Antenna device and radio device

Abstract

To provide an antenna device and a radio device that are suppress costs and have no restriction in service sites.SOLUTION: An antenna device includes: an antenna element having one end connected to a power supply point and arranged parallel to a metal surface at a predetermined distance from the surface; and a current induction element having a first element portion and a second element portion connected to the first element portion and non-parallel to the metal surface. Therein the current induction element is arranged such that an open end of the first element portion is capacitively coupled to an open end of the antenna element, and an open end of the second element portion is capacitively coupled to the metal surface.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an antenna device and a wireless device. [Background technology]

[0002] Antenna devices are becoming smaller. For example, there is an antenna that enhances the strength of vertically polarized waves by providing a parasitic antenna element with a vertical element portion that is arranged perpendicular to the ground surface near the end of a powered antenna element (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2021-175044 A Summary of the Invention [Problem to be solved by the invention]

[0004] The following analysis is provided by the present invention.

[0005] According to the technology disclosed in Patent Document 1, it is possible to improve antenna efficiency. Also, the length of the parasitic antenna element as a reflecting element can be shortened to less than half the wavelength of the radio wave to be transmitted and received, thereby preventing the antenna device from becoming large. Furthermore, since the powered antenna element and the parasitic antenna element are arranged in close proximity to each other, no additional noise countermeasures are required.

[0006] Because radio waves are blocked by a metal plate, they do not reach the other side of the metal plate well. Therefore, if a wireless device with an antenna device is installed close to a metal plate, the radio wave strength and the directivity of the antenna device on the other side of the metal plate will deteriorate. To avoid this phenomenon, it is necessary to take measures such as moving the metal plate away from the wireless device or changing the material of the metal plate.

[0007] For example, in the case of information and communication devices mounted on automobiles, wireless devices with antenna devices can be attached to the window glass or roof to ensure sufficient radio wave strength for communication with a base station antenna outside the vehicle. However, this requires longer cables, which leads to increased costs.

[0008] There is a need to ensure radio wave strength on the opposite side of the metal plate and mitigate degradation of the directivity of the antenna device without such measures or modifications.

[0009] The present invention has been made in view of the above circumstances, and has an object to provide an antenna device and a wireless device which are inexpensive and have no restrictions on where they can be used. [Means for solving the problem]

[0010] According to a first aspect of the present invention, An antenna element having one end connected to a feed point and disposed parallel to a metal surface at a predetermined distance from the metal surface; a current inducing element including a first element portion and a second element portion connected to the first element portion and non-parallel to the metal surface; An antenna device is provided in which the current induction element is positioned such that an open end of the first element portion is capacitively coupled to an open end of the antenna element and an open end of the second element portion is capacitively coupled to the metal surface.

[0011] According to a second aspect of the present invention, a ground portion having a reference potential; The antenna device as described above; The power supply point supplies power to the antenna device. 、 The ground portion is connected to the antenna element of the antenna device via the feeding point and provides the reference potential to the antenna element. A wireless device is provided. Effect of the Invention

[0012] According to the present invention, it is possible to provide an antenna device and a wireless device which can be used at low cost and without restrictions on the place of use. [Brief description of the drawings]

