Antenna device

Abstract

The antenna device (1) includes: a first ground component (15); one or more first antennas (11) connected to the first ground component (15) and resonating in a first frequency band; a second ground component (25) disposed at a position adjacent to the first ground component (15) with a gap (60) therebetween and connected to a ground portion different from the first ground component (15); one or more second antennas (21) connected to the second ground component (25) and resonating in a second frequency band; one or more first filters (31) connecting the first ground component (15) and the second ground component (25) to attenuate signals in the first frequency band; and one or more second filters (32) connecting the first ground component (15) and the second ground component (25) at a position different from the one or more first filters (31), with less attenuation of signals in the first frequency band compared to the one or more first filters (31).

Description

Technical Field

[0001] The present invention relates to an antenna device. Background Art

[0002] In recent years, with the development of wireless communication, multiple antennas based on multiple standards such as Wireless LAN (Local Area Network) and Bluetooth (registered trademark) have been mounted on an electronic device. As such an antenna for wireless communication in multiple frequency bands, a multi-band antenna that can transmit and receive signals in multiple frequency bands with one antenna has been proposed (for example, Patent Document 1, etc.).

[0003] The dual-band antenna described in Patent Document 1 includes a linear portion and a spiral coil portion. The spiral coil portion functions as a choke coil for high-frequency band signals and functions as a part of a miniaturized antenna for low-frequency band signals. Thus, in Patent Document 1, it is desired to realize a dual-band antenna that is small and has different effective electrical lengths according to the frequency.

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2000-59130 Summary of the Invention

[0007] Problems to be Solved by the Invention

[0008] The present invention provides an antenna device having two antennas that resonate in mutually different frequency bands and capable of adjusting the directivity of each antenna.

[0009] Means for Solving the Problems

[0010] An antenna device according to one aspect of the present invention includes: a first grounding member connected to a grounding portion; one or more first antennas connected to the first grounding member and resonating in a first frequency band; a second grounding member disposed adjacent to the first grounding member with a gap therebetween and connected to a grounding portion different from the first grounding member; one or more second antennas connected to the second grounding member and resonating in a second frequency band different from the first frequency band; one or more first filters connecting the first grounding member and the second grounding member and attenuating signals in the first frequency band; and one or more second filters connecting the first grounding member and the second grounding member at a position different from the one or more first filters and having less attenuation of signals in the first frequency band than the one or more first filters.

[0011] Advantages of the Invention

[0012] According to the present invention, there can be provided an antenna device having two antennas resonating in mutually different frequency bands and capable of adjusting the directivity of each antenna. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic plan view showing the structure of the antenna device of Embodiment 1.

[0014] Figure 2A It is a circuit diagram showing a structural example of the first filter of Embodiment 1.

[0015] Figure 2B It is a circuit diagram showing the normal structure of the first filter of Embodiment 1.

[0016] Figure 3 It is a schematic plan view showing the structure of the antenna device of Embodiment 2.

[0017] Figure 4 It is a schematic plan view showing the structure of the antenna device of Embodiment 3.

[0018] Figure 5 It is a schematic plan view showing the structure of the antenna device of Embodiment 4.

[0019] Figure 6 It is a schematic plan view showing the structure of the antenna device of Embodiment 5.

[0020] Figure 7 It is a schematic side view showing the structure of the antenna device of Embodiment 5.

[0021] Figure 8 It is a schematic perspective view showing the structure of the antenna device of Embodiment 6.

[0022] Figure 9 It is a schematic plan view showing the structure of the first layer portion of the antenna device of Embodiment 6.

[0023] Figure 10 It is a schematic plan view showing the structure of the second layer portion of the antenna device of Embodiment 6.

[0024] Figure 11 It is a schematic plan view showing the structure of the gap of the antenna device of a modification of Embodiment 6. DETAILED DESCRIPTION OF THE INVENTION

[0025] Hereinafter, the embodiments will be specifically described with reference to the drawings.

[0026] In addition, the embodiments described below represent general or specific examples. Therefore, the numerical values, shapes, materials, constituent elements, arrangement positions and connection forms of the constituent elements, steps, order of steps, etc. shown in the following embodiments are examples and are not intended to limit the present invention.

[0027] In addition, each drawing is a schematic diagram and is not necessarily strictly drawn. In addition, in each drawing, the same reference numerals are given to the same constituent parts.

[0028] (Embodiment 1)

[0029] The antenna device of Embodiment 1 will be described.

[0030] [1-1. Structure]

[0031] First, use Figure 1 to describe the structure of the antenna device of Embodiment 1. Figure 1 is a schematic plan view showing the structure of the antenna device 1 of the present embodiment. In Figure 1 , a plan view of the substrate 50 of the antenna device 1 is shown in a plan view.

[0032] The antenna device 1 is an antenna that transmits and receives signals of multiple frequency bands. In the present embodiment, the antenna device 1 transmits and receives signals of a first frequency band and a second frequency band different from the first frequency band. The first frequency band and the second frequency band are not particularly limited. In the present embodiment, the first frequency band is a frequency band lower than the second frequency band. Specifically, the first frequency band and the second frequency band are the 2.4 GHz band and the 5 GHz band, respectively. Thus, the antenna device 1 can be used as a dual-band antenna for the 2.4 GHz band and the 5 GHz band based on the standards of wireless LAN. As Figure 1 shown, the antenna device 1 includes a first ground component 15, a first antenna 11, a second ground component 25, a second antenna 21, a first filter 31, and a second filter 32. In the present embodiment, the antenna device 1 further includes a substrate 50.

[0033] The first ground component 15 is a conductive component connected to the ground portion. The shape of the first ground component 15 is not particularly limited. In the present embodiment, the first ground component 15 has a film shape and is disposed in a predetermined area on the substrate 50. As the first ground component 15, for example, a copper film disposed and patterned on the substrate 50 can be used.

[0034] The second grounding component 25 is disposed adjacent to the first grounding component 15 with a gap 60 therebetween, and is a conductive component connected to a grounding portion different from the first grounding component 15. The shape of the second grounding component 25 is not particularly limited. In the present embodiment, the second grounding component 25 is disposed in an area adjacent to the area where the first grounding component 15 is disposed on the substrate 50, and has a film shape. As the second grounding component 25, for example, a copper film or the like disposed and patterned on the substrate 50 can be used. The gap 60 is a portion that electrically insulates the first grounding component 15 and the second grounding component 25. In the present embodiment, the gap 60 is a void having a width of about 1 mm. The width of the gap 60 is not limited to about 1 mm. The width of the gap 60 can be, for example, 1 / 500 or more and about 1 / 50 or less of the wavelength corresponding to the first frequency band or the second frequency band. In addition, the width of the gap 60 can be 1 / 200 or more of the wavelength corresponding to the first frequency band or the second frequency band, and can also be 1 / 100 or less.

