KR20230070927A - Array-type detector unit structure, millimeter wave communication device and imaging system having the same - Google Patents

Abstract

An array type detector unit structure and a millimeter wave communication device and imaging system including the same are disclosed. A millimeter wave communication device according to an embodiment disclosed herein is a millimeter wave communication device including an arrayed detector unit structure for detecting a millimeter wave signal, wherein the unit structure includes four antenna cells arranged in a 2×2 form, Some of the four antenna cells have a first linear polarization, and others have a second linear polarization perpendicular to the first linear polarization.

Description

ARRAY-TYPE DETECTOR UNIT STRUCTURE, MILLIMETER WAVE COMMUNICATION DEVICE AND IMAGING SYSTEM HAVING THE SAME}

Embodiments of the present invention relate to techniques for detecting millimeter wave signals.

Millimeter wave has clear frequency characteristics for non-polar and polar substances, has a shorter wavelength than conventional electromagnetic waves, and has high resolution. Compared to X-rays, it is harmless to the human body because it does not ionize molecules. . Due to these millimeter wave characteristics, millimeter waves are used in various imaging systems such as foreign material detection in food, non-destructive inspection, security inspection, and semiconductor inspection.

One of the performance indicators of a millimeter wave imaging system is an image signal-to-noise ratio. An image signal-to-noise ratio is expressed as a value obtained by dividing a maximum output voltage by a minimum output voltage when output values of a detector for an object to be acquired are 1 frame.

On the other hand, in order to acquire millimeter wave images in real time, a single detector is being designed by extending it to an array detector. This increases the image acquisition speed, but since the signals from adjacent antennas are seen as noise, the noise between adjacent antennas is reduced to improve image quality. Skills are needed to improve performance.

In general, in order to improve the separation characteristics between antennas, arrangement design is performed with a sufficient distance between antennas, but in this case, there is a limitation in occupying a large area to implement an array type detector. In addition, in order to reduce the leakage signal between adjacent antennas, a layout design was performed to add a separate spacing structure between antennas, but the size of the physical space considering frequency selectivity generated by using the spacing structure acts as a limiting factor.

Korean Patent Publication No. 10-2003-0012924 (2003.02.12)

An embodiment of the present invention is to provide an array type detector unit structure capable of improving a signal-to-noise ratio without a separation distance between antennas, and a millimeter wave communication device and imaging system including the same.

An embodiment of the present invention is to provide an array type detector unit structure capable of easily extending the array of antenna cells of the unit structure, and a millimeter wave communication device and imaging system including the same.

A millimeter wave communication device according to an embodiment disclosed herein is a millimeter wave communication device including an arrayed detector unit structure for detecting a millimeter wave signal, wherein the unit structure includes four antenna cells arranged in a 2×2 form , Some of the four antenna cells have a first linear polarization, and others have a second linear polarization perpendicular to the first linear polarization.

In the unit structure, the direction of polarization between antenna cells adjacent to each other in the left-right direction and the vertical direction may be provided to be vertical.

In the unit structure, polarization directions between antenna cells arranged in a diagonal direction may be provided in the same manner.

The four antenna cells may be formed by contacting each other between antenna cells disposed in a first direction and antenna cells disposed in a second direction perpendicular to the first direction.

The millimeter wave communication device further includes input and output pads formed on a first side edge of the unit structure and a second side edge perpendicularly adjacent to the first side edge, and the four unit structures rotate in a clockwise direction. As it is arranged, it can be expanded into a 4x4 form.

The millimeter wave communication device may further include a signal analyzer that analyzes the magnitude and phase of the millimeter wave signal detected by the unit structure.

The signal analyzer calculates the magnitude of the millimeter wave signal in the first direction by summing the magnitudes of the millimeter wave signals received from the antenna cells having the first linear polarization among the four antenna cells, and calculating the magnitude of the millimeter wave signal in the first direction. The magnitude of the millimeter wave signal in a second direction perpendicular to the first direction is calculated by summing the magnitudes of the millimeter wave signals received from the antenna cells having the second linear polarization, and the magnitude of the millimeter wave signal in the first direction and the The magnitude of the detected millimeter wave signal may be calculated based on the magnitude of the millimeter wave signal in the second direction.