[0013] [Figure 1] 2A to 2C are explanatory diagrams illustrating an example of the configuration of a wireless device according to a first embodiment. [Diagram 2] 13(a) to 13(c) are explanatory diagrams illustrating the configuration of a wireless device for comparison. [Diagram 3] FIG. 13A is an explanatory diagram illustrating the results of a simulation using a wireless device for comparison, and FIGS. 13B to 13D are explanatory diagrams illustrating the results of a simulation using the wireless device of the first embodiment. [Figure 4] 13A to 13C are explanatory diagrams illustrating an example of the configuration of a wireless device according to a second embodiment. [Diagram 5] FIG. 11 is an explanatory diagram for explaining a simulation result of the wireless device according to the second embodiment. [Figure 6] 13(a) to 13(c) are explanatory diagrams illustrating an example of the configuration and arrangement of a wireless device according to a second embodiment. [Figure 7] 13(a) to 13(c) are explanatory diagrams illustrating configurations and arrangements of wireless devices for comparison. [Figure 8] FIG. 13A is an explanatory diagram for explaining the simulation results of a wireless device for comparison with the embodiment, and FIG. 13B is an explanatory diagram for explaining the simulation results of the wireless device of the embodiment. [Figure 9] FIG. 13A is an explanatory diagram illustrating an example of the arrangement of another example of the wireless device according to the second embodiment, and FIG. 13B is an explanatory diagram illustrating an example of the arrangement of another example of the wireless device for comparison. [Figure 10] 13A is an explanatory diagram for explaining the results of a simulation using a wireless device for comparison in another embodiment, and FIG. 13B is an explanatory diagram for explaining the results of a simulation using the wireless device of the other embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] An outline of one embodiment of the present invention (hereinafter, referred to as the present embodiment) will be described below with reference to the drawings. Note that the reference numerals in the drawings are given to each element for convenience as an example to aid in understanding, and are not intended to limit the present invention to the illustrated embodiment. In the following description, "A and / or B" is used to mean A or B, or A and B.

[0015] <<First embodiment>> The configuration of a wireless device 100 including an antenna device 100a according to this embodiment will be described. In the following description, a coordinate system will be used in which the surface of a ground portion described later is the XY plane, and the direction perpendicular to the surface of the ground portion is the Z axis. The X-axis and Y-axis directions will be described later.

[0016] [Wireless device configuration] Fig. 1(a) is a schematic perspective view of a wireless device 100 including an antenna device 100a according to this embodiment, Fig. 1(b) is a top view of the wireless device 100, and Fig. 1(c) is a view of the wireless device 100 as seen from the positive direction of the X-axis.

[0017] As shown in these figures, wireless device 100 of this embodiment includes a substrate 101a, a ground section (GND section) 101, a feeding point 102, and an antenna device 100a. GND section 101, feeding point 102, and antenna element 103 (described later) of antenna device 100a are formed on substrate 101a. Wireless device 100 of this embodiment is disposed a predetermined distance away from a predetermined surface (for example, a surface of metal plate 105 having a thickness of about 1 to 10 mm; a metal surface) and parallel to the surface.

[0018] In this embodiment, the GND section 101 is a rectangular plate-like conductive member. For example, it is made of copper or the like. The GND section 101 is an earth conductor for mounting electric circuits such as a transmission / reception circuit and a signal processing circuit. The GND section 101 is electrically connected to an antenna element 103 (to be described later) of the antenna device 100a via a power supply point 102 installed on one side of the rectangle, and provides a reference potential (ground potential) to the antenna element 103.

[0019] In the following description, as shown in Figures 1(a) to 1(c), the direction parallel to the side of GND section 101 on which power supply point 102 is provided is defined as the X-axis direction, and the direction perpendicular to this on the XY plane is defined as the Y-axis direction.

[0020] The feeding point 102 is an input terminal of a high frequency current to the antenna element 103 of the antenna device 100a and an output terminal of a high frequency current from the antenna element 103. The feeding point 102 has, for example, two terminals, one terminal connected to the antenna element 103 and the other terminal connected to the GND section 101.

[0021] The substrate 101a is a flat plate-like member made of an electrically insulating material such as resin, etc. The resin used is, for example, a glass cloth material, epoxy resin, etc.

[0022] Antenna device 100a includes antenna element 103 and current induction element 104, and transmits and receives target radio waves. Target radio waves include, for example, ultra-high frequency (UHF) and super high frequency (SHF). Ultra-high frequency waves have a wavelength of about 100 mm to 1000 mm, and microwaves have a wavelength of about 10 mm to 100 mm.

[0023] The antenna element 103 includes a parallel portion 103a parallel to the side of the GND portion 101 on which the feeding point 102 is disposed, and an orthogonal portion 103b perpendicular to the parallel portion 103a. As shown in FIGS. 1(a) to 1(c), the parallel portion 103a is disposed parallel to the X-axis, and the orthogonal portion 103b is disposed parallel to the Y-axis. One end of the orthogonal portion 103b is electrically connected to the feeding point 102. The end of the orthogonal portion 103b that is not connected to the feeding point 102 is connected to the parallel portion 103a. In this manner, the antenna element 103 has, for example, an inverted L shape in which the parallel portion 103a and the orthogonal portion 103b are connected perpendicularly.

