KR20030070315A - The Non-Contact Cardiovascular-Respiratory Analysis System using the 60GHz Microwave - Google Patents

Abstract

PURPOSE: A contactless type cardiovascular-beating signal analyzer using a microwave of 60 GHz is provided to measure the beating of the heart transmitted to the outer skin by using a phase difference according to the surface vibration. CONSTITUTION: A contactless type cardiovascular-beating signal analyzer using a microwave of 60 GHz includes an oscillation unit. The oscillation unit is used for irradiating the microwave of 60 GHz to a human body. The contactless type cardiovascular-beating signal analyzer further includes a receiver. The receiver is used for receiving the microwave of 60 GHz. The contactless type cardiovascular-beating signal analyzer further includes a filter unit. The filter unit is used for removing the vibration from a surface of skin.

Description

The Non-Contact Cardiovascular-Respiratory Analysis System using the 60GHz Microwave}

What is very important in maintaining the life of the living thing is to keep the blood pressure in the body constant, which is why the living thing has various mechanisms. In particular, the circulatory system to maintain constant blood pressure in the body and to supply nutrients to each organ is the most important means for maintaining the life of life, and the nervous system that plays the most dominant role in the circulatory system is the sympathetic and parasympathetic nervous system of the autonomic nervous system. to be. Therefore, in order to evaluate the adaptability to the external environment of the human body, that is, the health state, in relation to the maintenance of the homeostasis of the human body, the analysis and evaluation of the autonomic nervous system has an important meaning.

There was no good way to test autonomic activity in the human body. It is generally invasive and changes over time and lacks reliability. Recently, however, a method of interpreting the contraction cycle of the heart as a spectrum has emerged, and asg has increased the reliability of this method through international literature and research publications. By analyzing the heart's contraction cycle, heart rate and blood pressure, or the relationship between heart rate and respiration, hidden functions of the autonomic nervous system are being studied.

Conventional cardiac signal measurement method using the impedance of the cardiac output measuring device (Fig. 2), and recently, a method of measuring the heartbeat in a non-contact method using a microwave of 2GHz in the United States has been announced.

In the case of the cardiac output measuring apparatus using the impedance of FIG. 2, a signal is measured by attaching an electrode to a neck and chest circumference, which is easy to attach the electrode to the heart. The problem with this method is that the operation in the open state of the chest or uncomfortable to do in the naked state.

Therefore, in order to solve the above problem, the position of the electrode was attached to the arm and leg as shown in FIG.

In addition, another problem is that the patient measured the signal in a state of no movement in the lying position to measure the C / O, but if the continuous monitoring of the patient needs to develop a device that can respond to the movement of the patient, A small monitor capable of detecting a heart rate during exercise by attaching a sensor to detect a heartbeat signal on the chest has been developed and is commercially available (FIG. 3).

However, the heart rate monitor is not used to measure the detailed elements of the heart rate signal, but is only used for the purpose of managing the exercise effect of an athlete or a sports lover simply by measuring the number of beats. At present, no heart rate monitor has been researched or developed in Korea. In other countries, large sports distributors have competitively developed and marketed a heart rate monitor. However, all of these products are equipped with a signal measuring part (pulse sensor) on the chest, a monitor on the wrist, and a movement, and thus are defenseless against the pain caused by drastic exercise or the physical characteristics of a woman.

Furthermore, the analysis of respiratory signals has not yet taken place at the same time.

In the present invention, an electromagnetic wave having a total reflection at the epidermal part of the human body uses electromagnetic waves when a wavelength of several mm (60 mm, λ = 5 mm) is harmless to the human body without using a conventional electrode. . The heart rate of the subject is detected by using the characteristics of the plane wave moving through the space reflected from the surface and the phase difference caused by the surface vibration. The non-contact cardiovascular-respiratory signal analysis device according to the present invention measures the contraction activity of the heart to be transmitted to the external epidermis, so that the contraction of the heart can be detected even if there is a simple obstruction between the sensor and the epidermis. There is an advantage. In addition, since the projection is performed by the impulse method instead of the continuous electromagnetic waves, erroneous detection can be prevented by adjusting the detection range.

The contactless cardiovascular-respiratory signal measuring device consists of a radio transmitter, an interface card that connects a notebook and radio transmitter, a power supply, and a program for measuring, managing and analyzing stored data, and displaying a signal on the monitor. have. The basic operating principle of a radio transmitter is based on the Doppler effect, that is, the small displacement velocity measurement of the projected object (ie, the human breast surface).

