KR102381649B1 - Bio sensor using array antenna - Google Patents

Abstract

According to an embodiment, the biosensor using the array antenna is disposed to be spaced apart from each other along the periphery of the side of the object, radiates electromagnetic waves having directivity toward the inside of the object, and at least two receiving a scattered electromagnetic field. antenna elements; a signal generator for generating a feed signal according to a frequency sweep; a phase shifter that adjusts the phase of the feeding signal and transmits it to at least two antenna elements; and a controller configured to detect a position of a target part inside the object based on the received scattered electromagnetic field corresponding to the emitted electromagnetic wave by sweeping the frequency and phase of the feeding signal.

Description

Biosensor using array antenna {BIO SENSOR USING ARRAY ANTENNA}

Hereinafter, a technology related to a biosensor using an array antenna is provided.

Recently, the number of people suffering from so-called adult diseases such as diabetes, hyperlipidemia, and blood-converted persons is increasing due to the westernization of eating habits. A simple way to determine the severity of these adult diseases is to measure biocomponents in the blood. Bio-component measurement can determine the amount of various components in the blood, such as blood sugar, anemia, and blood clotting, so that the level of a specific component is in the normal or abnormal region, making it easy for the general public to determine whether there is an abnormality without going to the hospital. The advantage is that it is possible.

One of the easy methods for measuring biocomponents is to quantitatively analyze the output signal using electrochemical or photometric methods after injecting blood collected from the fingertip into a test strip. It is suitable for the general public who do not have it.

The biosensor may be used in combination with a smart device, and rapid and accurate measurement of biometric information is required.
[Prior art literature]
Korean Patent Publication No. 10-2010-0007078 (2010.01.22.)

The biosensor according to an embodiment may acquire a parameter related to a living body by emitting electromagnetic waves in an array mode and sensing the scattered electromagnetic field.

The biosensor according to an embodiment may radiate electromagnetic waves in a beam pattern with improved directivity toward blood vessels.

The biosensor according to an embodiment may acquire parameters and biometric information having different characteristics in a single mode and an array mode.

According to an embodiment, the biosensor using the array antenna is disposed to be spaced apart from each other along the periphery of the side of the object, radiates electromagnetic waves having directivity toward the inside of the object, and receives at least a scattered electromagnetic field. two antenna elements; a signal generator for generating a feed signal according to a frequency sweep; a phase shifter that adjusts the phase of the feeding signal and transmits it to the at least two antenna elements; and a controller configured to detect a position of a target part inside the object based on the scattered electromagnetic field received corresponding to the emitted electromagnetic wave by sweeping the frequency and phase of the feeding signal.

The controller may initiate measurement of biometric information for the target site in response to detecting the location of the target site.

The controller may obtain a frequency response characteristic for the scattered electromagnetic field, calculate a time delay profile from the frequency response characteristic, and determine the location of the target site based on the time delay profile.

The controller may detect a target peak from the time delay profile and determine the location of the target site based on the target peak of the time delay profile.

The controller, in response to a case in which a second peak as the target peak has a predetermined amplitude range within a predetermined delay range, generates a phase difference corresponding to the time delay profile at the at least It can hold for two antenna elements.

The controller may obtain a frequency response characteristic for each phase difference by sweeping the frequency of the feeding signal for each of the phase differences selectable by the phase shifter.

The controller may determine a direction in which the target site is located based on the biosensor.

When the at least two antenna elements operate in a single mode, one or more antenna elements radiate an electromagnetic wave and the other antenna elements receive a fringing field by the electromagnetic wave, and operate in an array mode. In response, both of the at least two antenna elements may emit an electromagnetic wave and receive the scattered electromagnetic field.

The operation time of the single mode may be longer than the operation time of the array mode.

The operation time of the single mode and the operation time of the array mode may not overlap each other.

The controller may determine blood glucose value data while operating in the single mode, and determine time delay related information of the blood glucose value data while operating in the array mode.

A beam pattern of electromagnetic waves emitted by the at least two antenna elements may be determined based on a phase difference adjusted by the phase shifter.

The at least two antenna elements receive a signal radiated from an internal sensor disposed inside the object, and the controller compares a phase between signals received by the at least two antenna elements to compare the phase between the internal sensor and the bio It is possible to determine whether the sensors are aligned.

The biosensor further includes an output unit for outputting guide information for changing a wearing position of the biosensor to the user in response to the internal sensor and the biosensor being in a misalignment state, the controller comprising: When the phases of the signals received by the at least two antenna elements are in phase, it may be determined to be in the aligned state, and if the phases of the signals received by the at least two antenna elements are different, it may be determined to be in the unaligned state.

The at least two antenna elements may be disposed along a curved surface corresponding to a curvature of the surface of the object.

According to an exemplary embodiment, a method for detecting a target site performed by a biosensor includes: generating a feeding signal for at least two antenna elements arranged to be spaced apart from each other along a periphery of a side surface of an object according to a frequency sweep; adjusting the phase of the feeding signal and transmitting it to the at least two antenna elements; the at least two antenna elements emitting an electromagnetic wave having a directivity toward the inside of the object in response to the feeding signal, and receiving a scattered electromagnetic field; and detecting a position of a target part inside the object based on the scattered electromagnetic field received corresponding to the emitted electromagnetic wave by sweeping the frequency and phase of the feeding signal.

The biosensor according to an embodiment may accurately estimate a direction in which blood vessels are located by using the scattered electromagnetic field detected in the array mode.

The biosensor according to an embodiment radiates electromagnetic waves in a beam pattern with improved directivity toward the blood vessels, thereby allowing the electromagnetic waves to penetrate to a target depth in which the blood vessels are located with minimal power.

The biosensor according to an embodiment may secure data diversity by acquiring parameters and biometric information having different characteristics in a single mode and an array mode.

The biosensor according to an embodiment may estimate a blood sugar level with a minimized time delay and improved accuracy by using the biometric information in the single mode and the biometric information in the array mode.