[0024] Hereinafter, the end of antenna element 103 connected to feed point 102 will be referred to as a feed end. Also, the end of parallel part 103a of antenna element 103 that is not connected to orthogonal part 103b will be referred to as an open end.

[0025] The antenna element 103 is formed of a linear or elongated plate-like electrical conductor (hereinafter also simply referred to as a "conductor") made of copper, brass, aluminum, etc. The antenna element 103 may also be formed as a conductor pattern on the substrate 101a.

[0026] Wireless device 100 functions as an antenna by means of GND section 101 and antenna element 103. For this reason, it is desirable that the length of GND section 101 in the Y-axis direction plus the total length of antenna element 103 is approximately half the wavelength of the radio waves to be transmitted and received or less.

[0027] The current inducing element 104 includes a first element portion 104a disposed parallel to the xy plane, and a second element portion 104b having one end connected to the first element portion 104a.

[0028] An end of the first element portion 104a that is not connected to the second element portion 104b (hereinafter referred to as the open end of the first element portion 104a) is disposed near the open end of the parallel portion 103a of the antenna element 103.

[0029] The open end of the first element portion 104a and the open end of the parallel portion 103a are disposed at a distance that allows capacitive coupling. That is, the distance d1 between the open end of the first element portion 104a and the open end of the parallel portion 103a is a distance that allows a high-frequency current to be excited in the current inducing element 104 when power is supplied to the antenna element 103. It is desirable that the first element portion 104a and the parallel portion 103a are disposed so as to be perpendicular to each other on the XY plane.

[0030] An end of the second element portion 104b that is not connected to the first element portion 104a (hereinafter, referred to as an open end of the second element portion 104b) is disposed near the metal plate 105. The distance d2 between the open end of the second element portion 104b and the metal plate 105 is a distance at which a high-frequency current can be excited in the metal plate 105 when a high-frequency current is excited in the current induction element 104. That is, the open end of the second element portion 104b is disposed at a distance that allows capacitive coupling with the surface of the metal plate 105. The distance d2 is preferably 0.008 to 0.024 times the wavelength of the wavelength to be transmitted and received (excited high-frequency wave). For example, when the frequency of the high-frequency wave is 2.4 GHz, 1 to 3 mm is preferable, and when it is 800 MHz, 3 to 9 mm is preferable. When the frequency of the high-frequency wave is 2.4 GHz, 1 mm is particularly preferable.

[0031] In addition, the second element portion 104b is arranged non-parallel to the metal plate 105. For example, it is desirable that the second element portion 104b is arranged perpendicular to the plate surface of the metal plate 105. In other words, it is desirable that the second element portion 104b is arranged parallel to the Z axis. By arranging it perpendicularly, the maximum effect can be obtained regarding the electromagnetic coupling action. On the other hand, if the second element portion 104b of the current induction element 104 and the metal plate 105 are arranged parallel to each other, the effect is minimized.

[0032] The material of the current induction element 104 may be any conductive material. The current induction element 104 is formed of, for example, a linear or elongated plate-like conductor such as copper, brass, or aluminum. The current induction element 104 may be formed as a conductor pattern on a printed wiring board, or may be formed of copper tape. The resonant frequency of the current induction element 104 is preferably the same as the resonant frequency of the antenna element 103. The current induction element 104 is fixed, for example, by being attached to the side of a plastic housing.

[0033] The overall length of current induction element 104 is affected by the relationship between current induction element 104 and metal plate 105, but is desirably about half the wavelength of the radio waves to be transmitted and received.

[0034] [Wireless device operation] Next, the operation of the wireless device 100 of this embodiment will be described. In this embodiment, when a high-frequency current is supplied from the power supply point 102 to the antenna element 103 and flows through the antenna element 103, a high-frequency current is excited in the current induction element 104 by electromagnetic coupling since the parallel part 103a of the antenna element 103 and the first element part 104a of the current induction element 104 are close to each other. Note that the strength of the high-frequency current excited in the current induction element 104 depends on the strength of the high-frequency current flowing through the antenna element 103.