[0035] The first antenna 11 is connected to the first grounding component 15 and is an antenna that resonates in the first frequency band. In the present embodiment, the first antenna 11 is an inverted F antenna that resonates in the 2.4 GHz band. The first antenna 11 is formed of a conductive component and has a main body portion 11a, a power supply portion 11b, and a short circuit portion 11c. In the present embodiment, the first antenna 11 is formed by a metal plate made of aluminum, copper, or the like. The main body portion 11a is a portion that is separated from the first grounding component 15 and extends along the main surface of the substrate 50 on which the first grounding component 15 is disposed. In the present embodiment, as Figure 1 shown, the main body portion 11a has a rectangular shape in a plan view of the substrate 50. The sum of the electrical lengths of two adjacent sides of the rectangular main body portion 11a is about 1 / 4 of the wavelength corresponding to the first frequency band. The power supply portion 11b is a portion to which a signal in the first frequency band is supplied. The power supply portion 11b is connected to the main body portion 11a and is not directly connected to the first grounding component 15. In addition, the power supply portion 11b is connected to the first grounding component 15 via the main body portion 11a and the short circuit portion 11c. The power supply portion 11b penetrates the first grounding component 15 and the substrate 50, for example, and a signal is supplied on the back surface of the substrate 50 (that is, the main surface on the back side of the main surface on which the first grounding component 15 is disposed). The short circuit portion 11c is a portion that shorts the first grounding component 15 and the main body portion 11a. The short circuit portion 11c is connected to the main body portion 11a and the first grounding component 15.

[0036] The second antenna 21 is connected to the second ground component 25 and is an antenna that resonates in a second frequency band different from the first frequency band. In the present embodiment, the second antenna 21 is an inverted-F antenna that resonates in the 5 GHz band. The second antenna 21 is formed of a conductive member and has a main body portion 21a, a power supply portion 21b, and a short-circuit portion 21c. In the present embodiment, the second antenna 21 is formed of a metal plate made of aluminum, copper, or the like. The main body portion 21a is a portion that is separated from the second ground component 25 and extends along the main surface of the substrate 50 on which the second ground component 25 is disposed. In the present embodiment, as Figure 1 shown, the main body portion 21a has a rectangular shape in the plan view of the substrate 50. The sum of the electrical lengths of two adjacent sides of the rectangular main body portion 21a is approximately 1 / 4 of the wavelength corresponding to the second frequency band. The power supply portion 21b is a portion to which a signal in the second frequency band is supplied. The power supply portion 21b is connected to the main body portion 21a and is not directly connected to the second ground component 25. In addition, the power supply portion 21b is connected to the second ground component 25 via the main body portion 21a and the short-circuit portion 21c. The power supply portion 21b penetrates the second ground component 25 and the substrate 50, for example, and a signal is supplied on the back surface of the substrate 50 (that is, the main surface on the back side of the main surface on which the second ground component 25 is disposed). The short-circuit portion 21c is a portion that short-circuits the second ground component 25 and the main body portion 21a. The short-circuit portion 21c is connected to the main body portion 21a and the second ground component 25.

[0037] The substrate 50 is an electrically insulating plate-like member that serves as a base of the antenna device 1. On one main surface of the substrate 50, the first antenna 11, the first ground component 15, the second antenna 21, the second ground component 25, the first filter 31, and the second filter 32 are disposed. In the present embodiment, the substrate 50 is a rectangular plate-shaped dielectric. The substrate 50 is, for example, a glass epoxy substrate.

[0038] The first filter 31 connects the first ground component 15 and the second ground component 25 and is a frequency filter that attenuates a signal in the first frequency band. In the present embodiment, the first filter 31 attenuates a signal in the first frequency band more than a signal in the second frequency band. The first filter 31 is disposed at a position where the distance from the first antenna 11 is 1 / 2 or less of the wavelength corresponding to the first frequency band and the distance from the second antenna 21 is 1 / 2 or less of the wavelength corresponding to the second frequency band.

[0039] As the first filter 31 that attenuates a signal in the first frequency band, for example, a high-pass filter having a capacitor can be used. The first filter 31 is connected to the first ground component 15 and the second ground component 25 across a gap 60. Use Figure 2A to illustrate an example of the first filter 31. Figure 2A is a circuit diagram showing a structural example of the first filter 31 of the present embodiment. As Figure 2AAs shown, the first filter 31 has two capacitors C1 and C2 connected in series, and an inductor L connected between the two capacitors C1 and C2 across the lines. For example, the capacitance of the capacitors C1 and C2 is 0.3 pF, and the inductance of the inductor L is 5.3 nH. Additionally, it is also possible that the capacitance of the capacitors C1 and C2 is 0.36 pF, and the inductance of the inductor L is 3 nH. With the first filter 31 having such a circuit structure, a frequency filter that attenuates the signals in the first frequency band and allows the signals in the second frequency band to pass can be realized. Additionally, as the first filter 31, a circuit in which the Figure 2A shown circuits are connected in series multiple times can also be used. Additionally, the structure of the first filter 31 is not limited to this. Hereinafter, Figure 2B is used to describe the normal circuit structure of the first filter 31. Figure 2B is a circuit diagram showing the normal structure of the first filter 31 of the present embodiment. As Figure 2B shown, the first filter 31 has two capacitors C1 and C2 connected in series, two inductors L1 and L2, and capacitors C3 and an inductor L3 connected in parallel. By adjusting the capacitance of each capacitor and the inductance of each inductor, a first filter 31 with desired frequency characteristics can be realized. Additionally, as the first filter 31, a circuit in which the Figure 2B shown circuits are connected in series multiple times can also be used. Additionally, the first filter 31 can also be a so-called metamaterial having the Figure 2A and Figure 2B shown circuit structure.

[0040] The second filter 32 connects the first ground component 15 and the second ground component 25 at a position different from that of the first filter 31, and is a frequency filter with less attenuation of the signals in the first frequency band compared to the first filter 31. In the present embodiment, the second filter 32 allows the signals in the first frequency band to pass. For example, in the second filter, the attenuation of the signals in the first frequency band can be 3 dB or more less than that of the first filter 31. Additionally, in the second filter 32, the signals in the second frequency band can be attenuated. In the present embodiment, the second filter 32 attenuates the signals in the second frequency band more than the signals in the first frequency band. The second filter 32 is arranged at a position where the distance from the first antenna 11 is less than or equal to 1 / 2 of the wavelength corresponding to the first frequency band and the distance from the second antenna 21 is less than or equal to 1 / 2 of the wavelength corresponding to the second frequency band.

[0041] As the second filter 32 that attenuates the signals in the second frequency band, for example, a low-pass filter having an inductor can be used. The second filter 32 is connected to the first ground component 15 and the second ground component 25 across the gap 60. The second filter 32 is also generally composed of the same Figure 2BThe circuit representation shown. The circuit structure of the second filter 32 of the present embodiment is appropriately determined according to the required frequency characteristics. In addition, as the second filter 32, a circuit in which a plurality of circuits shown in Figure 2B are connected in series may also be used. In addition, the second filter 32 may also be a so-called metamaterial having a circuit structure as shown in Figure 2B .

[0042] [1-2. Function and effect]

[0043] Next, the function and effect of the antenna device 1 of the present embodiment will be described. The directivity of each of the first antenna 11 and the second antenna 21 of the antenna device 1 of the present embodiment depends not only on the shapes of the first antenna 11 and the second antenna 21, but also on the shape and size of the connected ground portion. For example, the directivity of the first antenna 11 depends on the shape and size of the connected first ground member 15. Therefore, in order to adjust the directivity of the first antenna 11, it is possible to consider adjusting the shape and size of the first ground member 15, but the degree of freedom in the shape and size of the first ground member 15 may be limited by surrounding members such as the second ground member 25. In this way, there may be a situation where the shape and size of the first ground member 15 cannot be freely adjusted in order to adjust the directivity of the first antenna 11.