1 illustrates a biosensor using an array antenna according to an embodiment.
2 is a block diagram illustrating a configuration of a biosensor according to an exemplary embodiment.
3 is a diagram for explaining adjustment of a beam steering angle of a biosensor according to an exemplary embodiment.
4 illustrates a relationship between a phase difference of a feeding signal supplied to a plurality of antenna elements and a beam steering angle of an array antenna according to an exemplary embodiment.
5 is a circuit diagram of a biosensor operating in an array mode according to an exemplary embodiment.
6 illustrates an exemplary configuration of a phase shifter according to an embodiment.
7 and 8 illustrate a method for detecting a target site by a biosensor according to an exemplary embodiment.
9 and 10 illustrate a biosensor operating in a single mode, according to an exemplary embodiment.
11 and 12 illustrate a method of providing a position alignment guide between a biosensor and an internal sensor according to an exemplary embodiment.
13 and 14 illustrate a depth senseable by a biosensor and a sensing result according to an exemplary embodiment.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. However, since various changes may be made to the embodiments, the scope of the patent application is not limited or limited by these embodiments. It should be understood that all modifications, equivalents and substitutes for the embodiments are included in the scope of the rights.

The terms used in the examples are used for the purpose of description only, and should not be construed as limiting. The singular expression includes the plural expression unless the context clearly dictates otherwise. In this specification, terms such as "comprise" or "have" are intended to designate that a feature, number, step, operation, component, part, or a combination thereof described in the specification exists, but one or more other features It should be understood that this does not preclude the existence or addition of numbers, steps, operations, components, parts, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiment belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

In addition, in the description with reference to the accompanying drawings, the same components are given the same reference numerals regardless of the reference numerals, and the overlapping description thereof will be omitted. In describing the embodiment, if it is determined that a detailed description of a related known technology may unnecessarily obscure the gist of the embodiment, the detailed description thereof will be omitted.

In addition, in describing the components of the embodiment, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only for distinguishing the elements from other elements, and the essence, order, or order of the elements are not limited by the terms. When it is described that a component is "connected", "coupled" or "connected" to another component, the component may be directly connected or connected to the other component, but another component is between each component. It will be understood that may also be "connected", "coupled" or "connected".

Components included in one embodiment and components having a common function will be described using the same names in other embodiments. Unless otherwise stated, descriptions described in one embodiment may be applied to other embodiments as well, and detailed descriptions within the overlapping range will be omitted.

1 illustrates a biosensor using an array antenna according to an embodiment.

The biosensing system according to an embodiment may include a biosensor 100 and an internal sensor 150 .

The biosensor 100 using the array antenna may be a sensor that senses the target analyte 109 using electromagnetic waves. The target analyte 109 is a material associated with a living body, and may also be referred to as an analyte. For reference, in the present specification, the target analyte 109 is mainly described as blood sugar, but is not limited thereto.

The biosensor 100 may operate in one of an array mode and a single mode. The array antenna of the biosensor 100 may include at least two or more antenna elements. While the biosensor 100 operates in the array mode, each antenna element constituting the array antenna may radiate electromagnetic waves in a radiation pattern according to an array factor at the same timing. In this case, the antenna element may receive reflected or scattered electromagnetic waves. For example, the first antenna element 111 and the second antenna element 112 radiate electromagnetic waves toward the subcutaneous layer 120 of the object, and generate an electromagnetic field scattered by the target analyte 109 and the like. can receive In this specification, the array mode operation of the biosensor 100 will be mainly described, and the single mode operation of the biosensor 100 will be exemplarily described with reference to FIG. 9 below. For reference, in order to maximize the distance resolution of the array antenna, an antenna element capable of operating in a wide band may be used.

According to an embodiment, the biosensor 100 may detect the position of the target site by emitting electromagnetic waves through the array antenna while operating in the array mode, and receiving the scattered electromagnetic field in which the emitted electromagnetic waves are reflected. . The detection of the target site will be described with reference to FIG. 7 below. Also, the biosensor 100 may emit electromagnetic waves toward the target site while operating in the array mode, and determine parameters associated with the target analyte 109 based on the scattered electromagnetic field for the target site.

In the present specification, the parameter may represent a circuit network parameter used to interpret a biosensor and/or a biosensing system, and scattering parameters are mainly described below for convenience of description, but limiting this not. As parameters, for example, an admittance parameter, an impedance parameter, a hybrid parameter, a transmission parameter, and the like may be used. For the scattering parameter, a transmission coefficient and a reflection coefficient may be used. For reference, the resonant frequency of the array antenna calculated from the above parameters may be related to the concentration of the target analyte 109, and the biosensor may predict blood sugar by detecting changes in the transmission coefficient and/or reflection coefficient. .

The resonant frequency of the array antenna may vary depending on the concentration of the target analyte 109 present in the vicinity of the array antenna, as will be described later. For example, the resonance frequency may be expressed as a capacitance component and an inductance component as shown in Equation 1 below.

