WO2016186090A1

WO2016186090A1 - Antenna device and electronic apparatus

Info

Publication number: WO2016186090A1
Application number: PCT/JP2016/064543
Authority: WO
Inventors: 伊藤宏充
Original assignee: 株式会社村田製作所
Priority date: 2015-05-19
Filing date: 2016-05-17
Publication date: 2016-11-24
Also published as: CN207910064U

Abstract

An antenna device (101) comprising: a conductive radiation element (1); a power supply coil (3) connected to a second power supply circuit (82) for a second frequency band; and a choke coil (L2) connected to the radiation element (1). The radiation element (1) is connected to a first power supply circuit (81) for a first frequency band and is used as a radiation element for a standing wave antenna that contributes to field emission. A loop is formed that includes the radiation element (1) and the choke coil (L2). The power supply coil (3) magnetically couples or electromagnetically couples to the choke coil (L2) in the second frequency band. As a result, the loop acts as a magnetic field radiation type antenna that contributes to magnetic field radiation.

Description

ANTENNA DEVICE AND ELECTRONIC DEVICE

The present invention relates to an antenna device, and more particularly to an antenna device that is also used in a communication system using communication signals having different frequency bands. The present invention also relates to an electronic apparatus including the antenna device.

With the recent increase in functionality of communication devices, for example, mobile phone terminals and so-called smartphones are equipped with antennas for various communication (broadcasting) systems such as GPS, wireless LAN, and terrestrial digital broadcasting, as well as communication antennas. It has become like this.

For example, Patent Document 1 discloses a small antenna device that can be used in a plurality of systems having different frequency bands. This antenna device connects a radiation element of an electric field antenna, a first frequency band power supply circuit connected to the radiation element, a ground conductor disposed opposite to the radiation element, and the radiation element and the ground conductor. An inductor, a power feeding coil, and a power feeding circuit of a second frequency band connected to the power feeding coil are provided.

These radiating elements, inductor and ground conductor are connected in series to form a loop, and the loop is coupled to the feeding coil. The inductor is an element whose impedance approaches an open state in the first frequency band and approaches a short state in the second frequency band. For this reason, the radiating element acts as an electric field antenna element for the first frequency band, and the loop acts as an antenna element for the second frequency band.

International Publication No. 2014/098024

However, in the configuration disclosed in Patent Document 1, depending on the positional relationship between the loop and the feeding coil, the loop and the feeding coil may not be sufficiently coupled, and the communication characteristics of the antenna device may be deteriorated as a result. There is.

An object of the present invention is to provide a small antenna device that can be used by a plurality of systems having different frequency bands and has good communication characteristics with a simple configuration. Another object is to provide an electronic device including the antenna device.

(1) The antenna device of the present invention
A radiating element of a standing wave antenna having conductivity and connected to the first feeding circuit for the first frequency band;
A feeding coil connected to the second feeding circuit for the second frequency band;
A choke coil connected to the radiating element;
With
A loop of a magnetic field radiation type antenna is configured including the radiation element and the choke coil,
The feeding coil is magnetically coupled or electromagnetically coupled to the choke coil in the second frequency band.

In this configuration, the radiating element of the standing wave antenna acts as an antenna in the first frequency band, and the loop of the magnetic field radiation antenna acts as an antenna in the second frequency band. An antenna device that can be used can be realized.

In this configuration, the choke coil having a large inductance ratio and the feeding coil are coupled to the inductance of the entire loop in the second frequency band. For this reason, the coupling coefficient between the entire loop and the feeding coil is increased, and the characteristics of the magnetic field radiation antenna can be improved as a result.

Furthermore, in this configuration, in the second frequency band, the feeding coil is coupled to the loop, and the loop functions as a booster antenna for the feeding coil. Therefore, the effective coil opening that functions as an antenna is larger and the range and distance for radiating (magnetizing) the magnetic flux are larger than when only the feeding coil is used, so that it can be easily coupled with the antenna coil on the communication partner side. Become. Therefore, an antenna device having good communication characteristics can be realized with a simple configuration without using a large antenna coil.

(2) Preferably, the radiating element generates a standing wave in a first frequency band, and the loop resonates in a second frequency band lower than the first frequency band. With this configuration, a small first frequency band antenna and second frequency band antenna having excellent communication characteristics can be configured.

(3) In the above (1) or (2), it is preferable that the feeding coil and the choke coil are separately provided. In this configuration, since the choke coil and the power feeding coil have different structures, the degree of freedom in arranging the choke coil and the power feeding coil is high.

(4) In any one of the above (1) to (3), the choke coil preferably has a non-magnetic core or is an air core. With this configuration, the magnetic loss of the choke coil in the first frequency band can be eliminated.

(5) In any one of the above (1) to (4), it is preferable to further include a ground conductor constituting a part of the loop. In this configuration, since a ground conductor such as a substrate is used as a part of the loop, a loop acting as a magnetic field radiation antenna can be easily formed. Therefore, it is not necessary to separately form a conductor that constitutes a part of the loop, and the manufacturing is easy and the cost can be reduced.

(6) In the above (5), the choke coil may be connected between the radiating element and the ground conductor.

(7) In the above (1) to (6), it is preferable that at least two adjacent radiating elements are provided, and the choke coil is connected between the adjacent radiating elements. In this configuration, for example, a choke coil that is equivalently open in a specific frequency band (first frequency band) can be connected between adjacent radiating elements. It can be used as a radiating element for a standing wave antenna. Therefore, it is possible to realize an antenna device adapted to a system using at least two different frequency bands (both being the first frequency band).

(8) The electronic device of the present invention
An antenna device and a housing;
The antenna device is
A radiating element of a standing wave antenna having conductivity and connected to the first feeding circuit for the first frequency band;
A feeding coil connected to the second feeding circuit for the second frequency band;
A choke coil connected to the radiating element,
A loop of a magnetic field radiation antenna including the radiation element and the choke coil is configured,
The choke coil is magnetically coupled or electromagnetically coupled to the feeding coil in the second frequency band.

This configuration makes it possible to realize an electronic device equipped with an antenna device that can be used in a plurality of systems having different frequency bands.

(9) In the above (8), it is preferable that part or all of the radiating element is part or all of the casing. In this configuration, a radiating element that acts as a standing wave antenna can be easily configured by using the housing. Therefore, it is not necessary to separately form a radiating element, and manufacturing is easy and cost reduction can be achieved.

According to the present invention, it is possible to realize a small antenna device that can be used by a plurality of systems having different frequency bands and has good communication characteristics with a simple configuration. In addition, an electronic device including the antenna device can be realized.

1A is a plan view of the antenna device 101 according to the first embodiment, FIG. 1B is a cross-sectional view taken along the line AA in FIG. 1A, and FIG. FIG. 2 is a cross-sectional view taken along the line BB in FIG. FIG. 2 is an equivalent circuit diagram of the antenna device 101 using lumped constant elements. FIG. 3A is an equivalent circuit diagram of the antenna device 101 in the UHF band or SHF band, and FIG. 3B is an equivalent circuit diagram of the antenna device 101 in the HF band. 4A is an equivalent circuit diagram of the antenna device 101 in the HF band, and FIG. 4B is an equivalent circuit diagram of the antenna device 100 of the comparative example in the HF band. FIG. 5A is a plan view of the antenna device 102 according to the second embodiment, FIG. 5B is a cross-sectional view taken along the line CC in FIG. 5A, and FIG. FIG. 6 is a DD cross-sectional view in FIG. FIG. 6 is a plan view of the antenna device 103 according to the third embodiment. FIG. 7 is a plan view of an antenna device 104 according to the fourth embodiment. FIG. 8 is an equivalent circuit diagram of the antenna device 105 according to the fifth embodiment using lumped constant elements. FIG. 9 is a plan view of an antenna device 106A according to the sixth embodiment. FIG. 10 is a plan view of an antenna device 106B according to the sixth embodiment. FIG. 11A is a plan view of the antenna device 107 according to the seventh embodiment, FIG. 11B is a cross-sectional view taken along line EE in FIG. 11A, and FIG. FIG. 12 is a sectional view taken along line FF in FIG. FIG. 12 is an equivalent circuit diagram of the antenna device 107 using lumped constant elements. 13A is a plan view of the antenna device 108 according to the eighth embodiment, FIG. 13B is a cross-sectional view taken along the line GG in FIG. 13A, and FIG. FIG. 14 is a cross-sectional view taken along line HH in FIG. FIG. 14A is a plan view of the antenna device 109 according to the ninth embodiment, and FIG. 14B is a cross-sectional view taken along the line II in FIG. FIG. 15A is a plan view of the antenna device 110 according to the tenth embodiment, and FIG. 15B is a JJ cross-sectional view in FIG. 15A. FIG. 16A is a plan view of the antenna device 111 according to the eleventh embodiment, and FIG. 16B is a cross-sectional view taken along the line KK in FIG. FIG. 17 is a cross-sectional view of the antenna device 112 according to the twelfth embodiment. FIG. 18A is a cross-sectional view of the antenna device 113A according to the thirteenth embodiment, and FIG. 18B is a cross-sectional view of the antenna device 113B. FIG. 19 is a plan view of an antenna device 114 according to the fourteenth embodiment. FIG. 20 is an external perspective view showing the radiating element 1D and the conductor plate 5D in the antenna device 115A according to the fifteenth embodiment. FIG. 21 is an external perspective view showing the radiating element 1E and the conductor plate 5E in the antenna device 115B. FIG. 22 is an external perspective view showing the radiation element 1F and the conductor plate 5F in the antenna device 115C. FIG. 23 is an external perspective view showing the radiating element 1G and the conductor plate 5G in the antenna device 115D.

Hereinafter, a plurality of embodiments for carrying out the present invention will be described by giving some specific examples with reference to the drawings. In each figure, the same reference numerals are assigned to the same portions. Each embodiment is an exemplification, and a partial replacement or combination of the configurations shown in different embodiments is possible.

The antenna devices of some embodiments described below are provided in electronic devices typified by so-called smartphones and tablet terminals. For example, a plurality of systems having different frequency bands such as HF band, UHF band, and SHF band (GPS ( (Global Positioning System), Wi-Fi (registered trademark), NFC (Near Field Communication), etc.).

