JP5187515B2 - ANTENNA DEVICE AND RADIO COMMUNICATION DEVICE - Google Patents

Description

  The present invention relates to an antenna device and a wireless communication device that are provided with countermeasures against static electricity.

In the wireless communication device, when the antenna comes into contact with the human body, static electricity may flow into the receiving circuit through the antenna and may destroy the receiving circuit. For this reason, for example, in the antenna device having a loop antenna disclosed in Patent Document 1 and Patent Document 2, a low-frequency cut capacitor is provided in front of a receiving circuit and a frequency variable circuit of the device, and an electrostatic discharge element is provided. A resistor is connected between the antenna and the ground so that the receiving circuit and the frequency variable circuit are protected from the static electricity that flows in, and the static electricity flows out to the ground.
However, for example, in the antenna device in which a narrow non-ground region is provided in the vicinity of the ground region and a frequency variable circuit and a radiation electrode are arranged in the non-ground region as in the monopole antenna disclosed in Patent Document 3, a receiving circuit However, the frequency variable circuit is not protected from static electricity.
For this reason, in such an antenna device, static electricity that enters the antenna flows into the frequency variable circuit and may have some influence on the frequency variable circuit.
Therefore, in such an antenna device, it is necessary to dispose a low-frequency cut capacitor in front of the frequency variable circuit and to connect the electrostatic discharge element from the radiation electrode to the ground region.

JP-A-4-227301 JP-A-8-330826 International Publication No. 2004/109850 Pamphlet International Publication No. 2006/080141 Pamphlet

The antenna device disclosed in Patent Document 3 has a configuration in which a frequency variable circuit and a radiation electrode are formed in a non-ground region. Even in such an antenna device, when there is one radiating electrode, that is, in a configuration in which transmission / reception is performed using one resonance frequency, a low-frequency cut capacitor is provided in front of the frequency variable circuit as in the loop antenna described above. In addition, it is possible to take measures against static electricity by connecting the electrostatic discharge element from the radiation electrode to the ground region.
However, for example, in a multiband antenna device in which a plurality of radiation electrodes having different resonance frequencies are formed in a non-ground region as in the antenna device disclosed in Patent Document 4, an electrostatic discharge element is provided for each of the plurality of radiation electrodes. And the respective electrostatic discharge devices need to be connected to the ground region.
In order to connect the plurality of radiation electrodes to the ground region through the electrostatic discharge element, it is necessary to bring all of the plurality of radiation electrodes close to the ground region side. If many radiating electrodes are brought close to the ground region or many electrostatic discharge elements are passed from the radiating electrode to the ground region, the antenna characteristics are deteriorated. In particular, when the open end of the radiation electrode is brought close to the ground region, the antenna characteristics are significantly deteriorated.
For this reason, in the multiband antenna device 1 in which a variable frequency circuit and a large number of radiation electrodes are formed in a narrow non-ground region, an antenna device that can take a reliable countermeasure against static electricity without causing deterioration of antenna characteristics. Was expected to appear.

  The present invention has been made to solve the above-described problems, and prevents inflow of the static electricity that has entered the radiation electrode into the frequency variable circuit and causes the static electricity to enter the ground region with almost no deterioration of the antenna characteristics. It is an object of the present invention to provide a multiband antenna device and a wireless communication apparatus that enable the outflow of a radio wave.

