Interference elimination method, medium and device

Abstract

The present application relates to the field of signal processing, and discloses an interference elimination method, medium and device, which can eliminate interference signals from measurement signals received based on multiple channels to obtain effective signals, so as to avoid the influence of interference signals on effective signals. The method includes: collecting a measurement signal mixed with an effective signal and a first interference signal from a first channel, and collecting a second interference signal from a second channel; estimating the first interference signal in the measurement signal based on the coupling relationship between the first calibration data and the second calibration data, and based on the second interference signal; removing the first interference signal from the measurement signal to obtain a target effective signal; wherein the first calibration data and the second calibration data are interference signals respectively collected from the first channel and the second channel when the electronic device is in a preset state. The method can be specifically used in a scenario where the influence of electromagnetic interference signals on magnetic resonance imaging signals is eliminated.

Description

Technical Field

[0001] The present application relates to the field of signal processing technology, and in particular to an interference elimination method, medium and device. Background Art

[0002] With the extensive application of electrical and electronic equipment, people have higher and higher requirements for the quality of signals received by electronic equipment. Usually, there is interference in the environment where the electronic equipment is located, and the operation process of the electronic equipment and the feeder system will also cause interference, which makes the effective signal received by the electronic equipment affected by other interference signals. In other words, the interference signal will damage the reception of the effective signal, thereby causing the effective signal obtained by the electronic device to be distorted or the signal-to-noise ratio (SNR) to be reduced.

[0003] For example, for Magnetic Resonance Imaging (MRI) equipment, the collected MRI signals are usually affected by interference signals such as electromagnetic interference (EMI) in the environment, which may cause artifacts in the MRI or reduce the signal-to-noise ratio of the MRI, thereby reducing the accuracy of the MRI. In order to avoid the influence of electromagnetic interference signals on the quality of MRI, it is usually necessary to strictly electromagnetically shield the MRI equipment, such as placing the MRI equipment in a specific room, and electromagnetic shielding will greatly limit the application scenarios of MRI. Summary of the invention

[0004] The embodiments of the present application provide an interference elimination method, medium and device, which can eliminate interference signals from measurement signals received based on multiple channels to obtain valid signals, so as to avoid the influence of interference signals on valid signals.

[0005] In the first aspect, the embodiment of the present application provides an interference elimination method, which is applied to an electronic device including a first channel and a second channel with a signal receiving function, including: collecting a measurement signal mixed with an effective signal and a first interference signal from the first channel, and collecting a second interference signal from the second channel; according to the coupling relationship between the first calibration data and the second calibration data, and based on the second interference signal, estimating the first interference signal in the measurement signal; removing the first interference signal from the measurement signal to obtain a target effective signal; wherein the first calibration data and the second calibration data are interference signals collected from the first channel and the second channel respectively when the electronic device is in a preset state. As an example, the above method can be applied to scenes such as magnetic resonance imaging, synchronous EEG functional magnetic resonance imaging, and speech signal processing, but is not limited thereto. For example, the above first channel can be used to receive effective signals, and to receive or sense interference signals; and the second channel can be used only to receive interference signals. The above first calibration data and the second calibration data only contain interference signals, that is, relatively pure interference signals. Thus, the first calibration data and the second calibration data can be used to estimate the coupling relationship between the first channel and the second channel of the interference signal, and then, the interference signal in the actual measurement signal can be estimated and removed based on the coupling relationship to eliminate the influence of the interference signal on the effective signal. For example, in a magnetic resonance imaging scenario, the measurement signal includes a mixed magnetic resonance imaging signal and an electromagnetic interference signal, for example, the first calibration data and the second calibration data can be calibration data 1 and calibration data 2 respectively described below; the effective signal and the first interference signal in the measurement signal can be the magnetic resonance imaging signal and the electromagnetic interference signal 1 described below respectively; and the second interference signal can be the electromagnetic interference signal 2 described below. Specifically, in a magnetic resonance imaging scenario, the electromagnetic interference signal in the measurement signal can be estimated and removed according to the above interference elimination method to eliminate the influence of the electromagnetic interference signal on the magnetic resonance imaging signal. Furthermore, the artifacts existing in magnetic resonance imaging can be eliminated, the quality of magnetic resonance imaging can be improved, and the normal operation of the low-field magnetic resonance imaging device in an unshielded or partially shielded environment can be achieved.

[0006] In a possible implementation of the first aspect, the coupling relationship is used to represent the frequency domain correlation between the interference signal in the first channel and the second channel, and the coupling relationship is continuous and smooth in the frequency domain. For example, the coupling relationship can be represented by a coupling function related to the frequency domain, and the coupling function can refer to the coupling function F below.

[0007] In a possible implementation of the first aspect, the method further includes: according to the formula The coefficient c is obtained by the first calibration data and the second calibration data i,j , coefficient c i,jUsed to express the coupling relationship, and the coefficient c i,j is the time-invariant convolution kernel coefficient; where the size of the convolution kernel is 2K+1, that is, the size of the convolution kernel is an odd number, K is a natural number, and s r,t is the tth sample data from the rth first-category channel in the first calibration data, s i,j is the jth sampled data from the i-th second-category channel in the second calibration data, the electronic device includes M second-category channels and N first-category channels, i is a positive integer from 1 to M, and r is a positive integer from 1 to N. For example, the size (also called the size) of the convolution kernel can be used to represent the product of the number of rows and the number of columns of the matrix corresponding to the convolution kernel.

[0008] In a possible implementation of the first aspect, the formula (i.e., formula (1) below) and the first calibration data and the second calibration data to obtain the coefficient c i,j , including: According to the formula For each sampled data from the rth first-category channel in the first calibration data, an equation with the convolution kernel coefficient as the unknown is obtained, and the equations corresponding to all the sampled data of the r first-category channels are combined to obtain a linear equation system, and the coefficient c is obtained by solving the linear equation system. i,j .

[0009] In a possible implementation of the first aspect, estimating the first interference signal in the measurement signal based on the coupling relationship between the first calibration data and the second calibration data and based on the second interference signal includes: estimating the first interference signal in the measurement signal based on the formula (i.e., formula (2) below) and coefficient c i,j and the first interference signal, and estimate the second interference signal; wherein, s′ r,r is the tth sample data from the rth first-category channel in the second interference signal, s′ i,j is the jth sampled data from the i-th second-category channel in the first interference signal. It can be understood that the coupling relationship between the second interference signal and the first interference signal in each channel is consistent with the coupling relationship between the first calibration data and the second calibration data in each channel. Therefore, formula (1) and formula (2) have the same coefficient c i,j .

[0010] In a possible implementation of the first aspect above, the electronic device is a magnetic resonance imaging device, the effective signal is a magnetic resonance imaging signal, and the interference signal includes at least one of an electromagnetic interference signal and thermal noise; the first type of channel (i.e., the receiving coil channel hereinafter) is implemented by one or more phased array coils; the second type of channel (i.e., the induction coil channel hereinafter) is implemented by one or more phased array coils, or one or more electrodes attached to the surface of the detection object (such as human skin).

