RU2110948C1 - System of recording, storage and examination of electrobiopotentials - Google Patents

Abstract

FIELD: computer engineering. SUBSTANCE: system has cable with set of electrodes, protection elements, controllable switches, test signal forming unit, and difference signal forming unit. System also includes series-connected differential amplifiers and filters, commutator, analog-to-digital converter, microcomputer, galvanic decoupling unit, interface unit, and personal computer. Circuit forming the signal of sinphase component suppression consists of series-connected amplifier, protection element and respective electrode. Electrodes are connected to inputs of difference signal forming unit through protection elements. Unit outputs are connected to unit inputs through contacts of switches. Unit outputs are connected to commutator inputs through amplifiers and filters. Commutator output is connected to analog-to-digital converter input. Outputs of analog-to-digital converter are connected to digit inputs of microcomputer parallel port. Output of microcomputer sequential asynchronous port is connected to input of sequential port of personal computer through galvanic decoupling unit and interface unit. Above-indicated system provides for average speed of information input into computer commensurable with maximum speed of information input through sequential asynchronous port. Information input and processing are free of failures. EFFECT: extended functional capabilities. 1 dwg

Description

 The invention relates to means for creating computer systems for registration, storage and research of electro-biopotentials, and can also be used to create diagnostic systems.

 Known multichannel devices based on microprocessors for the removal of electrical biopotentials and their registration [1]. These devices provide removal, storing of electro-biopotentials and the output of graphical information on a special thermal paper. Depending on the given program, these devices provide automatic analysis of electro-biopotentials and printing of results.

 The disadvantage of these devices is the use of special thermal paper to document the results of the examination, as well as the computer part is rigidly attached to the hardware part of the device. In addition, the memory capacity of such devices is very limited and is not intended for long-term storage of information.

 Known systems for recording, storage and research of electro-biopotentials, containing a personal computer with a monitor and printer, a remote unit for removing electro-biopotentials, a cable with a set of electrodes, a controller in the form of a separate board installed in a computer [2].

 In this system, to increase the speed of entering information into a personal computer, a controller is specially created that matches the remote unit for removing electro-biopotentials from the computer and is connected to the computer motherboard via expansion connectors for desktop computers or via a parallel port for note-book computers. These improvements significantly complicate the information processing scheme, require the involvement of highly qualified specialists.

 Also known are computer systems for recording and storing studies of electro-biopotentials, containing a personal computer with a monitor and printer, a patient cable with a set of electrodes, a unit for removing electrical signals connected to the computer with a cable, and an additional power supply [3].

 In this system, the input of external information into a computer is carried out through a serial asynchronous port of a personal computer. In this case, the input scheme of external information is the simplest, but the average input speed is low. The problem is that in the case of using a serial asynchronous port, information is input into a computer on a single line, sequentially, bit by bit, byte by byte. Moreover, the reception of the next byte can be carried out only if the previous byte or group of bytes is read and processed by the computer. Otherwise, information may be lost. The processing time of information in a computer depends on many factors and may be different at different points in time. To avoid a failure when entering information, the period of time before entering the next piece of information is determined by the maximum time for processing information, which reduces the average speed of input and processing of external information and presentation of results to the user. In this case, the polling frequency of information channels, which should be strictly synchronous, is determined by the maximum time for information transmission and is below the limit provided during exchange via a serial asynchronous port.

 In the proposed system for recording, storing and studying electro-biopotentials, the input of external information is carried out through the serial asynchronous port of the computer, but unlike the known systems, the input speed of external information is close to the maximum provided by the serial asynchronous port without the risk of a failure in processing information in the computer.

 The above is achieved by the fact that in the system of registration, storage and research of electro-biopotentials, containing a personal computer with a printing device, a monitor and a serial asynchronous port, a galvanic isolation unit, an interface unit cable with a set of electrodes, each of which is connected to elements of the protection circuit, in series connected amplifiers and filters, as well as a block for generating differential signals from the electrodes, a block for generating test signals and a signal generating circuit In-phase component, according to the invention, managed keys are introduced that are included one by one in each information channel, a microcomputer with a serial asynchronous port, an analog-to-digital converter (ADC) and a switch, while the inputs of the differential signal generation unit are connected to the outputs of the protection circuit elements of the corresponding electrodes and through the contacts of controlled keys with the corresponding outputs of the test signal generation unit, the outputs of each filter are connected to the outputs of the switch, the output of which is connected the input of the ADC, the outputs of the ADC are connected to the outputs of the discharges of the parallel port of the microcomputer, the information output of the serial asynchronous port of the microcomputer through the galvanic isolation unit and the interface unit is connected to the information input of the serial asynchronous port of the computer, the information output of the serial asynchronous port of the computer through the interface unit and the galvanic isolation unit information input of the serial asynchronous port of the microcomputer and the output of one bit parallel ort microcomputer, and outputs the other discharges the parallel port of the microcomputer are connected respectively to the inputs of circuits zeroing each amplifier and switch control inputs, ADC and driven keys.

