CN110811610A - Multichannel bioelectric signal acquisition system and control method thereof - Google Patents

Abstract

The embodiment of the invention provides a multichannel bioelectricity signal acquisition system and a control method thereof, wherein the system comprises: the system comprises N electrode leads, M reference leads, a driving lead, a preprocessing channel, a synchronous analog-digital conversion module, a controller, a communication module and a power supply; the signal acquisition system is used for synchronously acquiring signals of electroencephalogram, electrocardio, myoelectricity, electrooculogram and the like of a living body in a multi-channel manner. The multichannel analog-to-digital conversion modules share a clock signal and an initial signal, multichannel synchronous acquisition is guaranteed, common mode rejection ratio and measurement reliability are improved by means of offset driving, broken line detection and the like, high-frequency and power-frequency noise interference is suppressed through a low-pass filter, a power-frequency wave trap and the like, high quality of bioelectricity signal acquisition of more channels is guaranteed, and accuracy is improved. In addition, in order to improve portability, a 5G communication module is preferably adopted to perform data interaction with a cloud device or a computer.

Description

Multichannel bioelectric signal acquisition system and control method thereof

Technical Field

The embodiment of the invention relates to the technical field of bioelectricity detection, in particular to a multichannel bioelectricity signal acquisition system and a control method thereof.

Background

Some parts of the human body can spontaneously generate weak bioelectric signals, most typically electroencephalogram signals, electrocardio signals, myoelectricity signals and electro-oculogram signals. These signals may reflect diseases, movements, mental states and even thoughts of the human body. The signals are accurately collected, so that various diseases of the human body can be researched and predicted on one hand. On the other hand, the idea of the person can be analyzed, so that the external equipment can be controlled. Therefore, the bioelectricity collection system is widely applied to scientific research, military, medical treatment, life assistance and other aspects, and has important practical significance.

Among the above signals, the brain electrical signal is the most complex and the weakest signal. Electroencephalogram acquisition provides raw data for brain science research. In many related technologies of brain science research, electroencephalogram signal acquisition is a key and fundamental item. The multi-channel synchronous acquisition is required, external factors are easily caused, the multi-channel synchronous acquisition is particularly easily influenced by electrooculogram, myoelectricity and electrocardio, and the acquisition difficulty is high.

Therefore, how to provide a bioelectric signal acquisition scheme, which can acquire more bioelectric signals, reduce mutual interference of various electric signals, improve accuracy of electroencephalogram signals, and facilitate research is a technical problem to be solved by those skilled in the art.

Disclosure of Invention

In order to solve all or part of the technical problems, the invention provides a multi-channel bioelectric signal acquisition system and a control method thereof, which can synchronously acquire one or more bioelectric signals and can adapt to more bioelectric measurement application occasions.

In order to achieve the above purpose, the invention provides the following technical scheme:

in a first aspect, an embodiment of the present invention provides a multichannel bioelectrical signal acquisition system, including: the system comprises N electrode leads, M reference leads, a driving lead, a preprocessing channel, a synchronous analog-digital conversion module, a controller, a communication module and a power supply; wherein N is an integer greater than 1, and M is a positive integer;

the N electrode leads are used for being connected with a measuring electrode connected to a living body and receiving a bioelectrical signal acquired by the measuring electrode;

m of said reference leads for connection to reference electrodes connected to the biological body for use as reference potentials for N of said electrode leads;

the drive lead is connected with the offset drive output of the analog-to-digital conversion module through a protection circuit and is used for outputting an offset drive signal so as to improve the common mode rejection capability; the protection circuit is used for limiting the current output by the offset drive so as to avoid damage to organisms;

the receiving end of the preprocessing channel is connected with the N electrode leads or the M reference leads and is used for preprocessing bioelectrical signals acquired by the N electrode leads or the M reference leads to acquire bioelectrical output signals;

the synchronous analog-to-digital conversion module is used for carrying out parallel synchronous acquisition on the bioelectricity output signals; the controller is connected with the digital interface of the analog-to-digital conversion module, connected with the control end of the preprocessing circuit and used for setting parameters of the preprocessing circuit and the analog-to-digital conversion module; controlling the preprocessing channel to preprocess the bioelectrical signals acquired by the N electrode leads or the M reference leads to acquire bioelectrical output signals; controlling the analog-to-digital conversion module to perform parallel synchronous acquisition and analog-to-digital conversion on the bioelectricity output signals; receiving the bioelectric signal output by the analog-to-digital conversion module;

the communication module is connected with the controller and is used for being in communication connection with external equipment; the controller rapidly transmits the bioelectricity signal output by the analog-to-digital conversion module to external equipment through the communication module;

the power module is the preprocessing channel, the synchronous analog-to-digital conversion module, the controller and the communication module provide power support.

