SU1246985A1 - Apparatus for monitoring external respiration - Google Patents

Description

The invention relates to medical technology, in particular, to devices for measuring and recording the depth and respiration rate of humans and animals. 5

The purpose of the invention is to increase the noise immunity of the device when an object moves in the process of investigation,

Fig, 1 shows the structural 10 scheme of the device; in fig. 2 - constructive implementation of a two-input pass-through resonator.

The device contains sequential 12A69852

rum 23. The voltage from source 16 is supplied to detector diode 5 through. LPF 9 and the rod 20, 24 is a mechanism for restructuring the resonator 4.

The device works as follows.

In the initial state, with the attenuator 3 fully inserted, the resonator 4 (or generator 8) is adjusted in frequency so that there is no signal on the indicator 13 "When the attenuator 3 is opened and-when the microwave signal hits the patient's chest, the reflected signal through antenna 1, phase shifter 2 ,

the antenna 1), the phased array 15 Lp-3 attenuator again enters the resonator 2, the first attenuator 3, the two-input resonator 4 with the detector 5 installed in it, made on a semiconductor diode, a valve 6, the second attenuator 7 and the generator 8 20 microwave frequencies; the resonator 4 through the third low-frequency filter 9 (low pass filter) and the first low frequency filter 10 (low pass filter), including resistor 11 and capacitor 12, is connected to amplitude indicator 13, the low pass filter 9 is also connected through the second low pass filter 14 (low pass filter 14 ) with indicator 15, part 4 and changes its mode of operation — the frequency of generations and the current through the semiconductor detector diode 5 are changed. The intensity (magnitude) of 1 14 will depend on the frequency and depth of breathing and can be fixed by the indicators 13 , 15, With high q of coaxial resonator 4 (this is provided by the method of selecting the hole 21)

Di-1

frequency changes

-five.

and changes

semiconductor diode conductance

The detector 5 through the low-pass filter 9 and the resistor 11 is connected to the source 16 of the direct voltage of the low-pass filter 14 is a broadband circuit. Antenna 1 is made in the form of a pyramidal horn with an aspect ratio of 1: 2.3-1: 2.5, which ensures the minimum input to the device of signals reflected from objects located near the object under study.

I

The double-entry resonator 4 (Fig. 2) is coaxial and is formed by the inner surface of sleeve 17, a fixed end wall 18, an end face of a movable adjustment body 19 with a semiconductor anode of detector 5 attached to it, and a central rod 20 passing through the communication hole 21 in the end wall 18, combined with the wide wall of the waveguide 22, the Moving body 19 of the adjustment is made in the form of a cylindrical contactless waveguide short circuit, and the fixed end wall 18 has g thickness not larger its 1/4 of the minimum working wavelength of the resonator 4. A cylindrical contactless waveguide shortcircuit connected to the radio antenna Lp-3 again falls into the resonator

torus 4 and changes its mode of operation — the oscillation frequency and the current through the semiconductor diode of the detector 5 vary. The intensity (magnitude) of ignition14 will depend on the frequency and depth of breathing and can be fixed at indicators 13, 15, high quality of the coaxial resonator 4 (this is provided by the method of selecting the aperture 21)

Di-1

frequency changes

-five.

and changes

the Lp-3 attenuator again falls into the reson-

semiconductor diode conductance

DS

- from moving the chest

 - UO

will be related by:

- -2 - (rjcos4 (1)

LO

 i

Tijt

sin

(2)

2-uJ

where V arglrj - -.; - „+ V (t-tj;

GN | - U. uJp .c -

g ..

modulus of reflection coefficient; magnetic, magnitude from the chest;

external quality factor of the resonator;

resonant frequency; wave speed (C 3 10 cm-s-); the distance between the diode and the initial position of the chest (t t.)

uG

GL

LO GL / G - 0, 0 - corresponds to the case when the attenuator 3 is fully entered, there are no reflections from the chest.

The change in current through the diode of the detector 5 is synchronous with the change in the position of the chest (or the cardiac impulse area), and the amplitude of the change is proportional to the path traveled by the moving surface V (t - t).

uuJ

Minimum frequency changes

uJ.

significant changes in current

waves is equal to y and

and accordingly. It means.

are reached at the points where the phase is reflected by the scientific research institute of the 4 O or. MaximalTa

The voltage across the resistor 11 is reached at the points where the reflection phase F is.

/ S

that the patient can occupy the most physiological normal breathing position, and the high sensitivity of the device, high accuracy in determining the respiration parameters can be ensured by adjusting the phase shifter 2 without changing the relative position of the patient and the device. The semiconductor diode of the detector 5 (Fig. 1) receives a signal from an ultra high frequency generator 8. Therefore, the diode of the detector 5 displaces the signal reflected from the chest and the signal from the generator 8 and the low pass filter 14 produces a signal

ten

15

- five

20

25

 equal to the frequency of change in the position of the chest. In order for the frequency changes of the resonator 4 to track changes in the position of the chest, it is necessary to avoid the occurrence of forced synchronization, i.e. It is necessary to satisfy the relation:

 T / Pr-Q.,

where P, P is the power of the signals from the resonator 4 and generator 8, respectively.

The signal level corresponding to these conditions is regulated by the attenuator 7, and the valve 6 prevents the signals from the resonator 4 from entering the generator 8 and ensures the stability of its operation.

Such interconnection and interdependence of features ensures the nofofunctionality of the device, allows simultaneous recording of the frequency and depth of respiration of both humans and animals, as well as the frequency of heartbeat and pulse, if we use the resonator 4 and the generator 8, operating in the short-wave part of the millimeter range .

23

VNITI Order 4039/4

Circulation 660

Subscription

Random polygons pr-tie, Uzhgorod, st. Project, 4

Circulation 660

Subscription

 Uzhgorod, st. Project, 4

Claims (1)

A DEVICE FOR EXTERNAL RESPIRATION CONTROL, comprising an antenna, microwave generator, amplitude and frequency detectors, characterized in that, in order to increase the noise immunity of the device when the object is moving during the study, a second low-pass filter and series-connected phase shifter, the first attenuator, are introduced into it a two-input resonator in which the detector and the third low-pass filter are located, the valve and the second attenuator connected to the microwave generator, the input of the phase shifter is connected with an antenna, a two-input pass-through resonator is connected to the amplitude indicator through the third and first low-pass filters and through the third and second low-pass filters of FIG. 1 SU. ,, 1246985