KR102158031B1 - Microstrip stacked patch antenna - Google Patents

Abstract

The present invention relates to a microstrip stack (MICROSTRIP STACKED) patch antenna usable in a radar module.
The microstrip stack patch antenna according to the present invention includes a first substrate on which a plurality of first microstrip patches are disposed on an upper surface, a second microstrip patch is disposed on the upper surface, and is located under the first substrate. A second substrate provided with a ground layer on a surface thereof, and a third substrate disposed under the second substrate and having a first power supply pad receiving a frequency signal supplied to the lower surface thereof, wherein the second microstrip patch comprises: Radiating a frequency signal applied from the power supply pad through a first via hole connecting the second microstrip patch and the power supply pad through the second and third substrates, and coupled to the first microstrip patch It is prepared to supply.

Description

Microstrip stack patch antenna {MICROSTRIP STACKED PATCH ANTENNA}

The present invention relates to a microstrip stack (MICROSTRIP STACKED) patch antenna usable in a radar module.

In recent years, as the use of portable devices has become common and communication technology has become common, research to solve the battery and power cord problems that are obstacles to miniaturization of circuits, and to realize power supply and battery charging wirelessly, and a ubiquitous sensor that can be used anytime, anywhere Research on the technology for power supply is actively in progress.

In particular, wireless power transmission technology is attracting a lot of attention as one of the 10 promising technologies in the future society.

Rectenna, which is used for wireless power transmission, is a compound word of a rectifier and an antenna, and is composed of an antenna that accepts an RF signal, a rectifier diode, and a load resistance. It refers to an element that converts DC power through a rectifier circuit.

These rectennas are applied to UWB radar modules and the like, and typically include sinuous, vivaldi, anti-vivaldi, and patch antennas. Currently, patch antennas that are easy to design and manufacture and can be miniaturized are mainly used.

In the case of a general patch antenna, the antenna radiating unit and the reflecting unit are manufactured to be spaced apart by a predetermined interval using air as a medium.

In this case, the antenna radiating unit and the reflecting unit are coupled using screws or the like, and when the distance between the antenna radiating unit and the reflecting unit is not constant due to assembly tolerances when assembling the antenna, there is a problem that the antenna characteristics are rapidly deteriorated.

In addition, in the case of a conventional patch antenna, as the size of the antenna increases, the antenna characteristic deterioration phenomenon increases due to side lobes generated from the antenna, and thus it is difficult to reduce the size of the antenna.

An object of the present invention is to provide a microstrip stack patch antenna that does not use air as a medium.

In addition, an object of the present invention is to provide a microstrip stack patch antenna capable of suppressing the generation of side lobes as microstrip patches are arranged in a multilayer structure.

In addition, an object of the present invention is to provide a microstrip stack patch antenna that can be manufactured in a small size and can improve a bandwidth compared to a conventional patch antenna.

In order to solve the above technical problem, according to an aspect of the present invention, a first substrate on which a plurality of first microstrip patches are disposed on an upper surface, a second substrate located under the first substrate, and a second A second substrate on which a microstrip patch is disposed, a ground layer is provided on a lower surface thereof, a third substrate on which a first power supply pad is disposed on a lower surface of the second substrate and receives a frequency signal from the outside; and A microstrip stack patch antenna including a first via hole penetrating the second and third substrates and connecting the second microstrip patch and the power supply pad is provided.

Here, the first microstrip patch and the second microstrip patch are not directly connected by an arbitrary feed line, and the frequency signal applied to the second microstrip patch through the first feed line is transmitted to the second The microstrip patch is configured to radiate and supply the coupling to the first microstrip patch.

In addition, a first ground pad may be disposed on the lower surface of the third substrate, and the first ground pad may be grounded with the ground layer through a second via hole.

In addition, a coaxial connector for supplying a frequency signal to the first power supply pad is connected, and the coaxial connector includes a coaxial cable supplying a frequency signal, a second power supply pad in contact with the first power supply pad, and the first ground pad. And a second ground pad in contact with.

In an embodiment, when viewed from the top of the microstrip stack patch antenna, the first microstrip patch may be disposed to overlap a partial region of the second microstrip patch.

In this case, the edge of the first microstrip patch may be disposed to overlap the edge of the second microstrip patch.

In another modification, as the edge of the second microstrip patch has a diagonal shape connecting two adjacent sides to each other, a band width, which is a broadband characteristic of the antenna, may be increased.

In addition, the first microstrip patch disposed on the upper surface of the first substrate is provided at a corner of a virtual square to form a ten-shaped separation space, and the first microstrip patch disposed on the upper surface of the second substrate The second microstrip patch may be provided on the second substrate to face the cross-shaped spaced space.