[0044] However, since the antenna device 1 of the present embodiment includes the second filter 32 that allows the signal of the first frequency band resonating in the first antenna 11 to pass through, the region that functions as a ground portion for the signal of the first frequency band can be expanded beyond the region of the first ground member 15. That is, by using the second filter 32, at least a part of the signal of the first frequency band can be transmitted to the second ground member 25, so for the signal of the first frequency band, the region near the second filter 32 in the second ground member 25 functions as a ground portion.

[0045] In addition, when a part of the signal of the first frequency band passes through the first filter 31, at least a part of the signal of the first frequency band resonating in the first antenna 11 can be transmitted to the second ground member 25 via the first filter 31. Therefore, for the signal of the first frequency band, the region near the first filter 31 in the second ground member 25 also functions as a ground portion. Here, the size of the region in the second ground member 25 that functions as a ground portion for the signal of the first frequency band varies according to the attenuation degree of the signal of the first frequency band in the first filter 31. Therefore, regarding the size of the region in the second ground member 25 that functions as a ground portion for the signal of the first frequency band, the region near the second filter 32 is larger than the region near the first filter 31. In this way, according to the attenuation degrees of the signal of the first frequency band by the first filter 31 and the second filter 32, the size of the region that functions as a ground portion for the signal of the first frequency band changes.

[0046] As described above, according to the configurations of the first filter 31 and the second filter 32, and the frequency characteristics, the region of the second grounding member 25 that functions as a ground portion for the signal in the first frequency band resonating in the first antenna 11 changes. Thus, by adjusting the configurations and frequency characteristics of the first filter 31 and the second filter 32, it is possible to adjust the shape and size of the region that functions as a ground portion for the signal in the first frequency band. Thereby, the directivity of the first antenna 11 can be adjusted.

[0047] In addition, in the present embodiment, since the distances of the first filter 31 and the second filter 32 from the first antenna 11 are each less than 1 / 2 of the wavelength corresponding to the first frequency band, the above-described effect is more significant.

[0048] In addition, the directivity of the first antenna 11 has been described above, but regarding the directivity of the second antenna 21 as well as that of the first antenna 11, it can be adjusted by adjusting the configurations and frequency characteristics of the first filter 31 and the second filter 32. For example, it can be that the second filter 32 attenuates the signal in the second frequency band, and the first filter 31 has less attenuation of the signal in the second frequency band compared to the second filter 32. For example, it can be that in the first filter 31, the attenuation of the signal in the second frequency band is 3 dB or more less than that in the second filter 32. In the first filter 31, by allowing the signal in the second frequency band to pass through, for the signal in the second frequency band, the region near the first filter 31 in the first grounding member 15 also functions as a ground portion. When a part of the signal in the second frequency band passes through the second filter 32, at least a part of the signal in the second frequency band can be transmitted from the second grounding member 25 to the first grounding member 15 via the second filter 32. Therefore, for the signal in the second frequency band, the region near the second filter 32 in the first grounding member 15 also functions as a ground portion.

[0049] As described above, according to the configurations of the first filter 31 and the second filter 32, and the frequency characteristics, the region of the first grounding member 15 that functions as a ground portion for the signal in the second frequency band resonating in the second antenna 21 changes. Thus, by adjusting the configurations and frequency characteristics of the first filter 31 and the second filter 32, it is possible to adjust the shape and size of the region that functions as a ground portion for the signal in the second frequency band. Thereby, the directivity of the second antenna 21 can be adjusted.

[0050] In addition, in the present embodiment, since the distances of the first filter 31 and the second filter 32 from the second antenna 21 are each less than 1 / 2 of the wavelength corresponding to the second frequency band, the above-described effect is more significant.

[0051] In addition, although the antenna device 1 of the present embodiment includes two filters, i.e., a first filter 31 and a second filter 32, the antenna device 1 may include three or more filters that are arranged at different positions and connect the first ground component 15 and the second ground component 25. Thereby, the directivities of the first antenna 11 and the second antenna 21 can be adjusted more precisely.

[0052] (Embodiment 2)

[0053] The antenna device of Embodiment 2 will be described. The antenna device of the present embodiment is mainly different from the antenna device 1 of Embodiment 1 in the number of antennas and the shape of the ground component. Hereinafter, the antenna device of the present embodiment will be described centering on the differences from the antenna device 1 of Embodiment 1.

[0054] [2-1. Structure]

[0055] First, Figure 3 the structure of the antenna device of the present embodiment will be described. Figure 3 is a schematic plan view showing the structure of the antenna device 101 of the present embodiment. The antenna device 101, like the antenna device 1 of Embodiment 1, transmits and receives signals in a first frequency band and a second frequency band different from the first frequency band. As Figure 3 shown, the antenna device 101 includes a first ground component 115, two first antennas 111 and 112, a second ground component 125, two second antennas 121 and 122, two first filters 131 and 133, and two second filters 132 and 134. In the present embodiment, the antenna device 101 further includes a substrate 150.

[0056] The first ground component 115 is a conductive component connected to a ground portion. In the present embodiment, the first ground component 115 has an annular shape and is arranged in a region around the second ground component 125 on the substrate 150.

[0057] The second ground component 125 is arranged adjacent to the first ground component 115 with a gap 160 therebetween, and is a conductive component connected to a ground portion different from the first ground component 115. The shape of the second ground component 125 is not particularly limited. In the present embodiment, the second ground component 125 has a rectangular shape and is arranged in a region surrounded by the region where the first ground component 115 is arranged on the substrate 150. The gap 160 is a portion that electrically insulates the first ground component 115 and the second ground component 125. In the present embodiment, the gap 160 is a void having a width of about 1 mm.

[0058] The first antennas 111 and 112 are connected to the first grounding member 115 and are antennas that resonate in the first frequency band. In the present embodiment, the first antennas 111 and 112 have the same structure as the first antenna 11 of Embodiment 1. As Figure 3 shown, the first antennas 111 and 112 are respectively disposed at left and right positions with respect to the second grounding member 125.

[0059] The second antennas 121 and 122 are connected to the second grounding member 125 and are antennas that resonate in a second frequency band different from the first frequency band. In the present embodiment, the second antennas 121 and 122 have the same structure as the second antenna 21 of Embodiment 1.

[0060] The substrate 150 is an electrically insulating plate-like member that serves as the base of the antenna device 101. On one main surface of the substrate 150, the first antennas 111 and 112, the first grounding member 115, the second antennas 121 and 122, the second grounding member 125, the first filters 131 and 133, and the second filters 132 and 134 are disposed.

[0061] The first filters 131 and 133 and the second filters 132 and 134 are frequency filters that connect the first grounding member 115 and the second grounding member 125, respectively. The first filters 131 and 133 have the same structure as the first filter 31 of Embodiment 1 and attenuate signals in the first frequency band. The second filters 132 and 134 have the same structure as the second filter 32 of Embodiment 1 and, compared with the first filters 131 and 133, have less attenuation of signals in the first frequency band and allow signals in the first frequency band to pass through. The first filter 131 and the second filter 132 are disposed between the first antenna 111 and the second grounding member 125. The first filter 133 and the second filter 134 are disposed between the first antenna 112 and the second grounding member 125.