<< First Embodiment >>
1A is a plan view of the antenna device 101 according to the first embodiment, FIG. 1B is a cross-sectional view taken along the line AA in FIG. 1A, and FIG. FIG. 2 is a cross-sectional view taken along the line BB in FIG. Note that in FIGS. 1B and 1C, the thickness of each part is exaggerated. The same applies to the sectional views in the following embodiments.

FIG. 2 is an equivalent circuit diagram of the antenna device 101 using lumped constant elements. In FIG. 2, the radiating element 1 is represented by an inductor L1, the choke coil L2 is represented by an inductor L2, and the feeding coil 3 is represented by an inductor L3. In FIG. 2, the mutual inductance between the feeding coil 3 and the radiating element 1 is represented by M13, and the mutual inductance between the feeding coil 3 and the choke coil L2 is represented by M23. The same applies to equivalent circuit diagrams in the following embodiments.

The antenna device 101 includes a radiating element 1,

substrates

6A and 6B, a battery pack 8, a choke coil L2, a capacitor C1, a first feeding circuit 81, a second feeding circuit 82, a feeding coil 3,

reactance elements

61 and 62, and a capacitor C41, C42, C43, C44 are provided.

The radiating element 1 is a flat plate having a rectangular planar shape and conductivity. The radiating element 1 has a longitudinal direction that coincides with the lateral direction (X direction in FIG. 1A), and has a first end E1 and a second end E2 at both ends in the longitudinal direction. The radiating element 1 is a part of the back housing of an electronic device such as a smartphone, and is made of metal, graphite, or the like.

The

substrates

6A and 6B are insulating flat plates having a rectangular planar shape. The substrate 6A includes a flat ground conductor 4 inside. The

substrates

6A and 6B are arranged side by side in the vertical direction (Y direction in FIG. 1A) with the battery pack 8 interposed therebetween, and are arranged on the same plane (see FIG. 1B). The board 6A and the board 6B are connected by a coaxial cable or the like (not shown).

Choke coil L2, capacitor C1, first power supply circuit 81, second power supply circuit 82, power supply coil 3,

reactance elements

61 and 62, and capacitors C41 to C44 are formed on one main surface of substrate 6A (substrate 6A in FIG. 1A). Mounted on the front side). The choke coil L2 is a chip coil in which a coil conductor is wound around, for example, an alumina (Al ₂ O ₃ ) ceramic core, and the capacitors C1, C41 to C44 are capacitor components such as a chip capacitor.

The choke coil L2 is connected between the radiating element 1 and the ground conductor 4. Specifically, one end of the choke coil L2 is connected to the vicinity of the first end E1 of the radiating element 1 via the connection conductor 71A and the connection pin 7, and the other end of the choke coil L2 is connected to the connection conductor 72A and the interlayer connection. The conductor 52A is connected to the ground conductor 4. The

connection conductors

71A and 72A are linear (I-shaped) conductor patterns formed on one main surface of the substrate 6A. The connection pin 7 is, for example, a movable probe pin, and the interlayer connection conductor 52A is, for example, a via conductor.

The capacitor C1 is connected between the radiation element 1 and the ground conductor 4. Specifically, one end of the capacitor C1 is connected to the vicinity of the second end E2 of the radiating element 1 via the connection conductor 73A and the connection pin 7, and the other end of the capacitor C1 is connected to the connection conductor 74A and the interlayer connection conductor ( It is connected to the ground conductor 4 via a not shown). The

connection conductors

73A and 74A are linear (I-shaped) conductor patterns formed on one main surface of the substrate 6A.

Therefore, as shown in FIG. 1A, a loop including the radiating element 1, the ground conductor 4, the choke coil L2, and the capacitor C1 is formed.

The first power supply circuit 81 is an IC for UHF band or SHF band (first frequency band). The input / output part of the first power supply circuit 81 is connected to the vicinity of the second end E2 in the longitudinal direction of the radiating element 1 via the connection conductor, the connection pin 7 and the reactance element 61 formed on one main surface of the substrate 6A. Is done. The reactance element 61 is an electronic component such as a chip capacitor, and the first power supply circuit 81 is a power supply circuit of a wireless LAN communication system of 2.4 GHz band, for example.

The connection portion between the radiating element 1 including the reactance element 62 and the ground is a stub provided for matching the antenna including the radiating element 1 and the first feeding circuit 81, and the reactance element 62 is provided on one main surface of the substrate 6A. It is connected to the vicinity of the second end E 2 of the radiating element 1 through the formed connection conductor and connection pin 7. The reactance element 62 is an electronic component such as a chip capacitor. The reactance element 62 may be provided with a plurality of reactance elements as necessary. However, the reactance element 62 is not an essential configuration, and may be a configuration without a stub.

The second power supply circuit 82 is a balanced input / output HF band (second frequency band) IC. The input / output unit of the second power supply circuit 82 is connected to the power supply coil 3 via capacitors C41 to C44. A series circuit of capacitors C41 and C42 is connected in parallel to the feed coil 3, and the feed coil 3 and the capacitors C41 and C42 constitute an LC resonance circuit. The second power feeding circuit 82 feeds a communication signal in the HF band (second frequency band) to the LC resonance circuit via the capacitors C43 and C44. The second feeding circuit 82 is, for example, an RFIC element for RFID of 13.56 MHz, and the feeding coil 3 is, for example, a laminated coil (coil antenna) in which a coil conductor is formed on a magnetic ferrite core.

The feeding coil 3 is magnetically coupled or electromagnetically coupled (magnetic field coupling and electric field coupling) with a loop including the radiating element 1, the ground conductor 4, the choke coil L2, and the capacitor C1.

Specifically, the feeding coil 3 is disposed between the radiating element 1 and the ground conductor 4 in a plan view and at a position where the coil opening is along the edge of the radiating element 1. That is, the coil opening of the feeding coil 3 is arranged so as to face the radiation element 1 in plan view. Therefore, the feeding coil 3 is mainly magnetically coupled to the radiating element 1. In addition to the magnetic field coupling, electromagnetic field coupling including electric field coupling is performed.

Further, the feeding coil 3 is arranged in the vicinity of the first end E1 of the radiating element 1 in plan view. That is, the feeding coil 3 is disposed in the vicinity of the choke coil L2. Therefore, the feeding coil 3 is mainly magnetically coupled to the choke coil L2 having a large inductance ratio with respect to the inductance of the entire loop in the HF band (second frequency band) (broken line arrow φ1 in FIG. 1A). See). In addition to the magnetic field coupling, the electric field coupling is slightly performed and the electromagnetic field coupling is performed.

In the present application, “the vicinity” of the choke coil L2 does not mean only the vicinity of the choke coil L2. A range in which the feeding coil 3 is magnetically coupled or electromagnetically coupled to the choke coil L 2 so that the loop functions as a booster antenna for the feeding coil 3. For example, the distance (D1 in FIG. 1C) between the choke coil L2 and the feeding coil 3 constituting a part of the loop is the maximum distance between the respective parts of the loop and the feeding coil 3 (FIG. 1 (C) is equal to or less than D2) (when D1 ≦ D2 holds), it is assumed that the feeding coil 3 is arranged “in the vicinity” of the choke coil L2.

3A is an equivalent circuit diagram of the antenna device 101 in the UHF band or SHF band, and FIG. 3B is an equivalent circuit diagram of the antenna device 101 in the HF band. In FIG. 3A, the

reactance elements

61 and 62 are represented by capacitors C61 and C62.

In the UHF band or SHF band (first frequency band), the capacitor C1 has a low impedance and is equivalently short-circuited. Therefore, as shown by the grounding end SP in FIG. 3A, the radiating element 1 is grounded at a predetermined position. The choke coil L2 has a high impedance in the UHF band or the SHF band (first frequency band) and is equivalently open. Therefore, one end of the radiating element 1 is opened as indicated by the open end OP in FIG.

The first power supply circuit 81 supplies voltage with the connection point of the radiating element 1 as a power supply point. In the UHF band or the SHF band (first frequency band), the open end OP of the radiating element 1 resonates so that the current intensity is zero and the ground terminal SP is zero voltage intensity. In other words, the length of the radiating element 1 is determined so as to resonate in the UHF band or the SHF band. However, the radiating element 1 resonates in the fundamental mode in the low band in the frequency band of 700 MHz to 2.4 GHz and resonates in the higher order mode in the high band. Therefore, in the UHF band or SHF band (first frequency band), a current flows in a region indicated by a solid arrow in FIG.

Thus, in the UHF band or the SHF band (first frequency band), a standing wave of current intensity and voltage intensity is generated in the radiating element 1, and the radiating element 1 contributes to electromagnetic wave radiation for far-field communication. Acts as an F-type antenna. In addition, although an inverted F type antenna is illustrated here, a patch antenna such as a monopole antenna, a single wavelength loop antenna, an inverted L type antenna, a plate-like inverted F antenna (PIFA), a slot antenna, a notch antenna, The present invention can be similarly applied to other standing wave type antennas in which standing waves of current intensity and voltage intensity due to resonance are generated on the radiating element.

On the other hand, in the HF band (second frequency band), as shown in FIG. 3B, a loop including the radiating element 1 (inductor L1), the ground conductor 4, the choke coil L2, and the capacitor C1 forms an LC resonance circuit. Constitute. As described above, the feeding coil 3 is mainly magnetically coupled to the loop constituting the LC resonance circuit.

The above loop undergoes LC resonance in the HF band, and a resonance current flows through the edge of the radiating element 1 and the choke coil L2. In other words, circuit constants such as the length of the radiating element 1 and reactance components of the choke coil L2 and the capacitor C1 are determined so as to resonate in the HF band. Therefore, in the HF band (second frequency band), a current flows in a region indicated by a dashed arrow in FIG.

In this way, in the HF band (second frequency band), the loop including the radiating element 1, the ground conductor 4, the choke coil L2, and the capacitor C1 serves as a magnetic field radiation antenna that contributes to magnetic field radiation for near field communication. Works. Here, in the HF band (second frequency band), the length of the loop is sufficiently short with respect to the wavelength, and is preferably 1/10 or less of the wavelength. Therefore, the loop is a minute loop antenna for communication by magnetic field coupling. It has become. In the HF band (second frequency band), the loop part hardly emits electromagnetic waves.