[Equation 1]

에 비례할 수 있다.In Equation 1 above, f may represent a resonance frequency of the array antenna, L may represent an inductance of the array antenna, and C may represent a capacitance of the array antenna. The capacitance C of the array antenna is a relative dielectric constant as shown in Equation 2 below.

can be proportional to

[Equation 2]

은 주변의 대상 피분석물(109)의 농도에 의해 영향을 받을 수 있다. 예를 들어, 배열 모드로 동작하는 어레이 안테나는 대상 부위, 예를 들어, 혈관(190)을 향해 전자기파를 방사할 수 있다. 이 때, 혈관(190)을 향해 방사된 전자기파는 주변에 존재하는 대상 피분석물(109)로 인해 산란될 수 있다. 산란되는 전자기장(scattered field)의 세기는 대상 피분석물(109)의 농도에 따라 달라질 수 있는데, 주로 대상 부위인 혈관(190) 내 포함된 대상 피분석물(109)의 농도에 따라 달라질 수 있다. 대상 피분석물(109)의 농도 변화에 따라 어레이 안테나의 상대 유전율

이 변하므로, 어레이 안테나의 공진 주파수도 함께 변화한다.Relative permittivity of array antenna

may be affected by the concentration of the target analyte 109 in the vicinity. For example, an array antenna operating in an array mode may radiate electromagnetic waves toward a target site, for example, a blood vessel 190 . At this time, the electromagnetic wave radiated toward the blood vessel 190 may be scattered due to the target analyte 109 existing in the vicinity. The intensity of the scattered electromagnetic field may vary depending on the concentration of the target analyte 109 , and may mainly vary depending on the concentration of the target analyte 109 included in the blood vessel 190 , which is the target site. . Relative permittivity of the array antenna according to the change in the concentration of the target analyte 109

As this value changes, the resonant frequency of the array antenna also changes.

이 증가할수록 어레이 안테나의 공진 주파수가 감소할 수 있다. 참고로, 도 1에 도시된 주파수 범위는 2.4GHz를 포함하는 것으로 도시되었으나, 이로 한정하는 것은 아니고, 설계에 따라 변경될 수 있다.Exemplarily, FIG. 1 shows a frequency response characteristic 199 as a measurement result of a scattering parameter for each relative permittivity of a target site in a biosensor operating in an array mode. The intensity of the scattered electromagnetic field may, for example, correspond to a reflection coefficient S ₁₁ in the first antenna element. The biosensor may acquire the frequency response characteristic 199 by measuring the reflection coefficient S ₁₁ within the frequency range. In the reflection coefficient S ₁₁ , a frequency having the lowest reflection coefficient within the frequency range may be a resonance frequency. As shown in Figure 1, the relative permittivity

As this increases, the resonant frequency of the array antenna may decrease. For reference, the frequency range shown in FIG. 1 is illustrated as including 2.4 GHz, but is not limited thereto, and may be changed according to design.

Accordingly, the biosensor 100 according to an exemplary embodiment may directly determine the biometric information on the analyte 109 in the blood vessel 190 based on the resonance frequency of the array antenna. For example, the biosensor 100 may obtain a target analyte concentration value (eg, a blood sugar level) corresponding to each resonance frequency from a mapping table (eg, a look up table (LUT)). , it is possible to determine the concentration value indicated by the resonant frequency measured at the time of measurement. However, the determination of biometric information is not limited thereto, and may be changed according to design.

In the present specification, the biometric information is information related to the subject's biocomponent, and may include, for example, the concentration and level of the analyte, and information related to the time delay between the blood sugar change in the interstitial fluid and the blood sugar change in the blood vessels. When the analyte is blood sugar, the biometric information may include a blood sugar level.

The internal sensor 150 may be inserted and/or implanted in the subcutaneous layer below the skin 191 . The biosensor 100 may establish wireless communication with the internal sensor 150 . The internal sensor 150 implanted subcutaneously may monitor the target analyte 109 present in the blood vessel 190 and the subcutaneous layer 120 . For example, the internal sensor 150 may include a resonator assembly in which a resonant frequency is changed according to a change in the concentration of the surrounding target analyte 109 , and the target analyte 109 is monitored by monitoring the resonant frequency of the resonator assembly. ) and associated additional bio-metric data may be determined. The internal sensor 150 may acquire and collect additional biometric data corresponding to the concentration of the target analyte 109 in the body, and transmit the additional biometric data to the external biosensor 100 . The additional biometric data is data related to the concentration and/or amount of the target analyte 109 , and may be, for example, a parameter related to a relative permittivity corresponding to the concentration of the analyte as described above. However, the present invention is not limited thereto, and the biometric data may include a resonant frequency corresponding to the concentration of the analyte, a scattering parameter for calculating the resonant frequency, and a frequency response characteristic corresponding to the scattering parameter. The internal sensor 150 may transmit additional biometric data to the biosensor 100 through wireless communication. Furthermore, the biosensor 100 may wirelessly supply power from the internal sensor 150 . The internal sensor 150 may monitor biometric data using wirelessly transmitted power.

2 is a block diagram illustrating a configuration of a biosensor according to an exemplary embodiment.

The biosensor 200 according to an embodiment may include an array antenna 210 , a phase shifter 220 , a signal generator 230 , and a controller 240 . The biosensor 200 may be attachable to a surface (eg, skin) of an object.

The array antenna 210 may include at least two antenna elements, and may operate in one of an array mode and a single mode. In the array mode, each antenna element can radiate electromagnetic waves at the same time. In the single mode, at least one antenna element may radiate an electromagnetic wave, and at least one of the remaining antenna elements may receive the radiated electromagnetic wave.

According to an embodiment, at least two antenna elements may be disposed to be spaced apart from each other along the periphery of the side surface of the object. The object may be a living body and/or a part of the living body (eg, a body part). For example, the object may be an upper arm and/or a lower arm of a person, and the antenna elements may be disposed spaced apart along the perimeter of the side of the person's arm. The biosensor may also be disposed on a portion corresponding to the biceps and/or triceps in the arm. In other words, the antenna elements may be disposed to be spaced apart from each other along an axis (eg, an axis perpendicular to) that intersects the longitudinal direction of the target site (eg, blood vessel). The antenna elements may emit electromagnetic waves having a directivity toward the inside of the object and receive a scattered field.

The phase shifter 220 may adjust the phase of the feeding signal and transmit it to at least two antenna elements. The phase shifter 220 may adjust a phase difference between signals supplied to each antenna element. An exemplary configuration of the phase shifter 220 will be described with reference to FIG. 6 below.