Preferably, the bioelectric signal comprises: electroencephalogram signals, electrocardiosignals, myoelectricity signals and eye electric signals.

Preferably, the analog-to-digital conversion module includes:

an offset signal unit for generating an offset driving signal;

the broken line detection unit is used for realizing a broken line detection function;

and the analog-to-digital conversion unit is used for converting the analog signal into a digital signal.

Preferably, the preprocessing circuit comprises: the protection device comprises a blocking capacitor, a low-pass filter, a power frequency wave trap and a controllable amplifier;

the protection device is connected with the electrode lead or the reference lead and is used for protecting a rear-stage circuit;

the front stage of the blocking capacitor is connected with the lead protection device, and the rear stage of the blocking capacitor is connected with the low-pass filter; the device is used for filtering out a direct current component in an original bioelectricity signal; when the direct current component does not need to be filtered, the direct current component is short-circuited through the controllable switch 1; when an offset driving circuit or an electrode disconnection detection circuit is adopted, the controllable switch 1 is closed, and the blocking capacitor is short-circuited;

the front stage of the low-pass filter is connected with the blocking capacitor module, and the rear stage of the low-pass filter is connected with the power frequency wave trap; the device is used for filtering out unwanted external high-frequency interference signals;

the power frequency wave trap is connected with the low-pass filter and the controllable amplifier; the device is used for filtering out coupled power frequency interference signals in the original bioelectricity signals;

the controllable amplifier is connected with the power frequency wave trap and the analog-to-digital conversion module, and the control end of the controllable amplifier is connected with the controller; the device is used for controllably amplifying the original bioelectric signal, and a control signal of the device is sent by the controller; when the original bioelectric signal does not need to be amplified, the bioelectric signal can be short-circuited through the controllable switch 2; the gain of the controllable switch 2 and the controllable amplifier is controlled by the controller.

Preferably, the synchronous analog-to-digital conversion module and the preprocessing channel are respectively connected with the controller, so that the synchronous acquisition of signals of a plurality of analog-to-digital conversion devices can be realized, and unified initial signals and clock signals are provided;

when any ADC can realize synchronous acquisition of multiple paths of bioelectricity output signals; the device is provided with a reference signal input port; outputting a path of offset driving signal; the function of detecting broken wires is realized;

each analog-to-digital conversion module is provided with an on-chip or external accurate clock source and a reference source;

when the configuration of a plurality of analog-to-digital conversion modules is the same, more than one ADC is connected in a daisy chain mode so as to save the digital interface of the controller; when different configuration possibilities exist in a plurality of analog-to-digital conversion modules, the analog-to-digital conversion modules are respectively connected with the digital interface of the controller according to a standard mode.

Preferably, the controller is connected with each channel of preprocessing module, each channel analog-to-digital conversion module, the memory and the communication interface; the system is used for realizing the overall control of the bioelectricity signal acquisition system, the parameter configuration of each module, the receiving of ADC output signals and the sending of data to an upper computer;

the controller is realized by programming of a DSP, an ARM or an FPGA device.

Preferably, the communication module is a 5G wireless communication module; the system is used for sending all data acquired by the bioelectricity signal acquisition system to cloud equipment or an upper computer.

Preferably, the 5G wireless communication module is in communication connection with an external device with a 5G transceiver module;

the outside plant includes: the system comprises network cloud equipment connected to a 5G network and/or a bioelectricity signal processing computer connected to the 5G network;

the network cloud equipment is used for carrying out instant storage or instant action response on the bioelectricity output signal;

and the bioelectrical signal processing computer is used for carrying out instant processing on the bioelectrical output signal.

Preferably, the analog-to-digital conversion module adopts a unipolar lead mode or a bipolar lead mode; when a unipolar lead is adopted, the P end fed-in signals of each electrode lead connected with the analog-to-digital conversion module use the reference lead fed-in signals as reference potential; when bipolar leads are used, the P end of each electrode lead takes the N end of the corresponding electrode lead as a reference potential.

In a second aspect, an embodiment of the present invention provides a method for controlling a multichannel bioelectrical signal acquisition system, which is applied to the multichannel bioelectrical signal acquisition system according to any one of the above first aspects, and includes:

setting parameters of a preprocessing circuit and an analog-to-digital conversion module;

controlling the preprocessing channel to preprocess the bioelectrical signals acquired by the N electrode leads or the M reference leads to acquire bioelectrical output signals;

controlling the analog-to-digital conversion module to perform parallel synchronous acquisition and analog-to-digital conversion on the bioelectricity output signals;

and receiving the bioelectrical signal output by the analog-to-digital conversion module.

