RF MICROWAVE CORE TEMPERATURE SYSTEM HAVING RF RECEIVER MODULE TO DETECT CORE TEMPERATURE
20220192504 · 2022-06-23
Assignee
Inventors
Cpc classification
G01K11/006
PHYSICS
A61B5/05
HUMAN NECESSITIES
A61B5/7445
HUMAN NECESSITIES
A61B5/7225
HUMAN NECESSITIES
A61B5/002
HUMAN NECESSITIES
A61B5/7435
HUMAN NECESSITIES
A61B5/01
HUMAN NECESSITIES
International classification
A61B5/01
HUMAN NECESSITIES
A61B5/00
HUMAN NECESSITIES
A61B5/05
HUMAN NECESSITIES
G01K1/02
PHYSICS
Abstract
Provided are a radio frequency (RF) receiver module for sensing core body temperature and an RF microwave core body thermometer system having the same. The RF receiver module for sensing core body temperature and the RF microwave core body thermometer having the same include: an RF contact-type patch antenna attached to a body part to sense the core body temperature; an RF receiver circuit unit attached to the body part to receive any one RF frequency signal within an RF frequency range of 1 to 10 GHz through the RF contact-type patch antenna for sensing core body temperature; and an interface circuit unit for connecting the RF receiver circuit unit to a control unit of a microprocessor control unit.
Claims
1. A radio frequency (RF) receiver module for sensing core body temperature, the RF receiver module being included in an RF microwave core body thermometer, the module comprising: an RF contact-type patch antenna attached to a human part to sense the core body temperature of the human body; an RF receiver circuit unit to receive any one RF frequency signal within a frequency range of 1 to 10 GHz through the RF contact-type patch antenna for sensing core body temperature; and an interface circuit unit for connecting the RF receiver circuit unit to a control unit of a microprocessor control unit.
2. The module according to claim 1, wherein the RF receiver module for sensing core body temperature is attached to the human body and receives any one RF frequency signal among RF frequencies of 1 to 10 GHz except for 1.4 GHz and 2.7 GHz to sense the core body temperature.
3. The module according to claim 1, wherein a specific RF frequency of the RF receiver module for sensing the core body temperature measures the core body temperature of a human body by using any one RF frequency of 1.6, 1.7, 1.8, 1.9, and 2.0 GHz frequencies.
4. The module according to claim 1, wherein the RF receiver circuit unit includes: a low-noise amplifier (LNA) stage for receiving an RF frequency signal from the RF contact-type patch antenna, removing noise of a low voltage signal within a frequency range of 1 to 10 GHz, and amplifying the low voltage signal; a variable attenuator connected to the low-noise amplifier stage to remove noise around the center frequency by attenuating the noise of the signal, and amplify the signal; two down mixers branched from the variable attenuator to down-convert the GHz frequency into an IF band frequency within a range of 50 to 200 MHz and improve sensitivity; two IF buffers connected to the two down mixers respectively to provide clean signals (I, Q) respectively by removing noise and resistance components of the down-converted IF frequencies; an on-chip internal oscillator (IQ LO generator) for oscillating a signal to make an amplitude-modulated sine wave in-phase and quadrature, and providing an in-phase signal LO_I and its quadrature signal LO_Q of a local oscillator LO; and an off-chip external oscillator (Ext. LO) for providing an oscillation signal from the outside of the chip so that clock noise may not pass through from the outside of the chip.
5. The module according to claim 1, wherein the RF receiver module for sensing core body temperature, an MMIC filter chip is manufactured in the RF receiver module for a core body thermometer on a silicon (Si) substrate by using a CMOS process.
6. The module according to claim 4, wherein the interface circuit unit includes: an A/D converter for receiving the in-phase signal LO_I and its quadrature signal LO_Q of the local oscillator LO received from the RF receiver circuit unit, and A/D converting the signals; and a temperature converter for converting a heat radiation signal into a core body temperature inside a human body corresponding to a digital value measured by power corresponding to an RF frequency by using a basic principle that radiation intensity linearly changes at an RF frequency lower than 10 GHz with respect to the core body temperature inside a human body by a Plank and Rayleigh Jeans approximation law, so that the heat radiation signal radiated from the inside under a skin of the human body and transferred to a surface of the skin may be converted into a body temperature value.