 The proposed system of registration, storage and research of electro-biopotentials provides the maximum average speed of input of external information into a computer, close to the maximum speed of input of information via a serial asynchronous port, regardless of the brand of computer and high reliability of processing external information, it is possible to use any computer that has serial asynchronous port, without additional interference with the computer circuit.

 The drawing shows a functional block diagram of the proposed system.

 The system for recording, storage and research of electro-biopotentials contains a set of electrodes 1, each of which is connected via a cable to the input of its protection element 2. Each protection element 2 is connected via a key contact 3 to the corresponding output of the test signal generation unit 4, the output of the protection element 2 is also connected to the corresponding input of the differential signal generating unit 5. Each output of the differential signal generating unit 5 is connected to a separate differential amplifier 6, the output of which is connected to the filter 7. To t he filters amplifiers 6 and 7 is determined by the number of information channels. The output of each filter 7 is connected to the corresponding input of the switch 8, the output of the switch 8 is connected to the input of the ADC 9. The outputs of the ADC 9 are connected to the inputs of the discharges of the parallel port of the microcomputer 10, and the information output of the serial port of the microcomputer 10 through the galvanic isolation unit 11 and the interface unit 12 is connected to the information input of the serial port of the personal computer 13. The information output of the computer 13 through the interface unit 12 and the galvanic isolation unit 11 is connected to the information input of the serial the microcomputer 10 and the input of one discharge of the parallel port of the microcomputer 10, and the outputs of the discharges of the other parallel port of the microcomputer 10 are connected respectively to the inputs of the zeroing circuits of each amplifier 6, the control inputs of the keys 3, switch 8 and AOC 9. The signal generation circuit of the in-phase component consists of interconnected amplifier 14, the protection element 15 and the electrode 16. The input of the amplifier 14 is connected to the block generating differential signals 5.

 The proposed system works as follows.

 Electrobiopotentials from the studied object are removed using electrodes 1, which are pre-installed at the required points of the object. Using command signals from the microcomputer 10, the controlled keys 3 connect the outputs of the test signal generating unit 4 to the corresponding inputs of the differential signal generating unit 5. The system is tested for correct operation of the circuit. The test results are displayed on the computer monitor 13. With the system functioning correctly, the key 3 disconnects the outputs of the test signal generating unit 4 from the differential signal generating unit 5 using the signal from the microcomputer 10. The system circuit is protected from voltage hazardous to electronics by protective elements 2 that are connected to each electrode 1. In the block for generating differential signals 5, signals are generated in accordance with the well-known recommendations of physicians and other specialists. The signals from the outputs of the differential signal generating unit 5 through their amplifiers 6 and filters 7 are fed to the input of the switch 8. From the output of the switch 8, these signals are in a certain order one signal sent to the output of the ADC 9. The priority of the signal to the output of the APC 9 is determined by the control signal, arriving at the control input of the switch 8 from the discharge output of the parallel port of the microcomputer 10. From other outputs of the discharges of the parallel port of the microcomputer 10, the corresponding signals are fed to the control input of the ADC 9 and the inputs of the zeroing circuits amplifiers 6. From the outputs of the ADC 9, the signals are sequentially digitally fed in parallel to the inputs of the discharges of the parallel port of the microcomputer 10, are read and stored in the memory registers of the microcomputer 10. The processor for outputting information from the ADC 9 and entering it in the microcomputer 10 is controlled by the microcomputer 10 itself. The process of sampling signals for the ADC 9 is carried out strictly synchronously according to the timer implemented inside the microcomputer 10. In the memory of the microcomputer, signals are accumulated in digital form for one polling cycle.