Additionally, by further including at least one parasitic patch disposed on the upper surface of the second substrate so as to be spaced apart from the second microstrip patch, radiation characteristics of a frequency signal supplied to the second microstrip patch may be improved.

In this case, the parasitic patch may be disposed between two adjacent first microstrip patches when viewed from the top of the ultra-wideband patch antenna, and the frequency signal radiated from the second microstrip patch is transmitted to the first microstrip. Couplings can be supplied as strip patches.

As the microstrip stack patch antenna according to the present invention adopts a structure that does not include an air medium layer, it is possible to solve the problem that antenna characteristics are degraded according to assembly tolerances.

In addition, in the microstrip stack patch antenna according to the present invention, it is possible to improve antenna characteristics by suppressing the generation of side lobes by arranging the microstrip patches in a multilayer structure.

Additionally, the microstrip stack patch antenna according to the present invention has an advantage in that it is possible to increase the bandwidth of the band width by improving the radiation characteristics of the frequency signal through the microstrip patch and the parasitic patch arranged in a multilayer structure.

In addition, the microstrip stack patch antenna according to the present invention has an advantage in that it is easy to change a broadband frequency through the application of a parasitic patch and a shape change of the microstrip patch.

In addition, in the microstrip stack patch antenna according to the present invention, the connector receiving the frequency signal from the outside is connected to the rear surface of the microstrip stack patch antenna in the form of a coaxial connector to supply the frequency signal. There is an advantage in that it is possible to widen the radiation angle and further suppress the occurrence of side lobes.

Through this, when the generation of side lobes is suppressed, the gain of the antenna can be improved, the detection range of the radar module can be improved, and the reliability of measurement and detection results can be improved.

In particular, the microstrip stack patch antenna according to the present invention can be applied to implement a UWB radar system for detecting obstacles or dynamic objects in outdoor and night environments, and through this, a radar sensor for dynamic object detection applicable to vehicles or heavy equipment. It is possible to implement a module (eg, rear detection sensor, etc.).

1 shows a top surface of a microstrip stack patch antenna according to an embodiment of the present invention as a transmittance.
FIG. 2 shows an upper surface of a first substrate applied to the microstrip stack patch antenna shown in FIG. 1.
3 and 4 illustrate an upper surface of a second substrate positioned under the first substrate.
5 illustrates an upper surface of a third substrate positioned under the second substrate, and FIG. 6 illustrates a lower surface of the third substrate.
7 is a cross-sectional view of the microstrip stack patch antenna illustrated in FIG. 1.
8 is a plan view showing an upper surface of a coaxial connector applied to the microstrip stack patch antenna shown in FIG. 1.
9 is a side view of the coaxial connector shown in FIG. 8.
10 is a plan view showing a lower surface of the coaxial connector shown in FIG. 8.
11 is a graph showing a broadband characteristic (S11 parameter) of the microstrip stack patch antenna shown in FIG. 1.
12 and 13 are graphs showing radiation patterns at 7.5GHz of the microstrip stack patch antenna shown in FIG. 1.
14 to 17 are transmission diagrams illustrating top surfaces of a microstrip stack patch antenna according to various embodiments of the present disclosure.

Certain terms are defined herein for convenience in order to make the invention easier to understand. Unless otherwise defined herein, scientific and technical terms used in the present invention will have the meanings commonly understood by those of ordinary skill in the art. In addition, unless otherwise specified in context, terms in the singular form are to include their plural forms, and the terms in the plural form are to be understood as including the singular form thereof.

Hereinafter, a microstrip stack patch antenna according to various embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a view showing the top surface of a microstrip stack patch antenna according to an embodiment of the present invention as a transmittance, and FIG. 2 shows the top surface of a first substrate applied to the patch antenna shown in FIG. 4 illustrates an upper surface of a second substrate positioned under the first substrate.

In addition, FIG. 5 shows the upper surface of the third substrate positioned under the second substrate, FIG. 6 shows the lower surface of the third substrate, and FIG. 7 shows the microstrip stack patch antenna shown in FIG. It shows a cross section.

1 to 7, the patch antenna 100 according to an embodiment of the present invention includes a first substrate 110 and a first substrate having a plurality of first microstrip patches 111 disposed on an upper surface thereof. 110), the second microstrip patch 121 is disposed on the upper surface, and the second substrate 120 and the second substrate 120 are provided with a ground layer 122 on the lower surface. It is located and is composed of a third substrate 130 on which a first power supply pad 133 that receives a frequency signal from the outside is disposed on a lower surface.