In order to solve the above problems, the invention of claim 1 is characterized in that a power supply electrode having one end connected to the power supply unit, a frequency variable circuit connected to the other end of the power supply electrode, An antenna device comprising a plurality of radiation electrodes connected to the other end of the feeding electrode via a frequency variable circuit and having the other end opened in a non-ground region of the substrate, wherein one end of the plurality of radiation electrodes And a variable frequency circuit, a low frequency cut capacitor is provided, and an electrostatic discharge element is interposed between the plurality of radiation electrodes, and one of the plurality of radiation electrodes is radiated. The electrode is configured to be connected to the ground region using an electrostatic discharge element separate from the electrostatic discharge element.
With this configuration, transmission and reception at a plurality of resonance frequencies can be performed by the feeding electrode, the frequency variable circuit, and the plurality of radiation electrodes. Each resonance frequency can be changed by the frequency variable circuit.
By the way, any of the plurality of radiation electrodes may come into contact with a human body or the like, and static electricity may enter the radiation electrode. Then, the static electricity tends to flow through the radiation electrode toward the frequency variable circuit side and flow into the frequency variable circuit.
However, in the antenna device according to the present invention, since the low frequency cut capacitor is provided between one end of the plurality of radiation electrodes and the frequency variable circuit, the static electricity that has entered the radiation electrode is reduced by this low frequency cut. It is blocked by the capacitor and no static electricity flows into the frequency variable circuit. In the antenna device of the present invention, the electrostatic discharge element is interposed between the plurality of radiation electrodes, and one of the plurality of radiation electrodes is separated by a separate electrostatic discharge element. Since it is connected to the ground region, the static electricity that has entered the radiation electrode flows to the one radiation electrode through the electrostatic discharge element, and flows out to the ground region through a separate electrostatic discharge element.

The invention according to claim 2 is the antenna device according to claim 1, wherein one radiation electrode connected to the ground region by using a separate electrostatic discharge element is entirely or partly more than the other radiation electrode. Also, the radiation electrode is the closest to the ground region.
With this configuration, all or a part of one radiation electrode is in a state of being connected close to the ground region, and the other radiation electrode is not connected to the ground region and is separated from the ground region. It is in. As a result, it is possible to minimize degradation of the antenna characteristics.

According to a third aspect of the present invention, in the antenna device according to the first or second aspect, the electrostatic discharge element interposed between the plurality of radiation electrodes is an ESD (ElectroStatic Discharge) suppressor. And a separate electrostatic discharge element connected to the ground region is an ESD suppressor, an inductor, or a resistor.
With this configuration, a plurality of radiation electrodes are connected by an ESD suppressor. However, since the capacity of the ESD suppressor is extremely small, the antenna characteristics are not deteriorated by the ESD suppressor.

According to a fourth aspect of the present invention, in the antenna device according to any one of the first to third aspects, the feeding electrode and the frequency variable circuit are formed on the dielectric chip, and all or a part of the plurality of radiation electrodes are formed. Is formed on a dielectric chip.
With this configuration, the components of the frequency variable circuit can be three-dimensionally mounted on the dielectric chip, so that the antenna device can be downsized accordingly. In addition, since the capacitive coupling at the open end of the radiation electrode can be strengthened, the high frequency resonance frequency can be easily controlled by the frequency variable circuit.

A fifth aspect of the present invention is the antenna device according to any one of the first to fourth aspects, wherein an auxiliary radiation electrode such as a metal plate is connected to any one of the plurality of radiation electrodes. And
With this configuration, the antenna characteristics can be further improved.

A sixth aspect of the present invention is the antenna device according to any one of the first to fifth aspects, wherein the frequency variable circuit includes a variable capacitance element such as a variable capacitance diode whose capacitance value can be changed by a control voltage. The configuration is a circuit.
With this configuration, it is possible to change each resonance frequency by changing the capacitance value of the variable capacitance element with the control voltage and changing the reactance value of the reactance variable circuit.

  According to a seventh aspect of the present invention, there is provided a wireless communication device including the antenna device according to any one of the first to sixth aspects.

  As described above in detail, according to the antenna device of the present invention, the static electricity that has entered the radiation electrode is blocked by the low-frequency cut capacitor, and the static electricity that has entered the radiation electrode is transferred to the single radiation electrode through the electrostatic discharge element. Since it can flow to the ground region through a separate electrostatic discharge element, the deterioration of the antenna characteristics can be prevented, and the flow of static electricity that has entered the radiation electrode can be prevented from flowing into the variable frequency circuit. There is an excellent effect that the outflow to the area can be achieved.

  Particularly, according to the inventions of claims 2 and 3, there is an effect that the deterioration of the antenna characteristics can be suppressed to the minimum.