7. A radio frequency (RF) microwave core body thermometer system provided with an RF receiver module for sensing core body temperature, the thermometer comprising: an RF receiver module for receiving any one RF frequency signal within an RF frequency range of 1 to 10 GHz except for 1.4 GHz and 2.7 GHz, and sensing the core body temperature; and an RF microwave core body thermometer connected to an interface circuit unit of the RF receiver module in order to display a core body temperature inside a human body measured by power corresponding to an RF frequency by using a basic principle that radiation intensity linearly changes at an RF frequency lower than 10 GHz with respect to a core body temperature inside the human body by a Plank and Rayleigh Jeans approximation law by using the received RF frequency signal, on an organic light-emitting diode (OLED) display.
8. The thermometer system according to claim 7, wherein in the RF receiver module for sensing core body temperature, an MMIC chip is manufactured on a silicon (Si) substrate for a core body thermometer using a CMOS process.
9. The thermometer system according to claim 7, wherein the RF microwave core body thermometer includes: a microprocessor control unit connected to the interface circuit unit of the RF receiver module to control to convert a heat radiation signal radiated from the inside under the skin of a human body and transferred to the surface of the skin into a core body temperature value using a correlation between heat radiation power and bio-thermodynamic temperature within an RF frequency range of 1 to 10 GHz, and display a core body temperature inside the human body measured by the power corresponding to the RF frequency on a display by using the basic principle that radiation intensity linearly changes at an RF frequency lower than 10 GHz with respect to the core body temperature inside the human body by the Plank and Rayleigh Jeans approximation law; a communication unit connected to the microprocessor control unit; a button input unit including a power ON/OFF button of a button input unit of a display, and a measurement shot button; a menu button control unit connected to the button input unit to operate by the button; an OLED display control unit and a color OLED display connected to the microprocessor controller to display the measured core body temperature of a human body; and a power control unit, a secondary battery, a charging circuit unit, and a USB charging connector.
10. The thermometer system according to claim 9, further comprising an LED indicator connected to the microprocessor control unit and provided at a pistol-shaped entrance.
11. The thermometer system according to claim 7, further comprising: a handy-type body equipped with the RF microwave core body thermometer having the RF receiver module, connected to an interface circuit (PCB) of the RF receiver module, driven by a lithium polymer battery, included with an LED indicator at the pistol-shaped entrance facing upward from the horizontal line at an angle of 30° or lower, included with a color OLED display and a button input unit on the top surface, and included with a measurement shot button of the handle of the pistol-shaped handy-type body; and a charging cradle that mounts the handy-type body equipped with the RF microwave core body thermometer, is provided with an AC-DC converter, and is connected to an AC power plug connected a power cable.
12. The thermometer system according to claim 7, further comprising a user terminal directly connected from a communication unit of the RF microwave core body thermometer through Wi-Fi or Bluetooth communication, wherein the user terminal displays core body temperature inside a human body measured by the power corresponding to the RF frequency.
13. The thermometer system according to claim 7, further comprising: a server for storing core body temperature inside a human body measured according to the power corresponding to the RF frequency from a communication unit of the RF microwave core body thermometer; and a user terminal connected to the server through a wired/wireless communication network to display the core body temperature inside a human body stored in the server which is measured by the power corresponding to the RF frequency.
14. The thermometer system according to claim 13, wherein the user terminal uses any one of a smart phone, a computer, a personal computer (PC), a tablet PC, or an embedded system for a medical device.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION
[0071] Hereinafter, the configuration and operation of the example embodiments of the present invention will be described in detail with reference to the accompanying drawings.
[0072] The present invention manufactures one MIMIC chip on a silicon (Si) substrate by using a CMOS process as one chip in the RF receiver module for a core body thermometer, and provides an RF microwave core body thermometer equipped with an RF receiver module (RF/IF Si MMIC receiver module) for sensing core body temperature, which measures core body temperature of a human body by using any one RF frequency signal within an RF frequency range of 1 to 10 GHz.
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[0075] The RF microwave core body thermometer technique of the present invention uses a technique of converting a heat radiation signal radiated from the inside under the skin of a human body and transferred to the surface of the skin into a body temperature value by using a correlation between heat radiation power and bio-thermodynamic temperature.
