Built-in vehicle antenna

Abstract

To provide a built-in antenna for a vehicle which can be manufactured with low manufacturing complexity and low manufacturing cost and has a high radiation gain in all directions. [Solution] A built-in antenna for a vehicle according to the present invention includes a substrate having a power supply portion formed on an upper portion and a ground surface formed on a lower portion; a first radiating plate electrically connected to the power supply portion and extending from the substrate at an angle in a first direction; a second radiating plate spaced apart from the first radiating plate, electrically connected to the power supply portion and extending from the substrate at an angle in a second direction opposite to the first direction; and a third radiating plate electrically connected to the ground surface, spaced apart from the first and second radiating plates, and positioned so as to be electromagnetically coupled to the first and second radiating plates, wherein the widths of the first and second radiating plates gradually increase as they move away from the substrate.

Description

[Technical Field]

[0001] The present invention relates to an antenna, and more particularly to a built-in antenna for a vehicle. [Background technology]

[0002] With the development of communication technology, various communications are now being carried out through vehicles. Shark fin antennas are commonly used as vehicle antennas for vehicle communications. Shark fin antennas are attached to the vehicle roof to communicate with external devices. However, since shark fin antennas protrude from the vehicle roof, they can spoil the aesthetic appearance of the vehicle. Therefore, there has been a recent increase in demand for built-in antennas that are embedded inside the vehicle roof.

[0003] However, built-in vehicle antennas require a higher radiation gain than shark fin antennas, which means that they are more difficult to design and costly to manufacture than shark fin antennas. Conventional built-in vehicle antennas mainly use cone-shaped radiators, but these cone-shaped radiators are difficult to manufacture, which has been a major factor in increasing the manufacturing cost and difficulty of built-in vehicle antennas. Summary of the Invention [Problem to be solved by the invention]

[0004] SUMMARY OF THE INVENTION An object of the present invention is to provide a built-in vehicle antenna that can be manufactured with low manufacturing complexity and low manufacturing cost and has a high radiation gain. [Means for solving the problem]

[0005] The built-in antenna for a vehicle according to the present invention includes a substrate having a feeder formed on an upper portion and a ground plane formed on a lower portion; a first radiating plate electrically connected to the feeder and extending from the substrate at an angle in a first direction; a second radiating plate spaced apart from the first radiating plate, electrically connected to the feeder, and extending from the substrate at an angle in a second direction opposite to the first direction; and a third radiating plate electrically connected to the ground plane, spaced apart from the first and second radiating plates, and positioned to be electromagnetically coupled to the first and second radiating plates, wherein the first and second radiating plates have a structure in which their widths gradually increase as they become farther from the substrate.

[0006] An end of the first radiation plate is bent to form a first bent portion, and an end of the second radiation plate is bent to form a second bent portion. The third radiation plate includes a ground connection portion electrically connected to the ground plane, and a fan-shaped extension portion extending from the ground connection portion and gradually increasing in width. The third radiating plate further includes a third bent portion formed by bending an end portion thereof, and the height of the third radiating plate is greater than the heights of the first radiating plate and the second radiating plate.

[0007] A portion of the third bent portion vertically overlaps with a portion of the first bent portion and a portion of the second bent portion. The first radiation plate and the second radiation plate have the same shape and are arranged to have a symmetrical structure.

[0008] The feed part includes a feed line, a first round open stub and a second round open stub protruding from both sides of the feed line, and a feed plate connected to the feed line, and the first radiation plate and the second radiation plate are electrically coupled to the feed plate. The first and second radiating plates have rectangular slots formed therein. The built-in vehicle antenna further includes a fourth radiating plate spaced apart from the first and second radiating plates, electrically connected to the feeding portion, and extending from the substrate at an angle inclined toward a third direction perpendicular to the first and second directions.