[0062] In the present embodiment, the first filters 131 and 133 and the second filters 132 and 134 are respectively disposed at positions where the distance from one of the two first antennas 111 and 112 is less than or equal to 1 / 2 of the wavelength corresponding to the first frequency band. In addition, the first filters 131 and 133 and the second filters 132 and 134 are respectively disposed at positions where the distance from one of the two second antennas 121 and 122 is less than or equal to 1 / 2 of the wavelength corresponding to the second frequency band.

[0063] [2-2. Function and Effect]

[0064] Next, the operation and effects of the antenna device 101 of the present embodiment will be described. Similar to the antenna device 1 of Embodiment 1, the antenna device 101 of the present embodiment includes second filters 132 and 134 that connect the first ground member 115 and the second ground member 125 and allow signals in the first frequency band to pass through. Thus, by means of the second filters 132 and 134, at least a part of the signals in the first frequency band can be transmitted to the second ground member 125. Therefore, for the signals in the first frequency band that resonate in each of the first antennas, the region near the second filters 132 and 134 in the second ground member 125 functions as a ground portion.

[0065] In addition, when a part of the signals in the first frequency band that resonate in the first antennas 111 and 112 passes through the first filters 131 and 133, for the signals in the first frequency band, the region near the first filters 131 and 133 in the second ground member 125 also functions as a ground portion.

[0066] As described above, according to the configuration and frequency characteristics of the first filters 131 and 133 and the second filters 132 and 134, the region of the second ground member 125 that functions as a ground portion for the signals in the first frequency band that resonate in the first antennas 111 and 112 changes. Therefore, by adjusting the configuration and frequency characteristics of the first filters 131 and 133 and the second filters 132 and 134, it is possible to adjust the shape and size of the region that functions as a ground portion for the signals in the first frequency band. Thereby, the directivity of the first antennas 111 and 112 can be adjusted.

[0067] In addition, although the directivity of the first antennas 111 and 112 has been described above, regarding the directivity of the second antennas 121 and 122, it is also the same as that of the first antennas 111 and 112, and can be adjusted by adjusting the configuration and frequency characteristics of the first filters 131 and 133 and the second filters 132 and 134.

[0068] (Embodiment 3)

[0069] The antenna device of Embodiment 3 will be described. The antenna device of the present embodiment is mainly different from the antenna device 101 of Embodiment 2 in the structure of the gap between the first ground member and the second ground member. Hereinafter, the antenna device of the present embodiment will be described centering on the differences from the antenna device 101 of Embodiment 2.

[0070] [3-1. Structure]

[0071] First, use Figure 4 to describe the structure of the antenna device of the present embodiment. Figure 4It is a schematic plan view showing the structure of the antenna device 101a of the present embodiment. The antenna device 101a, like the antenna device 101 of the second embodiment, transmits and receives signals in a first frequency band and signals in a second frequency band different from the first frequency band. As Figure 4 shown, the antenna device 101a includes a first ground component 115, first antennas 111 and 112, a second ground component 125, second antennas 121 and 122, first filters 131 and 133, second filters 132 and 134, and a substrate 150. The antenna device 101a of the present embodiment further includes conduction components 171 to 174. In the present embodiment, the second ground component 125 is disposed beside the first ground component 115 with gaps 161 to 164 and conduction components 171 to 174 therebetween.

[0072] The conduction components 171 to 174 are conductive components that conduct the first ground component 115 and the second ground component 125. Thereby, the conduction components 171 to 174 cut off the gaps between the first ground component 115 and the second ground component 125. The distances from each of the conduction components 171 to 174 to the first antenna 111 and the distances from each of the conduction components 171 to 174 to the first antenna 112 are longer than 1 / 2 of the wavelength corresponding to the first frequency band. Thereby, the characteristics of the first antennas 111 and 112 do not substantially change depending on the presence or absence of the conduction components 171 to 174. That is, the influence of the conduction components 171 to 174 on the first antennas 111 and 112 can be ignored. In addition, the distances from each of the conduction components 171 to 174 to the second antenna 121 and the distances from each of the conduction components 171 to 174 to the second antenna 122 are longer than 1 / 2 of the wavelength corresponding to the second frequency band. Thereby, the characteristics of the second antennas 121 and 122 do not substantially change depending on the presence or absence of the conduction components 171 to 174. That is, the influence of the conduction components 171 to 174 on the second antennas 121 and 122 can be ignored. The width of the conduction components 171 to 174 is not particularly limited, and in the present embodiment, it is about 1 / 200 or less of each wavelength corresponding to the first frequency band and the second frequency band.

[0073] [3-2. Function and Effect]

[0074] Next, the operation and effects of the antenna device 101a of the present embodiment will be described in comparison with the antenna device 101 of Embodiment 2. In the antenna device 101 of Embodiment 2, the first grounding member 115 has an annular inner peripheral edge. Here, generally in an antenna, current easily flows at the edge of the conductive member constituting the antenna, so the current will flow along its inner peripheral edge. Therefore, this inner peripheral edge functions as an antenna and generates unwanted electromagnetic waves. Similarly, the outer peripheral edge of the second grounding member 125 also functions as an antenna and generates unwanted electromagnetic waves. In contrast, in the antenna device 101a of the present embodiment, the gaps between the first grounding member 115 and the second grounding member 125 are truncated into four gaps 161 to 164 by the conduction members 171 to 174. Consequently, the inner peripheral edge of the first grounding member 115 and the outer peripheral edge of the second grounding member 125 are also truncated. Therefore, it is possible to suppress the generation of unwanted electromagnetic waves at the inner peripheral edge of the first grounding member 115 and the outer peripheral edge of the second grounding member 125.

[0075] In addition, in the present embodiment, the antenna device 101a includes four conduction members 171 to 174, but the number of conduction members is not limited to four, and any number of one or more is acceptable.

[0076] (Embodiment 4)

[0077] The antenna device of Embodiment 4 will be described. The antenna device of the present embodiment mainly differs from the antenna device 1 of Embodiment 1 in that it further includes a conductive member that can affect the directivity of each antenna. Hereinafter, the antenna device of the present embodiment will be described centering on the differences from the antenna device 1 of Embodiment 1.

[0078] [4 - 1. Structure]

[0079] First, Figure 5 the structure of the antenna device of the present embodiment will be described. Figure 5 is a schematic plan view showing the structure of the antenna device 201 of the present embodiment. As Figure 5 shown, the antenna device 201 includes a first grounding member 15, a first antenna 11, a second grounding member 25, a second antenna 21, a first filter 231, a second filter 232, a substrate 250, and a peripheral circuit 280.

[0080] The substrate 250 is an electrically insulating plate - like member that serves as the base of the antenna device 201. Similar to the substrate 50 of Embodiment 1, on one main surface of the substrate 250, the first antenna 11, the first grounding member 15, the second antenna 21, the second grounding member 25, the first filter 231, and the second filter 232 are arranged. In the present embodiment, on one main surface of the substrate 250, a peripheral circuit 280 is also arranged.