[0035] Furthermore, when a current flows through current induction element 104, since the open end of second element portion 104b of current induction element 104 and metal plate 105 are close to each other, a high-frequency current is excited in metal plate 105 by electromagnetic coupling. This increases the amount of radiation toward the opposite side of metal plate 105 from the surface to which the open end of second element portion 104b of current induction element 104 is close. In other words, the radio wave intensity on the opposite side increases.

[0036] [simulation] Next, a simulation result of the radiation characteristics of the metal plate 105 in the wireless device 100 of the above embodiment will be shown. Here, the radiation characteristics of the metal plate 105 when a high-frequency current with a frequency of 2.4 GHz is supplied from the feeding point 102 are shown.

[0037] In addition, as shown in FIG. 1(c), the wireless device 100 used in the simulation had a total length (L1+L2) of the current inducing element 104 of 0.4 wavelengths. That is, the total length (L1+L2) of the current inducing element 104 was 50 mm, of which the length (L1) of the first element portion 104a was 30 mm, and the length (L2) of the second element portion 104b was 20 mm. In addition, the distance (L2) between the wireless device 100 and the metal plate 105 was 20 mm. The distance d1 between the open end of the parallel portion 103a of the antenna element 103 and the open end of the first element portion 104a of the current inducing element 104 was 1 mm. In addition, the distance d2 between the open end of the second element portion 104b and the metal plate 105 was 1 mm. In addition, the size (length in the X-axis direction × length in the Y-axis direction) of the metal plate 105 was 300 mm × 300 mm, and the thickness was 5 mm.

[0038] For comparison, the radiation pattern is also shown for wireless device 200 having antenna device 200a that does not include current inducing element 104. As shown in Figures 2(a) to 2(c), the wireless device 200 used has the same configuration as wireless device 100 except that it does not include current inducing element 104. That is, in this wireless device 200, antenna device 200a includes only antenna element 103.

[0039] Fig. 3(a) shows a radiation pattern in the YZ plane of the wireless device 200. Also, Fig. 3(b) shows a radiation pattern in the YZ plane of the wireless device 100 of this embodiment.

[0040] Radiation from the surface of metal plate 105 opposite to the side where wireless device 100 (wireless device 200) is installed is shown in the 90° to 270° portion. Comparing the results of Fig. 3(a) and Fig. 3(b), the average gain of wireless device 200 in the 90° to 270° section is -20.4dBi, whereas the average gain of wireless device 100 of this embodiment in the 90° to 270° section is -12.9dBi. It can be seen that adding current inductive element 104 improves the average gain on the opposite surface of metal plate 105 by 7.5dB compared to the case without current inductive element 104.

[0041] 3(c) and 3(d) show, for reference, radiation patterns when the distance d2 between the open end of second element portion 104b and metal plate 105 is set to 2 mm and 3 mm, respectively. It can be seen that these cases also show improvements of 3.6 dB and 1.7 dB, respectively.

[0042] As described above, in this embodiment, the current induction element 104 is provided near the tip of the antenna device 100a built into the wireless device 100. This current induction element 104 is installed immediately inside the metal plate 105 from which it is desired to radiate radio waves to the outside. As a result, according to the antenna device 100a of the wireless device 100 of this embodiment, the current excited in the current induction element 104 can be made to flow on the opposite surface of the metal plate 105. Therefore, it is possible to ensure the radiation intensity of the radio waves from the wireless device 100 on the opposite side of the metal plate 105, and the directivity of the wireless device 100 is enhanced.

[0043] Therefore, according to the wireless device 100 of this embodiment, it is possible to reduce the shielding of radio waves caused by the metal plate 105, and performance can be ensured even if the wireless device 100 is installed near the metal plate 105. Therefore, it is possible to realize integration of the wireless device 100 having the antenna device 100a with a device that transmits and receives radio waves via the wireless device 100, and it is also possible to install the wireless device 100 on a member with high radio wave shielding, such as the metal plate 105. In other words, restrictions on the installation environment of the wireless device 100 are reduced.