  According to the invention of claim 4, there is an effect that the antenna device can be miniaturized and the high frequency resonance frequency can be easily controlled by the frequency variable circuit.

  According to the invention of claim 5, the antenna characteristics can be further improved.

  In addition, according to the wireless communication device of the present invention, there is an effect that transmission / reception with high resistance to static electricity and almost no deterioration in antenna characteristics is possible.

  The best mode of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic plan view showing an antenna apparatus according to a first embodiment of the present invention.
The antenna device 1 of this embodiment is provided in a wireless communication device such as a mobile phone.
As shown in FIG. 1, the antenna device 1 includes a feeding electrode 2, a frequency variable circuit 3, and a plurality of radiation electrodes 4-1 and 4-2, and is housed in a casing (not shown) of a wireless communication device. It is configured on the substrate 100.

  The power supply electrode 2 is patterned in the non-ground region 101 with one end 20 connected to the power supply unit 110. Specifically, the inductor 111 is connected to the power supply unit 110 and the one end 20 of the power supply electrode 2, the inductor 112 is connected to the power supply unit 110 and the ground region 102, and a matching circuit is connected to the inductors 111 and 112. Are formed on the non-ground region 101. Thereby, the one end part 20 of the power feeding electrode 2 is in a state of being connected to the power feeding part 110 through this matching circuit.

The frequency variable circuit 3 is a circuit for changing the resonance frequency of the radiation electrodes 4-1 and 4-2 described later, and is formed in the non-ground region 101. Specifically, a state where one end of the frequency variable circuit 3 is connected to the other end 21 of the feeding electrode 2 and the other end is connected to one end 40, 40 of the radiation electrode 4-1, 4-2, respectively. Therefore, it is interposed between the feeding electrode 2 and the radiation electrodes 4-1 and 4-2.
The frequency variable circuit 3 is a reactance variable circuit including variable capacitance diodes 31 and 32 which are variable capacitance elements whose capacitance value can be changed by a control voltage. Specifically, the series resistor 33 and the inductor 34 are connected between the other end 21 of the feeding electrode 2 and the one end 40 of the radiation electrode 4-1. A series inductor 35, variable capacitance diode 31, and inductor 36 are connected between the other end 21 of the feeding electrode 2 and one end 40 of the radiation electrode 4-2. Further, the variable capacitance diode 32 is connected between the cathode side of the variable capacitance diode 31 and the resistor 33 with the cathode side facing the cathode side of the variable capacitance diode 31.
The tuning voltage source 120 is connected to the cathode side of the variable capacitance diodes 31 and 32 via the resistor 121. Reference numeral 122 denotes a capacitor for cutting inflow of the RF signal to the current source.

The radiation electrode 4-1 as one radiation electrode is a U-shaped pattern in which the other end 41 is opened and the one end 40 is connected to the inductor 34 of the frequency variable circuit 3. The pattern is formed.
Similarly, the radiation electrode 4-2 is a U-shaped pattern in which the other end portion 41 is opened and the one end portion 40 is connected to the inductor 36 of the frequency variable circuit 3, and a pattern is formed on the non-ground region 101. Has been.
Such a radiation electrode 4-1 is disposed outside the radiation electrode 4-2, and the radiation electrode 4-1 is closer to the ground region 102 than the radiation electrode 4-2.

  With this configuration, the feeding electrode 2, the frequency variable circuit 3, and the radiation electrode 4-1 form, for example, an antenna portion having a low resonance frequency in the UHF band, and the power feeding electrode 2, the frequency variable circuit 3, and the radiation electrode 4- 2, for example, an antenna portion having a high resonance frequency can be formed. Then, by applying the tuning voltage Vc as the control voltage from the tuning voltage source 120 to the frequency variable circuit 3 and changing the reactance value of the frequency variable circuit 3, the resonance frequency of these antenna units can be changed.