A coaxial connector 140 including a coaxial cable is in contact with the first power supply pad 133 to supply a frequency signal to the microstrip stack patch antenna. At this time, the frequency signal supplied through the coaxial connector 140 passes through the second substrate 120 and the third substrate 130 to connect the first power supply pad 133 and the second microstrip patch 121. It is applied to the second microstrip patch 121 through the first via hole 131.

At this time, since the first microstrip patch 111 and the second microstrip patch 121 are not directly connected by an arbitrary feed line, the second microstrip patch 121 through the first via hole 131 The frequency signal applied to is coupled and supplied to the first microstrip patch 111 through radiation by the second microstrip patch 121.

The first substrate 110, the second substrate 120, and the third substrate 130 may be printed circuit boards formed of a dielectric material such as Teflon. According to an embodiment of the present invention, the thickness, dielectric constant, and dielectric loss of the first substrate 110, the second substrate 120, and the third substrate 130 may be the same. However, the dielectric constant and dielectric loss values of the first substrate 110, the second substrate 120, and the third substrate 130, as well as the thickness thereof, may be variously designed as necessary. For example, the bandwidth and antenna gain factor of the hatch antenna may be adjusted by adjusting the dielectric constant, dielectric loss value, and thickness of the first substrate 110, the second substrate 120, and the third substrate 130. will be.

Referring to FIG. 2, a plurality of first microstrip patches 111 are disposed on the upper surface of the first substrate 110, and the first microstrip patches 111 are disposed to be spaced apart from each other. It is preferable from the side. For example, a plurality of first microstrip patches 111 disposed on the first substrate 110 may be provided at the corners of a virtual square to form a ten-shaped spaced space.

The first microstrip patch 111 may be formed on the upper surface of the first substrate 110 in a printed circuit manner, or may be attached by manufacturing a conductive material such as copper foil in an appropriate shape. In addition, the first microstrip patch 111 may be implemented for the X band, which is a high frequency band between 8 GHz and 12 GHz.

The first microstrip patch 111 plays a role of radiating electromagnetic waves to the outside or receiving a wireless signal from the outside, and at this time, the first microstrip patch 111 directly supplies a frequency signal through an arbitrary feed line. It is not received and is arranged to be supplied indirectly by the second microstrip patch 121.

3 and 4, a second microstrip patch 121 is disposed on the upper surface of the second substrate 120. The second microstrip patch 121 may be implemented for the X band, which is a high-frequency band between 8 GHz and 12 GHz, and is connected to the first via hole 131 to apply a frequency signal supplied through the first feeding pad 133 It is configured to receive.

The position of the second microstrip patch 121 is not particularly determined, but, for example, a plurality of first microstrip patches 111 disposed on the first substrate 110 have a ten-shaped separation space. When provided at the corners of the virtual square to form, the second microstrip patch 121 is preferably disposed at a position corresponding to the center of the ten-shaped spaced space.

In addition, the shape of the second microstrip patch 121 may have a quadrangle similar to the first microstrip patch 111, but is not limited thereto. If necessary, the shapes of the first microstrip patch 111 and the second microstrip patch 121 may be modified.

As shown in FIG. 4, according to a modified example of the present invention, the corners of the second microstrip patch 121 have a diagonal shape connecting two adjacent sides to each other, and accordingly, the second microstrip patch 121 It can have an octagonal shape. In this case, it is possible to further increase a band width, which is a broadband characteristic of the antenna, than when the second microstrip patch 121 has a square shape.

As described above, the first microstrip patch 111 and the second microstrip patch 121 are not directly connected by an arbitrary power supply line, and through the first via hole 131, the second microstrip patch ( The frequency signal applied to 121 is radiated toward the top, and accordingly, is configured to be coupled and supplied to the first microstrip patch 111.

The first microstrip patch 111 receives the frequency signal radiated from the second microstrip patch 121 without being directly applied to the frequency signal through an arbitrary feed line, thereby receiving the frequency signal from the first microstrip patch 111. It is possible to improve the broadband characteristics of the patch antenna by expanding the range of the radiated frequency band.

In addition, there is an advantage in that it is possible to improve the separation of the vertical and horizontal polarizations through the indirect power feeding method through the second microstrip patch 121 and to suppress the occurrence of side lobes of the patch antenna.

As shown in FIG. 1, according to an embodiment of the present invention, when viewed from the top of the microstrip stack patch antenna, the first microstrip patch 111 is formed with a partial region of the second microstrip patch 121. It can be arranged to overlap. In this case, the edge of the first microstrip patch 111 may be disposed to overlap the edge of the second microstrip patch 121.

