JP6729148B2 - Antenna device, antenna module, and electronic device - Google Patents

Description

The present invention relates to an antenna device, and particularly to an antenna device including, for example, a plurality of coil antennas, an antenna module including the antenna device, and an electronic device.

Conventionally, an antenna device or an electronic device including an antenna coil for a near field communication (NFC: Near Field Communication) system and an antenna coil for a non-contact power transmission system is known (Patent Document 1).

International Publication No. 2014/167881

However, in the antenna device disclosed in Patent Document 1, since the coil antenna for NFC and the coil antenna for power transmission are unnecessarily coupled, both communication efficiency and power transmission efficiency are low. For example, the magnetic energy generated in the NFC coil antenna is absorbed in the power transmission coil antenna, which causes a problem that the communication efficiency is reduced. Note that such a problem occurs not only in an antenna device including a coil antenna for NFC and a coil antenna for power transmission, but also in a case where a plurality of coil antennas used in a plurality of systems are provided.

An object of the present invention is to provide an antenna device including a plurality of coil antennas used in a plurality of systems, in which unnecessary coupling between the coil antennas is suppressed and interaction (interference) between the plurality of coil antennas is suppressed. To provide. Another object of the present invention is to provide an antenna module and an electronic device including the antenna device.

(1) The antenna device of the present invention is
A first coil antenna having a first end and a second end;
A second coil antenna having a third end and a fourth end;
An inductor having a fifth end and a sixth end,
The second end of the first coil antenna, the fourth end of the second coil antenna, and the fifth end of the inductor are connected to each other,
The elements in the second row and second column of the impedance matrix of the two-terminal pair circuit formed by the terminal pair formed by the first end and the sixth end and the terminal pair formed by the third end and the sixth end are Z11, Z12, Z21, When represented by Z22 and the mutual inductor by the magnetic field coupling between the first coil antenna and the second coil antenna is represented by M12,
|Zii|>|Zij| (i,j)=(1,2), (2,1), or |Zij|<|M12| (i,j)=(1,2),(2,1) At least one of the above is established.

With this configuration, unnecessary coupling between the first coil antenna and the second coil antenna is suppressed. Therefore, in an antenna device including a first coil antenna and a second coil antenna used in two systems, respectively, an antenna device in which interaction (interference) between the first coil antenna and the second coil antenna is suppressed is realized. it can.

(2) In the above (1), the first coil antenna and the second coil antenna may be harmoniously connected.

(3) In the above (2), for example, the first coil antenna and the second coil antenna are wound around an axis, and the coil opening of the first coil antenna is viewed from the axial direction of the first coil antenna. At least partly overlaps the coil opening of the second coil antenna, and the winding direction from the first end to the second end of the first coil antenna, and from the fourth end of the second coil antenna. The winding direction up to the third end is the same.

(4) In the above (2), for example, the first coil antenna and the second coil antenna are wound around an axis, and the coil opening of the first coil antenna is viewed from the axial direction of the first coil antenna. And at least a part thereof does not overlap with the coil opening of the second coil antenna, the winding direction from the first end to the second end of the first coil antenna, and the fourth direction of the second coil antenna. The winding direction from the end to the third end is opposite.

(5) In any one of the above (1) to (4), it is preferable that the inductor and the first coil antenna are harmoniously connected. With this configuration, the first coil antenna and the inductor are coupled so as to reinforce each other, and the inductor also functions as an antenna, so that the antenna characteristics are improved.

(6) In any one of the above (1) to (5), it is preferable that the inductor and the second coil antenna are harmoniously connected. With this configuration, the second coil antenna and the inductor are coupled so as to reinforce each other, and the inductor also functions as an antenna, so that the antenna characteristics are improved.

(7) In any one of (1) to (4) above, the coupling coefficient between the inductor and the first coil antenna and the coupling coefficient between the inductor and the second coil antenna are the same as those of the first coil antenna. It is preferably smaller than the coupling coefficient with the second coil antenna. In this configuration, the inductor is not coupled to either the first coil antenna or the second coil antenna. Therefore, as compared with the case where the inductor and the coil antenna (first coil antenna, second coil antenna) are coupled, the circuit is not complicated and the circuit configuration is easy.

(8) In (7) above, it is preferable that the self-inductance of the inductor is equal to the mutual inductance M12. With this configuration, the influence of mutual inductance (unnecessary coupling) due to the magnetic field coupling between the first coil antenna and the second coil antenna is eliminated, and the interaction (interference) between the first coil antenna and the second coil antenna is eliminated. Therefore, it is possible to realize an antenna device in which the first coil antenna and the second coil antenna can be used completely independently.