The embodiment of the invention provides a multichannel bioelectricity signal acquisition system, which comprises: the system comprises N electrode leads, M reference leads, a driving lead, a preprocessing channel, a synchronous analog-digital conversion module, a controller, a communication module and a power supply; wherein N is an integer greater than 1, and M is a positive integer; the N electrode leads are used for being connected with a measuring electrode connected to a living body and receiving a bioelectrical signal acquired by the measuring electrode; m of said reference leads for connection to reference electrodes connected to the biological body for use as reference potentials for N of said electrode leads; the drive lead is connected with the offset drive output of the analog-to-digital conversion module through a protection circuit and is used for outputting an offset drive signal so as to improve the common mode rejection capability; the protection circuit is used for limiting the current output by the offset drive so as to avoid damage to organisms; the receiving end of the preprocessing channel is connected with the N electrode leads or the M reference leads and is used for preprocessing bioelectrical signals acquired by the N electrode leads or the M reference leads to acquire bioelectrical output signals; the synchronous analog-to-digital conversion module is used for carrying out parallel synchronous acquisition on the bioelectricity output signals; the controller is connected with the digital interface of the analog-to-digital conversion module, connected with the control end of the preprocessing circuit and used for setting parameters of the preprocessing circuit and the analog-to-digital conversion module; controlling the preprocessing channel to preprocess the bioelectrical signals acquired by the N electrode leads or the M reference leads to acquire bioelectrical output signals; controlling the analog-to-digital conversion module to perform parallel synchronous acquisition and analog-to-digital conversion on the bioelectricity output signals; receiving the bioelectric signal output by the analog-to-digital conversion module; the communication module is connected with the controller and is used for being in communication connection with external equipment; the controller rapidly transmits the bioelectricity signal output by the analog-to-digital conversion module to external equipment through the communication module; the power module is the preprocessing channel, the synchronous analog-to-digital conversion module, the controller and the communication module provide power support. The invention can collect more bioelectric signals, inhibit common-mode interference, detect the electrode connection state, reduce the mutual interference of various electric signals, improve the accuracy of electroencephalogram signals and facilitate research.

The multi-channel bioelectric signal acquisition system and the control method thereof provided by the embodiment of the invention have the same beneficial effects, and are not repeated herein.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It should be apparent that the drawings in the following description are merely exemplary, and that other embodiments can be derived from the drawings provided by those of ordinary skill in the art without inventive effort.

The structures, ratios, sizes, and the like shown in the present specification are only used for matching with the contents disclosed in the specification, so as to be understood and read by those skilled in the art, and are not used to limit the conditions that the present invention can be implemented, so that the present invention has no technical significance, and any structural modifications, changes in the ratio relationship, or adjustments of the sizes, without affecting the effects and the achievable by the present invention, should still fall within the range that the technical contents disclosed in the present invention can cover.

FIG. 1 is a schematic diagram of a multi-channel bioelectrical signal acquisition system according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a pre-processing circuit according to an embodiment of the present invention;

fig. 3 is a schematic diagram of a circuit structure of a dual T-type wave trap according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of a unipolar lead implementation of a multichannel bioelectrical signal acquisition system according to an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of a bipolar lead implementation of a multi-channel bioelectrical signal acquisition system according to an embodiment of the present invention;

FIG. 6 is a schematic diagram illustrating a daisy chain connection among a plurality of ADCs according to an embodiment of the present invention;

FIG. 7 is a diagram illustrating a standard connection between multiple ADCs according to an embodiment of the present invention;

FIG. 8 is a schematic diagram of the interaction between a multi-channel bioelectrical signal acquisition system and an external device using a 5G module according to an embodiment of the present invention;

fig. 9 is a flowchart of a control method of a bioelectrical signal acquisition system according to an embodiment of the present invention.

Detailed Description

The present invention is described in terms of particular embodiments, other advantages and features of the invention will become apparent to those skilled in the art from the following disclosure, and it is to be understood that the described embodiments are merely exemplary of the invention and that it is not intended to limit the invention to the particular embodiments disclosed. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1, fig. 2, fig. 3, fig. 4, fig. 5, fig. 6, fig. 7 and fig. 8, fig. 1 is a schematic structural diagram of a multi-channel bioelectrical signal acquisition system according to an embodiment of the present invention; FIG. 2 is a schematic diagram of a pre-processing circuit according to an embodiment of the present invention; fig. 3 is a schematic diagram of a circuit structure of a dual T-type wave trap according to an embodiment of the present invention; FIG. 4 is a schematic diagram of a unipolar lead implementation of a multichannel bioelectrical signal acquisition system according to an embodiment of the present invention; FIG. 5 is a schematic structural diagram of a bipolar lead implementation of a multi-channel bioelectrical signal acquisition system according to an embodiment of the present invention; FIG. 6 is a schematic diagram illustrating a daisy chain connection among a plurality of ADCs according to an embodiment of the present invention; FIG. 7 is a diagram illustrating a standard connection between multiple ADCs according to an embodiment of the present invention; fig. 8 is a schematic diagram of interaction between a multichannel bioelectrical signal acquisition system and an external device by using a 5G module according to an embodiment of the present invention.