The signal generator 230 may generate a feed signal according to a frequency sweep. The signal generator 230 may include, for example, an injection locked oscillator. The signal generator 230 may generate a feeding signal while sweeping a frequency within a predefined frequency range. For example, the carrier frequency of the feeding signal may be gradually changed. The frequency range may include frequencies greater than or equal to the first frequency and less than or equal to the second frequency, and the signal generator 230 may generate the feeding signal while sequentially increasing the frequency from the first frequency to the second frequency. However, the present invention is not limited thereto, and the signal generator 230 may generate the feeding signal while sequentially decreasing the frequency from the second frequency to the first frequency.

The controller 240 may detect the position of the target part inside the object based on the received scattered electromagnetic field corresponding to the emitted electromagnetic wave by sweeping the frequency and phase of the feeding signal.

3 is a diagram for explaining adjustment of a beam steering angle of a biosensor according to an exemplary embodiment.

The biosensor according to an embodiment may change the beam steering angle of the electromagnetic wave while emitting the electromagnetic wave into the object through the plurality of antenna elements 311 , 312 , 313 , and 314 . For example, the biosensor may change the radiation pattern by the array antenna by adjusting the intensity and phase of the signals fed to the plurality of antenna elements 311 , 312 , 313 , and 314 according to the array factor. For example, the radiation pattern of each of the plurality of antenna elements 311 , 312 , 313 , and 314 overlaps according to an array factor, so that electromagnetic wave radiation may be concentrated in a specific direction. In this array mode, the biosensor can transmit electromagnetic waves more deeply with relatively less power than in the single mode. In addition, since electromagnetic wave radiation is concentrated in a direction according to the beam steering, a biological effect can be minimized. For reference, although four antenna elements 311 , 312 , 313 , and 314 are illustrated in FIG. 3 , the present invention is not limited thereto.

Whenever the beam steering angle is changed, the biosensor may attempt to detect the target site in a direction corresponding to the beam steering angle with respect to the biosensor. The target site may be, for example, a blood vessel 390 . The relative permittivity of the target site may be, for example, 80 or more, and the relative permittivity of the subcutaneous layer 320 may be approximately 5. Since the relative permittivity of the target site is greater than the relative permittivity of the subcutaneous layer 320 , when electromagnetic waves are radiated toward the target site, scattering by strong reflected waves may occur. For example, when the electromagnetic wave is emitted with respect to the first steering angle 381 , the intensity of the scattered electromagnetic field may be small. When the electromagnetic wave is emitted with respect to the second steering angle 382 , the intensity of the scattered electromagnetic field may be large due to a sharp difference in relative permittivity between the target region 390 and the subcutaneous layer 320 . Accordingly, the biosensor may determine whether a target site exists at a position corresponding to the corresponding beam steering angle by monitoring the scattered electromagnetic field for each individual beam steering angle. The detection of the target site will be described in detail with reference to FIG. 7 below.

According to an embodiment, a surface on which the plurality of antenna elements 311 , 312 , 313 , and 314 are disposed may have a curvature. The plurality of antenna elements 311 , 312 , 313 , and 314 may be disposed along a surface (eg, a curved surface) corresponding to the curvature of the surface of the object. For example, the plurality of antenna elements 311 , 312 , 313 , and 314 may be disposed along a surface fitted to a curved surface of an outer circumference perpendicular to the length direction of the object. For example, FIG. 3 is a cross-sectional view perpendicular to the longitudinal axis of the object, in which the plurality of antenna elements 311 , 312 , 313 , and 314 are disposed in close contact with the surface of the object. The plurality of antenna elements 311 , 312 , 313 , 314 may be individually and/or integrally accommodated in the housing, and in this case, may have a curvature of a face contacting the object in the housing. Similarly, the surface of the housing in contact with the object may have the same or similar curvature to the curved surface of the outer periphery perpendicular to the longitudinal direction of the object. Also in FIG. 1, the surface on which the antenna element is disposed is shown as a curved surface. Therefore, since the antenna element and the housing accommodating the antenna element are in close contact with the surface (eg, skin) of the object, the air gap is minimized, and radiation loss can be minimized.

4 illustrates a relationship between a phase difference of a feeding signal supplied to a plurality of antenna elements and a beam steering angle of an array antenna according to an exemplary embodiment.

는 어레이 안테나(410)에 의한 스티어링 범위의 중심축(490)을 기준으로 하는 각도일 수 있다. 빔 스티어링 각도

에 대한 안테나 소자들 간의 위상 차이

는 아래 수학식 3과 같이 나타낼 수 있다.The array antenna 410 may include M antenna elements, where M may be an integer of 2 or more. Beam steering angle in the array antenna 410 of the biosensor

may be an angle based on the central axis 490 of the steering range by the array antenna 410 . Beam Steering Angle

Phase difference between antenna elements for

can be expressed as in Equation 3 below.

[Equation 3]

는 방사되는 전자기파의 파장, d는 안테나 소자들 간의 간격, k는 상술한 파장 및 간격에 의해 결정되는 상수를 나타낼 수 있다. 바이오 센서는 중심축(490)을 기준으로 빔 스티어링 각도

를 향하는 방사 패턴(480)으로 전자기파를 방사하기 위해, 개별 안테나 소자들 간 위상 차이

로 각 안테나 소자에 피딩 신호를 공급할 수 있다. 예를 들어, 제1 안테나 소자(421)에 공급되는 피딩 신호를 기준으로, 위상 시프터(420)는 제2 안테나 소자에 대해

, 제3 안테나 소자에 대해 2

, 제M 안테나 소자에 대해 (M-1)

만큼 각각 신호를 지연시켜 공급할 수 있다. 하기 도 7에서 후술하겠으나, 각도 해상도(angle resolution)에 따라 정의된 빔 스티어링 각도들마다 복수의 위상 차이들이 결정될 수 있고, 바이오 센서는 복수의 위상 차이들을 순차적으로 선택하여 선택된 위상 차이에 따른 피딩 신호를 안테나 소자들에 공급할 수 있다.In Equation 3 above,

may represent a constant determined by the wavelength of the radiated electromagnetic wave, d is an interval between antenna elements, and k is the above-described wavelength and interval. The biosensor has a beam steering angle with respect to the central axis 490 .