Such an antenna device 1 has a countermeasure against static electricity.
That is, a low frequency cut capacitor 5-1 is provided on one end 40 of the radiation electrode 4-1, and the low frequency cut capacitor 5-1 is substantially variable in frequency with one end of the radiation electrode 4-1. It is in a state of being provided between the inductor 34 of the circuit 3. A low-frequency cut capacitor 5-2 is provided on one end portion 40 of the radiation electrode 4-2 . In effect, the low-frequency cut capacitor 5-2 is variable in frequency with one end of the radiation electrode 4-2. It is in a state of being provided between the inductor 36 of the circuit 3. For example, when the antenna device 1 is used in a high frequency band, the capacitance values of the low frequency cut capacitors 5-1 and 5-2 are preferably large. However, it is necessary to make it small in order to prevent low frequencies such as static electricity. For example, when using at a UHF band frequency of digital television broadcasting, it is preferable to use low frequency cut capacitors 5-1 and 5-2 of about 30 pF.
In addition, an ESD suppressor 6 that is an electrostatic discharge element is interposed between the radiation electrodes 4-1 and 4-2. Similarly to the low-frequency cut capacitors 5-1 and 5-2, when the antenna device 1 is used in a high-frequency band, the capacitance value of the ESD suppressor 6 is preferably small. For example, when used in the UHF band, it is preferable to use an ESD suppressor 6 of about 0.05 pF. In this way, by using the ESD suppressor 6 having a very small capacity, the radiation electrodes 4-1 and 4-2 can be kept open with respect to the high frequency in a normal state.
Further, an inductor 60, which is a separate electrostatic discharge element, is connected between the middle portion of the radiation electrode 4-1 close to the ground region 102 and the ground region 102. When the antenna device 1 is used in a high frequency band, the inductance value of the inductor 60 is preferably large. For example, when used at a frequency in the UHF band, it is preferable to use an inductor 60 of 160 nH or more.

Next, operations and effects of the antenna device of this embodiment will be described.
FIG. 2 is a schematic plan view showing an electrostatic discharge action when static electricity enters one of the plurality of radiation electrodes, and FIG. 3 shows the other radiation electrode among the plurality of radiation electrodes. It is a schematic plan view which shows the electrostatic discharge effect | action when it penetrates.
In FIG. 1, by using an antenna unit composed of the feeding electrode 2, the frequency variable circuit 3, and the radiation electrode 4-1, for example, transmission / reception can be performed at a low frequency in the UHF band. In addition, by using an antenna unit composed of the feed electrode 2, the frequency variable circuit 3, and the radiation electrode 4-2, for example, transmission and reception can be performed at a high frequency in the UHF band.
Then, by applying the tuning voltage Vc as the control voltage from the tuning voltage source 120 to the frequency variable circuit 3 and changing the reactance value of the frequency variable circuit 3, the resonance frequency of these antenna units can be changed.

  As described above, since the high frequency current flows through the radiation electrodes 4-1 and 4-2 during normal use, the ESD suppressor 6 having a small capacitance value functions as a weir against the high frequency current. For this reason, normally, the radiation electrodes 4-1 and 4-2 are open. Further, the inductor 60 also opens between the radiation electrode 4-1 and the ground region 102.

As shown in FIG. 2, when a human body or the like comes into contact with the radiation electrode 4-1, and the static electricity Q enters the radiation electrode 4-1, the static electricity Q passes through the radiation electrode 4-1, and the frequency variable circuit. Flows to the 3rd side. At this time, since the frequency of the static electricity Q is very low, the impedance of the ESD suppressor 6 is lowered, and the radiation electrodes 4-1 and 4-2 are short-circuited. As a result, part of the static electricity Q on the radiation electrode 4-1 enters the radiation electrode 4-2 through the ESD suppressor 6, and flows to the frequency variable circuit 3 side through the radiation electrode 4-2.
However, in the antenna device 1 of this embodiment, as described above, the low frequency cut capacitors 5-1 and 5-2 are provided at the one end portions 40 of the radiation electrodes 4-1 and 4-2 at the front stage of the frequency variable circuit 3. , 40, and in effect, low frequency cut capacitors 5-1 and 5-2 are provided between one end of the radiation electrodes 4-1 and 4-2 and the frequency variable circuit 3, respectively. Therefore , the static electricity Q toward the frequency variable circuit 3 is prevented by these low frequency cut capacitors 5-1 and 5-2.
And most of the static electricity Q flows out from the radiation electrode 4-1 to the ground region 102 through the inductor 60.