The frequency signal radiated toward the first substrate 110 by the current induced in the second microstrip patch 121 according to the above-described arrangement structure of the first microstrip patch 111 and the second microstrip patch 121 Is coupled and supplied to a plurality of first microstrip patches 111 arranged so that the edges and partial regions thereof overlap, and through this, it is possible to increase the bandwidth of the frequency signal to be coupled and copied.

A plate-shaped ground layer 122 is provided under the second substrate 120. Accordingly, the frequency signal supplied from the lower portion through the coaxial connector 140 is radiated to the first microstrip patch 111 and/or the second microstrip patch 121 without passing through the first via hole 131. It is possible to avoid interference problems.

In this case, the ground layer 122 is entirely provided under the second substrate 120, and the first via hole 131 is not only the second substrate 120 and the third substrate 130, but also the ground layer 122 The second microstrip patch 121 and the first power feeding pad 133 are connected to each other by passing through.

As the third substrate 130 is additionally disposed under the ground layer 122, it is possible to further improve the grounding characteristics.

5 to 7, the first via hole 131 passes through the second substrate 120 and the third substrate 130 and is connected to the second microstrip patch 121, and the second via hole 134 Is grounded with the ground layer 122 through the third substrate 130. In this case, it is preferable to arrange a plurality of second via holes 134 to improve the grounding characteristics.

Referring to FIG. 6 showing the lower surface 130 ′ of the third substrate, the first via hole 131 is disposed in the via pad 132, and the via pad 132 is electrically connected to the first power supply pad 133. It is connected by Here, the first power supply pad 133 contacts the second power supply pad of the coaxial connector 140 to be described later. In addition, a plurality of second via holes 134 are disposed in a predetermined area, and a first ground pad 135 is disposed around the second via holes 134. Here, the first ground pad 134 is grounded with the ground layer 122 through the second via hole 134 and at the same time contacts the second ground pad of the coaxial connector 140 to be described later.

FIG. 8 is a plan view showing an upper surface of the coaxial connector 140 applied to the microstrip stack patch antenna 100 shown in FIG. 1, and FIG. 9 is a side view of the coaxial connector 140 shown in FIG. 8, and FIG. 10 Is a plan view showing a lower surface of the coaxial connector 140 shown in FIG. 8.

8 to 10, the coaxial connector 140 is disposed at the center of the body 141 and the body 141, and contacts a coaxial cable 144 for supplying a frequency signal and a first power supply pad 133 And a second power supply pad 142 and a second ground pad 143 in contact with the first ground pad 135.

According to the present invention, by placing the coaxial connector 140 of the above-described structure under the second microstrip patch 121, the frequency signal supplied by the coaxial connector 140 is not leaked and the second microstrip patch 121 ) To be supplied efficiently. In addition, the coaxial connector 140 is grounded with the first ground pad 135 disposed under the third substrate 130 through the second ground pad 143, and the first ground pad 135 is a second via hole. There is an advantage in that it is possible to significantly improve the grounding characteristics by being grounded to the ground layer 122 via 134. Accordingly, it is possible to effectively suppress the occurrence of side lobes.

11 is a graph showing the broadband characteristics (S11 parameter) of the microstrip stack patch antenna shown in FIG. 1, and FIGS. 12 and 13 are graphs showing the radiation pattern at 7.5 GHz of the microstrip stack patch antenna shown in FIG. 1 It is a graph. Here, FIG. 12 is a radiation pattern measured from an upper or lower side of the microstrip stack patch antenna shown in FIG. 1, and FIG. 13 is a radiation pattern measured from a left or right side of the microstrip stack patch antenna shown in FIG. 1.

Referring to FIG. 11, a frequency band of about 6.87 GHz to about 8.63 GHz and about 1.76 GHz is provided, and the indirect power feeding method of the first microstrip patch 111 and the second microstrip patch 121 and the third It can be seen that broadband characteristics are secured through a power supply method using the coaxial connector 140 disposed on the rear surface of the substrate 130.

In addition, the microstrip stack patch antenna according to an embodiment of the present invention is about 6.87 GHz despite not applying a harmonic cut-off filter for blocking a second harmonic that may occur when the harmonic component is re-radiated through the antenna again. It can be seen that harmonics do not occur in a frequency band outside the range of about 8.63 GHz.

Referring to FIGS. 12 and 13, it can be seen that the generation of side loads is considerably suppressed as the side lobe level as well as the radiated signal strength (Main lobe magnitude) is -20 dB or less. In addition, it can be seen that the angular width is also quite excellent as 77.3 deg and 65.0 deg.

14 to 17 are transmission diagrams illustrating top surfaces of a microstrip stack patch antenna according to various embodiments of the present disclosure.