The

reactance elements

61 and 62 have a high impedance in the HF band (second frequency band), and the first power supply circuit 81 is not equivalently connected. Therefore, the first power supply circuit 81 is in the HF band. Does not affect the communication. The choke coil L2 has a high impedance in the UHF band or the SHF band (first frequency band), and the choke coil L2 is not equivalently connected. Therefore, since the loop including the choke coil L2 is in an open state, a UHF band or SHF band communication signal does not flow through the second power feeding circuit 82, and the second power feeding circuit 82 is used for UHF band or SHF band communication. Does not affect.

Next, in the HF band (second frequency band), the coupling between the loop (the radiating element 1 and the choke coil L2) and the feeding coil 3 will be described with reference to the drawings. 4A is an equivalent circuit diagram of the antenna device 101 in the HF band, and FIG. 4B is an equivalent circuit diagram of the antenna device 100 of the comparative example in the HF band. In addition, even if it is the structure of the comparative example demonstrated by FIG. 4 (B), it can be shared by several systems from which a frequency band differs, and there exists an effect of this invention. However, as described below, the inventors have found that the configuration of FIG. 4A is preferable from the viewpoint of the characteristics of the magnetic field radiation antenna.

As shown in FIG. 4B, the antenna device 100 of the comparative example has a radiating element and a choke coil L2 connected in series in the HF band (second frequency band), and the mutual inductance M13 and the mutual inductance M23 are , One is depolarized and the other is additive. Therefore, when the feeding coil and the loop are coupled, the current generated by mutual induction between the feeding coil (inductor L3) and the radiating element (inductor L1), the feeding coil (inductor L3), and the choke coil (inductor L2). The current generated by mutual induction between the two cancels out. Therefore, the coupling coefficient between the entire loop and the feeding coil is lowered, and the characteristics of the magnetic field radiation antenna are consequently lowered.

On the other hand, in the antenna device 101 according to the present embodiment, as shown in FIG. 4A, in the HF band (second frequency band), a radiating element and a choke coil are connected in series. The inductance M23 is both depolarized or additive. Therefore, when the feeding coil and the loop are coupled, the current generated by mutual induction between the feeding coil (inductor L3) and the radiating element (inductor L1), the feeding coil (inductor L3), and the choke coil (inductor L2). And the current generated by mutual induction between the two reinforce each other. Therefore, the coupling coefficient between the entire loop and the feeding coil is increased, and the characteristics of the magnetic field radiation antenna are consequently increased.

As described above, when the feeding coil 3 and the loop are coupled, a current generated by mutual induction between the feeding coil 3 and the radiating element 1 and a current generated by mutual induction between the feeding coil 3 and the choke coil L2. Are configured to be in phase (in the same direction).

According to this embodiment, the following effects are obtained.

(A) In the antenna device 101, the radiating element 1 of the standing wave antenna acts as an antenna in the UHF band or SHF band (first frequency band), and the loop of the magnetic field radiation antenna is in the HF band (second frequency band). Therefore, it is possible to realize an antenna device that can be used in a plurality of systems having different frequency bands. In addition, an electronic apparatus including the antenna device 101 that can be shared by a plurality of systems having different frequency bands can be realized.

(B) In the antenna device 101, in the HF band (second frequency band), the choke coil L2 and the feeding coil 3 having a large inductance ratio per region with respect to the inductance of the entire loop are coupled. Therefore, the coupling coefficient between the entire loop and the feeding coil 3 is increased, and the characteristics of the magnetic field radiation antenna can be improved as a result. In the present embodiment, an example in which the feeding coil 3 and the choke coil L2 and the feeding coil 3 and the radiating element 1, the loop including the ground conductor 4, the choke coil L2, and the capacitor C1 are coupled is shown. If the coil 3 and the choke coil L2 are coupled, the above effect can be obtained.

(C) In the antenna device 101, in the HF band (second frequency band), the feeding coil 3 is coupled to the loop, and the loop functions as a booster antenna for the feeding coil 3. Therefore, compared to the case of only the feeding coil 3, the effective coil opening that functions as an antenna is increased, and the range and distance for radiating (magnetizing) magnetic flux is increased. It becomes easy. Therefore, an antenna device having good communication characteristics can be realized with a simple configuration without using a large antenna coil.

(D) Since the antenna device 101 uses a part of the housing for the radiating element 1, the radiating element of the magnetic field radiation antenna can be easily configured. Therefore, it is not necessary to separately form the radiating element and the conductive member, and the manufacturing is easy and the cost can be reduced.

(E) Since the antenna device 101 does not directly connect the second feeding circuit 82 in the HF band (second frequency band) to the radiating element 1, the mounting position of the feeding coil 3 and the second feeding circuit 82 is high. The conductor pattern formed on the one main surface of the substrate 6A can also be simplified.

(F) Since the antenna device 101 uses a ground conductor such as a substrate as a part of the loop, a loop that acts as a magnetic field radiation antenna can be easily formed. Therefore, it is not necessary to separately form a conductor that constitutes a part of the loop, and the manufacturing is easy and the cost can be reduced.

(G) Since the choke coil L2 according to the present embodiment has a non-magnetic core, it does not have a magnetic core. Therefore, the magnetic material loss of the choke coil L2 in the UHF band or SHF band (first frequency band) can be eliminated. The choke coil L2 may have an air core.

(H) The antenna device 101 has a structure in which the feeding coil 3 and the choke coil L2 are separately provided. That is, since the power feeding coil 3 and the choke coil L2 have different structures, the degree of freedom in arrangement of the power feeding coil 3 and the choke coil L2 is high.

(I) In the antenna device 101, the choke coil L2 constituting a part of the loop is connected in the vicinity of the first end E1 of the radiating element 1. Further, the capacitor C1 constituting a part of the loop is connected to the vicinity of the second end E2 of the radiating element 1. Therefore, the effective coil opening of the loop of the magnetic field radiation antenna including the radiating element 1, the ground conductor 4, the choke coil L2, and the capacitor C1 is increased, and the range in which magnetic flux is radiated (magnetized) is increased. It becomes easy to couple with the antenna coil on the communication partner side. Therefore, an antenna device having good communication characteristics can be realized with a simple configuration without using a large antenna coil.

Note that “near the first end” and “near the second end” of the radiating element 1 do not mean only the very vicinity of the edge of the radiating element 1 in the longitudinal direction (X direction). The loop acts as a magnetic field radiation type antenna that contributes to magnetic field radiation, and means a range in which an opening area that enables magnetic field coupling with the communication partner antenna can be secured. For example, a range from the first end of the radiating element 1 to the third of the lateral length of the radiating element 1 in the lateral direction (X direction) is referred to as “near the first end”. For example, a range from the second end of the radiating element 1 in the lateral direction (X direction) to 1/3 of the lateral length of the radiating element 1 is referred to as “near the second end”.

In the embodiments described below, the “standing wave antenna” is an antenna that generates a standing wave of current or voltage (potential) on the radiating element. That is, resonance occurs so that nodes and antinodes of current and voltage (potential) strength are generated on the radiating element. For example, due to the boundary conditions of the current and voltage (potential) on the radiating element, the current becomes 0 at the end of the radiating element, and when connected to the ground, the voltage becomes 0 at the connection with the ground. Typical standing wave antennas include dipole antenna, monopole antenna, inverted L-type antenna, inverted F-type antenna (IFA), one-wavelength loop antenna, folded dipole antenna, folded monopole antenna, microstrip antenna, patch antenna , Plate inverted F type antenna (PIFA), slot antenna, notch antenna, subtypes of each antenna (multiple radiating elements connected in parallel, multiple stubs, radiating element shape changes depending on location, etc.) It is.

Standing wave antenna is used for communication by electromagnetic waves (radio waves). For example, it is used for telephone calls and data communication in mobile phone terminals, wireless LAN communication, satellite signal reception in GPS, and the like.

In each of the embodiments described below, the “magnetic field antenna” is a kind of minute loop antenna and is an antenna that radiates magnetic flux.

Magnetic field type antenna is used for communication by magnetic field coupling. For example, it is used for communication such as NFC (Near field communication).

In the present embodiment, an example of the antenna device 101 including the flat ground conductor 4 inside the substrate 6A has been described, but the present invention is not limited to this configuration. The ground conductor 4 may be formed on the main surface of the substrate 6A. Further, the shape of the ground conductor 4 is not limited to a flat plate, and can be appropriately changed as long as a part of the loop can be formed.

In the present embodiment, an example in which the radiating element 1 and the ground conductor 4 constituting a part of the loop are arranged at different heights (height in the Z direction) is shown, but the present invention is not limited to this configuration. The Z-direction height relationship between the radiating element 1 and the ground conductor 4 is appropriately changed within a range in which the radiating element 1 acting as a standing wave antenna and a loop acting as a magnetic field radiating antenna are provided. Is possible. Note that the directivity of the antenna can be changed by changing the height relationship between the radiating element 1 and the ground conductor 4 in the Z direction.

In the present embodiment, the choke coil L2 is connected near the first end E1 of the radiating element 1, and the capacitor C1 is connected near the second end E2 of the radiating element 1. It is not limited to. If the loop can be configured and the radiating element 1 functions as a standing wave antenna, the position of the connection location (X direction, Y direction) can be changed as appropriate. The capacitor C1 may be connected to the vicinity of the first end E1 of the radiating element 1, and the choke coil L2 may be connected to the vicinity of the second end E2 of the radiating element 1. That is, the arrangement of the reactance element (or circuit) connected near the first end E1 of the radiating element 1 and the reactance element (or circuit) connected near the second end E2 can be switched. . The same applies to other embodiments described below. However, the arrangement of the reactance element (or circuit) connected near the first end E1 of the radiating element 1 and the reactance element (or circuit) connected near the second end E2 of the radiating element 1 was changed. In some cases, the antenna characteristics of the standing wave antenna change.

In the present embodiment, an example in which the radiating element 1 is, for example, a part of the rear housing of a smartphone is shown, but the present invention is not limited to this configuration. The radiating element 1 may have a structure using a conductor provided inside a housing of an electronic device such as a smartphone.

Moreover, although this embodiment disclosed the example in which the feeding coil 3 is disposed inside the loop including the radiating element 1, the ground conductor 4, the choke coil L2, and the capacitor C1, the present invention is not limited to this configuration. . The feeding coil 3 may be disposed outside the loop.