[0011] In a possible implementation of the first aspect above, the electronic device is a synchronous EEG-functional magnetic resonance imaging device, the effective signal is an EEG signal, and the interference signal includes at least one of a radio frequency signal and a gradient signal generated by the magnetic resonance imaging device; the first type of channel is realized by one or more electrodes attached to the surface of the detection object (such as the human brain); the second type of channel is realized by one or more electrodes attached to the surface of the detection object (such as the scalp or the human body), or one or more phased array coils (such as the induction coil mentioned below).

[0012] In a possible implementation of the first aspect, the electronic device is a magnetic resonance imaging device including a transmitting coil, and the preset state is to turn off the transmitting coil; the method further includes: in the preset state, the signal collected from the first channel is used as the first calibration data, and the signal collected from the second channel is used as the second calibration data; wherein the radio frequency signal emitted by the transmitting coil is used to stimulate the first channel to receive a valid signal. The radio frequency signal emitted by the transmitting coil is used to stimulate the receiving coil channel to receive a magnetic resonance imaging signal, and the measurement signal is mainly dominated by electromagnetic interference. When the transmitting radio frequency coil is turned off, the transmitting radio frequency coil will not generate a magnetic resonance imaging signal, so at this time, the signals in the first channel and the second channel are only electromagnetic interference signals.

[0013] In a possible implementation of the first aspect, the preset state is that the signals in the first channel and the second channel are collected multiple times; the method further includes: in the preset state, the first signal is used as the first calibration data, and the second signal is used as the second calibration data; wherein the first signal is the difference between the signals collected from the first channel twice in a row, and the second signal is the difference between the signals collected from the second channel twice in a row in the first interference signal. It can be understood that for low-field magnetic resonance imaging equipment, magnetic resonance signals can be collected multiple times to improve the signal-to-noise ratio. Specifically, for signals collected multiple times by a magnetic resonance imaging device, it can be considered that the magnetic resonance signals collected twice in close proximity are theoretically unchanged, while the electromagnetic interference signal changes randomly; by subtracting two close acquisitions, the electromagnetic interference signal can be retained as calibration data, while the magnetic resonance signal can be eliminated to the greatest extent.

[0014] In a possible implementation of the first aspect, the electronic device is a magnetic resonance imaging device including a gradient coil, and the preset state is a dead time during acquisition of a measurement signal and a second interference signal; when in the preset state, a damaged gradient from the gradient coil is used to destroy a valid signal, and a signal collected from a first channel is used as first calibration data, and a signal collected from a second channel is used as second calibration data; wherein the dead time is the time used to wait for the transverse or longitudinal magnetization vector to recover to an original state when the magnetic resonance imaging device performs magnetic resonance imaging.

[0015] In a possible implementation of the first aspect above, the electronic device is a magnetic resonance imaging device including a transmitting coil, and a preset state is that the high-frequency part signal in the frequency domain space (i.e., k-space) of the signal collected from the first channel and the second channel is dominated by electromagnetic interference; the method also includes: using the high-frequency part signal in the frequency domain space of the measurement signal as the first calibration data, and using the high-frequency part signal in the frequency domain space of the second interference signal as the second calibration data.

[0016] In a possible implementation of the first aspect, the effective signal and the interference signal are both one-dimensional or multi-dimensional data, the convolution kernel is a one-dimensional or multi-dimensional convolution kernel, and the dimension of the signal is consistent with the dimension of the convolution kernel.

[0017] In the second aspect, the embodiment of the present application provides an interference elimination device, which is applied to an electronic device including a first channel and a second channel with a signal receiving function, including: an acquisition module, which is used to acquire a measurement signal mixed with a valid signal and a first interference signal from the first channel, and to acquire a second interference signal from the second channel; an estimation module, which is used to estimate the first interference signal in the measurement signal based on the coupling relationship between the first calibration data and the second calibration data, and based on the acquired second interference signal; a removal module, which is used to remove the first interference signal from the measurement signal to obtain a target valid signal; wherein the first calibration data and the second calibration data are interference signals respectively acquired from the first channel and the second channel when the electronic device is in a preset state. For example, the above-mentioned acquisition module, estimation module and removal module can be implemented by a processor having the functions of these modules or units in the electronic device.

[0018] In a possible implementation of the second aspect, the coupling relationship is used to represent the frequency domain correlation of the interference signal in the first channel and the second channel, and the coupling relationship is continuous and smooth in the frequency domain.

[0019] In a possible implementation of the second aspect, the apparatus further includes: a determination module configured to determine, according to the formula The coefficient c is obtained by the first calibration data and the second calibration data i,j , coefficient ci,j Used to express the coupling relationship, and the coefficient c i,j is the time-invariant convolution kernel coefficient; where the size of the convolution kernel is 2K+1, K is a natural number, and s r,t is the tth sample data from the rth first-category channel in the first calibration data, s i,j is the jth sampled data from the i-th second-category channel in the second calibration data, the electronic device includes M second-category channels and N first-category channels, i is sequentially a positive integer from 1 to M, and r is sequentially a positive integer from 1 to N. For example, the above determination may be implemented by a processor having the function of the module or unit in the electronic device.

[0020] In a possible implementation of the second aspect, the determination module is specifically configured to determine the following: For each sampled data from the rth first-category channel in the first calibration data, an equation with the convolution kernel coefficient as the unknown is obtained, and the equations corresponding to all the sampled data of the r first-category channels are combined to obtain a linear equation system, and the coefficient c is obtained by solving the linear equation system. i,j .

[0021] In a possible implementation of the second aspect, estimating the first interference signal in the measurement signal based on the coupling relationship between the first calibration data and the second calibration data and based on the second interference signal includes: estimating the first interference signal in the measurement signal based on the formula and the coefficient c i,j and the first interference signal, and estimate the second interference signal; wherein, s′ r,t is the tth sample data from the rth first-category channel in the second interference signal, s′ i,j is the j-th sampling data from the i-th second-category channel in the first interference signal.

[0022] In a possible implementation of the second aspect, the electronic device is a magnetic resonance imaging device, the effective signal is a magnetic resonance imaging signal, and the interference signal includes at least one of an electromagnetic interference signal and thermal noise; the first type of channel is implemented by one or more phased array coils; and the second type of channel is implemented by one or more phased array coils, or one or more electrodes attached to the surface of the detection object.

[0023] In a possible implementation of the second aspect above, the electronic device is a synchronous EEG-functional magnetic resonance imaging device, the effective signal is an EEG signal, and the interference signal includes at least one of a radio frequency signal and a gradient signal generated by the magnetic resonance imaging device; the first type of channel is realized by one or more electrodes attached to the surface of the detection object; the second type of channel is realized by one or more electrodes attached to the surface of the detection object, or one or more phased array coils.