[0009] Another built-in antenna for a vehicle according to the present invention includes a substrate having a feeder formed on an upper portion and a ground plane formed on a lower portion; a first radiating plate electrically connected to the feeder and extending from the substrate at an angle inclined in a first direction; a second radiating plate spaced apart from the first radiating plate, electrically connected to the feeder, and extending from the substrate at an angle inclined in a second direction opposite to the first direction; and a third radiating plate electrically connected to the ground plane, spaced apart from the first and second radiating plates, and positioned to be electromagnetically coupled to the first and second radiating plates. an end of the first radiating plate is bent to form a first bent portion, an end of the second radiating plate is bent to form a second bent portion, and the third radiating plate includes a ground connecting portion electrically connected to the ground plane, a fan-shaped extension portion extending from the ground connecting portion and gradually increasing in width, and a third bent portion formed by bending the end portion, wherein the height of the third radiating plate is higher than the heights of the first radiating plate and the second radiating plate, and a portion of the third bent portion vertically overlaps with a portion of the first bent portion and a portion of the second bent portion. [Effects of the Invention]

[0010] The built-in vehicle antenna of the present invention has the advantages of being able to be manufactured with low manufacturing complexity and low manufacturing cost, and having a high radiation gain in all directions. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a perspective view showing the structure of a built-in vehicle antenna according to an embodiment of the present invention; [Figure 2]1 is a first side view of a built-in vehicle antenna according to an embodiment of the present invention. [Figure 3] FIG. 2 is a second side view of the built-in vehicle antenna according to one embodiment of the present invention. [Figure 4] FIG. 2 is a top plan view of an antenna according to an embodiment of the present invention. [Figure 5] 1 is a diagram illustrating a structure of a power supply part formed on a substrate according to an embodiment of the present invention; [Figure 6] 10 is a graph comparing the return loss of the antenna according to an embodiment of the present invention with the return loss when the third radiating plate does not have a fan-shaped structure. [Figure 7] 10 is a graph comparing the return loss of an antenna according to an embodiment of the present invention with that of a reference antenna; DETAILED DESCRIPTION OF THE INVENTION

[0012] To understand the operational advantages and objectives of the present invention, a preferred embodiment of the present invention will be illustrated.

[0013] The present invention will be described in detail below by describing preferred embodiments with reference to the accompanying drawings. However, the present invention may be embodied in various different forms and is not limited to the described embodiments. In order to clearly explain the present invention, parts that are not relevant to the description will be omitted, and the same reference numerals in the drawings indicate the same elements.

[0014] Throughout the specification, when a part "includes" a certain element, this does not mean excluding other elements and may further include other elements, unless otherwise specified. Furthermore, terms such as "... unit," "... machine," "module," and "block" used in the specification refer to a unit that processes at least one function or operation, and can be embodied in hardware, software, or a combination of hardware and software.

[0015] FIG. 1 is a perspective view showing the structure of a built-in vehicle antenna according to one embodiment of the present invention, FIG. 2 is a first side view of the built-in vehicle antenna according to one embodiment of the present invention, and FIG. 3 is a second side view of the built-in vehicle antenna according to one embodiment of the present invention.

[0016] 1 to 3, a built-in vehicle antenna according to an embodiment of the present invention includes a first radiating plate 100, a second radiating plate 200, a third radiating plate 300, a fourth radiating plate 400, and a substrate 500. The first to fourth radiating plates 100, 200, 300, and 400 are fixed on the substrate 500. The first radiating plate 100 and the second radiating plate 200 have the same shape and are electrically coupled to a feeding part (not shown in FIGS. 1 to 3) formed on the top of the substrate 500.

[0017] The first radiating plate 100 to the fourth radiating plate 400 are fabricated by molding conductive metal plates. The first radiating plate extends from the substrate 500 at an angle in a first direction. The first radiating plate 100 has a structure in which its width gradually increases as it moves away from the substrate. The first radiating plate 100 has the narrowest width at its lower end where it is joined to the substrate and the widest width at its upper end. The upper end of the first radiating plate 100 is bent, and a first bent portion 110 of the first radiating plate 100 is parallel to the substrate. A first slot 120 is formed in the center of the first radiating plate 100, and the first slot 120 has a rectangular structure.

[0018] The second radiating plate 200 is formed opposite the first radiating plate 100, and the second radiating plate 200 and the first radiating plate 100 are arranged in a symmetrical structure. As a result, the second radiating plate 200 extends at an angle in the second direction. The second radiating plate 200 also has a structure in which its width gradually increases as it moves away from the substrate. The second radiating plate 200 has the narrowest width at its lower end where it is joined to the substrate and the widest width at its upper end. The upper end of the second radiating plate 200 is bent, and the second bent portion 210 of the second radiating plate 200 is also parallel to the substrate. A second slot 220 is formed in the center of the second radiating plate 200.