[0081] The peripheral circuit 280 is a circuit disposed on the substrate 250 and is an example of a conductive component included in the antenna device 201. In the present embodiment, the peripheral circuit 280 is disposed at a position adjacent to the first ground component 15 and on the opposite side of the second ground component 25 with respect to the first antenna 11. In other words, the first antenna 11 is disposed between the peripheral circuit 280 and the second ground component 25. The structure of the peripheral circuit 280 is not particularly limited. For example, the peripheral circuit 280 may be a circuit that generates or extracts signals supplied to the first antenna 11 and the second antenna 21, or may be a circuit that extracts signals of a specified frequency from the signals received by the first antenna 11 and the second antenna 21, etc.

[0082] The first filter 231 is the same as the first filter 31 of Embodiment 1 and is a frequency filter that connects the first ground component 15 and the second ground component 25 and attenuates signals in the first frequency band. In the present embodiment, the first filter 231 attenuates signals in the first frequency band more than signals in the second frequency band. The first filter 231 allows signals in the second frequency band to pass through.

[0083] The second filter 232 is the same as the second filter 32 of Embodiment 1 and is a frequency filter that connects the first ground component 15 and the second ground component 25 and attenuates signals in the first frequency band less than the first filter 231. In the present embodiment, the second filter 232 attenuates signals in the second frequency band more than signals in the first frequency band. The second filter 232 allows signals in the first frequency band to pass through.

[0084] [4-2. Function and Effect]

[0085] Next, the function and effect of the antenna device 201 of the present embodiment will be described. As described above, the antenna device 201 of the present embodiment includes the peripheral circuit 280. Since the peripheral circuit 280 includes many conductive components such as ground wirings, it is possible to affect the directivity of each antenna included in the antenna device 201. Specifically, the directivity of the antenna will be biased toward the direction opposite to the direction from the antenna toward the conductive component. In Figure 5 the example shown, the peripheral circuit 280 has the greatest influence on the directivity of the first antenna 11 disposed at a position adjacent to the peripheral circuit 280. Specifically, by disposing the peripheral circuit 280, the directivity of the first antenna 11 is biased toward the direction opposite to the direction from the first antenna 11 toward the peripheral circuit 280 (that is, the direction from the first antenna 11 toward the second ground component 25).

[0086] However, in the present embodiment, at least the second filter 232 allows the signal of the first band to pass therethrough. Thus, for the signal of the first band resonating in the first antenna 11, the vicinity of the second filter 232 in the second ground member 25 functions as a ground portion. Therefore, an effect can be obtained as if the first ground member 15 is expanded to the region where the second ground member 25 is disposed. Accordingly, the directivity of the first antenna 11 can be suppressed from being biased toward the second ground member 25. Further, the antenna device 201 may further include a frequency filter that connects the first ground member 15 and the second ground member 25 and allows the signal of the first band to pass therethrough, in addition to the first filter 231 and the second filter 232. Thereby, the influence of the peripheral circuit 280 on the directivity of the first antenna 11 can be further suppressed.

[0087] (Embodiment 5)

[0088] The antenna device according to Embodiment 5 will be described. The antenna device of the present embodiment, like the antenna device 201 of Embodiment 4, includes a conductive member that can affect the directivity of each antenna. The structure of the conductive member of the antenna device of the present embodiment is different from that of the antenna device 201 of Embodiment 4. Hereinafter, the antenna device of the present embodiment will be described centering on the differences from the antenna device 201 of Embodiment 4.

[0089] [5-1. Structure]

[0090] First, Figure 6 and Figure 7 will be used to describe the structure of the antenna device of the present embodiment. Figure 6 and Figure 7 are a schematic plan view and a side view showing the structure of the antenna device 201a of the present embodiment, respectively. As Figure 6 and Figure 7 show, the antenna device 201a of the present embodiment includes a first ground member 15, a first antenna 11, a second ground member 25, a second antenna 21, a first filter 231a, a second filter 232a, a substrate 250a, a frame 280a, and a support 285.

[0091] The substrate 250a is an electrically insulating plate-like member that serves as a base of the antenna device 201a. Similar to the substrate 250 of Embodiment 4, on one main surface of the substrate 250a, the first antenna 11, the first ground member 15, the second antenna 21, the second ground member 25, the first filter 231a, and the second filter 232a are disposed. In the present embodiment, as Figure 7 shows, the substrate 250a is disposed on the frame 280a via the support 285. Alternatively, the substrate 250a may be directly disposed on the frame 280a without the support 285.

[0092] The frame 280a is a structure for fixing the substrate 250a and is an example of a conductive component included in the antenna device 201a. The frame 280a includes a wall portion 281 and a pedestal portion 282. The frame 280a is formed of a conductive material such as aluminum or magnesium, for example.

[0093] The wall portion 281 is a plate-like portion erected on the pedestal portion 282. As Figure 7 shown, the length of the wall portion 281 from the pedestal portion 282 is longer than the distance from the pedestal portion 282 to the first antenna 11 and the second antenna 21. In the present embodiment, the wall portion 281 is disposed adjacent to the first grounding member 15 and on the opposite side of the second grounding member 25 with respect to the first antenna 11. In other words, the first antenna 11 is disposed between the wall portion 281 and the second grounding member 25.

[0094] The pedestal portion 282 is a plate-like portion on which the substrate 250a is disposed. In the present embodiment, the pedestal portion 282 has a mounting surface whose size is larger than the main surface of the substrate 250a, and the substrate 250a is disposed on this mounting surface.

[0095] The support member 285 is a member disposed between the frame 280a and the substrate 250a. The support member 285 is connected to the frame 280a and the substrate 250a. The support member 285 can be connected to the frame 280a and the substrate 250a by an adhesive or the like, or can be connected by screws or the like. The antenna device 201a of the present embodiment includes four cylindrical support members 285, which are respectively disposed at the four corners of the substrate 250a. In addition, the frame 280a is connected to one of the two circular bottom surfaces of the cylindrical support member 285, and the substrate 250a is connected to the other.

[0096] The first filter 231a is the same as the first filter 231 of Embodiment 4 and is a frequency filter that connects the first grounding member 15 and the second grounding member 25 and attenuates the signal of the first frequency band. In the present embodiment, the first filter 231a attenuates the signal of the first frequency band more than the signal of the second frequency band. The first filter 231a can attenuate the signal of the second frequency band or can not attenuate it.

[0097] The second filter 232a is the same as the second filter 232 of Embodiment 4 and is a frequency filter that connects the first grounding member 15 and the second grounding member 25 and attenuates the signal of the first frequency band less than the first filter 231a. In the present embodiment, the second filter 232a can attenuate the signal of the second frequency band or can not attenuate it.

[0098] [5-2. Function and Effect]

[0099] Next, the operation and effects of the antenna device 201a of the present embodiment will be described. The antenna device 201a of the present embodiment includes the frame 280a as described above. Since the frame 280a is a conductive component, it can affect the directivity of each antenna included in the antenna device 201a. Specifically, the directivity of the antenna will be biased toward the direction opposite to the direction from the antenna toward the conductive component. In Figure 6 and Figure 7 In the example shown, the frame 280a has the greatest influence on the directivity of the first antenna 11 disposed adjacent to the wall portion 281. Specifically, by disposing the frame 280a, the directivity of the first antenna 11 will be biased toward the direction opposite to the direction from the first antenna 11 toward the frame 280a (that is, the direction from the first antenna 11 toward the second ground component 25).