[0024] In a possible implementation of the second aspect, the electronic device is a magnetic resonance imaging device including a transmitting coil, and the preset state is to turn off the transmitting coil; the device further includes: when in the preset state, using a signal collected from a first type of channel as first calibration data, and using a signal collected from a second type of channel as second calibration data; wherein the radio frequency signal emitted by the transmitting coil is used to excite the first type of channel to receive a valid signal.

[0025] In a possible implementation of the second aspect above, the preset state is that the signals in the first category channel and the second category channel are collected multiple times; the above device also includes: when in the preset state, the first signal is used as the first calibration data, and the second signal is used as the second calibration data; wherein the first signal is the difference between the signals collected from the first category channel twice in a row, and the second signal is the difference between the signals collected from the second category channel twice in a row in the first interference signal.

[0026] In a possible implementation of the second aspect, the electronic device is a magnetic resonance imaging device including a gradient coil, and the preset state is a dead time during acquisition of a measurement signal and a second interference signal; when in the preset state, a damaged gradient from the gradient coil is used to destroy the effective signal, and the signal collected from the first channel is used as the first calibration data, and the signal collected from the second channel is used as the second calibration data; wherein the dead time is the time used to wait for the transverse or longitudinal magnetization vector to recover to an original state when the magnetic resonance imaging device performs magnetic resonance imaging.

[0027] In a possible implementation of the second aspect above, the electronic device is a magnetic resonance imaging device including a transmitting coil, and a preset state is that the high-frequency part signal in the frequency domain space of the signal collected from the first channel and the second channel is dominated by electromagnetic interference; the device also includes: using the high-frequency part signal in the frequency domain space of the measurement signal as the first calibration data, and using the high-frequency part signal in the frequency domain space of the second interference signal as the second calibration data.

[0028] In a possible implementation of the second aspect, the effective signal and the interference signal are both one-dimensional or multi-dimensional data, the convolution kernel is a one-dimensional or multi-dimensional convolution kernel, and the dimension of the signal is consistent with the dimension of the convolution kernel.

[0029] In a third aspect, an embodiment of the present application provides a computer-readable storage medium, on which instructions are stored. When the instructions are executed on a computer, the computer executes the interference elimination method in the first aspect.

[0030] In a fourth aspect, an embodiment of the present application provides an electronic device, comprising: one or more processors; one or more memories; the one or more memories storing one or more programs, and when the one or more programs are executed by the one or more processors, the electronic device executes the interference elimination method in the above-mentioned first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 According to some embodiments of the present application, a schematic structural diagram of a magnetic resonance imaging device is shown;

[0032] Figure 2 According to some embodiments of the present application, a schematic flow chart of an interference elimination method is shown;

[0033] Figure 3 According to some embodiments of the present application, a schematic diagram of a convolution kernel is shown;

[0034] Figure 4 According to some embodiments of the present application, a block diagram of a computer of a magnetic resonance imaging device is shown;

[0035] Figure 5 According to some embodiments of the present application, a block diagram of a mobile phone is shown. DETAILED DESCRIPTION

[0036] Illustrative embodiments of the present application include, but are not limited to, interference cancellation methods, media, and devices.

[0037] The interference elimination method provided in the embodiment of the present application can be applied to scenarios such as magnetic resonance imaging (MRI), synchronous EEG functional magnetic resonance imaging, and speech signal processing, but is not limited thereto. Specifically, the electronic device may include multiple channels with a signal receiving function to eliminate interference signals from the measurement signals of the multiple channels, thereby obtaining effective signals that are not affected by the interference signals, such as magnetic resonance imaging signals, EEG signals, speech signals, etc. in the aforementioned applications.

[0038] As an example, in a magnetic resonance imaging scenario, the effective signal may be a magnetic resonance imaging signal, and the interference signal may be thermal noise or an electromagnetic interference signal (EMI) in the environment, etc. At this time, the electronic device may be a device having a magnetic resonance imaging function, which is referred to as a magnetic resonance imaging device in this article.

[0039] As another example, in a synchronous EEG functional magnetic resonance imaging scenario, the effective signal may be an EEG signal, and the interference signal may include a magnetic resonance imaging radio frequency signal and a gradient signal generated during the operation of the electronic device. In this case, the electronic device may be a device with synchronous EEG functional magnetic resonance imaging, which may be referred to as an EEG imaging device in this article.

[0040] As another example, in a speech signal processing scenario, the effective signal may be a speech signal to be processed, and the interference signal may be environmental noise, etc. At this time, the electronic device may be an electronic device with a speech processing function, such as an electronic device with a voice assistant software installed. As an example, the electronic devices in this scenario may include, but are not limited to: mobile phones, smart speakers, tablet computers, laptop computers, desktop computers, ultra-mobile personal computers (UMPC), netbooks, as well as cellular phones, personal digital assistants (PDA), augmented reality (AR), virtual reality (VR) devices, etc.

[0041] In the following embodiments, the interference elimination method provided by the embodiments of the present application is mainly described by taking the magnetic resonance imaging device performing the interference elimination method in the magnetic resonance imaging scenario as an example. Similarly, the implementation details of the electronic device performing the interference elimination method in other application scenarios will not be described one by one in this document, and some descriptions can refer to the relevant description of the magnetic resonance imaging device performing the interference elimination method.

[0042] Magnetic resonance imaging technology can generate medical images in medical or clinical application scenarios for disease diagnosis. Specifically, magnetic resonance imaging technology can use the signals generated by the resonance of atomic nuclei in a strong magnetic field to reconstruct images and make cross-sectional, sagittal, coronal and various oblique plane tomographic images of objects such as the human body.

[0043] In the implementation of this application, the magnetic resonance imaging device can be a low-field or ultra-low-field magnetic resonance imaging device, or a medium-field or high-field magnetic resonance imaging device. As an example, the magnetic resonance imaging system in clinical applications can usually be divided into high field (above 1T), medium field (0.3-1T), low field (0.1-0.3T), and ultra-low field (below 0.1T) according to the magnetic field strength.

[0044] It is understandable that MRI equipment usually needs to be deployed in a specific room or area in a hospital or research institution to achieve strict electromagnetic shielding. It is a large-scale equipment with high cost and complex structure, and cannot be used as a general imaging equipment due to the limited use site. The small-scale MRI equipment that is not limited to the deployment site, such as not limited to use in hospitals or research institutions, and is mobile and low-cost will greatly expand the application scenarios of MRI.

[0045] More specifically, the embodiments of the present application are mainly applied to low-field or ultra-low-field magnetic resonance imaging equipment, and eliminate interference signals such as environmental electromagnetic interference signals during magnetic resonance imaging, thereby eliminating artifacts present in magnetic resonance imaging, improving the quality of magnetic resonance imaging, and realizing normal operation of low-field magnetic resonance imaging equipment in an unshielded or partially shielded environment. In this way, since the magnetic resonance imaging equipment does not require strict electromagnetic shielding, that is, the magnetic resonance imaging equipment does not need to be placed in a shielded room, there is no need to build a special shielded room, and the installation is simple, which can greatly reduce costs. In addition, the application scenarios of magnetic resonance imaging can be greatly expanded, for example, it can be applied to bedside magnetic resonance imaging (Point-Of-Care MRI, POC MRI), emergency room (ICU) or medical vehicles and ambulances.