The signal analyzer may calculate the magnitude (α) of the detected millimeter wave signal by the following equation.

(mathematical expression)

V _x : Magnitude of millimeter wave signal in the first direction

V _y : Magnitude of millimeter wave signal in second direction

The signal analyzer may calculate the phase of the detected millimeter wave signal based on the magnitude of the millimeter wave signal in the first direction and the magnitude of the millimeter wave signal in the second direction.

The signal analyzer may calculate the phase φ of the detected millimeter wave signal by the following equation.

(Equation 2)

V _x : Magnitude of millimeter wave signal in the first direction

V _y : Magnitude of millimeter wave signal in second direction

In the unit structure, the array of antenna cells may be extended in the form of n×m (n and m are natural numbers of 3 or more, respectively).

In the unit structure, the direction of polarization between antenna cells adjacent to each other in the left and right directions and the vertical direction may be provided to be vertical, and the direction of polarization between antenna cells arranged in a diagonal direction may be provided to be the same.

An arrayed detector unit structure according to an embodiment disclosed herein is a unit structure for detecting a millimeter wave signal, and four antenna cells are arranged in a 2×2 shape, and some of the four antenna cells have a first linear polarization , and the remainder has a second linear polarization perpendicular to the first linear polarization.

Among the antenna cells, polarization directions between antenna cells adjacent to each other in the left-right and up-down directions may be vertical.

Among the antenna cells, the direction of polarization between antenna cells arranged in a diagonal direction may be provided in the same manner.

In the unit structure, the array of antenna cells may be extended in the form of n×m (n and m are natural numbers of 3 or more, respectively).

According to the disclosed embodiment, by making the polarization directions of mutually adjacent antenna cells different from each other by 90° in a 2×2 unit structure, it is possible to reduce signals coupled between adjacent antenna cells, and in the unit structure Since both dual polarizations (eg, horizontal polarization and vertical polarization) are received, it is possible to maintain the magnitude of the received millimeter wave signal, thereby increasing the signal to noise ratio (SNR).

In addition, since the polarization directions of adjacent antenna cells are perpendicular to each other, it is possible to design by narrowing the distance between antenna cells, thereby overcoming physical limitations for increasing the separation characteristics between antenna cells.

In addition, since the unit structure is composed of antenna cells having horizontal polarization and vertical polarization, the millimeter wave signal can be detected regardless of the polarization direction of the millimeter wave signal. In addition, since the magnitude (Vx) of the millimeter wave signal in the horizontal direction and the magnitude (Vy) of the millimeter wave signal in the vertical direction can be detected respectively, even if a polarization shift occurs in the millimeter wave signal, the original magnitude and polarization of the millimeter wave signal The shifted angle (i.e., how much the polarization is distorted) can also be obtained. As a result, it is possible to recognize polarized waves shifted by an object, detect various polarized waves including circular polarized waves, and use them for direction analysis and detection of an object.

In addition, since the unit structure can easily be expanded to an n×m shape through repeated arrangement, large-area pixels can be implemented by configuring an array type detector to suit an imaging system to which a millimeter wave communication device is applied.

1 is a schematic diagram of a millimeter wave communication device according to an embodiment of the present invention;
2 schematically shows the structure of an array type detector unit according to an embodiment of the present invention.
3 is a diagram for explaining polarization transition of a millimeter wave signal in an embodiment of the present invention.
4 is a diagram showing a state in which a signal analyzer analyzes the magnitude and phase of a millimeter wave signal in one embodiment of the present invention;
5 is a graph comparing signal-to-noise ratio (SNR) between adjacent antenna cells in a unit structure according to an embodiment of the present invention when the polarization direction is the same and when the polarization direction is vertical
6 is a diagram comparing the size of a unit structure between adjacent antenna cells in the same polarization direction and in a case where the polarization direction is vertical in the unit structure according to an embodiment of the present invention.
7 is a view showing a state in which a unit structure is expanded according to an embodiment of the present invention;
8 is a view showing another embodiment in which a unit structure according to an embodiment of the present invention is extended;

Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. The detailed descriptions that follow are provided to provide a comprehensive understanding of the methods, devices and/or systems described herein. However, this is only an example and the present invention is not limited thereto.