The embodiment of the invention provides a multichannel bioelectricity signal acquisition system, which comprises: the system comprises N electrode leads, M reference leads, a driving lead, a preprocessing channel, a synchronous analog-digital conversion module, a controller, a communication module and a power supply; wherein N is an integer greater than 1, and M is a positive integer; the N electrode leads are used for being connected with a measuring electrode connected to a living body and receiving a bioelectrical signal acquired by the measuring electrode; m of said reference leads for connection to reference electrodes connected to the biological body for use as reference potentials for N of said electrode leads; the drive lead is connected with the offset drive output of the analog-to-digital conversion module through a protection circuit and is used for outputting an offset drive signal so as to improve the common mode rejection capability; the protection circuit is used for limiting the current output by the offset drive so as to avoid damage to organisms; the receiving end of the preprocessing channel is connected with the N electrode leads or the M reference leads and is used for preprocessing bioelectrical signals acquired by the N electrode leads or the M reference leads to acquire bioelectrical output signals; the synchronous analog-to-digital conversion module is used for carrying out parallel synchronous acquisition on the bioelectricity output signals; the controller is connected with the digital interface of the analog-to-digital conversion module, connected with the control end of the preprocessing circuit and used for setting parameters of the preprocessing circuit and the analog-to-digital conversion module; controlling the preprocessing channel to preprocess the bioelectrical signals acquired by the N electrode leads or the M reference leads to acquire bioelectrical output signals; controlling the analog-to-digital conversion module to perform parallel synchronous acquisition and analog-to-digital conversion on the bioelectricity output signals; receiving the bioelectric signal output by the analog-to-digital conversion module; the communication module is connected with the controller and is used for being in communication connection with external equipment; the controller rapidly transmits the bioelectricity signal output by the analog-to-digital conversion module to external equipment through the communication module; the power module is the preprocessing channel, the synchronous analog-to-digital conversion module, the controller and the communication module provide power support.

In particular, the communication module is preferably a 5G communication module and/or a USB communication module. Optionally, the system further comprises a memory connected to the controller for storing the collected bioelectrical signal data. The electrode leads are responsible for feeding the measuring electrodes arranged on various parts of the body of the user into a preprocessing channel of the bioelectrical signal acquisition system. The reference leads are responsible for feeding the reference electrodes corresponding to the measurement electrodes into the preprocessing channel of the bioelectrical signal acquisition system. One reference lead may correspond to a plurality of electrode leads. And driving the lead, and feeding the offset driving signal output by the analog-to-digital conversion module into a certain part of a human body. When the electroencephalogram or the electrooculogram is measured, the driving lead is usually connected to the earlobe or the mastoid of a person, and when the electrocardio or the myoelectricity is measured, the driving lead is usually connected to the right leg of the person. Alternatively, the electrode leads, reference leads, and drive leads may specifically include dry and/or wet electrodes, electrode feed lines, and electrical interfaces (e.g., BNC interfaces).

The electro-oculogram, myoelectricity and electrocardio signals are synchronously collected with the electroencephalogram signals, so that interference signals in the electroencephalogram signals can be offset to a certain extent, and the accuracy of electroencephalogram collection is improved. The electrocardiosignals can be helpful for judging cardiovascular related diseases of patients and mood fluctuation of the patients; for electroencephalogram application by utilizing motor imagery, more accurate and rapid judgment can be obtained by combining myoelectric signals; the electric eye signals and the brain electrical signals have close relation, and particularly in sleep quality evaluation and imagination-related research, the electric eye signals need to be combined for analysis.

In order to accurately acquire the bioelectrical signals, on one hand, the electrodes need to be ensured to be connected perfectly, and external interference is eliminated as much as possible. In a typical environment, the main sources of interference are power frequency (50Hz) signals, and high frequency radio waves in the environment. In addition, interference is often superimposed on each signal in a common mode, so that the common mode rejection ratio of the signals needs to be improved. On the other hand, the bioelectricity signals of microvolt level can be accurately acquired by adopting proper amplification factor and ADC digit.