[0044] <<Second embodiment>> A second embodiment of the present invention will be described. In an antenna device 110a of a wireless device 110 of this embodiment, an inductor 116 is added to a current inducting element 104 to achieve miniaturization. Hereinafter, this embodiment will be described with a focus on the configuration different from the first embodiment.

[0045] Fig. 4(a) is a schematic perspective view of a wireless device 110 including an antenna device 110a of this embodiment, Fig. 4(b) is a top view of the wireless device 110, and Fig. 4(c) is a view of the wireless device 110 as viewed from the positive direction of the X-axis.

[0046] As shown in these figures, wireless device 110 of this embodiment includes substrate 101a, ground section (GND section) 101, power feed point 102, and antenna device 110a. GND section 101, power feed point 102, and antenna element 103 (described later) of antenna device 110a are formed on substrate 101a. Wireless device 110 of this embodiment is disposed at a predetermined distance from metal plate 105 and parallel to the plate surface of metal plate 105. Details of GND section 101, power feed point 102, and substrate 101a are similar to those of the first embodiment.

[0047] The antenna device 110a of this embodiment includes an antenna element 103 and a current induction element 114, and transmits and receives a target radio wave. The target radio wave is the same as that of the first embodiment. The configuration of the antenna element 103 is also the same as that of the first embodiment.

[0048] The current inducing element 114 includes a first element portion 114a arranged parallel to the xy plane, a second element portion 114b having one end connected to the first element portion 114a, and an inductor 116. The details of the first element portion 114a and the second element portion 114b are the same as those of the same names in the first embodiment. The inductor 116 is attached to, for example, the second element portion 114b of the current inducing element 114.

[0049] In this embodiment, the inductor 116 is added to the current inductor 114 to increase the effective length of the current inductor 114. This allows the actual length of the current inductor 114 to be shortened.

[0050] The operation of the wireless device 110 of this embodiment is similar to the operation of the wireless device 100 of the first embodiment.

[0051] [simulation] The following shows the results of a simulation of the radiation characteristics of metal plate 105 in wireless device 110 of this embodiment. Here, similar to the first embodiment, the radiation characteristics of metal plate 105 are shown when a high-frequency current with a frequency of 2.4 GHz is supplied from feeding point 102.

[0052] The simulation conditions were basically the same as those of the first embodiment, except that, as shown in FIG. 4(c), the total length (L1+L2) of the current inducing element 114 was 30 mm, of which the length (L1) of the first element portion 114a was 10 mm, and the length (L2) of the second element portion 114b was 20 mm. An inductor 116 was attached to the second element portion 114b. The capacitance of the attached inductor 116 was 10 nH.

[0053] 5 shows a radiation pattern in the YZ plane of wireless device 110. As described above, radiation from the surface of metal plate 105 opposite to the side on which antenna device 110a is installed is shown in the 90° to 270° portion.

[0054] As shown in the figure, the average gain in the 90-degree to 270-degree section for the wireless device 110 of this embodiment is -13.5 dBi. This is an improvement of 6.9 dB compared to the wireless device 200 without the current inducing element 104 shown in Fig. 3(a). Also, when compared to the wireless device 100 of the first embodiment, it can be seen that the overall length of the current inducing element 114 is made 20 mm smaller (shorter) than the overall length of the current inducing element 104 of the antenna device 100a, and yet a result comparable to that of the wireless device 100 is obtained.

[0055] As described above, according to the wireless device 110 of this embodiment, the same effects as those of the first embodiment can be obtained. Furthermore, according to the wireless device 110 of this embodiment, the current inductor 116 is provided in the current inductor 114. This increases the effective length of the current inductor 114, so that the same effects as those of the first embodiment can be obtained with a shorter current inductor 114. Therefore, it is possible to achieve miniaturization while obtaining the same effects as those of the first embodiment.