In describing the embodiments of the present invention, if it is determined that the detailed description of the known technology related to the present invention may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted. In addition, terms to be described later are terms defined in consideration of functions in the present invention, which may vary according to the intention or custom of a user or operator. Therefore, the definition should be made based on the contents throughout this specification. Terminology used in the detailed description is only for describing the embodiments of the present invention and should in no way be limiting. Unless expressly used otherwise, singular forms of expression include plural forms. In this description, expressions such as "comprising" or "comprising" are intended to indicate any characteristic, number, step, operation, element, portion or combination thereof, one or more other than those described. It should not be construed to exclude the existence or possibility of any other feature, number, step, operation, element, part or combination thereof.

Meanwhile, directional terms such as upper side, lower side, one side, and the other side are used in relation to the orientation of the disclosed drawings. Since components of embodiments of the present invention may be positioned in a variety of orientations, directional terms are used for purposes of illustration and not limitation.

Also, terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms may be used for the purpose of distinguishing one component from another. For example, a first element may be termed a second element, and similarly, a second element may be termed a first element, without departing from the scope of the present invention.

1 is a diagram schematically showing a millimeter wave communication device according to an embodiment of the present invention.

Referring to FIG. 1 , a millimeter wave communication device 100 may include an array type detector unit structure 102 and a signal analyzer 104 . The millimeter wave communication device 100 may be a communication device capable of performing one or more operations of receiving and transmitting millimeter waves. Hereinafter, a case in which the millimeter wave communication device 100 receives a millimeter wave will be described as an example. Also, in the following, the array type detector unit structure 102 may be abbreviated as “unit structure 102”.

In an exemplary embodiment, the mmWave communication device 100 may be used in various imaging systems such as foreign material detection in food, non-destructive inspection, security inspection, and semiconductor inspection.

The unit structure 102 is an array type detector in which a plurality of antenna cells are arrayed. In an exemplary embodiment, unit structure 102 may be a 2x2 array detector. The unit structure 102 may be a basic configuration (unit configuration) for detecting a millimeter wave signal.

The unit structure 102 includes four antenna cells. Here, the antenna cell includes an antenna and may mean an area where the antenna is formed. The unit structure 102 may be one in which four antenna cells are arranged in a 2×2 shape. 2 is a diagram schematically illustrating a unit structure 102 according to an embodiment of the present invention. Referring to FIG. 2, the unit structure 102 includes a first antenna cell 102-1, a second antenna cell 102-2, a third antenna cell 102-3, and a fourth antenna cell 102-1. 4).

Here, the second antenna cell 102-2 is disposed on the right side of the first antenna cell 102-1, and the third antenna cell 102-3 is disposed below the second antenna cell 102-2. is disposed, and the fourth antenna cell 102-4 may be disposed to the left of the third antenna cell 102-3. At this time, the fourth antenna cell 102-4 may be disposed below the first antenna cell 102-1.

In the unit structure 102, the polarization directions of mutually adjacent antenna cells are provided vertically. That is, the polarization directions of mutually adjacent antenna cells in the unit structure 102 may differ by 90°. The polarization direction of an antenna cell may mean the polarization direction of an antenna disposed in the corresponding antenna cell.

Here, adjacent to each other may mean adjacent in the left-right direction or vertical direction of the antenna cell. That is, the polarization directions of the first antenna cell 102-1, the second antenna cell 102-2, and the fourth antenna cell 102-4 are provided perpendicularly, and the second antenna cell 102-2 and The polarization directions of the first antenna cell 102-1 and the third antenna cell 102-3 are provided vertically, and the third antenna cell 102-3, the second antenna cell 102-2 and the fourth The polarization direction of the antenna cell 102-4 is provided vertically, and the polarization directions of the fourth antenna cell 102-4, the first antenna cell 102-1, and the third antenna cell 102-3 are vertical. can be arranged.

In addition, the polarization direction of antenna cells arranged in a diagonal direction in the unit structure 102 in a 2×2 form may be provided in the same manner. That is, the polarization directions of the first antenna cell 102-1 and the third antenna cell 102-3 are the same, and the polarization direction of the second antenna cell 102-2 and the fourth antenna cell 102-4 is The polarization direction may be provided in the same way.