To radiate electromagnetic waves with a radiation pattern 480 toward

to supply a feeding signal to each antenna element. For example, based on the feeding signal supplied to the first antenna element 421 , the phase shifter 420 may be configured with respect to the second antenna element.

, 2 for the third antenna element

, for the Mth antenna element (M-1)

Each signal can be delayed and supplied. As will be described later with reference to FIG. 7 , a plurality of phase differences may be determined for each beam steering angle defined according to angle resolution, and the biosensor sequentially selects a plurality of phase differences to obtain a feeding signal according to the selected phase difference. can be supplied to the antenna elements.

5 is a circuit diagram of a biosensor operating in an array mode according to an exemplary embodiment.

The biosensor 500 may include an array antenna 510 , a phase shifter 520 , a signal integrator 540 , and a signal generator 530 . The array antenna 510 may include, for example, a first antenna element and a second antenna element. As described above, the signal generator 530 may generate a feeding signal. The phase shifter 520 may delay the feeding signal by a phase corresponding to w ₁ with respect to the first antenna element and a phase corresponding to w ₂ with respect to the second antenna element to be provided to each antenna element. Each phase has a relationship as in Equation 4 below.

[Equation 4]

를 향해 전자기파를 방사할 수 있다. 이 때, 대상 부위(590)가 해당 방향에 존재하는 경우, 강한 산란되는 전기장 E_SF이 발생할 수 있다. 제1 안테나 소자 및 제2 안테나 소자에 대응하는 파라미터는 예시적으로 각각 하기 수학식 5 및 수학식 6와 같이 나타낼 수 있다.By the above-described phase feeding, the first antenna element and the second antenna element have a beam steering angle.

It can radiate electromagnetic waves toward In this case, when the target region 590 is present in the corresponding direction, a strong scattered electric field E _SF may be generated. Parameters corresponding to the first antenna element and the second antenna element may be exemplarily expressed as Equations 5 and 6, respectively.

[Equation 5]

[Equation 6]

은 제1 안테나 소자의 총 반사 계수로서, 제1 안테나 소자 자체 반사 계수

및 산란되는 전기장 E_SF의 합일 수 있다. 유사하게, 상술한 수학식 6에서

은 제2 안테나 소자의 총 반사 계수로서, 제2 안테나 소자 자체 반사 계수

및 산란되는 전기장 E_SF의 합일 수 있다. 바이오 센서(500)는 위상 시프터(520)에 의한 위상 지연으로 인해, 하기 수학식 7과 같은 반사 계수를 획득할 수 있다.In Equation 5 above,

is the total reflection coefficient of the first antenna element, and is the reflection coefficient of the first antenna element itself.

and the scattered electric field E _SF . Similarly, in Equation 6 above,

is the total reflection coefficient of the second antenna element, and the second antenna element self-reflection coefficient

and the scattered electric field E _SF . The biosensor 500 may obtain a reflection coefficient as shown in Equation 7 below due to the phase delay by the phase shifter 520 .

[Equation 7]

마다, 피딩 신호의 주파수를 스윕하면서 상술한 수학식 7에 따른 파라미터를 측정함으로써 산란된 전자기장에 대한 주파수 응답 특성을 획득할 수 있다.The biosensor 500 may acquire a signal integrated by the signal integrator 540 through the phase shifter 520 of the signal individually received through each antenna element of the array antenna 510 . In Equation 7 described above, y may represent a parameter (eg, a reflection coefficient) of a signal received through the array antenna 510 and integrated. The biosensor 500 may measure an integrated parameter with respect to a plurality of antenna elements included in the array antenna, instead of measuring a parameter for each individual antenna element. The biosensor 500 has each beam steering angle

The frequency response characteristic to the scattered electromagnetic field may be obtained by measuring the parameter according to Equation 7 above while sweeping the frequency of the feeding signal.

6 illustrates an exemplary configuration of a phase shifter according to an embodiment.

The phase shifter 620 may provide a phase difference between the first antenna element 611 and the second antenna element 612 by delaying the feeding signal generated by the signal generator 630 . For example, the phase shifter 620 may include a plurality of signal paths 621 , 622 , and 623 selectable by a phase control signal of a controller. The phase of the feeding signal supplied to the corresponding antenna element may vary according to the length of the signal path selected between the respective antenna elements from the signal generator 630 . Accordingly, the controller may adjust the phase delay for the corresponding antenna element by selecting the signal path of the phase shifter 620 for each antenna element through the phase control signal.

For reference, while the biosensor operates in the array mode, the path selector 640 may form a path from the signal generator 630 to each antenna element in the array mode as shown in FIG. 6 . Accordingly, in the arrangement mode, the path selector 640 may operate as the signal integrator described above with reference to FIG. 5 . While the biosensor operates in a single mode, the path selector 640 connects a transmit antenna (eg, a first antenna element) and a signal generator 630 and a receive antenna (eg, a second antenna element) ) and the signal generator 630 may be separated. However, the configuration of the path selector 640 is not limited thereto, and may be changed according to design.

7 and 8 illustrate a method for detecting a target site by a biosensor according to an exemplary embodiment.

First, in step 710 , the biosensor may scan the frequency response characteristic 810 for each phase. According to an embodiment, the controller may acquire the frequency response characteristic 810 for each phase difference by sweeping the frequency of the feeding signal for each of the phase differences selectable by the phase shifter.