Most of the existing bioelectric signal acquisition systems adopt wired signal transmission and can only be applied to certain medical and experimental places. For the convenience of application in life, the bioelectrical signal acquisition system should have wireless data communication capability. And because the data volume that the bioelectricity collection system needs to transmit in real time is great, therefore need to adopt the extremely fast wireless transmission mode of data transmission speed.

The electrode lead and the reference lead are respectively connected with respective preprocessing channels. The pretreatment channel configuration is shown in FIG. 2. The protection circuit is used for preventing human body electrostatic breakdown or interference on normal work of the multi-channel bioelectricity acquisition system and preventing the bioelectricity acquisition system from electric leakage to hurt the human body. The protection circuit can be realized by TVS tube, Zener diode, gas discharge tube and other devices.

Generally, due to environmental influence, the bioelectricity signals are superposed with direct current drift irrelevant to the signals, and because the bioelectricity signals are often very weak, especially the electroencephalogram signals are lower than the direct current drift signals by 2-3 orders of magnitude sometimes. In order to prevent the signal from being submerged by the DC drift signal, the bioelectric signal is filtered by a DC blocking capacitor in the preprocessing channel. When the direct current nearby bioelectric signals need to be researched, the direct current blocking capacitor can be short-circuited through the controllable switch 1 connected with the direct current blocking capacitor in parallel. The controllable switch 1 is controlled by a controller.

Generally, the frequency of the bioelectrical signal is concentrated in the frequency range of 0.5-100 Hz, and in order to prevent the radio high-frequency signal widely existing in the environment from interfering with the weak electroencephalogram signal, a low-pass filter is adopted in a preprocessing channel to filter out the unnecessary high-frequency signal component.

An industrial frequency alternating current signal of 50Hz is commonly existed in the environment, and the frequency is in the frequency range of the bioelectricity signal. In order to accurately collect the bioelectric signals, the preprocessing channel utilizes a power frequency wave trap to filter 50Hz power frequency signals in the environment from the bioelectric signals. In order to not influence the bioelectric signals beyond the power frequency as much as possible, the wave trap should have the characteristics of narrow bandwidth, high Q value and consistent center frequency with the power frequency. Preferably, a double T trap structure as shown in figure 3 is used.

Optionally, the preprocessing circuit further comprises a controllable amplifier for amplifying the weak raw bioelectric signal to an amplitude range convenient for acquisition, so as to distinguish more details of the bioelectric signal. When amplification of the raw bioelectric signal is not required, it can be short-circuited by means of the controllable switch 2. The gain of the controllable switch 2 and the controllable amplifier is controlled by the controller. Preferably, the controllable amplifier is realized by an instrumentation amplifier with a three-operational amplifier structure, wherein the common-mode rejection ratio of the controllable amplifier is high, the input impedance is high, and the input noise is low.

And the synchronous analog-to-digital conversion module is used for carrying out parallel synchronous acquisition on the multi-path bioelectricity output signals. Synchronous acquisition of a plurality of analog-to-digital conversion devices (ADC) can be realized, and a unified START Signal (START) and a clock signal (CLK) are provided. Any ADC can realize synchronous acquisition of multi-path bioelectricity output signals; the device is provided with a reference signal input port; the offset driving signal generation and the disconnection detection function can be realized. Each analog-to-digital conversion module is provided with an on-chip or external precise clock source and a reference source. Any analog-to-digital conversion module can select a unipolar lead mode or a bipolar lead mode for acquisition. When a unipolar lead is used, the signals fed into the P terminal of each electrode lead connected to the analog-to-digital conversion module use the reference lead feed signal as a reference potential. When bipolar leads are adopted, the P end of each electrode lead takes the corresponding N end of the lead as a reference potential. A schematic diagram of the structure of the unipolar and bipolar leads is shown in fig. 4. When the configuration of the plurality of analog-to-digital conversion modules is the same, optionally, the plurality of ADCs are connected in a daisy chain manner, so as to save a digital interface of the controller. When different configuration possibilities exist in a plurality of analog-to-digital conversion modules, the analog-to-digital conversion modules are respectively connected with the digital interface of the controller according to a standard mode. The daisy chain connection and the standard connection are shown in fig. 5.

The analog-to-digital conversion module of the system is preferably a bioelectricity collection analog-to-digital converter represented by ADS1299-x series.