[0019] The first radiating plate 100 and the second radiating plate 200 are electrically connected to a power supply on the substrate 500 to receive a power supply signal and radiate the received power supply signal to the outside. It is important for a built-in vehicle antenna to have omnidirectional radiation characteristics. The present invention ensures omnidirectional radiation characteristics through the first radiating plate 100 and the second radiating plate 200, which have a symmetrical structure and gradually widen in width. The first radiating plate 100 and the second radiating plate 200 are simply formed from conductive metal plates, so they can be manufactured with simple manufacturing complexity and at low manufacturing costs compared to existing conical radiators.

[0020] Meanwhile, the built-in vehicle antenna of the present invention further includes a third radiating plate. The third radiating plate 300 includes a ground connection portion 310, a fan-shaped extension portion 320, and a third bent portion 330. The ground connection portion 310 is electrically connected to a ground plane formed on the bottom of the substrate 500. The ground connection portion 310 and the fan-shaped extension portion 320 are integral, and the fan-shaped extension portion 320 extends from the end of the ground connection portion 310. The fan-shaped extension portion 320 has a gradually increasing width, similar to the first radiating plate 100 and the second radiating plate 200. The fan-shaped extension portion 320 continuously extends in width to a specific point. As a result, the fan-shaped extension portion 320 has a hexagonal structure, and the portion from the end of the extension to the end point has a rectangular structure. The structure in which the width of the fan-shaped extension 320 of the third radiation plate 300 is increased contributes to improving the return loss of the antenna of the present invention, and the fan-shaped extension 320 can ensure an appropriate radiation gain.

[0021] Meanwhile, the upper end of the third radiating plate 300 is bent to form a third bent portion 330. The third bent portion 330 is also parallel to the substrate 500. The height of the third radiating plate 300 is higher than the first and second radiating plates 100 and 200, and therefore the third bent portion 300 is formed at a higher position than the first and second bent portions 110 and 210.

[0022] The third radiating plate 300 is not directly connected to the feed portion but is connected to the ground plane, so that a feed signal is not directly provided to the third radiating plate 300. The third radiating plate 300 assists radiation of the antenna of the present invention by coupling the radiated signals of the first radiating plate 100 and the second radiating plate 200. In order to couple the radiated signals of the first radiating plate 100 and the second radiating plate 200 to the third radiating plate 300, the third bent portion 330 is arranged adjacent to the first bent portion 110 and the second bent portion 210, and a portion of the third bent portion 330 is arranged to vertically overlap a portion of the first bent portion 110 and the second bent portion 210.

[0023] 4 is a top plan view of an antenna according to an embodiment of the present invention. As shown in FIGS. 2 and 4, a portion of the third bent portion 330 is vertically overlapped with a portion of the first bent portion 110 and a portion of the second bent portion 210, and the bent portions are adjacent to each other so as to be electromagnetically coupled, thereby enabling electromagnetic coupling from the first radiating plate 100 and the second radiating plate 200 to the third radiating plate 300.

[0024] 2 shows a structure in which the first to third radiating plates 100 to 300 penetrate the substrate 500. However, the illustrated substrate penetration structure is for mechanically fixing the first to third radiating plates 100 to 300, and the substrate penetration structure is not necessarily required. The first radiating plate 100 and the second radiating plate 200 may be connected to a feeding part on the upper part of the substrate 500, and the third radiating plate 300 may be connected to a ground plane on the lower part of the substrate 500.

[0025] The fourth radiating plate 400 is electrically connected to the power supply part on the upper side of the substrate 500 and extends in a third direction while tilting at a specific angle. The fourth radiating plate 400 also has a fan-shaped structure whose width gradually increases, like the first radiating plate 100 and the second radiating plate 200. The fourth radiating plate 400 is a radiating plate for radiating signals with a wider bandwidth than the first radiating plate 100 and the second radiating plate 200. If a wider bandwidth signal is not required, the fourth radiating plate 400 may not be provided. Preferably, the first direction in which the first radiating plate 100 is tilted and the second direction in which the second radiating plate is tilted are opposite to each other, and the third direction in which the fourth radiating plate is tilted is perpendicular to the first and second directions.