<< Second Embodiment >>
FIG. 5A is a plan view of the antenna device 102 according to the second embodiment, FIG. 5B is a cross-sectional view taken along the line CC in FIG. 5A, and FIG. FIG. 6 is a DD cross-sectional view in FIG. In FIGS. 5A and 5B, the capacitor connected to the feeding coil 3 and the second feeding circuit are not shown for easy understanding of the structure.

The antenna device 102 according to the second embodiment is different from the antenna device 101 in the arrangement of the feeding coil 3. Other configurations are substantially the same as those of the antenna device 101 according to the first embodiment.

The feeding coil 3 of the antenna device 102 is mounted on the other main surface of the substrate 6A (the surface on the back side of the substrate 6A in FIG. 5A). Further, as shown in FIGS. 5B and 5C, the feeding coil 3 is a choke coil mounted on one main surface of the substrate 6A (surface on the front side in FIG. 5A) in plan view. It arrange | positions in the position which overlaps with L2.

Therefore, the feeding coil 3 is magnetically coupled to the choke coil L2 (see the broken line arrow φ2 in FIG. 5B) or electromagnetically coupled.

Even in such a configuration, the feeding coil 3 is magnetically coupled or electromagnetically coupled (magnetic field coupling and electric field coupling) to the loop, and the loop functions as a booster antenna for the feeding coil 3. Therefore, an antenna device having good communication characteristics can be realized with a simple configuration without using a large antenna coil.

As shown in the present embodiment, the feeding coil 3, the second feeding circuit, and the like are not limited to the configuration mounted on one main surface of the substrate 6A (the front side surface in FIG. 5A). Absent. Further, the arrangement of the feeding coil 3 and the second feeding circuit with respect to the substrate 6A can be changed as appropriate within the range of the substrate 6A acting as a magnetic radiation antenna and the range of magnetic coupling or electromagnetic coupling with the choke coil L2. . The positional relationship between the feeding coil 3 and the choke coil L2 is preferably such that the winding axis of the choke coil L2 is positioned along the magnetic path of the feeding coil 3. Thereby, the feeding coil 3 and the choke coil L2 are magnetically coupled or electromagnetically coupled.

<< Third Embodiment >>
FIG. 6 is a plan view of the antenna device 103 according to the third embodiment. In FIG. 6, the capacitor connected to the feeding coil 3 and the second feeding circuit are not shown for easy understanding of the structure.

The antenna device 103 according to the third embodiment is different from the antenna device 101 in the planar shape of the connection conductor 72A connected to the other end of the choke coil L2. Other configurations are substantially the same as those of the antenna device 101 according to the first embodiment.

The connection conductor 72A of the antenna device 103 is an L-shaped conductor pattern formed on one main surface of the substrate 6A and extends in the horizontal direction (X direction in FIG. 6) and the vertical direction (Y direction). The feeding coil 3 is arranged on the connection conductor 72A so that a part thereof overlaps the connection conductor 72A. Note that the coil conductor of the feeding coil 3 is not electrically connected to the connection conductor 72A.

Even in such a configuration, the feeding coil 3 is magnetically coupled or electromagnetically coupled to the loop, and the loop functions as a booster antenna for the feeding coil 3. Therefore, an antenna device having good communication characteristics can be realized with a simple configuration without using a large antenna coil.

Further, the feeding coil 3 of the antenna device 103 is arranged so as to overlap with the connection conductor 72A in a plan view, and the axial direction of the feeding coil 3 is orthogonal to the extending direction (X direction) of the connection conductor 73A. The connecting conductor 72A is magnetically coupled to the feeding coil 3 by the magnetic flux φ3 generated from the feeding coil 3, and is electrically coupled to the feeding coil 3 by the current flowing through the coil conductor of the feeding coil 3. That is, the feeding coil 3 according to the antenna device 103 is magnetically coupled or electromagnetically coupled (magnetic field coupling and electric field coupling) not only with the choke coil L2 but also with the connection conductor 72A.

Furthermore, the feeding coil 3 of the antenna device 103 is disposed in the vicinity of the connection pin 7A that connects the radiation element 1 and the connection conductor 71A in plan view. For this reason, the connection pin 7 A is mainly magnetically coupled to the feeding coil 3 by the magnetic flux generated from the feeding coil 3.

Thus, in the present embodiment, the feeding coil 3 is magnetically coupled or electromagnetically coupled not only to the choke coil L2 but also to the connection conductor 72A and the connection pin 7A that constitute a part of the loop. Therefore, the coupling coefficient between the entire loop and the feeding coil is further increased, and the characteristics of the magnetic field radiation antenna can be improved as a result.

In the antenna device 103 according to the present embodiment, the example in which the feeding coil 3 is coupled to the connection pin 7A has been shown, but the present invention is not limited to this configuration. The connection pin coupled to the feeding coil 3 can be changed as appropriate.

In the antenna device 103 according to the present embodiment, the example in which the feeding coil 3 is coupled to the connection conductor 72A has been shown, but the present invention is not limited to this configuration. The connection conductor coupled to the feeding coil 3 can be changed as appropriate.

Furthermore, in the above-described embodiment, an example in which the feeding coil 3 is coupled to the radiating element 1, the connection pin 7A, or the connection conductor 72A has been described, but the present invention is not limited to this configuration. In the HF band (second frequency band), as long as it is a part of a loop that functions as a booster antenna, the feeding coil 3 may be configured to be magnetically coupled or electromagnetically coupled to other components.

<< Fourth Embodiment >>
FIG. 7 is a plan view of an antenna device 104 according to the fourth embodiment. In FIG. 7, for easy understanding of the structure, the capacitor connected to the feeding coil 3 and the second feeding circuit are not shown.

The antenna device 104 according to the fourth embodiment is different from the antenna device 101 in that it further includes a metal case 9. Other configurations are substantially the same as those of the antenna device 101 according to the first embodiment.

The metal case 9 is a rectangular parallelepiped metal plate molded body in which a metal member is formed in addition to the mounting surface (the surface on the back side of the metal case 9 in FIG. 7), and one main surface of the substrate 6A (the substrate 6A in FIG. 7). Mounted on the front side). The metal case 9 is mounted on one main surface of the substrate 6A so as to cover the periphery of the choke coil L2 and the power feeding coil 3. In other words, the choke coil L 2 and the power feeding coil 3 are housed inside the metal case 9.

With such a configuration, in the HF band (second frequency band), the magnetic field generated by the feeding coil 3 is confined inside the metal case 9, so that the magnetic collecting effect of the choke coil L2 is enhanced. Therefore, the coupling coefficient between the choke coil L2 and the feeding coil 3 is further increased, and the characteristics of the magnetic field radiation antenna can be improved as a result. Further, since the metal case 9 functions as a magnetic shield, it is possible to suppress the choke coil L2 and the power feeding coil 3 from being unnecessarily coupled to external components and the like.

In the present embodiment, an example in which the metal case 9 is a rectangular parallelepiped in which a metal member is formed in addition to the mounting surface is shown, but the present invention is not limited to this configuration. The shape, size, material, and the like of the metal case 9 can be changed as appropriate within a range in which the magnetic field generated by the power feeding coil 3 is confined inside and the effect of collecting magnetism of the choke coil L2 is enhanced.

In the present embodiment, the configuration example in which the metal member is not formed on the entire mounting surface of the metal case 9 is shown, but the present invention is not limited to this configuration. As long as the periphery of the choke coil L2 and the power feeding coil 3 can be covered, a configuration in which an opening is formed in a part of the mounting surface of the metal case 9 may be employed. The shape, size, and the like of the opening can be appropriately changed within a range in which the magnetic field generated by the feeding coil 3 is confined inside and the magnetic flux collecting effect of the choke coil L2 is enhanced.

<< Fifth Embodiment >>
FIG. 8 is an equivalent circuit diagram of the antenna device 105 according to the fifth embodiment using lumped constant elements.

The antenna device 105 according to the fifth embodiment is different from the antenna device 101 in that the antenna device 105 further includes a capacitor C2 connected between the radiating element (inductor L1) and the ground conductor 4. Other configurations are the same as those of the antenna device 101 according to the first embodiment.

As shown in FIG. 8, the capacitor C2 is connected in parallel with the choke coil L2 between the radiating element (inductor L1) and the ground conductor 4. Therefore, a loop including the parallel circuit including the radiating element (inductor L1), the ground conductor 4, the choke coil L2, and the capacitor C2, and the capacitor C1 is configured. The parallel circuit composed of the choke coil L2 and the capacitor C2 is an LC resonance circuit, and the resonance frequency is set so as to be equivalently open in the UHF band or the SHF band (first frequency band).

Even in such a configuration, since the feeding coil is arranged in the vicinity of the choke coil L2, the feeding coil 3 is magnetically coupled or electromagnetically coupled to the choke coil L2 in the HF band (second frequency band). Therefore, the antenna device 105 according to the present embodiment has the same operations and effects as the antenna device 101.

In the present embodiment, the configuration example in which the parallel circuit including the choke coil L2 and the capacitor C2 is connected between the radiating element (inductor L1) and the ground conductor 4 is shown. However, the present embodiment is not limited to this configuration. Absent. A new inductor may be added to form a parallel circuit composed of the inductor and the capacitor C1, or a reactance element may be connected in series to the parallel circuit composed of the choke coil L2 and the capacitor C2. The reactance element connected between the radiating element and the ground conductor 4 is a UHF band or SHF band (first frequency band) where the radiating element acts as a standing wave antenna, and in the HF band (second frequency band). As long as the loop functions as a magnetic field radiation antenna, it can be appropriately changed.

<< Sixth Embodiment >>
FIG. 9 is a plan view of an antenna device 106A according to the sixth embodiment. FIG. 10 is a plan view of an antenna device 106B according to the sixth embodiment. In FIG. 9 and FIG. 10, the capacitor connected to the feeding coil 3 and the second feeding circuit are not shown for easy understanding of the structure.