[0046] According to some embodiments of the present application, one or more multi-channel coils commonly used in magnetic resonance parallel imaging (such as phased array coils), or one or more electrodes that can be attached to the surface of human skin can be used to receive signals. Functionally, the above coils or electrodes can be divided into two categories. One type of coil, called a receiving coil, is used to receive magnetic resonance signals (specifically magnetic resonance imaging signals), and should avoid receiving interference signals such as electromagnetic interference signals or thermal noise in the environment. Specifically, in actual application, due to the lack of electromagnetic shielding in low-field magnetic resonance imaging equipment, the receiving coil will inevitably be affected by electromagnetic interference, that is, the receiving coil will also receive some electromagnetic interference signals, etc. The other coil, called a sensing coil, is used to sense environmental electromagnetic interference signals, and this function can also be achieved with electrodes.

[0047] The embodiments of the present application will be described in further detail below in conjunction with the accompanying drawings.

[0048] like Figure 1, which is a possible structural schematic diagram of a magnetic resonance imaging device provided in an embodiment of the present application. The magnetic resonance imaging device 100 may include: a computer 101, a spectrometer 102, a gradient amplifier 103, a gradient coil 104, a transmitting radio frequency amplifier 105, a transmitting radio frequency coil (also called a transmitting coil) 106, a receiving radio frequency coil 107, a receiving radio frequency amplifier (also called a receiving coil) 108, a magnet 109, an induction coil 101, and a receiving radio frequency amplifier 110.

[0049] Specifically, the computer 101 is used to issue an instruction to the spectrometer 102 under the control of the operator to trigger the spectrometer 102 to generate the waveform of the gradient signal and the waveform of the radio frequency signal according to the instruction. After the gradient signal generated by the spectrometer 102 is amplified by the gradient amplifier 103, the gradient coil 104 forms the gradient of the magnetic field, thereby realizing the spatial gradient encoding for the magnetic resonance signal (specifically the magnetic resonance imaging signal). Specifically, the spatial gradient encoding is used to spatially locate the magnetic resonance signal, that is, to distinguish the location of the source of the magnetic resonance signal. The radio frequency signal generated by the spectrometer 102 is amplified by the transmitting radio frequency amplifier 105 and emitted by the transmitting radio frequency coil 106, thereby exciting the protons (hydrogen nuclei) in the imaging area. Among them, the excited protons can emit radio frequency signals, which can be received by the receiving coil 108, and after being amplified by the receiving radio frequency amplifier 107, they are converted into digital signals by the spectrometer 102, and then transmitted to the computer 101 for processing to obtain images and display. In addition, the magnet 109 can be any suitable type of magnet that can generate a main magnetic field. The induction coil 101 is used to sense the electromagnetic interference signal in the environment, and after being amplified by the receiving radio frequency amplifier 110, it is converted into a digital signal by the spectrometer 102 and transmitted to the computer 101 for processing.

[0050] In some embodiments, when designing the receiving coil and the induction coil, it is necessary to improve the signal-to-noise ratio that the coil can provide as much as possible. That is, for the receiving coil, it should be able to receive the magnetic resonance signal (specifically the magnetic resonance imaging signal) as sensitively as possible, and be affected as little as possible by electromagnetic interference and thermal noise. For the induction coil, it should be able to sense the environmental electromagnetic interference as sensitively as possible, receive as little magnetic resonance signal as possible, and be affected as little as possible by thermal noise.

[0051] In addition, in some embodiments, the above two types of coils need to reduce the influence of thermal noise as much as possible. For example, in practical applications, some cooling devices can be used to reduce the coil resistance to the greatest extent by cooling, thereby reducing the influence of thermal noise. It is understood that the cooling device is not specifically described in the embodiments of the present application, and any achievable method in the relevant technology can be referred to.

[0052] Similarly, the electroencephalography device in the embodiment of the present application may also include Figure 1 The transmitting coil 106 and receiving coil 108 shown are used to generate magnetic resonance imaging radio frequency signals based on the same process; a gradient coil 104 may also be included to generate gradient signals.

[0053] In some embodiments, the receiving coil and the induction coil can be implemented using a single or multiple phased array coils widely used in modern medical magnetic resonance imaging. In addition, when the scanning object is a human body, the induction coil can also be replaced by an electrode attached to the surface of the human skin, which can be used to sense the electromagnetic interference signal received by the human body, thereby eliminating the electromagnetic interference signal in the measurement signal of the receiving coil.

[0054] It is understandable that, in the embodiment of the present application, the multiple channels with signal receiving function involved in the magnetic resonance imaging device 100 may include multiple channels of a single phased array coil, or may include multiple channels of multiple coils, and the present application does not specifically limit this. In addition, in the embodiment of the present application, the design and layout (deployment position, deployment direction, etc.) of the receiving coil and the induction coil in the magnetic resonance imaging device 100 are not specifically limited, and can be any feasible solution.

[0055] More specifically, in some embodiments of the present application, for the magnetic resonance imaging device 100, the channels in the receiving coil can be referred to as receiving coil channels. The more channels the receiving coil has, the more conducive it is to improving the signal-to-noise ratio (SNR) of the magnetic resonance signal received by the receiving coil, or enabling the receiving coil to provide parallel imaging capabilities. In an embodiment of the present application, receiving coils with multiple channels can also be used to enhance their ability to identify and eliminate electromagnetic interference signals. The channels in the induction coil can be referred to as induction coil channels. The more channels the induction coil has, the more accurately it can characterize the characteristics of the electromagnetic interference signal, thereby accurately estimating the electromagnetic interference signal received by the receiving coil through the electromagnetic interference signal received by the induction coil.

[0056] For example, Figure 1 The magnetic resonance imaging device 100 shown may provide one receiving coil and one induction coil, and the receiving coil has one channel, and the induction coil has two channels, but is not limited thereto. In this case, the multiple channels provided by the magnetic resonance imaging device 100 include the receiving coil channel and the induction coil channel.

[0057] Similarly, in a synchronous EEG functional magnetic resonance imaging scenario, the multiple channels with signal receiving function provided by the EEG imaging device can be implemented by electrodes attached to the scalp. Also, in a speech signal processing scenario, the multiple channels provided by the electronic device can be multiple analog signal channels provided by multiple microphones.

[0058] In the embodiment of the present application, Figure 1 The magnetic resonance imaging device 100 shown can collect measurement signals from the receiving coil channel and the induction coil channel, and obtain calibration data from these channels. Further, the electromagnetic interference signal in the actual collected measurement signal can be estimated by convolution operation based on the calibration data to achieve electromagnetic interference elimination.