[0026] 5 is a diagram illustrating the structure of a feeder formed on a substrate according to an embodiment of the present invention. As shown in FIG. 5, the feeder formed on a substrate according to an embodiment of the present invention includes a feed line 600, a first round open stub 610, a second round open stub 620, and a feed plate 630. The power supply line 600 may be electrically connected to a power supply line or a power supply connector that provides a power supply signal. For example, the power supply line or the power supply connector may be connected to an end of the power supply line 600, and the power supply signal may be provided through the power supply line 600.

[0027] A first round open stub 610 and a second round open stub 620 are coupled to the feed line 600. The first round open stub 610 protrudes in a rounded structure toward the left side of the feed line 600, and the second round open stub 620 protrudes in a rounded structure toward the right side of the feed line 600. The first round open stub 610 and the second round open stub 620 preferably have a symmetrical structure with respect to the feed line 600. By forming the first round open stub 610 and the second round open stub 620 symmetrically, return loss is improved and resonance occurs in the intended frequency band.

[0028] A feed plate 630 is formed at the end of the feed line 600. As shown in Fig. 5, the feed line 600 preferably has a circular shape. The first radiating plate 100, the second radiating plate 200, and the fourth radiating plate 400 are coupled to the feed plate 630. As described above, the feed portion as shown in Fig. 5 is formed on the top of the substrate 500.

[0029] 6 is a graph comparing the return loss of an antenna according to an embodiment of the present invention with the return loss when the third radiating plate does not have a fan-shaped structure. For reference, the graph shown in FIG. 6 is a graph showing the return loss when the third radiating plate is not provided. In FIG. 6, graph 1 is a graph showing the return loss of an antenna according to an embodiment of the present invention, and graph 2 is a graph showing the return loss when the third radiating plate does not have a fan-shaped structure and has the same width.

[0030] As shown in Figure 6, when the radiating plate does not have a fan-shaped structure, it can be seen that it has low return loss in the low frequency band. However, when the radiating plate has a fan-shaped extension with a gradually increasing width as in the present invention, it can be seen that it has high return loss in the low frequency band, resulting in high radiation efficiency in the low frequency band and relatively wideband characteristics. Therefore, as can be seen from Figure 6, when radiation is performed through the first and second radiating plates 100 and 200 as in the present invention, when the third radiating plate has a fan-shaped structure with a gradually increasing width, it has the intended return loss characteristics.

[0031] 7 is a graph comparing the return loss of an antenna according to an embodiment of the present invention with that of a reference antenna, where Graph 1 shows the return loss of the antenna according to an embodiment of the present invention, Graph 2 shows the return loss when the third radiating plate is removed from the antenna according to an embodiment of the present invention, and Graph 3 shows the return loss when the third radiating plate and two round open stubs are removed from the antenna according to an embodiment of the present invention.

[0032] As shown in the third graph of Figure 7, if the two rounded open stubs and the third radiating plate are both removed, it is difficult to obtain adequate return loss and form a resonant frequency at the desired resonance point. As shown in the second graph of Figure 7, it is possible to form a resonant frequency in the desired band using the two rounded open stubs. However, it is also possible to confirm that the absence of the third radiating plate results in low return loss. From the graph of Figure 7, it can be seen that the radiating plate with the fan-shaped extension of the present invention ensures the desired return loss, thereby improving the radiation gain.

[0033] Although the present invention has been described with reference to the embodiments shown in the drawings, these are merely illustrative, and those skilled in the art will recognize that various modifications and equivalent embodiments are possible. Therefore, the true technical scope of protection of the present invention should be determined by the technical spirit of the claims. [Explanation of symbols]

[0034] 100 First Radiation Plate 110 1st bending section 120 1st Slot 200 Second Radiation Plate 210 2nd bending section 220 Second Slot 300 Third Radiation Plate 310 Ground connection 320 Fan-type extension 330 3rd bending section 400 4th Radiation Plate 500 boards 600 Power Supply Line 610 Round type first open stub 620 Round type second open stub 630 Power Supply Plate

