based on the determined target phase of each signal channel and each phase difference; The calculation formula of the target phase is: in, represents the target phase, A, B, C, and D are coefficients, is the frequency of the target signal output by the signal channel, and the calculation formula of the target phase is Taylor expansion of the frequency; A signal generating module, comprising a signal generator and a first low-pass filter, wherein the input end of the signal generator is connected to the output end of the single-chip microcomputer, the single-chip microcomputer controls the signals of each channel output by the signal generator to adjust the parameters of the electrical stimulation signal, and the input end of the first low-pass filter is connected to the output end of the signal generator; the signal generating module also comprises a square wave generator, the input end of the square wave generator is connected to the output end of the single-chip microcomputer, so that the single-chip microcomputer controls the square wave signal output by the square wave generator, and the square wave signal output by the square wave generator is used to perform square wave truncation on the signal output by the signal generator; A signal channel module, comprising a plurality of signal channels, each of the signal channels comprising a phase shifter and a voltage-current converter, the phase shifter of each of the signal channels being connected to the output end of the first low-pass filter and the single-chip microcomputer, each of the phase shifters adjusting the phase of the output signal of each of the signal channels based on a control signal received from the single-chip microcomputer, the input end of each of the voltage-current converters being connected to the output end of each of the phase shifters, and the output end of each of the voltage-current converters being used to be connected to electrodes attached to the body surface; The signal generating module also includes a second low-pass filter, the input end of the second low-pass filter is connected to the output end of the square wave generator; each of the signal channels also includes a multiplier, the multiplier is located between the phase shifter and the voltage-current converter, the input end of the multiplier is connected to the output end of the phase shifter of the channel to which it belongs and the output end of the second low-pass filter, and the output end of the multiplier is connected to the input end of the voltage-current converter. 2. The tunable multi-frequency coupled deep tissue electrical stimulation system according to claim 1, characterized in that the signal generator is a DDS function arbitrary waveform signal generator. 3. The tunable multi-frequency coupled deep tissue electrical stimulation system according to claim 1 is characterized in that the signal control module also includes a human-computer interaction platform, and the human-computer interaction platform is connected to the single-chip microcomputer.