[0076] Any one RF microwave frequency in an RF frequency range of 1 to 10 GHz is used to measure core body temperature inside a biological tissue of a human body, and in the RF microwave frequency range, electromagnetic waves penetrate up to 5 cm from the surface of skin tissue.
[0077] Within the RF frequency range of 1 to 10 GHz, core body temperature inside a human body may be measured by the power corresponding to the RF frequency by using the basic principle that radiation intensity changes almost linearly at an RF frequency lower than 10 GHz with respect to the core body temperature by the Plank and Rayleigh Jeans approximation law.
[0078] The RF receiver module of the RF microwave core body thermometer is a wearable core body thermometer attached to a human body, includes an RF contact-type patch antenna (near-field probe on skin), a radiometer, an ADC, a control unit, a storage unit, and a wireless transmitter, and measures core body temperature of a human body using any one RF frequency signal within an RF frequency range of 1 to 10 GHz.
[0079] In the embodiment, any one RF frequency of 1.6, 1.7, 1.8, 1.9, and 2.0 GHz frequencies is used as a specific RF frequency of the RF microwave core body thermometer.
[0080]
[0081] Since microwave radiometers may sense temperature at a depth of up to 3 to 7 cm below the skin surface at microwave frequencies and determine a subsurface temperature, they are practical in the medical field. They are first applied to subsurface thermography.
[0082] Microwave radiometry for non-invasive temperature measurements is based on near-field power reception and makes it possible to achieve the spatial resolution and sensing depth required in various medical application fields including cancer detection.
[0083] Monitoring drug delivery for cancer treatment, hyperthermia temperature control, hypothermic neural rescue of infants suffering from hypoxia-ischemia, and detection of vesicoureteral reflux in children are used for non-invasive near-field radiometric measurements. As a non-invasive microwave thermometer detects arthritis, a method of measuring elevated joint temperature also has been investigated.
[0084] Antenna temperature of an object in near-field within a few centimeters using radiometry is a weighted average of the temperature of the objects close to the antenna. Therefore, weighting functions (WFs) are used to define an antenna.
[0085] A radiometer is a device for measuring incoherent radiation.
Power density P=kT.sub.phyB
Temperature T=T.sub.B×e(brightness temperature T.sub.B×emissivity e)
[0086] Here, P is power density, T.sub.B is brightness temperature emitted from an object, T.sub.phy is physical temperature, e is emissivity of the object, k is the Boltzmann's constant, and B is the bandwidth of the power density.
[0087] A radiometer is a device for measuring incoherent radiation, and Matter emits electromagnetic energy based on temperature of all directions with spectral brightness described by Planck's blackbody radiation law.
[0088] Here, his Planck's constant (6.63×10.sup.−34 J.Math.sec), c is the speed of light in vacuum (m/sec), k is Boltzmann's constant (1.38×10.sup.−23 J/K), and T is Kelvin temperature.
[0089] Referring to
[0090] The brightness for microwave is different from the optical terminology of radiance.
[0091] At a low frequency of hf/kT<<1, as a result, quantity (e.sup.hf/kT−1) may be approximated by the truncated Taylor series like (e.sup.x−1≈x). The Planck's blackbody radiation law reduces the low frequency approximation known as Rayleigh-Jeans law.
[0092] In the case of body temperature (≈310K), the Rayleigh-Jeans law deviates from the Planck's law by less than 1%. Since it is 127 GHz in maximum, it is effective in the microwave frequency range. Radiant electromagnetic energy may be received by an antenna that converts electromagnetic energy propagated as a guided wave of a transmission line in a free space by the Planck's blackbody radiation law.
[0093] Since the antenna is polarized and electromagnetic radiation has independent polarizations, the power received by the antenna from the spatial distribution of the spectral brightness given by Bf(θ,φ) will be only half of the total incident power.
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[0095] A product of the RF microwave core body thermometer includes an RF microwave core body thermometer 90 to 99 connected to the RF receiver module 70 for sensing core body temperature; a handy-type body equipped with the RF microwave core body thermometer 90 to 99 having the RF receiver module 70, connected to an interface circuit (PCB) of the RF receiver module 70, driven by a lithium polymer battery 97, included with an LED indicator 99-4 at the pistol-shaped entrance facing upward from the horizontal line at an angle of 30° or lower, included with a color OLED display 95 and a button input unit 92-3 on the top surface, and included with a measurement shot button 92-1 of the handle 101 of the pistol-shaped handy-type body; and a charging cradle 107 that mounts the handy-type body equipped with the RF microwave core body thermometer 90 to 99, is provided with an AC-DC converter, and is connected to an AC power plug to which an AC power line is connected.