The antenna device 106A further includes a plurality of

adjacent radiating elements

1A, 1B, a plurality of choke coils L2A, L2B, a plurality of

first feeding circuits

81A, 81B, and

reactance elements

61A, 61B, 62A, 62B. And different. The antenna device 106B is different from the antenna device 101 in that it further includes a plurality of

adjacent radiating elements

1A and 1B and a plurality of choke coils L2A and L2B. Other configurations are substantially the same as those of the antenna device 101 according to the first embodiment.

In the antenna device 106A according to the present embodiment, a plurality of

adjacent radiating elements

1A and 1B, a plurality of choke coils L2 and L2B, a plurality of

first feeding circuits

81A and 81B, and

reactance elements

61A, 61B, 62A, and 62B It is mounted on one main surface of 6A (surface on the front side of substrate 6A in FIG. 9).

The radiating

elements

1A and 1B of the antenna device 106A are flat plates having a rectangular planar shape that coincides with the horizontal direction (X direction in FIG. 9) and having conductivity. The radiating

elements

1A and 1B are shorter in the lateral direction (X direction in FIG. 9) than the radiating element 1 of the antenna device 101. The radiating element 1A and the radiating element 1B are arranged side by side in the horizontal direction across the gap 11A, and are arranged on the same plane. As shown in FIG. 9, the

radiation elements

1A and 1B of the antenna device 106A have substantially the same planar shape. The radiating element 1A has a first end E1 at one end in the longitudinal direction (the right end of the radiating element 1A in FIG. 9), and the radiating element 1B has one end in the longitudinal direction (the radiating element 1B in FIG. 9). The second end portion E2 is provided on the left end portion).

The choke coil L2A is connected between the radiating element 1A and the ground conductor 4. Specifically, one end of the choke coil L2A is connected to the vicinity of the first end E1 of the radiating element 1A via the connection conductor 71A and the connection pin 7, and the other end of the choke coil L2A is connected to the connection conductor 72A and the interlayer connection. It is connected to the ground conductor 4 through a conductor (not shown).

The choke coil L2B is connected between the

adjacent radiating elements

1A and 1B. Specifically, one end of the choke coil L2B is connected to the radiating element 1A via the connecting conductor 75A and the connecting pin 7, and the other end of the choke coil L2B is connected to the radiating element 1B via the connecting conductor 76A and the connecting pin 7. Connected to.

The capacitor C1 is connected between the radiating element 1B and the ground conductor 4. Specifically, one end of the capacitor C1 is connected to the vicinity of the second end E2 of the radiating element 1B via the connection conductor 73A and the connection pin 7, and the other end of the capacitor C1 is connected to the connection conductor 74A and the interlayer connection conductor ( It is connected to the ground conductor 4 via a not shown).

Therefore, as shown in FIG. 9, one loop including the radiating

elements

1A and 1B, the ground conductor 4, the choke coils L2A and L2B, and the capacitor C1 is formed.

The feeding coil 3 according to the antenna device 106A is arranged at a position where the coil opening is along the edge of the radiating element 1A and the radiating element 1B in a plan view. That is, the coil opening of the feeding coil 3 is arranged so as to face the radiating element 1A and the radiating element 1B in plan view. Therefore, the feeding coil 3 is magnetically coupled or electromagnetically coupled to the radiating element 1A and the radiating element 1B. The feeding coil 3 is disposed in the vicinity of the choke coil L2B. Therefore, the feeding coil 3 is magnetically coupled or electromagnetically coupled to the choke coil L2B in the HF band (second frequency band).

Thus, the feeding coil 3 of the antenna device 106A is magnetically or electromagnetically coupled to the loop including the radiating

elements

1A and 1B, the ground conductor 4, the choke coils L2A and L2B, and the capacitor C1.

The input / output part of the first power supply circuit 81A is connected to the vicinity of the first end E1 in the longitudinal direction of the radiating element 1A via the connection conductor, the connection pin 7 and the reactance element 61A formed on one main surface of the substrate 6A. Is done. The connecting portion between the radiating element 1A including the reactance element 62A and the ground is a stub provided for matching the antenna including the radiating element 1A and the first feeding circuit 81A. The reactance element 62A is provided on one main surface of the substrate 6A. It is connected to the vicinity of the first end E1 of the radiating element 1A via the formed connection conductor and connection pin 7. The first power supply circuit 81A is, for example, a power supply circuit of a 2.4 GHz band wireless LAN communication system.

The first power supply circuit 81B is an IC for UHF band or SHF band (first frequency band). The input / output part of the first power supply circuit 81B is connected to the vicinity of the second end E2 in the longitudinal direction of the radiating element 1B via the connection conductor, the connection pin 7 and the reactance element 61B formed on one main surface of the substrate 6A. Is done. The connecting portion between the radiating element 1B including the reactance element 62B and the ground is a stub provided for matching the antenna including the radiating element 1B and the first feeding circuit 81B. The reactance element 62B is provided on one main surface of the substrate 6A. It is connected to the vicinity of the second end E2 of the radiating element 1B via the formed connection conductor and connection pin 7. The first power supply circuit 81B is, for example, a power supply circuit of a communication system for GPS in the 1.5 GHz band.

Note that it is preferable that the choke coil L2B of the antenna device 106A is equivalently open in one of two different frequency bands (both being the first frequency band in the present invention). For example, a choke coil L2B that has a high impedance in the 2.4 GHz band (wireless LAN) and is equivalently open is connected between the radiating

elements

1A and 1B. With this configuration, in the 2.4 GHz band (wireless LAN), the radiating element 1A acts as a radiating element of the standing wave antenna, and in the 1.5 GHz band (for GPS), the radiating element 1A and the radiating element 1B are standing wave type. Acts as a radiating element for the antenna. Thus, by using a plurality of

adjacent radiating elements

1A and 1B as standing wave antennas, it is possible to realize an antenna device adapted to a system using two different frequency bands (both being the first frequency band).

In the antenna device 106B according to the present embodiment, a plurality of

adjacent radiating elements

1A and 1B and a plurality of choke coils L2 and L2B are mounted on one main surface of the substrate 6A (the surface on the front side of the substrate 6A in FIG. 10). .

The

radiation elements

1A and 1B of the antenna device 106B are flat plates having a rectangular planar shape and conductivity. As with the antenna device 106A, the radiating

elements

1A and 1B are arranged side by side in the horizontal direction with the gap 11A interposed therebetween, and are arranged on the same plane. As shown in FIG. 10, the radiating

elements

1A and 1B of the antenna device 106B have different lengths in the horizontal direction (X direction in FIG. 10). The radiating element 1A has a first end E1 at one end (the right end of the radiating element 1A in FIG. 10), and the radiating element 1B has one end (the left end of the radiating element 1B in FIG. 10). Has a second end E2.

The basic configuration of the choke coil L2A, choke coil L2B and capacitor C1 of the antenna device 106B is the same as that of the antenna device 106A. Therefore, as shown in FIG. 10, a loop including the radiating

elements

1A and 1B, the ground conductor 4, the choke coils L2A and L2B, and the capacitor C1 is configured.

The feeding coil 3 of the antenna device 106B is disposed between the radiating element 1A and the ground conductor 4 in a plan view and at a position where the coil opening is along the edge of the radiating element 1A. That is, the coil opening of the feeding coil 3 is arranged so as to face the radiating element 1A in plan view. Therefore, the feeding coil 3 is magnetically coupled or electromagnetically coupled to the radiating element 1A.

Further, the feeding coil 3 of the antenna device 106B is disposed in the vicinity of the choke coils L2A and L2B. Therefore, the feeding coil 3 is magnetically coupled (see the broken arrows φ4 and φ5 in FIG. 10) or electromagnetically coupled to the choke coils L2A and L2B in the HF band (second frequency band).

Thus, the feeding coil 3 of the antenna device 106B is magnetically or electromagnetically coupled to the loop including the radiating

elements

Even in such a configuration, the basic configuration of the

antenna devices

106A and 106B is the same as that of the antenna device 101 according to the first embodiment, and has the same operations and effects as the antenna device 101.

Further, as shown by the antenna device 106B, the coupling coefficient is further increased by coupling the feeding coil 3 with the plurality of choke coils L2A and L2B constituting a part of the loop, thereby further increasing the coupling coefficient. As a result, the characteristics can be improved.

In the present embodiment, the example of the

antenna devices

106A and 106B in which the

radiating elements

1A and 1B are arranged on the same plane (the same height in the Z direction) is shown, but the present invention is not limited to this configuration. . The height relationship in the Z direction of the radiating

elements

1A and 1B is appropriately determined within a range in which the

radiating elements

1A and 1B acting as a standing wave antenna and a loop portion acting as a magnetic field radiating antenna are provided. It can be changed. Note that the directivity of the antenna can be changed by changing the height relationship of the radiating

elements

1A and 1B in the Z direction.

In the present embodiment, an example in which the planar shape of the plurality of

adjacent radiating elements

1A and 1B is a rectangle is shown, but the present invention is not limited to this configuration. The planar shapes of a plurality of adjacent radiating elements can be appropriately changed within a range that forms a part of the loop and acts as a standing wave antenna in the UHF band or the SHF band (first frequency band).

In addition, in the

antenna devices

106A and 106B according to the present embodiment, the configuration example including the two

adjacent radiating elements

1A and 1B is shown, but the configuration is not limited to this configuration. The configuration may include three or more adjacent radiating elements.

When three or more adjacent radiating elements and first feeding circuits are provided, the choke coils respectively connected between the adjacent radiating elements have different frequency bands (both are the first frequency band in the present invention). ) Is preferably equivalently open. For example, a choke coil L2B that includes three

adjacent radiating elements

1A, 1B, and 1C and is equivalently open in the 2.4 GHz band (wireless LAN) is connected between the radiating

elements

1A and 1B, and the 5 GHz band. A choke coil L2C that is equivalently opened in (wireless LAN) is connected between the radiating elements 1B and 1C. With this configuration, the radiating

elements

1A, 1B, and 1C function as the radiating elements of the standing wave antenna in the 1.5 GHz band (for GPS), and the radiating element 1A in the 2.4 GHz band (wireless LAN). The radiating element 1C functions as a radiating element of the standing wave antenna in the 5 GHz band (wireless LAN). In this way, by using a plurality of (three or more) adjacent radiating elements as standing wave antennas, it is applicable to a system using a plurality (three or more) of different frequency bands (all of which are the first frequency band). An antenna device can be realized.