Also, as shown in FIG. 3, when a human body or the like comes into contact with the radiation electrode 4-2 and the static electricity Q enters the radiation electrode 4-2, the static electricity Q passes through the radiation electrode 4-2 and the frequency variable circuit. Flows to the 3rd side. At this time, a part of the static electricity Q on the radiation electrode 4-1 enters the radiation electrode 4-1 through the ESD suppressor 6, and flows to the frequency variable circuit 3 side through the radiation electrode 4-1.
However, even in this case, the low-frequency cut capacitors 5-1 and 5-2 block static electricity Q toward the frequency variable circuit 3 side. And most of the static electricity Q flows out from the radiation electrode 4-1 to the ground region 102 through the inductor 60.

As described above, according to the antenna device 1 of this embodiment, a countermeasure against static electricity is surely taken. And by adopting such a static electricity countermeasure structure, the antenna characteristics hardly deteriorate.
That is, only the radiation electrode 4-1 is connected to the ground region 102, and the other radiation electrode 4-2 is connected to the radiation electrode 4-1 via the ESD suppressor 6 and connected to the ground region 102. It has not been. Moreover, the radiation electrode 4-2 is away from the ground region 102. For this reason, the connection and proximity to the ground region 102 that causes the deterioration of the antenna characteristics may be performed only by the radiation electrode 4-1, and the deterioration of the antenna characteristics can be minimized. The ESD suppressor 6 normally has an open state between the radiation electrodes 4-1 and 4-2, and there is no deterioration of the antenna characteristics due to the ESD suppressor 6 being interposed.

Next explained is the second embodiment of the invention.
4 is a schematic perspective view showing an antenna device according to a second embodiment of the present invention. FIG. 5 is an exploded perspective view showing a state where a dielectric chip is separated from a substrate. FIG. It is an expanded view of a chip.
This embodiment differs from the first embodiment in that the components of the antenna device are assembled on a dielectric chip.
In FIG. 4, reference numeral 7 denotes a dielectric chip. On the dielectric chip 7, all of the feeding electrode 2 and the frequency variable circuit 3 and most of the radiation electrodes 4-1 and 4-2 are formed.

  Specifically, the power supply electrode 2 is formed on the right edge of the front surface 71 of the dielectric chip 7, and is connected to the power supply unit 110 through a conductor pattern 113 formed on the non-ground region 101. The variable capacitance diodes 31 and 32, the resistor 33, and the inductors 34 to 36 that are components of the frequency variable circuit 3 are also mounted on the front surface 71.

The radiation electrode 4-1 is formed by one end 40, partial electrodes 4-1 a, 4-1 b and 4-1 d and the other end 41. Specifically, one end portion 40 of the radiation electrode 4-1 is provided on the front surface 71, and a partial electrode 4-1 a continuous with the one end portion 40 is provided from the lower surface 74 to the rear surface 73. The end 4-1a ′ of the partial electrode 4-1a provided at the left corner of the lower surface 74 is connected from above to the partial electrode 4-1b provided on the substrate surface side. The partial electrode 4-1b is connected to a partial electrode 4-1d (indicated by a two-dot chain line) provided on the back side of the substrate through the through hole 4-1c. -1e to the other end 41 of the substrate surface.
On the other hand, the radiation electrode 4-2 is formed by one end 40, a partial electrode 4-2a, and the other end 41. Specifically, one end portion 40 of the radiation electrode 4-2 is provided on the front surface 71 of the dielectric chip 7, and a partial electrode 4-2a continuous with the one end portion 40 via the low frequency cut capacitor 5-2 is provided. The upper edge of the front surface 71, the left edge of the upper surface 72, and the upper edge and the right edge of the rear surface 73 are provided. An end 4-2a ′ of the partial electrode 4-2a provided at the right corner of the lower surface 74 is connected from above to the other end 41 provided on the substrate surface side.