[0059] The calibration data only includes electromagnetic interference signals from the receiving coil channel and the induction coil channel of the magnetic resonance imaging device 100. That is, the calibration data is a relatively pure electromagnetic interference signal, which can be used to estimate the coupling relationship between electromagnetic interference signals received by different channels.

[0060] In some embodiments, the calibration data is an electromagnetic interference signal acquired from a receiving coil channel and an induction coil channel when the magnetic resonance imaging device 100 is in a preset state.

[0061] In some embodiments of the present application, the magnetic resonance imaging device 100 may obtain calibration data in the following ways (1) to (4):

[0062] (1) Pre-scan method:

[0063] The magnetic resonance imaging device 100 obtains measurement signals from the receiving coil channel and the induction coil channel when the transmitting coil (i.e., the above-mentioned transmitting radio frequency coil 106) is turned off, and these measurement signals are used as calibration data. Among them, the radio frequency signal emitted by the transmitting coil is used to excite the nuclei (such as hydrogen nuclei) in the imaging object, and the excited nuclei will emit magnetic resonance imaging signals, which are then received by the receiving coil channel. If the transmitting coil is turned off, the measurement signal received by the receiving coil does not contain the magnetic resonance imaging signal, but is completely composed of electromagnetic interference and thermal noise. Specifically, the magnetic resonance imaging device 100 can turn off the transmitting radio frequency coil before or after collecting the magnetic resonance imaging signal (then the receiving radio frequency coil will not receive the magnetic resonance imaging signal) to collect the above-mentioned calibration data. However, this method has two major defects. One is that it will prolong the total scanning time of the magnetic resonance imaging device 100; and if the electromagnetic interference signal in the environment changes, or the coupling relationship between the signals in each channel changes due to the movement of the scanned object (such as the human body), the calibration data will not be used to accurately estimate the coupling relationship between the electromagnetic interference signals in each channel during the formal magnetic resonance imaging scan. At this time, the preset state is that the transmitting coil 106 of the magnetic resonance imaging device 100 is turned off.

[0064] It should be noted that the coupling relationship between the electromagnetic interference signal and the multiple channels of the magnetic resonance imaging device 100 is specifically the frequency domain correlation between the electromagnetic interference signal and the multiple channels, and the coupling relationship is continuous and smooth in the frequency domain. It can be understood that the frequency domain correlation between the electromagnetic interference signal and the multiple channels can be expressed as the linear relationship between the electromagnetic interference signals received by each channel at different frequency points.

[0065] Specifically, the coupling relationship can be represented by a coupling function related to the frequency domain, and the coupling function is continuous and smooth in the frequency domain. As an example, in the embodiment of the present application, when the multiple channels of the magnetic resonance imaging device 100 include a receiving coil channel and an induction coil channel, the electromagnetic interference signal c sensed by the induction coil channel included in the calibration data can be sen , and the electromagnetic interference signal c received by the receiving coil channel rec , estimate the above coupling function F, so that F(c sen )=c rec Subsequently, when the magnetic resonance imaging device 100 formally collects signals from the receiving coil channel, the electromagnetic interference signal s sensed by the induction coil channel may be sen The electromagnetic interference signal s received by the receiving coil channel is estimated by the coupling function F rec , so that s rec =F(c sen ).

[0066] (2) Multiple acquisitions to obtain differences:

[0067] In the case where the signals in the multiple channels of the magnetic resonance imaging device 100 are collected multiple times, the difference between the signals collected from the multiple channels twice (or more times) is used as the calibration data. Specifically, the magnetic resonance imaging device 100 uses the difference between the signals collected from the receiving coil channels twice as a part of the calibration data, and uses the difference between the signals collected from the receiving coil channels twice as another part of the calibration data.

[0068] It is understandable that the low-field magnetic resonance imaging device can collect magnetic resonance signals multiple times to achieve magnetic resonance imaging. Specifically, for the signals collected multiple times by the magnetic resonance imaging device, it can be considered that the magnetic resonance signals collected twice are theoretically unchanged, while the electromagnetic interference signal changes randomly; by subtracting the two similar acquisitions, the electromagnetic interference signal can be retained as calibration data, and the magnetic resonance signal can be eliminated to the greatest extent.

[0069] However, if there is magnetic field drift (which leads to phase change), or the scanned object (or detection object) moves, or there is free induction decay (FID) signal in fast spin echo (FSE) imaging using phase cycling, these will result in the magnetic resonance signals obtained by multiple scans not being eliminated to the greatest extent, thus affecting the estimation of the above coupling relationship.

[0070] (3) Intra-scan method:

[0071] The magnetic resonance imaging device 100 uses the damaged gradient from the gradient coil to destroy the magnetic resonance imaging signal during the dead time during which the signal is actually collected from multiple channels, and obtains the measurement signal from multiple channels, and uses the measurement signal as calibration data. The dead time is the time used to wait for the transverse or longitudinal magnetization vector to return to the original state when the magnetic resonance imaging device performs magnetic resonance imaging. Specifically, the calibration data includes the measurement signal collected from the receiving coil channel and the measurement signal collected from the induction coil channel. The above-mentioned preset state can be the dead time during which the magnetic resonance imaging device 100 is in the period of collecting signals.

[0072] It is understandable that the calibration data can be collected using the dead time during the scanning process, which can avoid the problems in (1) and (2) above, but the scanning sequence needs to be modified, which will also increase the amount of data collected and increase the difficulty of subsequent calculations. Specifically, for data collection during the dead time stage, it is also necessary to turn on the gradient coil to generate a readout gradient. Before the formal data collection, it is necessary to add a crusher gradient to the gradient coil, which can minimize the component of the magnetic resonance imaging signal in the calibration data. As an example, for fast spin echo (FSE), the echo train length (ETL) can be extended. For the readout at a later time, the transmitting RF coil can be turned off (i.e., the 180-degree refocusing RF pulse is turned off) to collect the calibration data.

[0073] (4) Using the high frequency part of k-space:

[0074] The magnetic resonance imaging device 100 uses the high frequency part of the signals collected from the multiple channels in the frequency domain as calibration data. At this time, the calibration data includes the signals collected from the receiving coil channel and the signals collected from the induction coil channel.

[0075] It is understandable that the high-frequency part of the magnetic resonance imaging signal in the frequency domain space (ie, k-space) is relatively weak, and it can be considered that the signal in this part is dominated by electromagnetic interference, so this part of the data is used as calibration data.

[0076] Based on the above description, the main working process of the interference elimination method performed by the nuclear magnetic resonance imaging device 100 is specifically introduced below. Figure 1 The technical details described in the magnetic resonance imaging device 100 are still applicable in the following method flow. To avoid repetition, some will not be described again. In some embodiments, the execution subject of the interference elimination method of the present application can be the magnetic resonance imaging device 100, specifically the computer 101 in the magnetic resonance imaging device 100. Figure 2 As shown, an interference elimination method process provided by the present application may include the following steps 201 to 205:

[0077] Step 201: The magnetic resonance imaging device 100 acquires calibration data 1 from a receiving coil channel and acquires calibration data 2 from an induction coil channel.