[0056] <Example 1> Next, the results of a simulation of radiation characteristics when wireless device 110 of the second embodiment is installed on the inside of a pillar of an automobile are shown. The installed state is shown in Fig. 6(a) to Fig. 6(c).

[0057] Here, a metal plate 107 simulating an automobile pillar is used instead of the metal plate 105. The size (length in the X-axis direction x length in the Y-axis direction) of the metal plate 107 simulating a pillar is set to 600 mm x 60 mm. The other simulation conditions are the same as those of the second embodiment.

[0058] 7(a) to 7(c), the present embodiment also shows, as a comparative example, radiation characteristics when wireless device 200 is attached to the same metal plate 107. Simulation conditions other than the size of metal plate 107 are the same as those in the first embodiment.

[0059] Fig. 8(a) shows a radiation pattern in the YZ plane of the wireless device 200, and Fig. 8(b) shows a radiation pattern in the YZ plane of the wireless device 110 of the second embodiment. Here, the radiation characteristics of the metal plate 107 when a high-frequency current having the same frequency as in the above embodiment is fed from the feeding point 102 are shown.

[0060] 8(a) and 8(b), the average gain of the wireless device 200 in the 90° to 270° section is −9.9 dBi, whereas the average gain of the wireless device 110 of the second embodiment in the 90° to 270° section is −6.7 dBi. It can be seen that adding the current inductive element 114 improves the average gain on the opposite surface of the metal plate 107 by 3.2 dB compared to the case without the current inductive element 114.

[0061] <Example 2> Next, the results of a simulation of radiation characteristics when simulating a state in which the wireless device 110 of the second embodiment is installed on the top surface side of a ceiling router are shown. The ceiling router is, for example, an LED ceiling light equipped with a WiFi router function. Note that a metal plate 108 simulating the top surface of a ceiling light (ceiling router) is used instead of the above-mentioned metal plate 105. The installed state is shown in FIG. 9(a).

[0062] Here, the metal plate 108 is circular and has a diameter of 400 mm.

[0063] For comparison, in this embodiment, as shown in FIG. 9(b), the simulation results of the radiation characteristics when the wireless device 200 is attached to the same metal plate 108 are also shown.

[0064] Fig. 10(a) shows a radiation pattern in the YZ plane of the wireless device 200, and Fig. 10(b) shows a radiation pattern in the YZ plane of the wireless device 110 of the second embodiment. Here, the radiation characteristics of the metal plate 108 when a high-frequency current having the same frequency as in the above embodiment is fed from the feeding point 102 are shown.

[0065] 10(a) and 10(b), the average gain in the 90° to 270° section of the wireless device 200 is −21.5 dBi, whereas the average gain in the 90° to 270° section of the wireless device 110 of the second embodiment is −10.6 dBi. It can be seen that adding the current inductive element 114 improves the average gain on the opposite surface of the metal plate 108 by 10.9 dB compared to the case without the current inductive element 114.

[0066] <Variation 1> In the above embodiments, the antenna element 103 has been described as having an inverted L shape, but is not limited thereto. For example, the antenna element 103 may be a linear conductor. Even in this case, it is preferable that the current inducting elements 104 and 114 are disposed orthogonal to the antenna element 103.

[0067] <Variation 2> In addition, the first element portions 104a, 114a of the current induction elements 104, 114 are arranged on the same plane as the antenna element 103, but are not limited to this. It is sufficient that the open end of the parallel portion 103a of the antenna element 103 and the open end of the first element portion 104a of the current induction element 104 are at a distance that allows capacitive coupling between them and allows high-frequency current to be excited. For example, they may be arranged on a plane that is different from the plane on which the antenna element 103 is arranged and is parallel to the plane on which the antenna element 103 is arranged.

[0068] Although each embodiment of the present invention has been described above, the present invention is not limited to the above-mentioned embodiments, and further modifications, substitutions, and adjustments can be made without departing from the basic technical concept of the present invention. For example, the network configurations and the configurations of each element shown in the drawings are examples to help understand the present invention, and the present invention is not limited to the configurations shown in these drawings.