The low frequency cut capacitors 5-1 and 5-2 are mounted on the one end portions 40 and 40 of the radiation electrodes 4-1 and 4-2 provided on the front surface 71 of the dielectric chip 7 as described above. Substantially, the low frequency cut capacitors 5-1 and 5-2 are provided between the one ends of the radiation electrodes 4-1 and 4-2 and the frequency variable circuit 3, respectively. The ESD suppressor 6 is connected between the other end 41 of the radiation electrode 4-1 and the other end 41 of the radiation electrode 4-2. The inductor 60 is mounted on the conductor pattern 130 extending from the other end 41 of the radiation electrode 4-1 to the ground region 102.
In the first embodiment, the ESD suppressor 6 and the inductor 60 are mounted in the middle of the radiation electrodes 4-1, 4-2. In this embodiment, the open ends of the radiation electrodes 4-1, 4-2. 41.

In this embodiment, as described above, since the components of the frequency variable circuit 3 are three-dimensionally mounted on the dielectric chip 7, the antenna device 1 can be reduced in size. Further, since the capacitive coupling in the vicinity of the open ends 41 and 41 of the radiation electrodes 4-1 and 4-2 is strengthened, the high-frequency resonance frequency can be easily controlled by the frequency variable circuit 3 accordingly.
Since other configurations, operations, and effects are the same as those in the first embodiment, description thereof is omitted.

Next explained is the third embodiment of the invention.
FIG. 7 is a perspective view showing an antenna apparatus according to a third embodiment of the present invention.
This embodiment is different from the third embodiment in that a metal plate as an auxiliary radiation electrode is provided.
Specifically, the metal plate 8 bent into a distance L shape was erected on the other end 41 of the radiation electrode 4-1.
With this configuration, the antenna characteristics of the antenna device 1 can be further improved.
Since other configurations, operations, and effects are the same as those of the third embodiment, description thereof is omitted.

Next explained is the fourth embodiment of the invention.
FIG. 8 is a schematic plan view showing an antenna apparatus according to a fourth embodiment of the present invention.
This embodiment differs from the first to third embodiments in that a large number of radiation electrodes 4-1 to 4-n are provided to achieve multiple resonances.
Specifically, as shown in FIG. 8, n-2 number (n is an integer of 3 or more) radiation electrodes 4-3 to 4-n are sequentially arranged between the radiation electrodes 4-1 and 4-2. . The variable frequency circuit 3 includes a resistor 33 and an inductor 34 connected to the radiation electrode 4-1 and a series inductor 35, a variable capacitance diode 31 and an inductor 36 connected to the radiation electrode 4-2. The series circuit of the inductor 33 and the inductor 34 is connected in parallel, and the variable capacitance diode 32 is connected to the cathode side of the variable capacitance diode 31 from each series circuit.
Then, one end 40 of the radiation electrodes 4-3 to 4-n is connected to a series circuit of a resistor 33 and an inductor 34, and the low frequency cut capacitors 5-3 to 5-n are connected to each one end 40. the Rukoto provided, the low-frequency cut-off capacitor 5-3~5-n has a state respectively provided between one end and the frequency-variable circuit 3 of the radiation electrode 4-3~4-n.
Similar to the first embodiment, an inductor 60 is provided on the radiation electrode 4-1 closest to the ground region 102, and the inductor 60 is connected to the ground region 102. An ESD suppressor 6 is connected between the n number of radiation electrodes 4-1 to 4-n.
With this configuration, it is possible to realize a multi-resonance antenna device capable of taking countermeasures against static electricity without deteriorating antenna characteristics.
Since other configurations, operations, and effects are the same as those in the first to third embodiments, description thereof is omitted.