[0078] It can be understood that the calibration data 1 and the calibration data 2 as a whole are calibration data acquired by the magnetic resonance imaging apparatus 100 from multiple channels.

[0079] Step 202: The magnetic resonance imaging device 100 acquires a measurement signal from the receiving coil channel and acquires an electromagnetic interference signal 1 from the induction coil channel.

[0080] It can be understood that the above-mentioned measurement signal and the electromagnetic interference signal 1 as a whole are the signals actually collected by the magnetic resonance imaging device 100 from multiple channels.

[0081] In some embodiments, for a low-field (or ultra-low-field) magnetic resonance imaging device 100, the measurement signal and the electromagnetic interference signal 1 are acquired multiple times from multiple channels.

[0082] Step 203: The magnetic resonance imaging device 100 uses the formula (i.e., formula (1)) and calibration data 1 and calibration data 2 to obtain coefficient c i,j , and the coefficient c i,j is the time-invariant convolution kernel coefficient.

[0083] Among them, the coefficient c i,j Used to indicate the coupling relationship between the electromagnetic interference signal in the receiving coil channel and the induction coil channel.

[0084] Among them, the coefficient c i,j The size of the corresponding convolution kernel is 2K+1, that is, the size of the convolution kernel is an odd number, K is a natural number, and s r,tis the tth sampling data from the rth receiving coil channel in calibration data 1, s i,j is the jth sampled data from the i-th induction coil channel in the calibration data 2, the magnetic resonance imaging device 100 includes M induction coil channels and N receiving coil channels, i is a positive integer from 1 to M, and r is a positive integer from 1 to N. The size (also called size) of the convolution kernel can be used to represent the product of the number of rows and the number of columns of the matrix corresponding to the convolution kernel.

[0085] For example, Figure 3 As shown, it is a schematic diagram of a convolution kernel provided in this application, Figure 3 The channels 1 to 2 are all induction coil channels provided by the induction coil, and the channel r is a receiving coil channel provided by the receiving coil. Specifically, the size of the convolution kernel is 2K+1, and the convolution kernel is a matrix of (2K+1)×M. Assuming that M=3 and K=2, the matrix size of the convolution kernel is 5×3. In addition, the sampled data corresponding to a convolution kernel in the channels 1 to 2 corresponds to the t-th sampled data in the channel r.

[0086] In some embodiments, the magnetic resonance imaging device 100 is based on the formula For each sampled data from the rth receiving coil channel in calibration data 1, an equation with the convolution kernel coefficient as the unknown is obtained, and the equations corresponding to all the sampled data of the rth receiving coil channel are combined to obtain a linear equation system, and the coefficient c is obtained by solving the linear equation system. i,j .

[0087] Step 204: The magnetic resonance imaging device 100 uses the formula (i.e., formula (2)) and coefficient c i,j and electromagnetic interference signal 1, and estimate electromagnetic interference signal 2 in the measurement signal.

[0088] Among them, s′ r,t is the tth sampled data from the rth receiving coil channel in the electromagnetic interference signal 2, s′ i,j is the j-th sampling data from the i-th induction coil channel in the electromagnetic interference signal 1.

[0089] It can be understood that the coupling relationship between the electromagnetic interference signal 2 and the electromagnetic interference signal 1 between each channel is consistent with the coupling relationship between the calibration data 1 and the calibration data 2 between each channel. Therefore, formula (1) and formula (2) have the same coefficient c i,j .

[0090] Step 205: The magnetic resonance imaging device 100 removes the electromagnetic interference signal 2 from the measurement signal to obtain a magnetic resonance imaging signal.

[0091] In this way, in the embodiment of the present application, the magnetic resonance imaging device 100 can obtain the convolution kernel from the calibration data, and estimate the electromagnetic interference signal in the receiving coil based on the electromagnetic interference signal measured by the induction coil by the convolution kernel, and eliminate it to eliminate the influence of the electromagnetic interference signal on the magnetic resonance imaging signal, thereby improving the quality of magnetic resonance imaging.

[0092] Similarly, for other scenarios in which the embodiments of the present application are applied, the electronic device can also implement the interference elimination method according to steps similar to the above steps 201-205. The difference lies in that the execution subjects are different, the sources of multiple channels are different, and the types of valid signals and interference signals are different.

[0093] In addition, in some other embodiments, the effective signal and the interference signal may also be one-dimensional data or multi-dimensional data (such as two-dimensional data). In this case, the convolution kernel used in the interference elimination method may be a one-dimensional or multi-dimensional convolution kernel, that is, the dimension of the signal is consistent with the dimension of the convolution kernel, and the other processes are similar to the relevant descriptions in the above steps 201 to 205, and will not be repeated here.

[0094] Reference now Figure 4 , which is a block diagram of a computer in a magnetic resonance imaging device 100 according to an embodiment of the present application. Figure 4 An example computer 1400 is schematically illustrated in accordance with various embodiments. In one embodiment, the system 1400 may include one or more processors 1404, a system control logic 1408 coupled to at least one of the processors 1404, a system memory 1412 coupled to the system control logic 1408, a non-volatile memory (NVM) 1416 coupled to the system control logic 1408, and a network interface 1420 coupled to the system control logic 1408.

[0095] In some embodiments, the processor 1404 may include one or more single-core or multi-core processors. In some embodiments, the processor 1404 may include any combination of general-purpose processors and special-purpose processors (e.g., graphics processors, application processors, baseband processors, etc.). In an embodiment where the computer 1400 uses an eNB (Evolved Node B, enhanced base station) 101 or a RAN (Radio Access Network, radio access network) controller 102, the processor 1404 may be configured to execute various embodiments, such as Figure 2 One or more of the multiple embodiments shown. For example, the processor 1404 can estimate the interference signal in the actual measurement signal based on the convolution operation of the calibration data from multiple channels, and then remove the interference signal in the measurement signal to obtain the final effective signal.

[0096] In some embodiments, system control logic 1408 may include any suitable interface controller to provide any suitable interface to at least one of processors 1404 and / or any suitable device or component in communication with system control logic 1408 .

[0097] In some embodiments, the system control logic 1408 may include one or more memory controllers to provide an interface to the system memory 1412. The system memory 1412 may be used to load and store data and / or instructions. In some embodiments, the memory 1412 of the system 1400 may include any suitable volatile memory, such as a suitable dynamic random access memory (DRAM).

[0098] NVM / memory 1416 may include one or more tangible, non-transitory computer-readable media for storing data and / or instructions. In some embodiments, NVM / memory 1416 may include any suitable non-volatile memory such as flash memory and / or any suitable non-volatile storage device, such as at least one of a HDD (Hard Disk Drive), a CD (Compact Disc) drive, and a DVD (Digital Versatile Disc) drive.