And the controller is responsible for realizing the functions of overall control of the system, parameter configuration of each module, receiving of ADC output signals, sending of bioelectricity signals to the upper computer through the communication module and the like. The signal after analog-to-digital conversion is output to a controller. And then the signals are transmitted to a computer or cloud equipment which is also connected with the 5G wireless transceiver module at a high speed through the 5G wireless transceiver module according to a certain queue sequence, the computer or the cloud equipment runs upper computer software and a corresponding algorithm, the bioelectric signals are analyzed, and a bioelectric diagram is drawn or corresponding control operation is executed. In one embodiment, the controller may be implemented by an ARM chip, or an FPGA chip, or a DSP chip, etc.

In fact, after the system is started, the upper computer can write default parameters into corresponding register positions in the controller to initialize the bioelectricity collection system. And then parameters of the preprocessing module and the analog-to-digital conversion module can be automatically or manually adjusted by a user according to the application requirements, and the acquired data is transmitted back to the upper computer.

And the communication module is responsible for sending all data acquired by the bioelectricity signal acquisition system to the cloud equipment or the upper computer. Because the data volume that needs to transmit is huge, in order to guarantee the real-time nature of signal transmission, the 5G wireless communication module realization of preferred.

On the basis of the specific embodiment, in order to prevent the controller or the external equipment from processing the bioelectric signal data in time, and causing data loss, the controller can be connected with a memory, and can temporarily store and permanently store the bioelectric signal data, so that when the bioelectric signal acquisition system is not networked, the bioelectric signal data can be acquired and stored, and later-stage utilization is facilitated.

The 5G communication module is in communication connection with external equipment with a 5G transceiver module; the outside plant includes: the system comprises network cloud equipment connected to a 5G network and/or a bioelectricity signal processing computer connected to the 5G network; the network cloud equipment is used for carrying out instant storage or response action on the bioelectricity signal; and the bioelectrical signal processing computer is used for carrying out instant processing on the bioelectrical signal. Certainly, after the external device is in communication connection with the bioelectrical signal acquisition system, the authority of the external device may also be identified, and the external device may adjust the control parameter of the controller, for example, the gain of a controllable amplifier of the controller-controlled preprocessing module may be adjusted, the sampling rate of the analog signal in the analog-to-digital conversion module may also be adjusted, and of course, the parameter that may be controlled by another controller may also be adjusted.

In one embodiment, the analog-to-digital conversion module is implemented by a plurality of ADS1299-8 chips. The ADS1299-8 chip has an 8-way programmable amplifier (PGA) integrated therein, with a built-in oscillator and reference voltage source. An ADS1299-8 corresponds to up to 8 sets of measurement electrodes, one reference electrode and one drive electrode. When a single-pole lead mode is adopted, 8 measurement electrode signals are fed into the P end of each group of channels, namely the positive end of each PGA, after passing through the preprocessing circuit respectively, and the reference electrode signal is fed into the N end of each group of channels, namely the negative end of each PGA, after passing through the preprocessing circuit simultaneously. The difference between the P-N signals is amplified by PGA and then is subjected to synchronous analog-to-digital conversion. When bipolar leads are used, each group of electrode leads contains signals of two electrodes, which are fed into the P end and the N end of each group of channels after passing through the preprocessing circuit respectively. Namely, when bipolar leads are used, the AD1299-8 is simultaneously connected with 16 input electrodes, wherein every two input electrodes are used as a group of input signals, and the difference between signals at the P-N ends is amplified by the PGA and then is subjected to synchronous analog-to-digital conversion. The multiple ADS1299-8 share the same clock signal CLK and the same START signal START to ensure the synchronization of sampling. The clock signal may be generated by an external clock source and the acquisition start signal generated by the controller. ADS1299-8 integrates an offset driving circuit, can take an offset driving signal thereof as a right leg driving signal, directly connects the right leg driving signal to each corresponding part of a human body, and realizes negative feedback regulation on each measuring electrode, thereby achieving the purposes of inhibiting common mode interference and offsetting the bioelectricity signal to a proper voltage range. For different kinds of bioelectrical signals, the signal amplitude difference is large, or the physiological positions are far apart. The different way ADS1299-8 is preferably used for the acquisition. ADS1299-8 also integrates an electrode disconnection detection circuit, and can detect whether each measuring electrode is firmly contacted with the corresponding position of the human body in real time. When an offset driving circuit and an electrode disconnection detection circuit are adopted, the controllable switch 1 is closed to short circuit the blocking capacitor. The communication interface between ADS1299-8 and the controller is SPI interface. The ADSs 1299-8 may be daisy-chained to the controller so that only 1 SPI interface of the controller is occupied and data from the ADSs 1299-8 is output sequentially. However, when the configurations of the ADSs 1299-8 are different, for example, when different ADSs 1299-8 are respectively connected with electroencephalogram, electrocardio, myoelectricity and electrooculogram, the PGA amplification factors inside the ADSs 1299-8 should be set differently, so that the ADSs 1299-8 cannot adopt a daisy chain connection mode, but should adopt a standard connection mode, that is, each of the ADSs 1299-8 respectively occupies 1 SPI interface of the controller for data communication.