In this embodiment, an example in which the choke coil is independently connected in series between adjacent radiating elements is shown, but the present invention is not limited to this configuration. A parallel resonance circuit, a series resonance circuit, a filter, or the like is connected between adjacent radiating elements, and a feeding coil may be coupled to a choke coil that constitutes the resonance circuit or the filter.

<< Seventh Embodiment >>
FIG. 11A is a plan view of the antenna device 107 according to the seventh embodiment, FIG. 11B is a cross-sectional view taken along line EE in FIG. 11A, and FIG. FIG. 12 is a sectional view taken along line FF in FIG. FIG. 12 is an equivalent circuit diagram of the antenna device 107 using lumped constant elements. In FIG. 12, the conductor plate 5 is represented by an inductor L5.

The antenna device 107 according to the seventh embodiment is different from the antenna device 101 in that it further includes a conductor plate 5. Other configurations are the same as those of the antenna device 101 according to the first embodiment.

Hereinafter, parts different from the antenna device 101 according to the first embodiment will be described.

The conductor plate 5 is a flat plate having a rectangular planar shape and having conductivity. The radiating element 1 and the conductor plate 5 according to the present embodiment are arranged side by side in the vertical direction (Y direction in FIG. 11A) with the gap 11 therebetween, and are arranged on the same plane (FIG. 11). (See (B)). The longitudinal direction of the conductor plate 5 coincides with the vertical direction (Y direction in FIG. 11A).

The other end of the choke coil L2 is connected to the conductor plate 5 via the connection conductor 72A and the connection pin 7. The other end of the capacitor C1 is connected to the conductor plate 5 via the connection conductor 74A and the connection pin 7.

Therefore, as shown in FIGS. 11A and 12, a loop including the radiating element 1, the conductor plate 5, the choke coil L2, and the capacitor C1 is formed.

The feeding coil 3 is arranged between the radiating element 1 and the conductor plate 5 in a plan view and at a position where the coil opening is along the edge of the radiating element 1. That is, the coil opening of the feeding coil 3 is arranged so as to face the radiating element 1 and the conductor plate 5 in plan view. Therefore, the feeding coil 3 is mainly magnetically coupled to the radiating element 1 and the conductor plate 5. In addition to magnetic field coupling, electromagnetic field coupling is performed by electric field coupling. The feeding coil 3 is disposed in the vicinity of the choke coil L2. Therefore, the feeding coil 3 is magnetically coupled or electromagnetically coupled to the choke coil L2 in the HF band (second frequency band).

As described above, the feeding coil 3 is magnetically or electromagnetically coupled to the loop including the radiating element 1, the conductor plate 5, the choke coil L2, and the capacitor C1 in the HF band (second frequency band).

Even in such a configuration, the basic configuration of the antenna device 107 is the same as that of the antenna device 101 according to the first embodiment, and the same operations and effects as the antenna device 101 are achieved.

The conductor plate 5 may be configured to be grounded. In this case, a method of connecting to the ground of the substrate 6A via, for example, a movable probe pin can be considered as the grounding method. However, the grounding method is not limited to this and can be arbitrarily changed. Further, the position and number of grounding points can be arbitrarily changed. The conductor plate 5 is preferably grounded via a reactance circuit having high impedance in the HF band (second frequency band) and low impedance in the UHF band or SHF band (first frequency band). With this configuration, in the HF band (second frequency band), since the conductor plate 5 is separated from the ground, the influence of the loop from the ground can be suppressed.

<< Eighth Embodiment >>
13A is a plan view of the antenna device 108 according to the eighth embodiment, FIG. 13B is a cross-sectional view taken along the line GG in FIG. 13A, and FIG. FIG. 14 is a cross-sectional view taken along line HH in FIG.

The antenna device 108 according to the eighth embodiment is different from the antenna device 101 in that the first feeding circuit 81 and the reactance element 62 are connected to the conductor plate 5. Other configurations are the same as those of the antenna device 101 according to the first embodiment.

One end of the input / output unit of the first power feeding circuit 81 is near the second end E2 in the longitudinal direction of the radiating element 1 via the connection conductor, the connection pin 7 and the reactance element 61 formed on one main surface of the substrate 6A. Connected to. The other end of the input / output unit of the first power supply circuit 81 is connected to the conductor plate 5 via a connection conductor and a connection pin 7 formed on one main surface of the substrate 6A.

The reactance element 62 is connected between the radiating element 1 and the conductor plate 5 via a connection conductor and a connection pin 7 formed on one main surface of the substrate 6A. The reactance element 62 is a stub provided for matching between the antenna including the radiating element 1 and the first feeding circuit 81, and is connected near the second end E 2 of the radiating element 1.

Even in such a configuration, the basic configuration of the antenna device 108 is the same as that of the antenna device 101 according to the first embodiment, and the same operations and effects as the antenna device 101 are achieved.

In the antenna device 108 according to the present embodiment, the first feeding circuit 81 is connected between the radiating element 1 and the conductor plate 5. Therefore, in the UHF band or the SHF band (first frequency band), the radiating element 1 and the conductor plate 5 act as a dipole antenna that contributes to electromagnetic radiation. Thus, the radiating element 1 and the conductor plate 5 can be used as the radiating element of the standing wave antenna.

<< Ninth embodiment >>
FIG. 14A is a plan view of the antenna device 109 according to the ninth embodiment, and FIG. 14B is a cross-sectional view taken along the line II in FIG.

The antenna device 109 according to the ninth embodiment is different from the antenna device 101 according to the first embodiment in that the radiation conductor 10 formed on the substrate 6A is used as a radiation element. Other configurations are substantially the same as those of the antenna device 101.

The radiation conductor 10 is a C-shaped conductor pattern in plan view, and is formed on one main surface of the substrate 6A (surface on the front side in FIG. 14A). In the present embodiment, the radiation conductor 10 corresponds to a “radiation element” according to the present invention.

The choke coil L2 is connected between the radiation conductor 10 and the conductor plate 5. Specifically, one end of the choke coil L2 is directly connected to the radiation conductor 10. The other end of the choke coil L2 is connected to the conductor plate 5 via the connection conductor 72A and the connection pin 7.

The capacitor C1 is connected between the radiation conductor 10 and the conductor plate 5 via the connection conductor 74A and the connection pin 7 formed on one main surface of the substrate 6A.

Therefore, as shown in FIG. 14, a loop including the radiation conductor 10, the conductor plate 5, the choke coil L2, and the capacitor C1 is formed.

Even in such a configuration, the basic configuration of the antenna device 109 is the same as that of the antenna device 101 according to the first embodiment, and the same operations and effects as the antenna device 101 are achieved. In the antenna device 109 according to the present embodiment, it is preferable that there is no metal casing around the radiation conductor 10 so as not to prevent the formation of magnetic flux.

In the present embodiment, since the planar shape of the radiation conductor 10 is C-shaped, the effective coil opening of the loop acting as a magnetic field radiation type antenna is large in the HF band (second frequency band). Therefore, the range and distance for radiating (collecting) magnetic flux is large, and it is easy to couple with the antenna coil on the communication partner side. Furthermore, since the radiating conductor 10 acts as a standing wave antenna in the UHF band or the SHF band (first frequency band), it is preferable to design the width and length.

In the present embodiment, an example in which the planar shape of the radiation conductor 10 is a C-shape has been shown, but the present invention is not limited to this configuration. The planar shape of the radiation conductor 10 can be changed as appropriate within a range having the above functions, such as a rectangular shape, a polygonal shape, a circular shape, or an elliptical shape.

Further, in the antenna device 109 according to the present embodiment, an existing conductor pattern formed on one main surface of the substrate 6A can be used as a part of the antenna (radiation conductor 10). Thereby, it is not necessary to separately form a radiating element, and manufacturing is easy and cost reduction can be achieved.

Note that the reactance element 62 in the present embodiment is not limited to a chip capacitor. The reactance element 62 may be composed of an open stub or a short stub formed on the substrate 6A. Further, the reactance element 62 may be composed of a plurality of open stubs or short stubs.

<< Tenth Embodiment >>
FIG. 15A is a plan view of the antenna device 110 according to the tenth embodiment, and FIG. 15B is a JJ cross-sectional view in FIG. 15A.

The antenna device 110 according to the tenth embodiment is different from the antenna device 107 according to the seventh embodiment in that the radiating element 1B, the choke coil L2B, the feeding coil 3B, the capacitor C1B, the first feeding circuit 81B, and the second feeding. The difference is that a circuit 82B,

reactance elements

61B and 62B, and capacitors C41B, C42B, C43B, and C44B are further provided. Other configurations are substantially the same as those of the antenna device 107 according to the seventh embodiment. In other words, it can be said that the configuration includes two antenna devices 107 that are vertically symmetrical in the short side direction (Y direction in FIG. 15A) of the substrate 6A.

Hereinafter, parts different from the antenna device 107 according to the seventh embodiment will be described.

Choke coil L2B, capacitor C1B, first power supply circuit 81B, second power supply circuit 82B,

reactance elements

61B and 62B, and capacitors C41B to C44B are mounted on one main surface of substrate 6B (the front surface in FIG. 15A). Is done.

The radiating element 1B is a flat plate having a rectangular planar shape and conductivity. The conductor plate 5 according to the present embodiment has a shorter length in the vertical direction (Y direction in FIG. 15A) than the conductor plate 5 of the antenna device 107. The radiating element 1B and the conductor plate 5 are arranged side by side in the vertical direction with the gap 11B interposed therebetween, and are arranged on the same plane (see FIG. 15B). The radiating element 1B has a longitudinal direction that coincides with the lateral direction (the X direction in FIG. 15A), and has a first end E1B and a second end E2B at both ends in the longitudinal direction.

One end of the choke coil L2B is connected to the vicinity of the first end E1B in the longitudinal direction of the radiating element 1B via a connection conductor 71B and a connection pin 7 formed on one main surface of the substrate 6B. The other end of the choke coil L2B is connected to the conductor plate 5 via a connection conductor 72B and a connection pin 7 formed on one main surface of the substrate 6B.

One end of the capacitor C1B is connected to the vicinity of the second end E2B in the longitudinal direction of the radiating element 1B via a connection conductor 73B and a connection pin 7 formed on one main surface of the substrate 6B. The other end of the capacitor C1B is connected to the conductor plate 5 via a connection conductor 74B and a connection pin 7 formed on one main surface of the substrate 6B.