Claims

1. a substrate having a power supply portion formed on an upper portion thereof and a ground plane formed on a lower portion thereof; a first radiation plate electrically coupled to the feed portion and extending from the substrate at an angle in a first direction; a second radiation plate spaced apart from the first radiation plate, electrically coupled to the feeding portion, and extending from the substrate at an angle inclined toward a second direction opposite to the first direction; a third radiating plate electrically connected to the ground plane, spaced apart from the first radiating plate and the second radiating plate, and disposed at a position capable of being electromagnetically coupled to the first radiating plate and the second radiating plate, The vehicle built-in antenna, wherein the first radiation plate and the second radiation plate have a structure in which their widths gradually increase as they move away from the substrate.

2. 2. The built-in antenna for a vehicle according to claim 1, wherein an end of the first radiation plate is bent to form a first bent portion, and an end of the second radiation plate is bent to form a second bent portion.

3. 3. The built-in antenna for a vehicle according to claim 2, wherein the third radiation plate includes a ground connection portion electrically connected to the ground surface, and a fan-shaped extension portion extending from the ground connection portion and gradually increasing in width.

4. 4. The vehicle-mounted built-in antenna according to claim 3, wherein the third radiating plate further includes a third bent portion formed by bending an end portion thereof, and the height of the third radiating plate is greater than the heights of the first radiating plate and the second radiating plate.

5. 5. The built-in antenna for a vehicle according to claim 4, wherein a portion of the third bent portion vertically overlaps with a portion of the first bent portion and a portion of the second bent portion.

6. The vehicle built-in antenna according to claim 1, wherein the first radiation plate and the second radiation plate have the same shape and are arranged to have a symmetrical structure.

7. 7. The built-in antenna for a vehicle of claim 6, wherein the feeder part includes a feeder line, first and second round open stubs protruding from both sides of the feeder line, and a feeder plate connected to the feeder line, wherein the first and second radiation plates are electrically coupled to the feeder plate.

8. The built-in antenna for a vehicle according to claim 1, wherein the first radiation plate and the second radiation plate have rectangular slots formed therein.

9. 2. The built-in antenna for a vehicle according to claim 1, further comprising a fourth radiation plate spaced apart from the first radiation plate and the second radiation plate, electrically connected to the power supply portion, and extending from the substrate at an angle inclined toward a third direction perpendicular to the first direction.

10. a substrate having a power supply portion formed on an upper portion thereof and a ground plane formed on a lower portion thereof; a first radiation plate electrically coupled to the feed portion and extending from the substrate at an angle in a first direction; a second radiation plate spaced apart from the first radiation plate, electrically coupled to the feeding portion, and extending from the substrate at an angle inclined toward a second direction opposite to the first direction; a third radiating plate electrically connected to the ground plane, spaced apart from the first radiating plate and the second radiating plate, and disposed at a position capable of being electromagnetically coupled to the first radiating plate and the second radiating plate, an end of the first radiation plate is bent to form a first bent portion, and an end of the second radiation plate is bent to form a second bent portion; the third radiation plate includes a ground connection portion electrically connected to the ground plane, a fan-shaped extension portion extending from the ground connection portion and gradually increasing in width, and a third bent portion formed by bending an end portion, and the third radiation plate has a height greater than that of the first radiation plate and the second radiation plate; The vehicle built-in antenna, wherein a portion of the third bent portion vertically overlaps with a portion of the first bent portion and a portion of the second bent portion.

11. The built-in antenna for a vehicle according to claim 10, wherein the first radiation plate and the second radiation plate have a structure in which their widths gradually increase as they move away from the substrate.

12. The built-in vehicle antenna according to claim 11, wherein the first radiation plate and the second radiation plate have the same shape and are arranged to have a symmetrical structure.

13. 11. The built-in antenna for a vehicle of claim 10, wherein the feeder part includes a feeder line, first and second round open stubs protruding from both sides of the feeder line, and a feeder plate connected to the feeder line, wherein the first and second radiation plates are electrically coupled to the feeder plate.

14. The built-in antenna for a vehicle according to claim 12, wherein the first radiation plate and the second radiation plate have rectangular slots formed therein.

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