The inventor of the application finds that some bioelectricity signals can be accurately measured only by measuring in actual life, and the conventional bioelectricity signal acquisition equipment restricts the acquisition accuracy of the bioelectricity signals. The inventor of the application can carry out the acquisition of bioelectricity signal in people's actual life in order to make the measurement of bioelectricity signal more accurate, therefore utilize 5G communication module, make the bioelectricity signal acquisition system that can carry out the application in actual life, and convenient to use person carries, can adapt to more application occasions.

The embodiment of the invention increases the portability of the bioelectricity collection system. The bioelectricity acquisition system adopting wireless signal transmission has the defect of slow communication speed. Therefore, the embodiment of the invention provides a bioelectricity signal acquisition system based on 5G wireless communication, and China officially issues a 5G operation license plate, which means that China officially enters the 5G era. In the future, 5G communication can be widely applied in China, and corresponding supporting software and hardware supporting facilities can be rapidly completed. The 5G communication has the characteristics of ultra-reliability, low time delay, wide bandwidth and high speed, and by means of the strong performance of the 5G communication, the bioelectric signal quick communication can be realized, and more bioelectric data can be transmitted in the same time without data simplification as before. Therefore, the embodiment of the invention can comprehensively improve the real-time performance, accuracy and portability of bioelectricity signal acquisition.

Referring to fig. 9, fig. 9 is a flowchart illustrating a control method of a bioelectrical signal acquisition system according to an embodiment of the present invention.

The embodiment of the invention provides a control method of a bioelectrical signal acquisition system, which is applied to the bioelectrical signal acquisition system in any one of the above embodiments, and comprises the following steps:

step S11: setting parameters of a preprocessing circuit and an analog-to-digital conversion module;

step S12: controlling the preprocessing channel to preprocess the bioelectrical signals acquired by the N electrode leads or the M reference leads to acquire bioelectrical output signals;

step S13: controlling the analog-to-digital conversion module to perform parallel synchronous acquisition and analog-to-digital conversion on the bioelectricity output signals;

step S14: and receiving the bioelectrical signal output by the analog-to-digital conversion module.

Although the invention has been described in detail above with reference to a general description and specific examples, it will be apparent to one skilled in the art that modifications or improvements may be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.

Claims (10)

1. A multi-channel bioelectrical signal acquisition system, comprising: the system comprises N electrode leads, M reference leads, a driving lead, a preprocessing channel, a synchronous analog-digital conversion module, a controller, a communication module and a power supply; wherein N is an integer greater than 1, and M is a positive integer;

the N electrode leads are used for being connected with a measuring electrode connected to a living body and receiving a bioelectrical signal acquired by the measuring electrode;

m of said reference leads for connection to reference electrodes connected to the biological body for use as reference potentials for N of said electrode leads;

the drive lead is connected with the offset drive output of the analog-to-digital conversion module through a protection circuit and is used for outputting an offset drive signal so as to improve the common mode rejection capability; the protection circuit is used for limiting the current output by the offset drive so as to avoid damage to organisms;

the receiving end of the preprocessing channel is connected with the N electrode leads or the M reference leads and is used for preprocessing bioelectrical signals acquired by the N electrode leads or the M reference leads to acquire bioelectrical output signals;

the synchronous analog-to-digital conversion module is used for carrying out parallel synchronous acquisition on the bioelectricity output signals; the controller is connected with the digital interface of the analog-to-digital conversion module, connected with the control end of the preprocessing circuit and used for setting parameters of the preprocessing circuit and the analog-to-digital conversion module; controlling the preprocessing channel to preprocess the bioelectrical signals acquired by the N electrode leads or the M reference leads to acquire bioelectrical output signals; controlling the analog-to-digital conversion module to perform parallel synchronous acquisition and analog-to-digital conversion on the bioelectricity output signals; receiving the bioelectric signal output by the analog-to-digital conversion module;

the communication module is connected with the controller and is used for being in communication connection with external equipment; the controller rapidly transmits the bioelectricity signal output by the analog-to-digital conversion module to external equipment through the communication module;

the power module is the preprocessing channel, the synchronous analog-to-digital conversion module, the controller and the communication module provide power support.

2. The bioelectrical signal acquisition system according to claim 1,

the bioelectric signal includes: electroencephalogram signals, electrocardiosignals, myoelectricity signals and eye electric signals.