In FIG. 2, the polarizations of the first antenna cell 102-1 and the third antenna cell 102-3 are horizontally polarized, and the polarizations of the second antenna cell 102-2 and the fourth antenna cell 102-4 is shown to be vertical polarization, but is not limited thereto, and the polarizations of the first antenna cell 102-1 and the third antenna cell 102-3 are vertical polarization, and the second antenna cell 102-2 and The polarization of the fourth antenna cell 102-4 may be horizontally polarized.

According to the disclosed embodiment, by making the polarization directions of adjacent antenna cells different from each other by 90° in the 2×2 unit structure 102, it is possible to reduce signals coupled between adjacent antenna cells, Since the unit structure 102 receives both dual polarization (eg, horizontal polarization and vertical polarization), it is possible to maintain the magnitude of the received millimeter wave signal, thereby increasing the signal to noise ratio (SNR) do. That is, since noise between adjacent antenna cells can be reduced while maintaining the magnitude of the millimeter wave signal, the signal-to-noise ratio can be improved.

In addition, since the polarization directions of adjacent antenna cells are perpendicular to each other, it is possible to design by narrowing the distance between antenna cells, thereby overcoming physical limitations for increasing the separation characteristics between antenna cells.

The signal analyzer 104 may analyze the magnitude and phase of the millimeter wave signal detected by the unit structure 102 . The signal analyzer 104 can detect the magnitude of the millimeter wave signal and the polarization shift of the millimeter wave signal due to the unit structure 102 .

3 is a diagram for explaining polarization transition of a millimeter wave signal in one embodiment of the present invention.

Referring to FIG. 3 , when the millimeter wave transmitter 50 transmits the millimeter wave signal toward the target object 60, the millimeter wave signal before incident on the object 60 and the millimeter wave after passing through the object 60 The signal has a difference in its polarization direction. That is, when a millimeter wave signal incident with a linear polarization wave passes through the object 60, a polarization shift occurs due to the inherent directivity of the object 60, so that the polarization direction of the millimeter wave signal changes.

4 is a diagram showing a state in which the signal analyzer 104 analyzes the magnitude and phase of a millimeter wave signal in one embodiment of the present invention.

Referring to FIG. 4, the signal analyzer 104 calculates the amplitude of millimeter wave signals received from the first antenna cell 102-1 and the third antenna cell 102-3 having horizontal polarization of the unit structure 102. The magnitude (Vx) of the millimeter wave signal in the horizontal direction (x-axis direction) can be calculated.

In addition, the signal analyzer 104 sums the magnitudes of the millimeter wave signals received from the second antenna cell 102-2 and the fourth antenna cell 102-4 having vertical polarization of the unit structure 102 to determine the vertical direction The magnitude (Vy) of the millimeter wave signal (in the y-axis direction) can be calculated.

The signal analyzer 104 may calculate the magnitude of the millimeter wave signal detected by the unit structure 102 based on the magnitude (Vx) of the millimeter wave signal in the horizontal direction and the magnitude (Vy) of the millimeter wave signal in the vertical direction. . The signal analyzer 104 may calculate the magnitude (α) of the millimeter wave signal based on Equation 1 below.

(Equation 1)

In addition, the signal analyzer 104 calculates the phase of the millimeter wave signal detected by the unit structure 102 based on the magnitude (Vx) of the millimeter wave signal in the horizontal direction and the magnitude (Vy) of the millimeter wave signal in the vertical direction. can The signal analyzer 104 may calculate the phase φ of the millimeter wave signal based on Equation 2 below.

(Equation 2)

Here, since the unit structure 102 is composed of antenna cells having horizontal polarization and vertical polarization, the millimeter wave signal can be detected regardless of the polarization direction of the millimeter wave signal. In addition, since the magnitude (Vx) of the millimeter wave signal in the horizontal direction and the magnitude (Vy) of the millimeter wave signal in the vertical direction can be detected respectively, even if a polarization shift occurs in the millimeter wave signal, the original magnitude and polarization of the millimeter wave signal The shifted angle (i.e., how much the polarization is distorted) can also be obtained.