[0100] However, in the present embodiment, at least the second filter 232a allows the signal of the first band to pass through. Thus, for the signal of the first band resonating in the first antenna 11, the vicinity of the second filter 232a in the second ground component 25 functions as a ground portion. Therefore, an effect is obtained as if the first ground component 15 is expanded to the region where the second ground component 25 is disposed. Consequently, it is possible to suppress the directivity of the first antenna 11 from being biased toward the direction toward the second ground component 25. In addition, the antenna device 201a may further include a frequency filter that connects the first ground component 15 and the second ground component 25 and allows the signal of the first band to pass through, in addition to the first filter 231a and the second filter 232a. Thereby, it is possible to further suppress the influence of the frame 280a on the directivity of the first antenna 11.

[0101] (Embodiment 6)

[0102] The antenna device of Embodiment 6 will be described. The antenna device of the present embodiment is mainly different from the antenna device 101 of Embodiment 2 in the number and arrangement of the antennas and filters respectively. Hereinafter, for the antenna device of the present embodiment, the differences from the antenna device 101 of Embodiment 2 will be mainly described.

[0103] [6-1. Structure]

[0104] First, Figures 8 - 10 is used to describe the structure of the antenna device of the present embodiment. Figure 8 is a schematic perspective view showing the structure of the antenna device 301 of the present embodiment. Figure 9 is a schematic plan view showing the structure of the first layer portion 302a of the antenna device 301 of the present embodiment. In Figure 9 a plan view of the main surface of the substrate 350a included in the first layer portion 302a is shown in a plan view. Figure 10is a schematic plan view showing the structure of the second layer portion 302b of the antenna device 301 of the present embodiment. In Figure 10 it shows a plan view of the main surface of the substrate 350b included in the second layer portion 302b in a plan view.

[0105] As Figure 8 shown, the antenna device 301 of the present embodiment includes a first layer portion 302a and a second layer portion 302b disposed apart from the first layer portion 302a. In the present embodiment, the second layer portion 302b is disposed such that the main surface of the substrate 350b included in the second layer portion 302b is parallel to the main surface of the substrate 350a included in the first layer portion 302a. In addition, although not shown, between the first layer portion 302a and the second layer portion 302b, an electrically insulating spacer or the like for fixing the relative positions of the first layer portion 302a and the second layer portion 302b may be disposed.

[0106] As Figure 9 shown, the first layer portion 302a includes a first ground component 315, first antennas 311 to 314, a second ground component 329a, second antennas 321 to 325, first filters 331a, 333a, 334a, and 335a, second filters 331b, 333b, 334b, and 335b, a third filter 332a, a fourth filter 332b, and a substrate 350a.

[0107] The first ground component 315 is a conductive component connected to the ground portion. In the present embodiment, the first ground component 315 has an annular shape and is disposed in the peripheral region of the second ground component 329a on the substrate 350a. The shapes of the outer peripheral edge and the inner peripheral edge of the first ground component 315 are a quadrilateral and a pentagon, respectively.

[0108] The first antennas 311 to 314 are respectively connected to the first ground component 315 and are antennas that resonate in the first frequency band. In the present embodiment, the first antennas 311 to 314 have the same structure as the first antenna 11 of Embodiment 1. As Figure 8 and Figure 9 shown, the first antennas 311 to 314 are respectively disposed near the vertices of the quadrilateral outer peripheral edge of the first ground component 315. The distance from each first antenna to the nearest other first antenna is about 1 / 2 of the wavelength corresponding to the first frequency band. That is, the distance between the first antenna 311 and the first antenna 312, the distance between the first antenna 312 and the first antenna 313, the distance between the first antenna 313 and the first antenna 314, and the distance between the first antenna 314 and the first antenna 311 are about 1 / 2 of the wavelength corresponding to the first frequency band.

[0109] The second grounding member 329a is disposed at a position adjacent to the first grounding member 315 with a gap 360 therebetween, and is a conductive member connected to a grounding portion different from the first grounding member 315. In the present embodiment, the shape of the second grounding member 329a is pentagonal, and it is disposed in a region surrounded by the region where the first grounding member 315 is disposed on the substrate 350a. The gap 360 is the region between the first grounding member 315 and the second grounding member 329a. In the present embodiment, the gap 360 has a width of about 1 mm.

[0110] The second antennas 321 to 325 are respectively connected to the second grounding member 329a, and are antennas that resonate in the second frequency band. In the present embodiment, the second antennas 321 to 325 have the same structure as the second antenna 21 of Embodiment 1. As Figure 8 and Figure 9 shown, the second antennas 321 to 325 are respectively disposed near the respective vertices of the pentagonal second grounding member 329a. The distance from each second antenna to the nearest other second antenna is about 1 / 2 of the wavelength corresponding to the second frequency band. That is, the distance between the second antenna 321 and the second antenna 322, the distance between the second antenna 322 and the second antenna 323, the distance between the second antenna 323 and the second antenna 324, the distance between the second antenna 324 and the second antenna 325, and the distance between the second antenna 325 and the second antenna 321 are about 1 / 2 of the wavelength corresponding to the second frequency band.

[0111] The substrate 350a is an electrically insulating plate-like member that serves as the base of the first layer portion 302a of the antenna device 301. On one main surface of the substrate 350a, the first antennas 311 to 314, the first grounding member 315, the second antennas 321 to 325, the second grounding member 329a, the first filters 331a, 333a, 334a, and 335a, the second filters 331b, 333b, 334b, and 335b, the third filter 332a, and the fourth filter 332b are disposed.

[0112] The first filters 331a, 333a, 334a, and 335a, the second filters 331b, 333b, 334b, and 335b, the third filter 332a, and the fourth filter 332b are frequency filters that connect the first grounding member 315 and the second grounding member 329a, respectively. The first filters 331a, 333a, 334a, and 335a have the same structure as the first filter 31 of Embodiment 1 and attenuate the signals in the first frequency band. The second filters 331b, 333b, 334b, and 335b have the same structure as the second filter 32 of Embodiment 1, attenuate the signals in the first frequency band less than the first filters 331a, 333a, 334a, and 335a, and pass the signals in the first frequency band. In the present embodiment, the third filter 332a attenuates the signals in the second frequency band. The fourth filter 332b attenuates the signals in the second frequency band less than the third filter 332a and passes the signals in the second frequency band.

[0113] In the present embodiment, each filter disposed in the first layer portion 302a is disposed at a position where the distance from any one of the four first antennas 311 to 314 is less than or equal to 1 / 2 of the wavelength corresponding to the first frequency band. In addition, each filter is disposed at a position where the distance from any one of the five second antennas 321 to 325 is less than or equal to 1 / 2 of the wavelength corresponding to the second frequency band.

[0114] As Figure 8 and Figure 10 shown, the second layer portion 302b includes a third grounding member 329b, third antennas 326 to 328, and a substrate 350b.