3. The bioelectrical signal acquisition system according to claim 1,

the analog-to-digital conversion module comprises:

an offset signal unit for generating an offset driving signal;

the broken line detection unit is used for realizing a broken line detection function;

and the analog-to-digital conversion unit is used for converting the analog signal into a digital signal.

4. The bioelectrical signal acquisition system according to claim 1, wherein the preprocessing circuit comprises: the protection device comprises a blocking capacitor, a low-pass filter, a power frequency wave trap and a controllable amplifier;

the protection device is connected with the electrode lead or the reference lead and is used for protecting a rear-stage circuit;

the front stage of the blocking capacitor is connected with the lead protection device, and the rear stage of the blocking capacitor is connected with the low-pass filter; the device is used for filtering out a direct current component in an original bioelectricity signal; when the direct current component does not need to be filtered, the direct current component is short-circuited through the controllable switch 1; when an offset driving circuit or an electrode disconnection detection circuit is adopted, the controllable switch 1 is closed, and the blocking capacitor is short-circuited;

the front stage of the low-pass filter is connected with the blocking capacitor module, and the rear stage of the low-pass filter is connected with the power frequency wave trap; the device is used for filtering out unwanted external high-frequency interference signals;

the power frequency wave trap is connected with the low-pass filter and the controllable amplifier; the device is used for filtering out coupled power frequency interference signals in the original bioelectricity signals;

the controllable amplifier is connected with the power frequency wave trap and the analog-to-digital conversion module, and the control end of the controllable amplifier is connected with the controller; the device is used for controllably amplifying the original bioelectric signal, and a control signal of the device is sent by the controller; when the original bioelectric signal does not need to be amplified, the bioelectric signal can be short-circuited through the controllable switch 2; the gain of the controllable switch 2 and the controllable amplifier is controlled by the controller.

5. The bioelectrical signal acquisition system according to claim 1, wherein the synchronous analog-to-digital conversion module and the preprocessing channel are respectively connected to the controller, so as to realize signal synchronous acquisition of a plurality of analog-to-digital conversion devices, and have a unified start signal and clock signal;

when any ADC can realize synchronous acquisition of multiple paths of bioelectricity output signals; the device is provided with a reference signal input port; outputting a path of offset driving signal; the function of detecting broken wires is realized;

each analog-to-digital conversion module is provided with an on-chip or external accurate clock source and a reference source;

when the configuration of a plurality of analog-to-digital conversion modules is the same, more than one ADC is connected in a daisy chain mode so as to save the digital interface of the controller; when different configurations exist in the plurality of analog-to-digital conversion modules, the analog-to-digital conversion modules are respectively connected with the digital interface of the controller according to a standard mode.

6. The bioelectrical signal acquisition system according to claim 1,

the controller is connected with the preprocessing modules, the channel analog-to-digital conversion modules, the memory and the communication interface; the system is used for realizing the overall control of the bioelectricity signal acquisition system, the parameter configuration of each module, the receiving of ADC output signals and the sending of data to an upper computer;

the controller is realized by programming of a DSP, an ARM or an FPGA device.

7. The bioelectrical signal acquisition system according to claim 1,

the communication module is a 5G wireless communication module; the system is used for sending all data acquired by the bioelectricity signal acquisition system to cloud equipment or an upper computer.

8. The bioelectrical signal acquisition system according to claim 7,

the 5G wireless communication module is in communication connection with external equipment with a 5G transceiver module;

the outside plant includes: the system comprises network cloud equipment connected to a 5G network and/or a bioelectricity signal processing computer connected to the 5G network;

the network cloud equipment is used for carrying out instant storage or instant action response on the bioelectricity output signal;

and the bioelectrical signal processing computer is used for carrying out instant processing on the bioelectrical output signal.

9. The bioelectrical signal acquisition system according to any one of claims 1 to 8,

the analog-digital conversion module adopts a unipolar lead mode or a bipolar lead mode; when a unipolar lead is adopted, the P end fed-in signals of each electrode lead connected with the analog-to-digital conversion module use the reference lead fed-in signals as reference potential; when bipolar leads are used, the P end of each electrode lead takes the N end of the corresponding electrode lead as a reference potential.

10. A control method of a multi-channel bioelectric signal acquisition system applied to the multi-channel bioelectric signal acquisition system according to any one of claims 1 to 9, comprising:

setting parameters of a preprocessing circuit and an analog-to-digital conversion module;

controlling the preprocessing channel to preprocess the bioelectrical signals acquired by the N electrode leads or the M reference leads to acquire bioelectrical output signals;

controlling the analog-to-digital conversion module to perform parallel synchronous acquisition and analog-to-digital conversion on the bioelectricity output signals;

and receiving the bioelectrical signal output by the analog-to-digital conversion module.

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