According to the disclosed embodiment, due to the unit structure 102 composed of antenna cells having horizontal polarization and vertical polarization, polarization shifted by an object can be recognized, and various polarizations including circular polarization can be detected. , it can be used for direction analysis and detection of objects.

5 is a graph comparing signal-to-noise ratio (SNR) between adjacent antenna cells in the unit structure 102 according to an embodiment of the present invention when the polarization direction is the same and when the polarization direction is vertical.

Referring to (a) of FIG. 5, a case in which the polarization direction between adjacent antenna cells in the unit structure 102 is horizontally polarized is all the same. In this case, noise due to coupling between adjacent antenna cells (eg, the first antenna cell 102-1, the second antenna cell 102-2, and the fourth antenna cell 102-4) It can be seen that the signal-to-noise ratio (SNR) is small.

On the other hand, referring to (b) of FIG. 5, the case where the polarization direction between adjacent antenna cells in the unit structure 102 is vertical is illustrated. In this case, noise due to coupling between adjacent antenna cells (eg, the first antenna cell 102-1, the second antenna cell 102-2, and the fourth antenna cell 102-4) It can be seen that the signal-to-noise ratio (SNR) increases.

6 is a diagram comparing the size of the unit structure 102 when the polarization direction between adjacent antenna cells is the same and when the polarization direction is vertical in the unit structure 102 according to an embodiment of the present invention.

Referring to (a) of FIG. 6, the case where the polarization direction between adjacent antenna cells in the unit structure 102 is horizontally polarized is all the same. In this case, in order to reduce interference between antenna cells, a first separation distance w1 is formed in the first direction, and a second separation distance w2 is also formed in a second direction perpendicular to the first direction.

That is, the first separation distance (w1) between the first antenna cell 102-1 and the fourth antenna cell 102-4 and the second antenna cell 102-2 and the third antenna cell 102-3 is and a second separation distance (w2) between the first antenna cell 102-1 and the second antenna cell 102-2 and the fourth antenna cell 102-4 and the third antenna cell 102-3 will form

On the other hand, referring to (b) of FIG. 6, the case where the polarization direction between adjacent antenna cells in the unit structure 102 is vertical is illustrated. In this case, since the direction of polarization between adjacent antenna cells is vertical and coupling between them is reduced, there is no need to provide a separate separation distance, and the antenna cells can be formed in contact with each other, so that the unit structure 102 size can be reduced.

Meanwhile, the 2×2 unit structure 102 can be expanded in horizontal and vertical directions. 7 is a diagram showing an expanded state of the unit structure 102 according to an embodiment of the present invention.

Referring to (a) of FIG. 7 , the 2×2 unit structure 102 may be extended to a 3×3 array detector. In this case, antenna cells adjacent to each other in the horizontal and vertical directions in the unit structure 102 may have polarization directions perpendicular to each other. In addition, antenna cells adjacent in a diagonal direction in the unit structure 102 may have the same polarization direction.

In addition, as shown in (b) of FIG. 7, the unit structure 102 can be extended to an array type detector in the form of n×m. Here, n and m may each be a natural number of 3 or greater. In this way, since the unit structure 102 can be easily expanded in an n×m form, the unit structure 102 can be enlarged to a large area to suit the imaging system to which the millimeter wave communication device 100 is applied.

8 is a diagram showing another embodiment in which the unit structure 102 according to an embodiment of the present invention is extended. Referring to FIG. 8 , in the unit structure 102 , signal input and output pads may be formed on the first edge 102a and the second edge 102b, respectively. In this case, the second side edge 102b may be a border vertically adjacent to the first side edge 102a.

Here, when the four unit structures 102 are rotated in a clockwise direction and arranged, the characteristics of the arrangement design in which the input and output pads are formed on the first side edge 102a and the second side edge 102b are maintained while maintaining It can be expanded to a 4x4 shape.

Although representative embodiments of the present invention have been described in detail above, those skilled in the art will understand that various modifications are possible to the above-described embodiments without departing from the scope of the present invention. . Therefore, the scope of the present invention should not be limited to the described embodiments and should not be defined, and should be defined by not only the claims to be described later, but also those equivalent to these claims.