[0115] The third grounding member 329b is a conductive member connected to a grounding portion different from the first grounding member 315. The third grounding member 329b can be connected to, for example, the same grounding portion as the second grounding member 329a. In the present embodiment, the shape of the third grounding member 329b is hexagonal and is disposed on the substrate 350b. The third grounding member 329b is disposed on a plane different from that of the second grounding member 329a. In the present embodiment, the third grounding member 329b is disposed along the second grounding member 329a.

[0116] The third antennas 326 to 328 are respectively connected to the third ground component 329b and are antennas that resonate in the second frequency band. In the present embodiment, the third antennas 326 to 328 have the same structure as the second antenna 21 of Embodiment 1. The third antennas 326 to 328 are respectively arranged such that the distance to other third antennas is approximately 1 / 2 of the wavelength corresponding to the second frequency band. That is, the distance between the third antenna 326 and the third antenna 327, the distance between the third antenna 327 and the third antenna 328, and the distance between the third antenna 328 and the third antenna 326 are approximately 1 / 2 of the wavelength corresponding to the second frequency band. In addition, the distances between the third antenna 326 and the second antennas 321 and 322 of the first layer portion 302a, between the third antenna 327 and the second antennas 322 and 323 of the first layer portion 302a, and between the third antenna 328 and the second antennas 324 and 325 of the first layer portion 302a are also approximately 1 / 2 of the wavelength corresponding to the second frequency band.

[0117] The substrate 350b is an electrically insulating plate-like component that serves as the base of the second layer portion 302b of the antenna device 301. On one main surface of the substrate 350b, the third antennas 326 to 328 and the third ground component 329b are arranged.

[0118] [6 - 2. Function and Effect]

[0119] Next, the function and effect of the antenna device 301 of the present embodiment will be described. The antenna device 301 of the present embodiment, like the antenna device 1 of Embodiment 1, includes second filters 331b, 333b, 334b, and 335b that connect the first ground component 315 and the second ground component 329a and allow the signals in the first frequency band to pass through. Thus, by using each second filter, at least a part of the signals in the first frequency band can be transmitted to the second ground component 329a. Therefore, for the signals in the first frequency band that resonate in each first antenna, the region near each second filter in the second ground component 329a functions as a ground portion.

[0120] In addition, when a part of the signals in the first frequency band that resonate in each first antenna passes through each first filter, the region near each first filter in the second ground component 329a also functions as a ground portion for the signals in the first frequency band that resonate in each first antenna.

[0121] As described above, according to the configuration and frequency characteristics of each filter in the first-layer part 302a, the region of the second grounding member 329a that functions as a grounding part for the signals in the first frequency band resonating in each first antenna changes. Therefore, by adjusting the configuration and frequency characteristics of each filter, it is possible to adjust the shape and size of the region that functions as a grounding part for the signals in the first frequency band. Thus, the directivity of each first antenna can be adjusted. In particular, in the antenna device 301 such as in the present embodiment that includes a second-layer part 302b, the third grounding member 329b and the like included in the second-layer part 302b can affect the directivity of each first antenna. In such an antenna device 301, it is also possible to adjust the directivity of each first antenna by adjusting the configuration and frequency characteristics of each filter to suppress this influence.

[0122] In addition, although the directivity of each first antenna has been described above, regarding the directivity of each second antenna included in the first-layer part 302a, similar to each first antenna, it can be adjusted by adjusting the configuration and frequency characteristics of each filter. In particular, in the antenna device 301 of the present embodiment, the second-layer part 302b has a greater influence on the directivity of each second antenna arranged in the first-layer part 302a. In such an antenna device 301, it is also possible to adjust the directivity of each second antenna by adjusting the configuration and frequency characteristics of each filter to suppress this influence.

[0123] In addition, since the antenna device 301 includes four first antennas 311 to 314 that resonate in the first frequency band, it can be applied to 4×4 MIMO (Multiple-Input and Multiple-Output) for the signals in the first frequency band. In addition, since the antenna device 301 includes eight antennas (second antennas 321 to 325 and third antennas 326 to 328) that resonate in the second frequency band, it can be applied to 8×8 MIMO for the signals in the second frequency band.

[0124] [6-3. Variation Example]

[0125] Next, an antenna device of a variation example of the present embodiment will be described. In the antenna device 301 of Embodiment 6, the shape of the second grounding member 329a is a pentagon, but the shape of the second grounding member 329a is not limited thereto. Hereinafter, as the antenna device of this variation example, an example in which the shape of the second grounding member 329a is not a pentagon will be described.

[0126] In the antenna device of this variation example, the shape of the second grounding member 329a is a quadrilateral having the same number of sides as the number of first antennas.

[0127] In addition, in the antenna device of this modification example, the shape of the inner peripheral edge of the first ground member 315 is also a quadrilateral, similar to the shape of the second ground member 329a.

[0128] In this case, each first antenna can be arranged at a position facing the vicinity of the center of each side of the inner peripheral edge of the quadrilateral of the first ground member 315.

[0129] In addition, in this modification example, the shape of the gap 360 can also be different from that of the antenna device 301 of the sixth embodiment. Hereinafter, Figure 11 the gap 360 of the antenna device of this modification example will be described. Figure 11 is a schematic plan view showing the structure of the gap 360 of the antenna device of this modification example. In Figure 11 only one side of the quadrilateral gap 360 is shown.

[0130] As Figure 11 shown, the antenna device of this modification example is provided with a conduction member 370 in the same manner as the antenna device 101a of the third embodiment. In this modification example, the four conduction members 370 are respectively arranged at positions corresponding to the four vertices of the quadrilateral second ground member 329a. That is, at each vertex of the quadrilateral gap 360, the first ground member 315 and the second ground member 329a are conducted through the conduction member 370. Thus, in the antenna device of this modification example, the same effect as that of the antenna device 101a of the third embodiment is also achieved.

[0131] In addition, in the case where the first ground member 315 and the second ground member 329a are conducted through the conduction member 370 as in the antenna device of this modification example, the antenna device may not be provided with the first filter and the second filter.

[0132] In addition, in this modification example, as Figure 11 shown, the first ground member 315 has a plurality of first convex portions 315c protruding toward the second ground member 329a on the inner peripheral edge. In Figure 11 the example shown, the plurality of first convex portions 315c are arranged at equal intervals and have the same length. In addition, the second ground member 329a has a plurality of second convex portions 329ac protruding toward the first ground member 315 on the outer peripheral edge. In Figure 11 the example shown, the plurality of second convex portions 329ac are arranged at equal intervals and have the same length. That is, the shapes of the inner peripheral edge of the first ground member 315 and the outer peripheral edge of the second ground member 329a are each in a comb shape.

[0133] The plurality of first convex portions 315c and the plurality of second convex portions 329ac are arranged offset from each other. In other words, one second convex portion 329ac is arranged between two adjacent first convex portions 315c, and one first convex portion 315c is arranged between two adjacent second convex portions 329ac. By using the plurality of first convex portions 315c of the first grounding member 315 and the plurality of second convex portions 329ac of the second grounding member 329a, a part of the signal in the first frequency band can be transmitted from the first grounding member 315 to the second grounding member 329a, and a part of the signal in the second frequency band can be transmitted from the second grounding member 329a to the first grounding member 315. Therefore, by adjusting the shapes and sizes of the plurality of first convex portions 315c and the plurality of second convex portions 329ac, for the signal in the first frequency band, the region that functions as a grounding portion in the second grounding member 329a can be adjusted, and for the signal in the second frequency band, the region that functions as a grounding portion in the first grounding member 315 can be adjusted. Thus, the directivity of each antenna can be adjusted.