[0096] A prototype of a handy-type RF microwave core body thermometer that can drive the “RF microwave transmission module”, which is the core technology of the RF microwave core body thermometer, using a secondary battery (e.g., a lithium polymer battery) has been manufactured to secure base technology for commercialization.
[0097] An infrared thermometer is limited to measurement of temperature of skin surface such as the forehead, the back of a hand, the temple or the like, whereas the RF microwave core body thermometer may measure core body temperature in most of ranges including a chest, sides, and legs, and the center portion of a torso, and may measure both the front and rear sides of a body.
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[0099] The RF microwave core body thermometer provided with an RF receiver module for sensing core body temperature includes: an RF receiver module 70 for sensing core body temperature, which includes an RF receiver circuit unit 72 attached to a human body part to receive any one RF frequency signal within a frequency range of 1 to 10 GHz through an RF contact-type patch antenna 71 for sensing core body temperature, and an interface circuit unit 73; an RF microwave core body thermometer 90-99 connected to the interface circuit unit 73 of the RF receiver module 70 for sensing core body temperature in order to display the core body temperature of a human body measured by the power (watt (W), brightness) corresponding to the RF frequency using the basic principle that radiation intensity changes almost linearly at an RF frequency lower than 10 GHz with respect to the core body temperature inside the human body by the Plank and Rayleigh Jeans approximation law by using any one RF frequency signal within a frequency range of 1 to 10 GHz, on an OLED display.
[0100] The RF receiver module 70 for sensing core body temperature includes: an RF contact-type patch antenna 71 attached to a human body part to receive a heat radiation signal radiated from the inside under the skin of a human body and transferred to the surface of the skin; an RF receiver circuit unit 72 for receiving any one RF frequency signal within an RF frequency range of 1 to 10 GHz through the RF contact-type patch antenna 71; and an interface circuit unit 73 through which the RF receiver circuit unit 72 is connected to a microprocessor control unit 90.
[0101] The RF microwave core body thermometer 90 to 99 includes a microprocessor control unit 90, a communication unit 91, a shot button input unit 92, a menu button control unit 93, an OLED display control unit 94, a color OLED display 95, a power control unit 96, a lithium polymer battery 97, a charging circuit unit 98, and a USB charging connector 99.
[0102] The RF microwave core body thermometer includes: a microprocessor control unit 90 connected to the interface circuit unit 73 of the RF receiver module 70 to control to convert a heat radiation signal radiated from the inside under the skin of a human body and transferred to the surface of the skin into a core body temperature value using a correlation between heat radiation power and bio-thermodynamic temperature within an RF frequency range of 1 to 10 GHz, and display a core body temperature inside the human body measured by the power corresponding to the RF frequency on a display using the basic principle that radiation intensity changes almost linearly at an RF frequency lower than 10 GHz with respect to the core body temperature inside the human body by the Plank and Rayleigh Jeans approximation law; a button input unit 92 including a power ON/OFF button of the button input unit 92-3 of the display, and a measurement shot button 92-1; a menu button control unit 93 connected to the button input unit 92 to operate by the button; an OLED display control unit 94 and a color OLED display 95 connected to the microprocessor controller 90 to display the measured core body temperature of a human body; and a power control unit 96, a lithium polymer battery 97, a charging circuit unit 98, and a USB charging connector 99
[0103] Additionally or optionally, the RF microwave core body thermometer system further includes an LED indicator 99-4 connected to the microprocessor control unit 90 and provided at the pistol-shaped entrance.
[0104] The button input unit 92 includes a measurement shot button 92-1 pulled with an index finger from the hook of the pistol-shaped handle; and a button input unit 92-3 of a display provided adjacent to a color OLED display 95.
[0105] The communication unit 91 of the RF microwave core body thermometer 90 to 99 includes at least one communication unit among a Bluetooth communication unit, a Wi-Fi communication unit, an LTE 4G communication unit or 5G communication unit, and an IoT communication unit (LoRa RF communication unit or NB-IoT communication unit).