[0069] Some or all of the above-described embodiments and modified examples can be described as in the following supplementary forms, but are not limited to the following. (Appendix 1) An antenna element having one end connected to a feed point and disposed parallel to a metal surface at a predetermined distance from the metal surface; a current inducing element including a first element portion and a second element portion connected to the first element portion and non-parallel to the metal surface; An antenna device, wherein the current induction element is positioned so that an open end of the first element portion is capacitively coupled to an open end of the antenna element, and so that an open end of the second element portion is capacitively coupled to the metal surface. (Appendix 2) 2. The antenna device according to claim 1, The second element portion preferably includes an inductor. (Appendix 3) 3. The antenna device according to claim 1, It is desirable that the second element portion be disposed perpendicular to the metal surface. (Appendix 4) In the antenna device according to any one of Supplementary Note 1 to 3, An antenna device, wherein the vicinity of the open end of the antenna element and the first element portion are arranged on the same plane and perpendicular to each other. (Appendix 5) 5. The antenna device according to claim 1, The current inducing element preferably has a length of approximately half the wavelength of the target wavelength for transmission and reception. (Appendix 6) 6. The antenna device according to claim 1, The distance between the open end of the second element portion and the metal surface is desirably 0.008 to 0.024 times the target wavelength for transmission and reception. (Appendix 7) 7. The antenna device according to claim 1, The antenna element preferably has an inverted L shape. (Appendix 8) a ground portion having a reference potential; An antenna device according to any one of claims 1 to 7; A wireless device comprising: a feeding point that feeds power to the antenna device.

[0070] The disclosures of the above patent documents and the like are incorporated herein by reference. Within the framework of the entire disclosure of the present invention (including the scope of claims), modifications and adjustments of the embodiments and examples are possible based on the basic technical ideas. Furthermore, within the framework of the disclosure of the present invention, various combinations and selections of the various disclosed elements (including each element of each claim, each element of each embodiment or example, each element of each drawing, etc.) are possible. In other words, the present invention naturally includes various modifications and corrections that a person skilled in the art would be able to make based on the entire disclosure including the scope of claims and the technical ideas. In particular, with regard to the numerical ranges described in this specification, any numerical value or subrange included in the range should be interpreted as being specifically described even if not otherwise specified. [Explanation of symbols]

[0071] 100: wireless device, 100a: antenna device, 101: GND portion, 101a: substrate, 102: power supply point, 103: antenna element, 103a: parallel portion, 103b: orthogonal portion, 104: current induction element, 104a: first element portion, 104b: second element portion, 105: metal plate, 107: metal plate, 108: metal plate, 110: wireless device, 110a: antenna device, 114: current inducting element, 114a: first element portion, 114b: second element portion, 116: inductor, 200: radio device, 200a: antenna device

Claims

1. An antenna element having one end connected to a feed point and disposed parallel to a metal surface at a predetermined distance from the metal surface; a current inducing element including a first element portion and a second element portion connected to the first element portion and non-parallel to the metal surface; An antenna device, wherein the current induction element is positioned so that an open end of the first element portion is capacitively coupled to an open end of the antenna element, and so that an open end of the second element portion is capacitively coupled to the metal surface.

2. 2. The antenna device according to claim 1, The second element portion comprises an inductor.

3. 2. The antenna device according to claim 1, The second element portion is disposed perpendicular to the metal surface.

4. 2. The antenna device according to claim 1, An antenna device, wherein the vicinity of the open end of the antenna element and the first element portion are arranged on the same plane and perpendicular to each other.

5. 2. The antenna device according to claim 1, The antenna device, wherein the current induction element has a length of approximately half the wavelength of a target wavelength for transmission and reception.

6. 2. The antenna device according to claim 1, An antenna device, wherein the distance between the open end of the second element portion and the metal surface is 0.008 to 0.024 times the target wavelength for transmission and reception.

7. 2. The antenna device according to claim 1, The antenna device, wherein the antenna element has an inverted L shape.

8. a ground portion having a reference potential; An antenna device according to any one of claims 1 to 7; a feeding point for feeding power to the antenna device, The ground section is connected to the antenna element of the antenna device via the feeding point, and provides the reference potential to the antenna element.

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