 Information is output to a personal computer 13 via a serial asynchronous channel of a microcomputer 10. The first information byte arrives at the serial asynchronous port as soon as a signal from the timer is received in the microcomputer, indicating the beginning of the interrogation cycle of cardiac signals. The output of the remaining bytes of information is carried out only after the signal of readiness of the computer 13 to receive the next byte of information. The signal that the computer 13 is ready to receive the next byte is the start bit of the information byte, which is entered into the microcomputer 10 from the computer 13 through the interface unit 12 and the galvanic isolation unit 11 at the information input of the serial asynchronous port. The microcomputer 10 captures the moment of arrival of the start bit, and as soon as the synchronous exchange with the ADC 9 specified by the microcomputer program ends, the next byte of information from the microcomputer 10 begins to be output to the computer 13 through the galvanic isolation unit 11 and the interface unit 12. In each cycle of the exchange of information of the microcomputer 10 with the computer 13 displays information obtained as a result of a survey of electro-biopotentials in the previous exchange cycle.

 To suppress the common-mode component, which, together with the useful signal, enters the system circuit and degrades the measurement quality of the electro-biopotentials, the system provides a common-mode component suppression signal generation circuit. This circuit contains an amplifier 14, a protection element 15 and an electrode 16. The electrode 16 is installed at a certain point on the object research, and the output of the amplifier 14 is connected to the block generating differential signals 5.

 Introduction to the circuit of a system for recording, storing and researching the electro-biopotentials of switch 8, ADC 9 and microcomputer 10, as well as connecting the outputs of ADC 9 with the inputs of the discharges of the parallel port of microcomputer 10, the information output of the serial port of microcomputer 10 through a galvanic isolation unit 11 and interface unit 12 with an input the serial port of the computer 13, the information output of the computer 13 through the interface unit 12 and the galvanic isolation unit 11 with the information output of the serial port of the microcomputer 10 and the input of one a row of parallel port of microcomputer 10, and discharges of another parallel port of microcomputer 10 with the corresponding input of the zeroing circuit of each amplifier 6 and control inputs of switch 8, ADC 9 and controlled keys 3, allow to minimize the idle time period of each information exchange cycle between microcomputer 10 and computer 13 This increases the average speed of information transfer, bringing it closer to the maximum speed for a serial asynchronous port, without fear of failures.

 The connection of the inputs of the differential signal generating unit 5 with the electrodes 1 and with the outputs of the test signal generating unit 4 through the contacts of the controlled keys 3 allows you to create high-quality service during operation.

 It should be noted that the structure of the proposed system allows you to build capabilities by building software without changing hardware and refuse an additional power source.

 Literature.

 1. Electronic devices for neurophysiological studies. / Collection of articles edited by Yu.V. Krylova. M.: Nauka, 1992, p. 37-39.

 2. There, p. 40-41.

 3. Catalog of the company "Actual Medical Technologies" (AMT), Italy, p. 11, EASY system, 1995 (the prospectus is published in the journal Biology N 11, 1995, p.31).

Claims (1)

 A system for recording, storing and researching electro-biopotentials, which contains a personal computer with a printing device, a monitor and a serial asynchronous port, an galvanic isolation unit, an interface unit, a cable with a set of electrodes, each of which is connected to elements of a protection circuit, amplifiers and filters are connected separately in series for each information channel, as well as a block for generating differential signals from electrodes, a common-mode component suppression circuit, and a test generation block signals, characterized in that it contains managed keys that are included one by one in each information channel, a microcomputer, an analog-to-digital converter and a switch, while the inputs of the differential signal generation unit are connected to the outputs of the elements of the protection circuit of the corresponding electrode and through the contacts of the controlled keys - with the corresponding outputs of the test signal generation unit, the outputs of each filter are connected to the corresponding input of the switch, the output of which is connected to the input of the analog-to-digital converter When firing, the outputs of the analog-to-digital converter are connected to the inputs of the discharges of the parallel port of the microcomputer, the information output of the serial asynchronous port of the microcomputer through the galvanic isolation unit and the interface unit is connected to the information input of the serial asynchronous port of the computer, the information output of the serial asynchronous port of the computer through the galvanic isolation unit and the interface unit connected to the information input of the serial asynchronous port of the microcomputer and the input of one bit the poison of the parallel port of the microcomputer, and the outputs of the discharges of another parallel port of the microcomputer are connected respectively to the inputs of the nulling circuits of each amplifier and the control inputs of the switch, analog-to-digital converter, and controlled keys.