[0099] NVM / storage 1416 may include a portion of storage resources on the device on which system 1400 is installed, or it may be accessible by the device but not necessarily a portion of the device. For example, NVM / storage 1416 may be accessed over a network via network interface 1420.

[0100] In particular, system memory 1412 and NVM / storage 1416 may include, respectively, a temporary copy and a permanent copy of instructions 1424. Instructions 1424 may include instructions that, when executed by at least one of processors 1404, cause computer 1400 to implement the following: Figure 2 In some embodiments, instructions 1424, hardware, firmware, and / or software components thereof may additionally / alternatively be placed in system control logic 1408, network interface 1420, and / or processor 1404.

[0101] The network interface 1420 may include a transceiver for providing a radio interface for the system 1400 to communicate with any other suitable devices (such as a front-end module, an antenna, etc.) through one or more networks. In some embodiments, the network interface 1420 may be integrated with other components of the system 1400. For example, the network interface 1420 may be integrated with at least one of the processor 1404, the system memory 1412, the NVM / storage 1416, and a firmware device (not shown) having instructions. When at least one of the processors 1404 executes the instructions, the computer 1400 implements the following. Figure 2 The method shown.

[0102] The network interface 1420 may further include any suitable hardware and / or firmware to provide a multiple-input multiple-output radio interface. For example, the network interface 1420 may be a network adapter, a wireless network adapter, a telephone modem and / or a wireless modem.

[0103] In one embodiment, at least one of the processors 1404 may be packaged together with logic for one or more controllers of the system control logic 1408 to form a system in package (SiP). In one embodiment, at least one of the processors 1404 may be integrated on the same die with logic for one or more controllers of the system control logic 1408 to form a system on a chip (SoC).

[0104] The computer 1400 may further include an input / output (I / O) device 1432. The I / O device 1432 may include a user interface that enables a user to interact with the system 1400; and a peripheral component interface that enables peripheral components to interact with the computer 1400. In some embodiments, the computer 1400 further includes a sensor for determining at least one of an environmental condition and location information related to the computer 1400.

[0105] In some embodiments, the user interface may include, but is not limited to, a display (e.g., an LCD display, a touch screen display, etc.), a speaker, a microphone, one or more cameras (e.g., a still image camera and / or a video camera), a flashlight (e.g., an LED flash), and a keyboard.

[0106] In some embodiments, the peripheral component interface may include, but is not limited to, a non-volatile memory port, an audio jack, and a power interface.

[0107] In some embodiments, the sensors may include, but are not limited to, gyroscope sensors, accelerometers, proximity sensors, ambient light sensors, and positioning units. The positioning unit may also be part of or interact with the network interface 1420 to communicate with components of a positioning network (e.g., global positioning system (GPS) satellites).

[0108] Similarly, for the voice processing scenarios applied in the embodiments of the present application, in some embodiments, the electronic device that performs interference elimination in the present application is taken as a mobile phone as an example to describe the structure of the electronic device.

[0109] like Figure 5 As shown, the mobile phone 10 may include a processor 110, a power module 140, a memory 180, a mobile communication module 130, a wireless communication module 120, a sensor module 190, an audio module 150, a camera 170, an interface module 160, a button 101 and a display screen 102, etc.

[0110] It is to be understood that the structure illustrated in the embodiment of the present invention does not constitute a specific limitation on the mobile phone 10. In other embodiments of the present application, the mobile phone 10 may include more or fewer components than shown in the figure, or combine some components, or separate some components, or arrange the components differently. The components shown in the figure may be implemented in hardware, software, or a combination of software and hardware.

[0111] The processor 110 may include one or more processing units. A storage unit may be provided in the processor 110 for storing instructions and data. In some embodiments, the storage unit in the processor 110 is a cache memory 180. For example, the processor 110 may estimate the interference signal in the actual measurement signal based on the convolution operation for the calibration data from multiple channels, and then remove the interference signal in the measurement signal to obtain the final effective signal.

[0112] The power module 140 may include a power source, a power management component, etc. The power source may be a battery. The power management component is used to manage the charging of the power source and the supply of power to other modules.

[0113] The mobile communication module 130 may include but is not limited to an antenna, a power amplifier, a filter, an LNA (Low noise amplifier) ​​and the like.

[0114] The wireless communication module 120 may include an antenna, and transmit and receive electromagnetic waves via the antenna. The mobile phone 10 may communicate with a network and other devices through wireless communication technology.

[0115] In some embodiments, the mobile communication module 130 and the wireless communication module 120 of the mobile phone 10 may also be located in the same module.

[0116] The display screen 102 is used to display a human-computer interaction interface, images, videos, etc., for example, to display the speech representation semantic information corresponding to the effective signal processed by the processor 110. The display screen 102 includes a display panel.

[0117] The sensor module 190 may include a proximity light sensor, a pressure sensor, a gyro sensor, an air pressure sensor, a magnetic sensor, an acceleration sensor, a distance sensor, a fingerprint sensor, a temperature sensor, a touch sensor, an ambient light sensor, a bone conduction sensor, and the like.

[0118] The audio module 150 is used to convert digital audio information into analog audio signal output, or convert analog audio input into digital audio signal. The audio module 150 can also be used to encode and decode audio signals. In some embodiments, the audio module 150 can be arranged in the processor 110, or some functional modules of the audio module 150 can be arranged in the processor 110. In some embodiments, the audio module 150 can include a speaker, an earpiece, a microphone, and an earphone interface. For example, a microphone can be used to provide multiple channels for obtaining calibration data or collecting measurement signals.

[0119] In some embodiments, the mobile phone 10 further includes a button 101, a motor, an indicator, etc. Among them, the button 101 may include a volume button, a power on / off button, etc.

[0120] The various embodiments of the mechanism disclosed in the present application can be implemented in hardware, software, firmware or a combination of these implementation methods. The embodiments of the present application can be implemented as a computer program or program code executed on a programmable system, which includes at least one processor, a storage system (including volatile and non-volatile memory and / or storage elements), at least one input device and at least one output device.

[0121] Program code can be applied to input instructions to perform the functions described in this application and generate output information. The output information can be applied to one or more output devices in a known manner. For the purposes of this application, a processing system includes any system having a processor such as, for example, a digital signal processor (DSP), a microcontroller, an application specific integrated circuit (ASIC), or a microprocessor.

[0122] Program code can be implemented with high-level programming language or object-oriented programming language to communicate with the processing system. When necessary, program code can also be implemented with assembly language or machine language. In fact, the mechanism described in this application is not limited to the scope of any specific programming language. In either case, the language can be a compiled language or an interpreted language.