Therefore, as shown in FIG. 15A, another loop including the radiating element 1B, the conductor plate 5, the choke coil L2B, and the capacitor C1B is configured.

The first power supply circuit 81B is an IC for UHF band or SHF band (first frequency band). The input / output part of the first power supply circuit 81B is connected to the vicinity of the second end E2B in the longitudinal direction of the radiating element 1B via the connection conductor, the connection pin 7 and the reactance element 61B formed on one main surface of the substrate 6B. Is done. The first power supply circuit 81B is, for example, a power supply circuit of a communication system for GPS in the 1.5 GHz band.

The reactance element 62B is an element provided for matching of the first power feeding circuit 81B with respect to another communication system. The reactance element 62B is connected to the radiation element 1B via the connection conductor and the connection pin 7 formed on one main surface of the substrate 6B. It is connected in the vicinity of the second end E2B in the longitudinal direction.

In this way, in the UHF band or the SHF band (first frequency band), the radiating element 1B acts as a standing wave inverted F-type antenna that contributes to electromagnetic wave radiation, and resonates to determine the current intensity and voltage intensity. A standing wave occurs.

The second power supply circuit 82B is a balanced input / output HF band (second frequency band) IC. The power feeding coil 3B is connected to the input / output portion of the second power feeding circuit 82B via capacitors C41B to C44B. A series circuit of capacitors C41B and C42B is connected in parallel to the feeding coil 3B, thereby forming an LC resonance circuit. The second power feeding circuit 82B feeds an HF band communication signal to the LC resonance circuit via the capacitors C43B and C44B. The second power supply circuit 82B is, for example, an RFID RFIC element of 13.56 MHz, and the power supply coil 3B is, for example, a laminated ferrite chip antenna in which a coil conductor is wound around a magnetic ferrite core.

The feeding coil 3B is magnetically or electromagnetically coupled to a loop including the radiating element 1B, the conductor plate 5, the choke coil L2B, and the capacitor C1B.

Specifically, the feeding coil 3 B is disposed between the radiating element 1 B and the conductor plate 5 in a plan view and at a position where the coil opening is along the edge of the radiating element 1 B and the conductor plate 5. . That is, the coil opening of the feeding coil 3 is arranged so as to face the radiating element 1 B and the conductor plate 5 in plan view. Therefore, the feeding coil 3B is magnetically coupled or electromagnetically coupled to the radiating element 1B and the conductor plate 5.

The feeding coil 3B is disposed in the vicinity of the first end E1 of the radiating element 1B in plan view. That is, the feeding coil 3B is disposed in the vicinity of the choke coil L2B. Therefore, in the HF band (second frequency band), the feeding coil 3B is magnetically or electromagnetically coupled to the choke coil L2B having a large inductance ratio with respect to the inductance of the entire loop.

With this configuration, it is possible to realize a communication terminal device provided with two antenna devices in the vertical direction (Y direction in FIG. 15A) that can be shared by a plurality of systems having different frequency bands.

In antenna device 110 according to the present embodiment, as shown in FIG. 15A, in a plan view, radiating element 1, conductor plate 5, and radiating element 1B are arranged side by side in the vertical direction (Y direction). However, the present invention is not limited to this configuration. About arrangement | positioning of the radiation element 1, the conductor plate 5, and the radiation element 1B, it can change suitably.

In the antenna device 110 according to the present embodiment, the example in which the two radiating

elements

1 and 1B are provided has been described, but the configuration is not limited to this. The number of radiating elements can be changed as appropriate.

<< Eleventh Embodiment >>
FIG. 16A is a plan view of the antenna device 111 according to the eleventh embodiment, and FIG. 16B is a cross-sectional view taken along the line KK in FIG.

The antenna device 111 according to the eleventh embodiment further includes a radiating element 1B, a choke coil L2B, a capacitor C1B, a first feeder circuit 81B, and

reactance elements

61B and 62B, compared to the antenna device 107 according to the seventh embodiment. It differs in the point to prepare. Other configurations are substantially the same as those of the antenna device 107 according to the seventh embodiment.

The choke coil L2B, the capacitor C1B, the first power supply circuit 81B, and the

reactance elements

61B and 62B are mounted on one main surface (surface on the front side in FIG. 16A) of the substrate 6B.

The radiating element 1B is a flat plate having a rectangular planar shape and conductivity. The conductor plate 5 according to the present embodiment is shorter in the vertical direction (Y direction in FIG. 16A) than the conductor plate 5 of the antenna device 107. The radiating element 1B and the conductor plate 5 are arranged side by side in the vertical direction with the gap 11B interposed therebetween, and are arranged on the same plane (see FIG. 16B). The radiating element 1B has a longitudinal direction coinciding with a lateral direction (X direction in FIG. 16A), and has a first end E1B and a second end E2B at both ends in the longitudinal direction.

In the antenna device 111 of the present embodiment, as shown in FIG. 16A, a large loop including the radiating

elements

1 and 1B, the conductor plate 5, the choke coils L2 and L2B, and the capacitors C1 and C1B is configured.

The feeding coil 3 is magnetically or electromagnetically coupled to a large loop including the radiating

elements

1 and 1B, the conductor plate 5, the choke coils L2 and L2B, and the capacitors C1 and C1B.

This configuration further increases the effective coil opening functioning as an antenna and increases the range and distance for radiating (collecting) magnetic flux, thereby facilitating coupling with the antenna coil on the communication partner side. Therefore, an antenna device with better communication characteristics can be realized without using a large antenna coil.

In the present embodiment, the example of the antenna device 107 in which the radiating element 1 and the conductor plate 5 are arranged on the same plane (the height in the Z direction is the same) is shown, but the present invention is not limited to this configuration. . The height relationship in the Z direction between the radiating element 1 and the conductor plate 5 is appropriately determined within a range in which the radiating element 1 acting as a standing wave antenna and a loop portion acting as a magnetic field radiating antenna are provided. It can be changed. Note that the directivity of the antenna can be changed by changing the height relationship in the Z direction between the radiating element 1 and the conductor plate 5.

<< Twelfth Embodiment >>
FIG. 17 is a cross-sectional view of the antenna device 112 according to the twelfth embodiment.

The antenna device 112 according to the twelfth embodiment is different from the antenna device 107 according to the seventh embodiment in that no connection pin is provided. Other configurations are substantially the same as those of the antenna device 107 according to the seventh embodiment.

The antenna device 112 includes

conductive connection portions

91 and 92 and a screw member 93 as an alternative to the connection pins. The

conductive connection portions

91 and 92 are bent portions of the radiating element 1 and the conductor plate 5. The conductive connection portion 91 is fixed to the substrate 6 A via a screw member 93. As shown in FIG. 17, the radiating element 1 is connected to one end of the choke coil L2 via the conductive connecting

portions

91 and 71A. The conductive connection portion 92 is fixed to the substrate 6 A via a screw member 93. As shown in FIG. 17, the conductor plate 5 is connected to the other end of the choke coil L2 via the conductive connecting

portions

92 and 72A.

As described above, in the antenna device according to the above-described embodiment, the portion connected via the connection pin can be connected by the conductive connection portion 91 and the screw member 93. In the present embodiment, the example in which the shapes of the

conductive connection portions

91 and 92 are the bent portions of the radiating element 1 and the conductor plate 5 has been described, but the present invention is not limited to this configuration. The

conductive connection portions

91 and 92 may be members having conductivity different from those of the radiating element 1 and the conductor plate 5. In that case, the

conductive connection portions

91 and 92 may be connected to the radiating element 1 and the conductor plate 5 using a screw member, or connected to the radiating element 1 and the conductor plate 5 via a conductive adhesive. May be.

In the present embodiment, the example in which the

conductive connection portions

91 and 92 are fixed to the substrate 6A via the screw member 93 is shown, but the present invention is not limited to this configuration. The structure which fixes the

electroconductive connection parts

91 and 92 to the board | substrate 6A via an electroconductive adhesive material without using the screw member 93 may be sufficient.

Furthermore, even if it is the structure which connects the conductor pattern formed in the flexible printed circuit board, and the connection conductor formed in the board | substrate 6A by fixing a flexible printed circuit board to the board | substrate 6A, without using the

connection conductors

71A and 72A. Good.

<< Thirteenth embodiment >>
FIG. 18A is a cross-sectional view of the antenna device 113A according to the thirteenth embodiment, and FIG. 18B is a cross-sectional view of the antenna device 113B.

The

antenna devices

113A and 113B according to the thirteenth embodiment differ from the antenna device 107 according to the seventh embodiment in that the choke coil L2 is not mounted on the substrate 6A. Other configurations are substantially the same as those of the antenna device 107 according to the seventh embodiment.

The antenna device 113A further includes

conductive connection portions

91 and 92, a screw member 93, and a wiring board 70. A conductor pattern (not shown) is formed on the first main surface (upper surface in FIG. 18A) of the wiring board 70. The wiring board 70 is, for example, a flexible printed circuit (Flexible printed circuit).

The choke coil L2 is mounted on the first main surface of the wiring board 70. The conductive connection portion 91 is a bent portion of the radiating element 1 and is fixed to the wiring board 70 via a screw member 93. The conductive connection portion 92 is a bent portion of the conductor plate 5 and is fixed to the wiring board 70 via a screw member 93. The radiating element 1 and the conductor plate 5 are connected to the choke coil L 2 via a conductor pattern formed on the first main surface of the wiring substrate 70 and the

conductive connection portions

91 and 92.

The antenna device 113B further includes

conductive adhesives

94 and 95 and a wiring board 70. A conductive pattern (not shown) is formed on the wiring board 70.

The choke coil L2 is mounted on the second main surface (the lower surface in FIG. 18B) of the wiring board 70. The radiating element 1 is connected to one end of the choke coil L2 through a conductor pattern formed on the wiring board 70, a conductive adhesive 94, and the like. The conductor plate 5 is connected to the other end of the choke coil L2 via a conductor pattern formed on the wiring board 70, a conductive adhesive 95, and the like. Components other than the choke coil L2 can be similarly mounted on the wiring board 70.

With this configuration, it is not necessary to connect the radiating element 1 and the substrate 6A, and it is not necessary to connect the conductor plate 5 and the substrate 6A.