The main source of cardiac vibration sources in the cardiovascular system is the regular intestinal flow of blood from the growth of the aorta, which results in the appearance of fluid wave pressure. It is transmitted through blood vessels and is called a pulse. The pulse thus reflects activities related to many structural and functional elements of the heart and cardiovascular system and affects the autonomic nervous system and muscle system. Therefore, the measuring device according to the present invention can be measured remotely the fine surface vibration of the chest associated with the cycle of heart contraction and expansion can be said to have high utility in many clinically.

The result of the measurement is a periodic signal that reflects cardiac activity. The computer automatically evaluates the activity flow for the heart and cardiovascular system, and can evaluate changes in the autonomic nervous system for external physical and mental loads. The measuring device can be measured even when wearing clothes or shoes in a non-contact manner. The meter is designed to maintain very high sensitivity and has the ability to record in real time, allowing first aid. It also has time durability and excellent reproducibility and accuracy of measurements. In addition, the measuring device operates at radio wavelengths in the ultra-high frequency cross-section and has no detrimental effect on the subject. The technical specifications of the non-contact cardiovascular-respiratory signal measuring device developed in this study are shown in Table 1 below, and the configuration diagrams are shown in FIGS. 4 and 5. 6 shows the appearance of the measuring device.

The contactless cardiovascular-respiratory signal measuring device is composed of a device interface part consisting of an ultra-high frequency block, a medium frequency block, a low frequency block, and an analog-to-digital converter. Finally, the measured phase difference signal is recorded on the notebook through the parallel port connection cable, where further deep combinations and analysis are performed, the measured and calculated variables are evaluated graphically and graphically, and the diagnosis results are automatically segmented and evaluated. do.

Ultra-high frequency blocks have a metallic monolithic structure and are a power separator combined with metal parts of antennas, fundamental and signal channel oscillators, microwave mixers, air ducts, directed couplers and wave guides. separator).

The mid-frequency block consists of a medium frequency oscillator phase detector of the fundamental channel and the signal channel. The low frequency block consists of an analog amplification circuit consisting of a basic channel and a signal channel, an output signal filter, a mixed oscillator, and an analog-to-digital converter which is essential for transmitting signals to a PC and combining and analyzing future measurement results. The current supply can be supplied at 220V / 110V, 60 Hz or a battery can be used.

Figure 1 C / O meter for contactless remote monitoring

Figure 2 conventional impedance C / O meter

3 Example of use of a commercial heart rate monitor

4 is a block diagram of a non-contact cardiovascular-breathing signal measuring device

5 Interface Block Diagram (A / D and ADSP 2105)

6 the appearance of the fabricated system

7 is a schematic diagram of a non-contact cardiovascular-respiratory signal analysis device

7 is a schematic diagram of a non-contact cardiovascular-respiratory signal analysis device according to the present invention. As shown in the figure, the present invention consists of an impulse generator and receiver, a reflected wave detector, and a transceiver capable of irradiating and receiving microwaves on the human body, and processing the digital signal to analyze the signal detected by the human body in a diagnostic algorithm. (DSP) and filter to remove micro vibrations on the surface.

The study of new technologies developed through this study is a means to improve the accuracy of cardiovascular signals obtained by subjects and to provide technical methods of preventing many kinds of adult diseases. Non-contact irradiation method using electromagnetic waves and signals as a measurement method can obtain the cardiovascular parameters measured in the subject, this method is very safe. These methods also exhibit high sensitivity to measured physical variables and use current computer technology. In addition, it is possible to obtain the respiratory cycle signal occurring in the local part of the lung tissue in real time, to calculate the parameters of external respiratory function, and to obtain information about the heart rate from a distance. In addition, based on the data obtained in this way, the functional and mental state of the subject can be evaluated at a distance in real time.

In patients with stroke, diabetes, or spinal cord injuries that are predicted to have autonomic nervous system abnormalities, the autonomic nervous system may be associated with daily behavior and daily variation in the disease. The development of predictive values for prognosis, the effects of therapeutic intervention, the prediction of serious cardiovascular adverse events and therapeutic intervention in spinal cord injury patients can be identified.

In addition, through the efficient remote management of heart rate and breathing, it is possible to contribute to the national physical strength by providing reasonable data for basic fitness training of athletes.

Claims (3)

Oscillator designed to irradiate human body with 60 GHz fine microwave Receiving apparatus capable of receiving the fine microwave of claim 1 Filter device that can remove fine vibrations on the skin surface