에 따라 선택 가능한 빔 스티어링 각도들(예를 들어, 제1 각도

, 제2 각도

, 내지 제K 각도

, 여기서, K는 2이상의 정수)이 미리 정의될 수 있다. 위상 시프터는 미리 정의된 복수의 빔 스티어링 각도들에 대한 위상 차이를 제공할 수 있다. 제어기는 위상 시프터에 의해 선택 가능한 복수의 위상 차이들 중 한 위상 차이를 선택할 수 있다. 위상 시프터가 선택된 위상 차이로 어레이 안테나에 피딩함으로써, 제어기는 대응하는 빔 스티어링 각도로 방사된 전자기파에 대해 산란된 전자기장에 관한 파라미터를 측정할 수 있다. 제어기는 해당 빔 스티어링 각도에 대해 주파수를 스윕하면서 파라미터를 측정함으로써, 해당 빔 스티어링 각도의 산란된 전자기장에 대한 주파수 응답 특성(810)을 획득할 수 있다.For example, angle resolving power within the steerable range by the array antenna.

Selectable beam steering angles according to (eg, the first angle

, second angle

, to Kth angle

, where K is an integer of 2 or more) may be predefined. The phase shifter may provide a phase difference for a plurality of predefined beam steering angles. The controller may select one of a plurality of phase differences selectable by the phase shifter. By feeding the phase shifter to the array antenna with a selected phase difference, the controller can measure a parameter regarding the scattered electromagnetic field for the electromagnetic wave radiated at the corresponding beam steering angle. The controller may acquire the frequency response characteristic 810 for the scattered electromagnetic field of the corresponding beam steering angle by measuring the parameter while sweeping the frequency for the corresponding beam steering angle.

And in step 720 , the biosensor may calculate a time delay profile 820 . For example, the controller can calculate the time delay profile 820 from the frequency response characteristic 810 . The controller may calculate the time delay profile 820 by transforming the frequency response characteristic 810 into the time domain (eg, inverse transform of a fast Fourier transform (FFT)). The frequency response characteristic 810 may be a reflection coefficient S ₁₁ among scattering parameters as shown in FIG. 8 .

Subsequently, in step 730 , the biosensor may detect the target peak. The controller may determine the location of the target site based on the time delay profile 820 . For example, the controller may detect a target peak from the time delay profile 820 and determine the location of the target site based on the target peak in the time delay profile 820 . The controller may detect the second peak 892 as the target peak. The second peak 892 may indicate a peak having the second largest intensity in descending order among peaks detected in the time delay profile 820 . The first peak 891 (eg, the peak of greatest intensity) may be caused by self-reflection of the antenna element. The second peak 892 is generated by the scattered electromagnetic field, and a delay occurs from the antenna element to the target site (eg, blood vessel) after the electromagnetic wave is reflected and received, so it is later than the first peak 891 . may appear in

Exemplarily, in step 731 , the controller may determine whether a target peak equal to or greater than a threshold value 821 is detected. For example, the controller may search for a point where the threshold value 821 is exceeded, except for the first peak 891 in the time delay profile 820 . If only values below the threshold value 821 are detected except for the first peak 891 , the controller may adjust the threshold value 821 at step 732 . For example, the controller may decrease the threshold and perform the operation according to step 731 . Accordingly, the controller may gradually decrease the threshold until a second peak 892 is detected.

In operation 740, the biosensor may determine the location of the target site based on the target peak. The controller is responsive to the case where the second peak 892 as the subject peak has a predetermined amplitude range within a predetermined delay range 822, the time delay profile in which the subject peak is detected. It may be determined that the target site is present at the beam steering angle corresponding to 820 . Considering the depth from the skin to the blood vessel, the second peak 892 for the blood vessel may occur within the delay time range and within the size range. Accordingly, the controller may exclude peaks outside the delay time range 822 or magnitude range from determining the target site. The controller may determine a direction in which the target site is located based on the biosensor.

The controller according to an embodiment may maintain a phase difference corresponding to the time delay profile 820 in which the target part is detected with respect to at least two antenna elements in response when the direction in which the target part is located is determined. As described above, the beam pattern of the electromagnetic wave radiated by at least two antenna elements may be determined based on the phase difference adjusted by the phase shifter. Accordingly, the biosensor can form and maintain the beam pattern of the array antenna in a direction facing the target site.

The controller may initiate measurement of biometric information for the target site in response to detecting the location of the target site. For example, the controller may measure an intravascular blood glucose level and/or time delay related information of a blood glucose change between an interstitial fluid and a blood vessel as biometric information. Measurement of blood glucose level in blood vessels is described above with reference to FIG. 1 , and information related to time delay will be described with reference to FIG. 14 below.

For reference, in FIG. 7, the controller acquires the frequency response characteristic 810 for one steering angle and performs the rest of the operation, and when the position of the target part is not detected, the beam steering angle is changed and restarted from step 710 Examples have been described. However, the present invention is not limited thereto, and the controller may acquire the frequency response characteristics 810 for all beam steering angles while sequentially changing the beam steering angle and perform the remaining operations (eg, 720 to 740 ). .

9 and 10 illustrate a biosensor operating in a single mode, according to an exemplary embodiment.

At least two antenna elements 911 and 912 of the biosensor 900 may operate in an array mode or a single mode. As described above, both of the at least two antenna elements 911 and 912 may emit electromagnetic waves and receive the scattered electromagnetic field in response to the case that the at least two antenna elements 911 and 912 operate in the array mode. 9 and 10 describe a single mode operation.

At least two antenna elements 911 and 912 may be operated in a single mode, in response to one or more antenna elements radiating electromagnetic waves and the other antenna elements receiving a fringing field by the electromagnetic waves. . For example, the first antenna element 911 may emit electromagnetic waves, and the second antenna element 912 may receive the peripheral field 950 . The biosensor 900 may measure the transmission coefficient 990 S ₂₁ as a scattering parameter based on the intensity received from the second antenna element 912 compared to the intensity of the signal emitted from the first antenna element 911 . . The transmission coefficient 990 S ₂₁ of the biosensor 900 may represent the highest value with respect to the resonant frequency within a specific frequency range. Similar to the array mode, the resonant frequency of the biosensor 900 operating in the single mode may change according to the relative permittivity corresponding to the concentration of the target analyte 909 . For reference, the range for searching the resonance frequency is illustrated as a range including 13.56 MHz in FIG. 9, but is not limited thereto, and may be changed according to design.