[0106] In addition, the RF microwave core body thermometer system further includes a user terminal 110 directly connected from the communication unit 91 of the RF microwave core body thermometer 90 to 99 through Wi-Fi or Bluetooth communication, and the user terminal displays core body temperature inside a human body measured by the power corresponding to the RF frequency. The user terminal 110 generates an alarm when the core body temperature exceeds a preset normal core body temperature by statistical data on each measurement part of a human body, and transmits a message to an emergency room system when the core body temperature excessively exceeds a preset core body temperature value.
[0107] The RF microwave core body thermometer system further includes: a server 100 for storing core body temperature inside a human body measured according to the power corresponding to the RF frequency received from the communication unit 91 of the RF microwave core body thermometer 90 to 99 through Wi-Fi, LTE 4G or 5G communication; and a user terminal 110 connected to the server 100 through a wired/wireless communication network (LAN, Ethernet, Wi-Fi, LTE 4G or 5G network) to display the core body temperature inside a human body stored in the server 100 and measured by the power corresponding to the RF frequency.
[0108] Any one among a smart phone, a tablet PC, a computer (PC), and an embedded system for a medical device is used as the user terminal 110.
[0109] An RF microwave frequency in a range of 1 to 10 GHz is used to measure the core body temperature inside a biological tissue of a human body, and in the RF microwave frequency range, electromagnetic waves penetrate up to 3 to 7 Cm from the surface of skin tissue.
[0110] The RF microwave deep thermometer may measure A core body temperature inside a human body by the power (brightness) corresponding to the RF frequency using the basic principle that radiation intensity changes almost linearly at an RF frequency lower than 10 GHz with respect to the temperature inside the human body (core body temperature) by the Plank and Rayleigh Jeans approximation law so that a heat radiation signal radiated from the inside under the skin of the human body and transferred to the surface of the skin may be converted into a body temperature value by using a correlation between heat radiation power and bio-thermodynamic temperature within an RF frequency range of 1 to 10 GHz.
[0111] The RF receiver module of the RF microwave core body thermometer is a wearable core body thermometer attached to a human body, which includes an RF contact-type antenna (near-field probe on skin), a radiometer, an ADC, a control unit, a storage unit, and wireless transmitter, and measures core body temperature of a human body using an RF frequency signal within a frequency range of 1 to 10 GHz.
[0112] In the embodiment, any one RF frequency of 1.6, 1.7, 1.8, 1.9, and 2.0 GHz frequencies is used as a specific RF frequency of the RF microwave core body thermometer.
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[0114] The RF receiver module of the microwave core body thermometer is implemented on a silicon substrate as a CMOS chip, and the RF receiver module for sensing core body temperature includes: an RF contact-type patch antenna 71 attached to a human body to receive a heat radiation signal radiated from the inside under the skin of the human body and transferred to the surface of the skin; an RF receiver circuit unit 72; and an interface circuit unit 73.
[0115] The RF receiver circuit unit 72 includes: a low-noise amplifier stage (LNA stage) for receiving an RF frequency signal from the RF contact-type patch antenna 71, removing, for example, noise of a low voltage signal of 1.5 GHz within a frequency range of 1 to 10 GHz, and amplifying the low voltage signal; a variable attenuator connected to the low-noise amplifier stage to remove noise around the center frequency by attenuating the noise of the signal, and amplify the signal; two down mixers branched from the variable attenuator to down-convert the GHz frequency to an IF band frequency within a range of 50 to 200 MHz and improve sensitivity; two IF buffers connected to the two down mixers respectively to provide clean signals (I, Q) respectively by removing noise and resistance components of the down-converted IF frequencies; an on-chip oscillator (IQ LO generator) for oscillating a signal to make an amplitude-modulated sine wave in-phase and quadrature, and providing an in-phase signal LO_I and its quadrature signal LO_Q of the local oscillator LO; and an off-chip oscillator (Ext. LO) for providing an oscillation signal from the outside of the chip so that clock noise may not pass through from the outside of the chip.