Further, in the

antenna devices

113A and 113B according to the present embodiment, since components such as the choke coil L2 can be mounted on the wiring substrate 70, the mounting space on the substrate 6A is expanded, and the degree of freedom in the arrangement of the mounted components is increased. Can be increased.

Furthermore, in the antenna device 113A according to the present embodiment, the example in which the wiring board 70 is fixed to the

conductive connection portions

91 and 92 via the screw member 93 is shown, but the present invention is not limited to this configuration. As shown in the antenna device 113B, the configuration may be such that the wiring board 70 is fixed via a conductive adhesive without using the screw member 93.

<< Fourteenth embodiment >>
FIG. 19 is a plan view of an antenna device 114 according to the fourteenth embodiment. In FIG. 19, a choke coil, a feeding coil, a capacitor, a first feeding circuit, a second feeding circuit, a reactance element, and the like are not shown.

The antenna device 114 according to the fourteenth embodiment is different from the antenna device 107 according to the seventh embodiment in that it further includes

openings

96 and 97. Other configurations are substantially the same as those of the antenna device 107 according to the seventh embodiment.

The radiating element 1 according to the antenna device 114 includes an opening 96, and the conductor plate 5 includes an opening 97. The

openings

96 and 97 are, for example, an opening for a camera module or an opening for a button.

Even in such a configuration, the basic configuration of the antenna device 114 is the same as that of the antenna device 107 according to the seventh embodiment, and the same operations and effects as the antenna device 107 are achieved.

It should be noted that the positions, sizes, number, etc. of the

openings

96, 97 shown in the present embodiment are merely examples, and are not limited to this configuration. The position, size, number, and the like of the

openings

96 and 97 can be changed as appropriate as long as the radiating element 1 and the conductor plate 5 form a loop and function as a booster antenna.

In the present embodiment, the example in which the radiating element 1 and the conductor plate 5 constitute a part of the loop is shown, but the present invention is not limited to this configuration. The ground conductor may include an opening, and the radiating element 1 and the ground conductor may form part of the loop. In that case, the position, size, number, and the like of the openings provided in the ground conductor can be changed as appropriate as long as the radiating element 1 and the ground conductor form a loop and function as a booster antenna. Further, in the

openings

96 and 97, a device such as a speaker or a sensor, or a resin shaped like an emblem may be disposed.

<< 15th Embodiment >>
FIG. 20 is an external perspective view showing the radiating element 1D and the conductor plate 5D in the antenna device 115A according to the fifteenth embodiment. FIG. 21 is an external perspective view showing the radiating element 1E and the conductor plate 5E in the antenna device 115B. FIG. 22 is an external perspective view showing the radiation element 1F and the conductor plate 5F in the antenna device 115C. FIG. 23 is an external perspective view showing the radiating element 1G and the conductor plate 5G in the antenna device 115D. In FIG. 20, FIG. 21, FIG. 22, and FIG. 23, the choke coil, the feeding coil, the substrate, the battery pack, the capacitor, the first feeding circuit, the second feeding circuit, the reactance element, and the like are omitted.

The

antenna devices

115A, 115B, 115C, and 115D differ from the antenna device 107 according to the seventh embodiment in the shapes of the radiating elements and the conductor plates, and the other configurations are the antenna devices 107 according to the seventh embodiment. Is substantially the same.

The radiating element 1D according to the antenna device 115A is not formed in a flat plate, but is also formed and connected to both sides in the horizontal direction (X direction in FIG. 20) and one side surface in the vertical direction (Y direction) (right side in FIG. 20). . The conductor plate 5D according to the antenna device 115A is not a flat plate, but is also formed and connected to the side surfaces at both ends in the lateral direction (X direction). As shown in FIG. 20, the conductor plate 5D is a U-shaped conductor as viewed from the Y direction.

The radiating element 1E according to the antenna device 115B is not formed in a flat plate, but is also formed and connected to side surfaces at both ends in the lateral direction (X direction in FIG. 21). As shown in FIG. 21, the radiating element 1E is a U-shaped (U-shaped) conductor as viewed from the Y direction. The conductor plate 5E according to the antenna device 115B has substantially the same shape as the conductor plate 5D according to the antenna device 115A.

The radiating element 1F according to the antenna device 115C is not a flat plate, but is formed and connected to both sides in the horizontal direction (X direction in FIG. 22) and side surfaces in one end (right side in FIG. 22) in the vertical direction (Y direction). As shown in FIG. 22, the radiating element 1E is a U-shaped (U-shaped) conductor as viewed from the Z direction. The conductor plate 5F according to the antenna device 115C has substantially the same shape as the conductor plate 5D according to the antenna device 115A.

The radiating element 1G according to the antenna device 115D is not formed in a flat plate but is also formed and connected to a side surface of one end (right side in FIG. 23) in the vertical direction (Y direction). As shown in FIG. 23, the radiating element 1G is an L-shaped conductor as viewed from the X direction. The conductor plate 5G according to the antenna device 115D is not a flat plate, but is also formed and connected to both sides in the lateral direction (X direction) and the other side in the longitudinal direction (Y direction) (left side in FIG. 23).

As shown in the present embodiment, the shapes of the radiating element 1 and the conductor plate can be changed as appropriate, such as a planar shape and a three-dimensional structure, as long as they constitute part of the loop and function as a booster antenna. Further, as shown in the present embodiment, the radiating element and the conductor plate are not limited to flat plates. The thickness of the radiating element and the conductor plate (the length in the Z direction) can be appropriately changed within a range that forms part of the loop and functions as a booster antenna.

In this embodiment, an example of an antenna device including a loop including a radiating element and a conductor plate is shown, but the same applies to an antenna device including a loop including a radiating element and a ground conductor. That is, the shape of the ground conductor can also be changed as appropriate, such as a planar shape and a three-dimensional structure, as long as it forms part of the loop and functions as a booster antenna. Further, the ground conductor is not limited to a flat plate, and the thickness (the length in the Z direction) of the ground conductor can be appropriately changed as long as it constitutes a part of the loop and functions as a booster antenna.

<< Other Embodiments >>
In the above-described embodiment, the example in which the planar shape of the radiating element 1, the conductor plate 5, or the ground conductor 4 is rectangular has been described, but the present invention is not limited to this configuration. The radiating element 1, the ground conductor 4, or the conductor plate 5 may have a curved shape or a linear shape. The shapes of the radiating element 1 and the ground conductor 4 or the conductor plate 5 can be appropriately changed within a range that constitutes a part of the loop and functions as a booster antenna.

In the above-described embodiment, an example is shown in which the loop portion acts as a magnetic field radiation type antenna that contributes to magnetic field radiation for near-field communication in the HF band (second frequency band), but is limited to this configuration. It is not a thing. The loop portion can also be used as a power receiving antenna or a power transmitting antenna in a non-contact power transmission system using at least magnetic field coupling such as an electromagnetic induction method or a magnetic field resonance method. When the antenna device of the above-described embodiment is used for a power transmission device, the loop unit is a power transmission antenna, and the second power feeding circuit is a power transmission circuit that supplies power to the power transmission antenna. When the antenna device described above is used as a power receiving device, the loop unit serves as a power receiving antenna, and the second power feeding circuit serves as a power receiving circuit that supplies power received by the power receiving antenna to a load in the power receiving device.

C1, C1B, C2, C41, C41B, C42, C42B, C43, C43B, C44, C44B ... Capacitors E1, E1B ... First end E2, E2B ... Second end L2, L2A, L2B ... Choke coils M13, M23 ... Mutual inductance OP ... Open end SP ...

Ground end

1, 1A, 1B, 1C, 1D, 1E, 1F, 1G ...

Radiation element

3, 3B ... Feed coil 4 ...

Ground conductor

5, 5D, 5E, 5F, 5G ...

Conductor Plate

6A, 6B ...

Substrate

7, 7A ... Connection pin 8 ... Battery pack 9 ... Metal case 10 ...

Radiation conductor

11, 11A, 11B ... Gap 52A ...

Interlayer connection conductor

61, 61A, 61B, 62, 62A, 62B ... Reactance Element 70 ...

Wiring boards

71A, 71B, 72A, 72B, 73A, 73B, 74A, 74B, 75A, 76A ...

Connection conductors

81, 81 , 81B... First feeding

circuit

82, 82B.

Second feeding circuit

91, 92... Conductive connection 93...

Screw member

94, 95.

Adhesive

96, 97.

Opening

100, 101, 102, 103, 104, 105 106A, 106B, 107, 108, 109, 110, 111, 112, 113A, 113B, 114, 115A, 115B, 115C, 115D...

Claims

A radiating element of a standing wave antenna having conductivity and connected to the first feeding circuit for the first frequency band;
A feeding coil connected to the second feeding circuit for the second frequency band;
A choke coil connected to the radiating element;
With
A loop of a magnetic field radiation type antenna is configured including the radiation element and the choke coil,
The antenna device, wherein the feeding coil is magnetically coupled or electromagnetically coupled to the choke coil in the second frequency band.
The radiating element generates a standing wave in the first frequency band,
The antenna device according to claim 1, wherein the loop resonates in the second frequency band.
The antenna device according to claim 1 or 2, wherein the feeding coil and the choke coil are separately provided.
The antenna device according to any one of claims 1 to 3, wherein the choke coil has a non-magnetic core or an air core.
The antenna device according to any one of claims 1 to 4, further comprising a ground conductor constituting a part of the loop.
The antenna device according to claim 5, wherein the choke coil is connected between the radiating element and the ground conductor.
Comprising at least two adjacent said radiating elements;
The antenna device according to claim 1, wherein the choke coil is connected between adjacent radiating elements.
An electronic device comprising an antenna device and a housing,
The antenna device is
A radiating element of a standing wave antenna having conductivity and connected to the first feeding circuit for the first frequency band;
A feeding coil connected to the second feeding circuit for the second frequency band;
A choke coil connected to the radiating element,
A loop of a magnetic field radiation type antenna is configured including the radiation element and the choke coil,
The electronic device, wherein the choke coil is magnetically or electromagnetically coupled to the feeding coil in the second frequency band.
The electronic device according to claim 8, wherein a part or all of the radiating element is a part or all of the casing.