In the array antenna 1010 operating in a single mode, electrical paths of the first antenna element 911 and the second antenna element 912 may be separated as shown in FIG. 10 . The first antenna element 911 may radiate electromagnetic waves in response to the feeding signal generated by the signal generator 1030 . The second antenna element 912 may receive the peripheral field 950 .

According to an embodiment, the operation time of the single mode may be longer than the operation time of the array mode. The operation time of the single mode and the operation time of the array mode may not overlap each other. The biosensor 900 may acquire first biometric information during the single mode and acquire second biometric information during the array mode. The first biometric information and the second biometric information may include data related to the same target analyte and exhibiting different characteristics. For example, the first biometric information may include data regarding the concentration level of the target analyte (eg, blood sugar) present in the interstitial fluid of the subcutaneous layer. The second biometric information may include data regarding the concentration level of the target analyte existing in the blood vessel. Since the time for the change in the concentration in blood vessels to affect the subcutaneous layer is somewhat delayed, the second bio-information may exhibit a characteristic sensitive to the change in concentration compared to the first bio-information. The first biometric information may indicate a higher blood glucose measurement accuracy than the second biometric information. Accordingly, the biosensor 900 may fuse the first biometric information and the second biometric information to determine a precise and accurate biometric measurement result. The fusion of the first biometric information and the second biometric information may be performed by an operation according to a Bayesian filter-based algorithm, but is not limited thereto. The characteristics of the first biometric information and the second biometric information will be described with reference to FIG. 14 below.

11 and 12 illustrate a method of providing a position alignment guide between a biosensor and an internal sensor according to an exemplary embodiment.

First, in step 1110 , the biosensor 1210 may receive a signal radiated from the internal sensor 1230 through each antenna element of the array antenna. The internal sensor 1230 may be disposed inside the object and may radiate an electromagnetic wave signal for position alignment.

And in step 1120, the biosensor 1210 may compare the phases of the received signals. For example, the controller may determine whether the internal sensor 1230 and the biosensor 1210 are aligned by comparing phases between signals received by at least two antenna elements.

Subsequently, in step 1130, the controller may determine whether the phases of the received signals are in-phase. For example, in FIG. 12 , it is assumed that the array antenna of the biosensor 1210 includes the first antenna element 1211 and the second antenna element 1212 , and the internal sensor 1230 includes the third antenna element. can do. The first antenna element 1211 and the second antenna element 1212 may each receive the electromagnetic wave signal for position alignment radiated by the third antenna element. In the alignment state, since the distance from the internal sensor 1230 to the first antenna element 1211 and the distance from the internal sensor 1230 to the second antenna element 1212 are the same, the phases may be the same. In the unaligned state, since the distance from the internal sensor 1230 to each antenna element of the biosensor 1210 is different, the phase of the received signal may be different. For example, as shown in the phase graph 1290 , since the phase of the aligned state and the phase of the non-aligned state are different, deterioration in measurement accuracy may occur. The biosensor 1210 has a phase of the transmission coefficient S ₁₃ with respect to the signal radiated from the third antenna element and received from the first antenna element 1211 and received from the second antenna element 1212 radiated from the third antenna element. By comparing the phases of the transmission coefficients S ₂₃ with respect to the signal, it can be determined whether they are the same. The controller may determine that there is an alignment state when the phases of the signals received by the at least two antenna elements are in-phase, and end the position alignment process.

In step 1140 , when the phases of signals received by at least two antenna elements are different from each other, the controller may determine that the signal is in an unaligned state. The biosensor 1210 according to an embodiment may further include an output unit for outputting information related to position alignment. For example, the output unit may output guide information for changing the wearing position of the biosensor 1210 to the user in response to a case in which the internal sensor 1230 and the biosensor 1210 are in a misalignment state. . The guide information may include information regarding a change direction of a position on an object surface required for the biosensor 1210 to be aligned. Accordingly, the biosensor 1210 provides guide information for position alignment with respect to the internal sensor 1230 , thereby minimizing performance degradation due to misalignment.

13 and 14 illustrate a depth senseable by a biosensor and a sensing result according to an exemplary embodiment.

13 illustrates the electromagnetic wave penetration depth of the biosensor 1310 operating in the single mode and the biosensor 1320 operating in the array mode. The array antenna of the biosensor 1320 operating in the array mode may exhibit a greater penetration depth compared to the single mode by emitting electromagnetic waves of a focused beam pattern at a beam steering angle toward a target site (eg, a blood vessel in the body). The electromagnetic wave of the array mode may have improved directivity compared to the electromagnetic wave of the single mode. In the biosensor 1320 in the array mode, since the electromagnetic wave penetration depth is improved with minimal power, the electromagnetic wave loss due to the high dielectric constant of the skin layer is minimized, and further, the electromagnetic wave compatibility test in the body can be satisfied.

Compared to the biosensor 1310 operating in a single mode in multi-layer modeling of a cross-section of an arm, the biosensor 1320 in an array mode may provide electromagnetic wave transmission to blood vessels. Since the distance between the reachable point and the blood vessel of the electromagnetic wave emitted by the biosensor 1320 in the array mode is shorter than the distance between the reachable point and the blood vessel in the single mode, the biosensor 1320 in the array mode detects a sudden change in blood sugar. can detect For example, referring to FIG. 13 , the blood sugar change trend 1420 based on the biometric information sensed by the biosensor 1320 in the array mode is a blood sugar change trend 1490 rather than the blood sugar change trend 1410 in the single mode. ) can be sensitively followed.