[0123] In some cases, the disclosed embodiments may be implemented in hardware, firmware, software, or any combination thereof. The disclosed embodiments may also be implemented as instructions carried or stored on one or more temporary or non-temporary machine-readable (e.g., computer-readable) storage media, which may be read and executed by one or more processors. For example, instructions may be distributed over a network or through other computer-readable media. Therefore, machine-readable media may include any mechanism for storing or transmitting information in a machine (e.g., computer) readable form, including, but not limited to, floppy disks, optical disks, optical disks, read-only memories (CD-ROMs), magneto-optical disks, read-only memories (ROMs), random access memories (RAMs), erasable programmable read-only memories (EPROMs), electrically erasable programmable read-only memories (EEPROMs), magnetic or optical cards, flash memory, or a tangible machine-readable memory for transmitting information (e.g., carrier waves, infrared signals, digital signals, etc.) using the Internet in electrical, optical, acoustic, or other forms of propagation signals. Therefore, machine-readable media include any type of machine-readable media suitable for storing or transmitting electronic instructions or information in a machine (e.g., computer) readable form.

[0124] In the accompanying drawings, some structural or method features may be shown in a specific arrangement and / or order. However, it should be understood that such a specific arrangement and / or order may not be required. Instead, in some embodiments, these features may be arranged in a manner and / or order different from that shown in the illustrative drawings. In addition, the inclusion of structural or method features in a particular figure does not mean that such features are required in all embodiments, and in some embodiments, these features may not be included or may be combined with other features.

[0125] It should be noted that the units / modules mentioned in the various device embodiments of the present application are all logical units / modules. Physically, a logical unit / module can be a physical unit / module, or a part of a physical unit / module, or can be implemented as a combination of multiple physical units / modules. The physical implementation method of these logical units / modules themselves is not the most important. The combination of functions implemented by these logical units / modules is the key to solving the technical problems proposed by the present application. In addition, in order to highlight the innovative part of the present application, the above-mentioned device embodiments of the present application do not introduce units / modules that are not closely related to solving the technical problems proposed by the present application, which does not mean that there are no other units / modules in the above-mentioned device embodiments.

[0126] It should be noted that in the examples and description of this patent, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "including one" do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0127] Although the present application has been illustrated and described with reference to certain preferred embodiments thereof, it will be apparent to those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present application.

Claims

1. An interference elimination method, applied to an electronic device including a first channel and a second channel with a signal receiving function, characterized in that: include: Collecting a measurement signal mixed with a valid signal and a first interference signal from the first-type channel, and collecting a second interference signal from the second-type channel; According to the formula The coefficient c is obtained by the first calibration data and the second calibration data i,j , the coefficient c i,j is used to represent the coupling relationship between the first calibration data and the second calibration data, and the coefficient c i,j is a time-invariant convolution kernel coefficient; wherein the size of the convolution kernel is 2K+1, K is a natural number, s r,t is the tth sampling data from the rth first-category channel in the first calibration data, s i,j is the j-th sampling data from the i-th second-category channel in the second calibration data, the electronic device includes M second-category channels and N first-category channels, i is a positive integer from 1 to M, and r is a positive integer from 1 to N; According to the formula and the coefficient c i,j and the second interference signal, to estimate the first interference signal; wherein, s ′ t,t is the tth sampled data from the rth first-category channel in the first interference signal, s ′ i,j is the j-th sampled data from the i-th second-category channel in the second interference signal; Removing the first interference signal from the measurement signal to obtain a target effective signal; The first calibration data and the second calibration data are interference signals respectively collected from the first channel and the second channel when the electronic device is in a preset state.

2. The method according to claim 1, characterized in that The coupling relationship is used to represent the frequency domain correlation between the interference signal in the first type of channel and the second type of channel, and the coupling relationship is continuous and smooth in the frequency domain.

3. The method according to claim 1, characterized in that According to the formula The first calibration data and the second calibration data obtain coefficient c i,j ,include: According to the formula For each sampled data from the r first-category channels in the first calibration data, an equation with a convolution kernel coefficient as an unknown is obtained respectively, and the equations corresponding to all the sampled data of the r first-category channels are combined to obtain a linear equation group, and the coefficient c is obtained by solving the linear equation group. i,j .

4. The method according to any one of claims 1 to 3, characterized in that The electronic device is a magnetic resonance imaging device, the effective signal is a magnetic resonance imaging signal, and the interference signal includes at least one of an electromagnetic interference signal and thermal noise; The first type of channel is realized by one or more phased array coils; the second type of channel is realized by one or more phased array coils, or one or more electrodes attached to the surface of the detection object.

5. The method according to any one of claims 1 to 3, characterized in that The electronic device is a synchronous EEG-FMRI device, the effective signal is an EEG signal, and the interference signal includes at least one of a radio frequency signal and a gradient signal generated by the MRI device; The first type of channel is realized by one or more electrodes attached to the surface of the detection object; the second type of channel is realized by one or more electrodes attached to the surface of the detection object, or one or more phased array coils.

6. The method according to any one of claims 1 to 3, characterized in that The electronic device is a magnetic resonance imaging device including a transmitting coil, and the preset state is turning off the transmitting coil; The method further comprises: In the case of being in the preset state, the signal collected from the first type of channel is used as the first calibration data, and the signal collected from the second type of channel is used as the second calibration data; The radio frequency signal transmitted by the transmitting coil is used to stimulate the first type of channel to receive a valid signal.

7. The method according to any one of claims 1 to 3, characterized in that The preset state is that the signals in the first-category channel and the second-category channel are collected multiple times; The method further comprises: In the case of being in the preset state, taking the first signal as the first calibration data and the second signal as the second calibration data; The first signal is the difference between two consecutive signals collected from the first type of channel, and the second signal is the difference between two consecutive signals collected from the second type of channel in the first interference signal.

8. The method according to any one of claims 1 to 3, characterized in that The electronic device is a magnetic resonance imaging device including a gradient coil, and the preset state is within a dead time during which the measurement signal and the second interference signal are acquired; In the case of being in the preset state, using the damaged gradient damaged effective signal from the gradient coil, taking the signal collected from the first type of channel as the first calibration data, and taking the signal collected from the second type of channel as the second calibration data; The dead time is the time used to wait for the transverse or longitudinal magnetization vector to recover to its original state when the magnetic resonance imaging device performs magnetic resonance imaging.

9. The method according to any one of claims 1 to 3, characterized in that The electronic device is a magnetic resonance imaging device including a transmitting coil, and the preset state is that the high-frequency signal in the frequency domain space of the signals collected from the first channel and the second channel is dominated by electromagnetic interference; The method further comprises: The high-frequency signal of the measurement signal in the frequency domain space is used as the first calibration data, and the high-frequency signal of the second interference signal in the frequency domain space is used as the second calibration data.

10. The method according to claim 1, characterized in that The measurement signal is one-dimensional or multi-dimensional data, and the convolution kernel is a one-dimensional or multi-dimensional convolution kernel.

11. A computer-readable storage medium, characterized in that: The storage medium stores instructions, and when the instructions are executed on a computer, the computer is caused to execute the interference elimination method according to any one of claims 1 to 10.

12. An electronic device, characterized in that: include: one or more processors; One or more memories; the one or more memories store one or more programs, and when the one or more programs are executed by the one or more processors, the electronic device executes the interference elimination method described in any one of claims 1 to 10.

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