[0116] The interface circuit unit 73 includes: an A/D converter for receiving the in-phase signal LO_I and its quadrature signal LO_Q of the local oscillator LO received from the RF receiver circuit unit 72, and A/D converting the signals; and a temperature converter for converting a heat radiation signal into a core body temperature inside a human body corresponding to a digital value measured by the power corresponding to the RF frequency using the basic principle that radiation intensity changes almost linearly at an RF frequency lower than 10 GHz with respect to the core body temperature inside a human body by the Plank and Rayleigh Jeans approximation law, so that the heat radiation signal radiated from the inside under the skin of the human body and transferred to a surface of the skin may be converted into a body temperature value.
[0117] A/D converters of 32-bit, 64-bit, and 128-bit are used as the A/D converter.
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[0121] 1) Design of the structure and specifications of the RF receiver chip using a CMOS process for sensing core body temperature [0122] Review of required specifications of the RF receiver for sensing core body temperature, and an optimal RF/IF receiver [0123] Quantitative derivation of required specifications and design structure of a detailed circuit block utilizing an RF receiver M&S (Modeling & Simulation) method based on the required specifications and a selected RF receiver structure
[0124] 2) Design and development of an RF/IF circuit of a broadband RF receiver chip of 1 to 2 GHz [0125] Design of an RF front end circuit of the RF receiver module, including a low-noise amplifier (LNA) and down mixers for low noise, high gain, and easy gain control in a broadband of 1 to 2 GHz [0126] Design of an LO generation circuit including VCO for LO generation of 1.1 to 1.7 GHz [0127] Design of an IF stage circuit unit including circuits of an amplifier and a sensing unit including low noise, high gain, and gain control functions at the center frequency of 250 MHz [0128] Integration of the designed RF, LO, IF circuits, and optimization design of integrated performance of the entire RF receiver
[0129] 3) Layout and fabrication of an RF/IF receiver chip using a CMOS process [0130] Design and fabrication of an RF receiver module on a silicon (Si) substrate by using a CMOS process through a CMOS circuit layout process and a post layout simulation of each detailed RF, IF, and LO circuit units of an RF/IF receiver chip manufactured as a single chip using a CMOS process [0131] Layout design and overall performance review of a single receiver chip integrating the layouts of detailed circuit blocks [0132] An MIMIC chip (RF/IF receiver chip) of the RF receiver module is manufactured as one chip using the System Integration Package/Chip technology on silicon (Si) substrate using a CMOS process
[0133] 4) Manufacturing and verification of a test board of the RF receiver chip and module [0134] Design of a circuit diagram and a layout of a test board for performance evaluation of the manufactured RF receiver module [0135] Manufacture of a test board using an RF receiver module through a CMOS process, and measurement of required specifications (measuring and verifying specifications such as gain, NF, P1dB, IP3, spurious, power consumption, etc.)
[0136] RF microwave core body thermometers provided with an RF receiver module that overcomes the fundamental limit of existing infrared sensors measuring skin temperature and measures core body temperature inside a human body are localized and supplied to the digital healthcare and medical fields.
[0137] The present invention manufactures one MIMIC chip on a silicon (Si) substrate for an RF receiver module for measuring core body temperature as one chip in an RF receiver module by using a CMOS process and an RF microwave core body thermometer having the same, and provides an RF microwave core body thermometer system having an RF/IF receiver module that measures core body temperature inside a human body by using any one RF frequency signal within an RF frequency range of 1 to 10 GHz.
[0138] An infrared thermometer is limited to measurement of temperature of skin surface such as the forehead, the back of a hand, the temple or the like, whereas the RF microwave core body thermometer may measure core body temperature in most of ranges including a chest, sides, and legs, and the center portion of a torso, and may measure both the front and rear sides of a human body.
[0139] An RF microwave core body thermometers, in which an RF receiver module that overcomes the fundamental limit of existing infrared sensors measuring skin temperature and measures core body temperature inside a human body is manufactured as an MMIC chip, are localized and supplied to the digital healthcare and medical fields.
[0140] Although it has been described with reference to specific embodiments of the present invention, the present invention is not limited to the configuration and operation described in the specific embodiments to illustrate the technical spirit as described above, and it can be implemented to be diversely modified within the limit not departing from the technical spirit and scope of the present invention. Therefore, such modifications should be regarded as belonging to the scope of the present invention, and the scope of the present invention should be determined by the claims described below.