Therefore, the biosensor minimizes the time delay in blood glucose measurement by determining interstitial fluid-based biometric information in single mode, determining blood vessel-based biometric information in array mode, and complexly fusing biometric information with different characteristics. , the blood glucose measurement accuracy can also be maintained. Exemplarily, the controller of the biosensor may determine the blood sugar value data as the first biometric information while operating in the single mode, and determine the time delay related information of the aforementioned blood sugar value data as the second biometric information while operating in the array mode. can The controller may calculate a difference (eg, time delay related information) between a change start time of the interstitial fluid-based blood glucose level estimated in the single mode and a change start time of the blood vessel-based blood glucose level estimated in the array mode. Thereafter, when a change in the blood vessel-based blood sugar level estimated in the array mode is detected at an arbitrary point in time, the controller calculates the blood sugar level at that point in time by using previously recorded interstitial fluid-based blood sugar level change and time delay related information. It can be estimated accurately and quickly.

The biosensor according to an embodiment may secure continuity of accuracy by blocking a change in performance due to an external environment. In addition, the biosensor can secure data diversity by collecting biometric information of interstitial fluid-based characteristics and blood vessel-based characteristics, and furthermore, by collecting information from internal sensors. Illustratively, the biosensor is a Bayesian (Byesian (eg, temperature, humidity, pressure, inertia, etc.) measurement data associated with biometric information acquired in multi-mode (eg, single mode and array mode), and external environment (eg, temperature, humidity, pressure, inertia, etc.) By applying a Bayesian filter-based algorithm, accurate blood sugar levels can be monitored in real time.

As described above, although the embodiments have been described with reference to the limited drawings, those skilled in the art may apply various technical modifications and variations based on the above. For example, the described techniques are performed in an order different from the described method, and/or the described components of the system, structure, apparatus, circuit, etc. are combined or combined in a different form than the described method, or other components Or substituted or substituted by equivalents may achieve an appropriate result.

Therefore, other implementations, other embodiments, and equivalents to the claims are also within the scope of the following claims.

Claims (16)

In the biosensor using an array antenna,
at least two antenna elements arranged to be spaced apart from each other along the periphery of the side of the object, radiating an electromagnetic wave having a directivity toward the inside of the object, and receiving a scattered field;
a signal generator for generating a feed signal according to a frequency sweep;
a phase shifter that adjusts the phase of the feeding signal and transmits it to the at least two antenna elements; and
A controller that detects a position of a target part inside the object based on the scattered electromagnetic field received corresponding to the emitted electromagnetic wave by sweeping the frequency and phase of the feeding signal
including,
The at least two antenna elements,
Receiving a signal radiated from an internal sensor disposed inside the object,
The controller is
A biosensor that compares phases between signals received by the at least two antenna elements to determine whether alignment between the internal sensor and the biosensor is performed. According to claim 1,
The controller is
In response to detecting the position of the target site, starting measurement of biometric information for the target site,
biosensor. According to claim 1,
The controller is
obtaining a frequency response characteristic for the scattered electromagnetic field, calculating a time delay profile from the frequency response characteristic, and determining a position of the target site based on the time delay profile;
biosensor. 4. The method of claim 3,
The controller is
detecting a target peak from the time delay profile and determining the location of the target site based on the target peak in the time delay profile;
biosensor. 5. The method of claim 4,
The controller is
In response to a case in which a second peak as the target peak has a predetermined amplitude range within a predetermined delay range, a phase difference corresponding to the time delay profile is measured by the at least two antenna elements. to keep about,
biosensor. 4. The method of claim 3,
The controller is
By sweeping the frequency of the feeding signal for each of the phase differences selectable by the phase shifter, a frequency response characteristic for each phase difference is obtained,
biosensor. According to claim 1,
The controller is
determining the direction in which the target site is located based on the biosensor,
biosensor. According to claim 1,
The at least two antenna elements,
In response to operating in a single mode, one or more antenna elements radiate an electromagnetic wave and the remaining antenna elements receive a fringing field by the electromagnetic wave,
in response to operating in an array mode, both the at least two antenna elements radiate electromagnetic waves and receive the scattered electromagnetic fields;
biosensor. 9. The method of claim 8,
The operation time of the single mode is longer than the operation time of the array mode,
biosensor. 9. The method of claim 8,
The operation time of the single mode and the operation time of the array mode do not overlap each other,
biosensor. 9. The method of claim 8,
The controller is
determining blood glucose value data while operating in the single mode, and determining time delay related information of the blood glucose value data while operating in the array mode;
biosensor. According to claim 1,
The beam pattern of the electromagnetic wave radiated by the at least two antenna elements is determined based on the phase difference adjusted by the phase shifter,
biosensor. delete According to claim 1,
An output unit for outputting guide information for changing a wearing position of the biosensor to a user in response to a case in which the internal sensor and the biosensor are in a misalignment state
further comprising,
The controller is
If the phases of the signals received by the at least two antenna elements are in phase, it is determined that the alignment state is
When the phases of the signals received by the at least two antenna elements are different, it is determined that the non-aligned state is
biosensor. According to claim 1,
wherein the at least two antenna elements are disposed along a curved surface corresponding to a curvature at the surface of the object,
biosensor. In the method for detecting a target site performed by a biosensor,
generating a feeding signal for at least two antenna elements spaced apart from each other along a periphery of a side surface of the object according to a frequency sweep;
adjusting the phase of the feeding signal and transmitting it to the at least two antenna elements;
the at least two antenna elements emitting an electromagnetic wave having a directivity toward the inside of the object in response to the feeding signal, and receiving a scattered electromagnetic field; and
detecting the position of the target part inside the object based on the scattered electromagnetic field received in response to the emitted electromagnetic wave by sweeping the frequency and phase of the feeding signal;
including,
The at least two antenna elements,
Receiving a signal radiated from an internal sensor disposed inside the object,
The step of detecting the position comprises:
Comparing phases between signals received by the at least two antenna elements to determine whether alignment between the internal sensor and the biosensor is performed.

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