14 and 17, at least one parasitic patch 123 disposed to be spaced apart from the second microstrip patch 121 may be additionally disposed on the second substrate 120.

The parasitic patch 123 may be attached by fabricating a conductive material such as copper foil that is the same as the second microstrip patch 121 in an appropriate shape.

Unlike the second microstrip patch 121, the parasitic patch 123 does not directly receive the frequency signal from the second feed line 202, but instead receives the frequency signal radiated from the second microstrip patch 121 in an indirect feed method. It is configured to receive a coupling supply.

The parasitic patch 123 coupled with the frequency signal is similar to the second microstrip patch 121 and re-emits the frequency signal toward the top. Accordingly, the bandwidth of the frequency signal applied to the first microstrip patch 111 It plays a role in broadening.

In addition, as shown in FIGS. 16 and 17, the corners of the second microstrip patch 121 have a diagonal shape connecting two adjacent sides, and accordingly, the second microstrip patch 121 has an octagonal shape. Can have.

As the shape of the edge of the second microstrip patch 121 is modified as shown in FIGS. 7A and 7B, it is possible to further increase a band width, which is a broadband characteristic of the antenna.

In addition, as shown in FIGS. 15 and 17, when the microstrip stack patch antenna 100 is viewed from the top, the edge of the second microstrip patch 121 does not overlap with the first microstrip patch 111. It should be understood that the arrangement is also within the scope of the present invention.

In the above, an embodiment of the present invention has been described with reference to the drawings, but those of ordinary skill in the art, within the scope of not departing from the spirit of the present invention contained in the claims, the addition of components, Various modifications and changes may be made to the present invention by changes, deletions or additions, and it will be said that this is also included within the scope of the present invention.

Claims (10)

A first substrate on which a plurality of first microstrip patches are disposed on an upper surface;
A second substrate positioned under the first substrate, a second microstrip patch disposed on an upper surface, and a ground layer disposed on a lower surface;
A third substrate positioned under the second substrate and having a first power supply pad disposed on a lower surface thereof to receive a frequency signal from the outside; And
A first via hole passing through the second substrate and the third substrate to connect the second microstrip patch and the power supply pad;
Including,
The second microstrip patch radiates a frequency signal applied from the power supply pad through a first via hole and is coupled to the first microstrip patch, and
Further comprising a first ground pad disposed on the lower surface of the third substrate,
The first ground pad is grounded with the ground layer through a second via hole,
A coaxial connector for supplying a frequency signal to the first feeding pad is connected,
The coaxial connector,
A coaxial cable for supplying a frequency signal;
A second power supply pad in contact with the first power supply pad; And
Including a second ground pad in contact with the first ground pad
Microstrip stack patch antenna.
delete delete delete The method of claim 1,
When viewed from the top of the microstrip stack patch antenna,
The first microstrip patch is disposed to overlap with a partial region of the second microstrip patch,
Microstrip stack patch antenna.
The method of claim 5,
When viewed from the top of the microstrip stack patch antenna,
The edge of the first microstrip patch is arranged to overlap with the edge of the second microstrip patch,
Microstrip stack patch antenna.
The method of claim 6,
The edge of the second microstrip patch has a diagonal shape connecting two adjacent sides to each other,
Microstrip stack patch antenna.
The method of claim 1,
When viewed from the top of the microstrip stack patch antenna,
The first microstrip patch disposed on the upper surface of the first substrate is provided at the corner of a virtual square to form a ten-shaped space,
The second microstrip patch disposed on the upper surface of the second substrate is provided on the second substrate to face the cross-shaped separation space,
Microstrip stack patch antenna.
A first substrate on which a plurality of first microstrip patches are disposed on an upper surface;
A second substrate positioned under the first substrate, a second microstrip patch disposed on an upper surface, and a ground layer disposed on a lower surface;
A third substrate positioned under the second substrate and having a first power supply pad disposed on a lower surface thereof to receive a frequency signal from the outside; And
A first via hole passing through the second substrate and the third substrate to connect the second microstrip patch and the power supply pad;
Including,
The second microstrip patch radiates a frequency signal applied from the power supply pad through a first via hole and is coupled to the first microstrip patch, and
Further comprising at least one parasitic patch disposed to be spaced apart from the second microstrip patch on an upper surface of the second substrate,
The parasitic patch re-emits a frequency signal radiated from the second microstrip patch and provides coupling to the first microstrip patch,
Microstrip stack patch antenna.
The method of claim 9,
When viewed from the top of the microstrip stack patch antenna,
The parasitic patch is disposed between two first microstrip patches adjacent to each other,
Microstrip stack patch antenna.

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