[0134] As described above, the shape of the inner peripheral edge of the first grounding member 315 and the shape of the second grounding member 329a are not limited to a pentagon, and may be a polygon other than a pentagon, or a shape other than a polygon such as an ellipse. In addition, the shape of the inner peripheral edge of the first grounding member 315 and the shape of the second grounding member 329a may be a polygon and have the same number of vertices (or sides) as the first antenna.

[0135] In addition, the antenna device of this modification includes four conduction members 370, but the number of conduction members 370 may be 1 or more.

[0136] In addition, the structure of the antenna device 301 in Embodiment 6 and the structure of the antenna device of this modification may be appropriately combined. For example, the antenna device 301 in Embodiment 6 may also include a conduction member 370. In addition, the first grounding member 315 of the antenna device 301 in Embodiment 6 may also have a plurality of first convex portions 315c on its inner peripheral edge, and the second grounding member 329a may also have a plurality of second convex portions 329ac on its outer peripheral edge. In addition, the first grounding member 315 of the antenna device 301 in Embodiment 6 may not include each filter. In addition, the first grounding member 315 of this modification may not include a plurality of first convex portions 315c, and the second grounding member 329a may not include a plurality of second convex portions 329ac. In addition, the antenna device of this modification may not include a conduction member 370, or may include a filter similar to each filter in Embodiment 6.

[0137] (Modification example, etc.)

[0138] As described above, the antenna device of the present invention has been described based on each embodiment, but the present invention is not limited to the above-described embodiments. As long as the gist of the present invention is not deviated from, forms obtained by various modifications that can be conceived by those skilled in the art for the above-described embodiments can also be included in the scope of the present invention.

[0139] For example, in the above-described embodiments, the first frequency band is a lower frequency band than the second frequency band, but the first frequency band may also be a higher frequency band than the second frequency band.

[0140] In addition, in the above-described embodiments, a copper film is used as the first ground component and the second ground component, but a conductive component other than the copper film may also be used. As the first ground component and the second ground component, for example, a metal plate made of copper or aluminum may also be used.

[0141] In addition, in the above-described embodiments, a metal plate is used as the first antenna and the second antenna, but a conductive component other than the metal plate may also be used. As the first antenna and the second antenna, for example, a conductive film such as a copper film formed on an insulating substrate may also be used.

[0142] In addition, in the above-described embodiments, the gaps between the first ground component and the second ground component are all voids, but the structure of the gaps is not particularly limited as long as the first ground component and the second ground component can be electrically insulated. For example, an insulating material may also be filled in the gaps.

[0143] In addition, in the above-described embodiments, the widths of the gaps between the first ground component and the second ground component are constant, but they may not be constant. For example, in the portions where the first filter and the second filter are arranged, the widths of the gaps may also be changed to match the sizes of the respective filters.

[0144] In addition, in the above-described embodiments, the shapes of the respective ground components may also be appropriately changed. For example, a slit-shaped insulating region (i.e., a region that does not constitute a ground component) may also be arranged inside each ground component. By arranging such an insulating region around each antenna, the directivity of each antenna can be adjusted.

[0145] In addition, forms and the like achieved by arbitrarily combining the constituent elements and functions of each embodiment within the scope of not departing from the gist of the present invention are also included in the present invention.

[0146] For example, the antenna devices of Embodiments 2, 3, and 6 may also include the peripheral circuit 280 of Embodiment 4 or the frame 280a of Embodiment 5.

[0147] Industrial Applicability

[0148] The antenna device of the present invention is an antenna device capable of transmitting and receiving signals in multiple frequency bands and adjusting the directivity of the antenna, and can be used, for example, in a wireless LAN router or the like.

[0149] Reference Numeral Explanation

[0150] 1, 101, 101a, 201, 201a, 301 Antenna device

[0151] 11, 111, 112, 311, 312, 313, 314 First antenna

[0152] 11a, 21a Main body part

[0153] 11b, 21b Power supply part

[0154] 11c, 21c Short - circuit part

[0155] 15, 115, 315 First grounding component

[0156] 21, 121, 122, 321, 322, 323, 324, 325 Second antenna

[0157] 25, 125, 329a Second grounding component

[0158] 31, 131, 133, 231, 231a, 331a, 333a, 334a First filter

[0159] 32, 132, 134, 232, 232a, 331b, 333b, 334b Second filter

[0160] 50, 150, 250, 250a, 350a, 350b Substrate

[0161] 60, 160, 161, 162, 163, 164, 360 Gap

[0162] 171, 172, 173, 174, 370 Conductive component

[0163] 280 Peripheral circuit

[0164] 280a Frame

[0165] 281 Wall part

[0166] 282 Base part

[0167] 285 Support

[0168] 302a First layer part

[0169] 302b Second layer part

[0170] 315c First convex part

[0171] 329ac Second convex part

[0172] 332a Third filter

[0173] 332b Fourth filter

[0174] 326, 327, 328 Third antenna

[0175] 329b Third grounding component

[0176] C1, C2, C3 Capacitors

[0177] L, L1, L2, L3 Inductors

Claims

1. An antenna device, characterized in that, it comprises: a first grounding component connected to a grounding portion; one or more first antennas connected to the first grounding component and resonating in a first frequency band; a second grounding component arranged adjacent to the first grounding component with a gap therebetween and connected to a grounding portion different from the first grounding component; one or more second antennas connected to the second grounding component and resonating in a second frequency band different from the first frequency band; one or more first filters connecting the first grounding component and the second grounding component to attenuate signals in the first frequency band; and one or more second filters connecting the first grounding component and the second grounding component at a position different from the one or more first filters to attenuate signals in the second frequency band, with less attenuation of signals in the first frequency band and greater attenuation of signals in the second frequency band compared to the one or more first filters.

2. The antenna device according to claim 1, characterized in that, the one or more first filters and the one or more second filters are respectively arranged at positions where the distance from a certain one of the one or more first antennas is less than or equal to 1 / 2 of the wavelength corresponding to the first frequency band.

3. The antenna device according to claim 1 or 2, characterized in that, the one or more first filters and the one or more second filters are respectively arranged at positions where the distance from a certain one of the one or more second antennas is less than or equal to 1 / 2 of the wavelength corresponding to the second frequency band.

4. The antenna device according to claim 1 or 2, characterized in that, in the one or more second filters, the attenuation of signals in the first frequency band is at least 3 dB less than that in the one or more first filters.

5. The antenna device according to claim 1 or 2, characterized in that, it further comprises a conductive component arranged adjacent to the first grounding component; a certain one of the one or more first antennas is arranged between the conductive component and the second grounding component.

6. The antenna device according to claim 1 or 2, characterized in that, the first grounding component has an annular shape and is arranged in an area around the second grounding component; the antenna device further comprises a conduction component for truncating the gap.

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