100: millimeter wave communication device
102: array type detector unit structure
102a: first edge
102b: second side border
102-1: first antenna cell
102-2: second antenna cell
102-3: third antenna cell
102-4: fourth antenna cell
104: signal analyzer

Claims (17)

A millimeter wave communication device including an array type detector unit structure for detecting a millimeter wave signal,
The unit structure is
4 antenna cells are arranged in a 2x2 form, some of the 4 antenna cells have a first linear polarization, and others have a second linear polarization perpendicular to the first linear polarization.
The method of claim 1,
In the unit structure,
A millimeter wave communication device provided so that a polarization direction between antenna cells adjacent to each other in a left-right direction and a vertical direction is vertical.
The method of claim 2,
In the unit structure,
A millimeter wave communication device wherein polarization directions between antenna cells arranged in a diagonal direction are the same.
The method of claim 3,
The four antenna cells are formed by contacting each other between antenna cells disposed in a first direction and antenna cells disposed in a second direction perpendicular to the first direction.
The method of claim 3,
The millimeter wave communication device,
Further comprising input and output pads formed on a first side edge of the unit structure and a second side edge vertically adjacent to the first side edge,
A millimeter wave communication device, wherein the four unit structures are arranged while rotating in a clockwise direction and expanded in a 4×4 shape.
The method of claim 3,
The millimeter wave communication device,
The millimeter wave communication device further comprising a signal analyzer for analyzing the magnitude and phase of the millimeter wave signal detected by the unit structure.
The method of claim 6,
The signal analyzer,
A magnitude of a millimeter wave signal in a first direction is calculated by summing magnitudes of millimeter wave signals received from antenna cells having the first linear polarization among the four antenna cells, and calculating the magnitude of the second linear polarization among the four antenna cells. The magnitude of the millimeter wave signal in a second direction perpendicular to the first direction is calculated by summing the magnitudes of the millimeter wave signals received from the antenna cells having the first direction and the magnitude of the millimeter wave signal in the second direction A millimeter wave communication device for calculating the magnitude of the detected millimeter wave signal based on the magnitude of the wave signal.
The method of claim 7,
The signal analyzer,
A millimeter wave communication device that calculates the magnitude (α) of the detected millimeter wave signal by the following equation.
(mathematical expression)

V _x : Magnitude of millimeter wave signal in the first direction
V _y : Magnitude of millimeter wave signal in second direction
The method of claim 7,
The signal analyzer,
Wherein the millimeter wave communication device calculates the phase of the detected millimeter wave signal based on the magnitude of the millimeter wave signal in the first direction and the magnitude of the millimeter wave signal in the second direction.
The method of claim 9,
The signal analyzer,
The millimeter wave communication device calculating the phase (φ) of the detected millimeter wave signal by the following equation.
(Equation 2)

V _x : Magnitude of millimeter wave signal in the first direction
V _y : Magnitude of millimeter wave signal in second direction
The method of claim 1,
The unit structure is
A millimeter wave communication device in which an array of antenna cells is expanded in the form of n×m (n and m are each a natural number of 3 or greater).
The method of claim 11,
In the unit structure,
A millimeter wave communication device, wherein polarization directions between antenna cells adjacent to each other in left-right and up-down directions are vertical, and polarization directions between antenna cells arranged in a diagonal direction are the same.
An imaging system comprising the millimeter wave communication device according to any one of claims 1 to 12.
An array type detector unit structure for detecting a millimeter wave signal,
An arrayed detector unit structure in which four antenna cells are arranged in a 2×2 form, some of the four antenna cells have a first linear polarization, and others have a second linear polarization perpendicular to the first linear polarization .
The method of claim 14,
An array type detector unit structure in which a polarization direction between antenna cells adjacent to each other in a left-right direction and a vertical direction among the antenna cells is provided to be vertical.
The method of claim 15
Array-type detector unit structure, wherein the polarization direction between antenna cells disposed in a diagonal direction among the antenna cells is provided the same.
The method of claim 15
The unit structure is
An array type detector unit structure in which an array of antenna cells is extended in the form of n×m (n and m are each a natural number of 3 or greater).

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