In addition, this invention is not limited to the said Example, A various deformation | transformation and change are possible within the range of the summary of invention.
For example, in the above-described embodiment, an example in which the inductor 60 is used as a separate electrostatic discharge element connected to the radiation electrode 4-1 and the ground region 102 has been shown. However, as this separate electrostatic discharge element, Of course, an ESD suppressor, a resistor, or the like can also be employed.
In the second and third embodiments, an example in which a part of the radiation electrodes 4-1 and 4-2 is formed on the dielectric chip 7 is shown. However, all of the radiation electrodes 4-1 and 4-2 are shown. Of course, may be formed on the dielectric chip 7.

1 is a schematic plan view showing an antenna device according to a first embodiment of the present invention. It is a schematic top view which shows the static electricity discharge | release effect | action when static electricity enters into one radiation electrode among several radiation electrodes. It is a schematic top view which shows the static electricity discharge | release effect | action when static electricity enters into the other radiation electrode among several radiation electrodes. It is a schematic perspective view which shows the antenna apparatus which concerns on 2nd Example of this invention. It is a disassembled perspective view which shows the state which isolate | separated the dielectric chip from the board | substrate. It is an expanded view of a dielectric chip. It is a perspective view which shows the antenna apparatus which concerns on 3rd Example of this invention. It is a schematic plan view which shows the antenna apparatus which concerns on 4th Example of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Antenna apparatus, 2 ... Feed electrode, 3 ... Frequency variable circuit, 4-1, 4-2-2-n ... Radiation electrode, 4-1a, 4-1b, 4-1d, 4-2a ... Partial electrode, 4-1c, 4-1e ... through hole, 4-1a ', 4-2a' ... end, 5-1,5-2 to 5-n ... low frequency cut capacitor, 6 ... ESD suppressor, 7 ... dielectric Body chip, 8 ... Metal plate, 20, 40 ... One end, 21, 41 ... Other end, 31, 32 ... Variable capacitance diode, 33 ... Resistor, 34-36, 60 ... Inductor, 71 ... Front, 72 ... upper surface, 73 ... rear surface, 74 ... lower surface, 100 ... substrate, 101 ... non-ground region, 102 ... ground region, 110 ... power feeding section.

Claims (7)

A power supply electrode with one end connected to the power supply unit, a frequency variable circuit connected to the other end of the power supply electrode, and one end connected to the other end of the power supply electrode via the frequency variable circuit An antenna device comprising a plurality of radiation electrodes, the other end of which is opened, in a non-ground region of the substrate,
A low frequency cut capacitor is provided between one end of the plurality of radiation electrodes and the frequency variable circuit ,
In addition, an electrostatic discharge element is interposed between the plurality of radiation electrodes, and
One radiation electrode of the plurality of radiation electrodes is connected to the ground region using an electrostatic discharge element separate from the electrostatic discharge element.
An antenna device characterized by that. The one radiation electrode connected to the ground region by using the separate electrostatic discharge element is a radiation electrode whose whole or a part thereof is closest to the ground region than the other radiation electrodes.
The antenna device according to claim 1. The electrostatic discharge element interposed between the plurality of radiation electrodes is an ESD (ElectroStatic Discharge) suppressor,
The separate electrostatic discharge element connected to the one radiation electrode and the ground region is either an ESD suppressor, an inductor, or a resistor.
The antenna device according to claim 1 or 2, wherein While forming the feeding electrode and the frequency variable circuit on the dielectric chip,
All or part of the plurality of radiation electrodes are formed on the dielectric chip.
The antenna device according to any one of claims 1 to 3, wherein the antenna device is provided. An auxiliary radiation electrode such as a metal plate was connected to one of the plurality of radiation electrodes.
The antenna device according to any one of claims 1 to 4, wherein the antenna device is provided. The frequency variable circuit is a reactance variable circuit including a variable capacitance element such as a variable capacitance diode whose capacitance value can be changed by a control voltage.
The antenna device according to any one of claims 1 to 5, wherein the antenna device is provided. Comprising the antenna device according to any one of claims 1 to 6.
A wireless communication device.

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