(9) The antenna device of the present invention is
A first coil antenna having a first end and a second end;
A second coil antenna having a third end and a fourth end;
A third coil antenna having a seventh end and an eighth end;
A fourth coil antenna having a ninth end and a tenth end;
An inductor having a fifth end and a sixth end,
The second end of the first coil antenna, the fourth end of the second coil antenna, and the fifth end of the inductor are connected to each other,
The eighth end of the third coil antenna, the tenth end of the fourth coil antenna, and the sixth end of the inductor are connected to each other,
The elements in the second row and second column of the impedance matrix of the two-terminal pair circuit formed by the terminal pair formed by the first end and the seventh end and the terminal pair formed by the third end and the ninth end are Z11, Z12, Z21, Z22 represents a mutual inductor by magnetic field coupling between the first coil antenna and the second coil antenna by M12, and a mutual inductor by magnetic field coupling between the third coil antenna and the fourth coil antenna by M34.
|Zii|>|Zij| (i,j)=(1,2), (2,1), or |Zij|<|M12+M34| (i,j)=(1,2),(2,1) At least one of the above is established.

With this configuration, unnecessary coupling between the first coil antenna and the second coil antenna is suppressed, and unnecessary coupling between the third coil antenna and the fourth coil antenna is suppressed. Therefore, in the antenna device including the plurality of coil antennas used in each of the two systems, the interaction (interference) between the first coil antenna and the second coil antenna is suppressed, and the third coil antenna and the fourth coil antenna are It is possible to realize an antenna device in which the interaction (interference) is suppressed.

(10) In the above (9), the first coil antenna, the second coil antenna, the third coil antenna, and the fourth coil antenna may be harmoniously connected.

(11) In the above (10), for example, the first coil antenna, the second coil antenna, the third coil antenna, and the fourth coil antenna are wound around an axis, and the coil opening of the first coil antenna is provided. Is at least partially overlapped with the coil opening of the second coil antenna when viewed from the axial direction of the first coil antenna, and the coil opening of the third coil antenna is viewed from the axial direction of the third coil antenna. , At least part of which overlaps with the coil opening of the fourth coil antenna, the winding direction from the first end to the second end of the first coil antenna, and the fourth end of the second coil antenna. The winding direction up to the third end is the same, the winding direction from the seventh end to the eighth end of the third coil antenna, and the tenth end to the ninth end of the fourth coil antenna. The winding directions up to are the same.

(12) In the above (10), for example, the first coil antenna, the second coil antenna, the third coil antenna, and the fourth coil antenna are wound around an axis, and the coil opening of the first coil antenna is provided. When viewed from the axial direction of the first coil antenna, at least a part thereof does not overlap with the coil opening of the second coil antenna, and the coil opening of the third coil antenna is viewed from the axial direction of the third coil antenna. When viewed, at least a part thereof does not overlap the coil opening of the fourth coil antenna, the winding direction from the first end to the second end of the first coil antenna, and the second direction of the second coil antenna. The winding direction from the fourth end to the third end is opposite, and the winding direction from the seventh end to the eighth end of the third coil antenna and the tenth end of the fourth coil antenna The winding direction up to the ninth end is opposite.

(13) In any one of (9) to (12) above, it is preferable that the inductor, the first coil antenna, and the third coil antenna are harmoniously connected. With this configuration, the inductor, the first coil antenna, and the third coil antenna are coupled so as to reinforce each other, and the inductor also functions as an antenna, so that the antenna characteristics are improved.

(14) In any one of the above (9) to (13), it is preferable that the inductor, the second coil antenna, and the fourth coil antenna are harmoniously connected. With this configuration, the inductor, the second coil antenna, and the fourth coil antenna are coupled so as to strengthen each other's inductance, and the inductor also functions as an antenna, so that the antenna characteristics are improved.

(15) In any one of (9) to (12) above, a coupling coefficient between the inductor and the first coil antenna, a coupling coefficient between the inductor and the second coil antenna, the inductor and the third coil antenna. And a coupling coefficient between the inductor and the fourth coil antenna, a coupling coefficient between the first coil antenna and the second coil antenna, and a coupling coefficient between the third coil antenna and the fourth coil antenna. It is preferably smaller than the coupling coefficient. In this configuration, the inductor is not coupled to any of the first coil antenna, the second coil antenna, the third coil antenna and the fourth coil antenna. Therefore, as compared with the case where the inductor and the coil antenna (the first coil antenna, the second coil antenna, the third coil antenna, and the fourth coil antenna) are coupled, the circuit is not complicated and the circuit configuration is easy. Become.

(16) In the above (15), the self-inductance of the inductor is preferably equal to the sum of the mutual inductance M12 and the mutual inductance M34. With this configuration, the influence of mutual inductance (unnecessary coupling) due to the magnetic field coupling between the first coil antenna and the second coil antenna is eliminated, and the interaction (interference) between the first coil antenna and the second coil antenna is eliminated. At the same time, this configuration eliminates the influence of mutual inductance (unnecessary coupling) due to magnetic field coupling between the third coil antenna and the fourth coil antenna, and eliminates interaction (interference) between the third coil antenna and the fourth coil antenna. .. Therefore, it is possible to realize an antenna device in which the first system (first coil antenna and third coil antenna) and the second system (second coil antenna and fourth coil antenna) can be used completely independently.

(17) The antenna module of the present invention is
The antenna device according to any one of (1) to (8) above,
A first system circuit connected to the first end of the first coil antenna and the sixth end of the inductor;
A second system circuit connected to the third end of the second coil antenna and the sixth end of the inductor;
It is characterized by including.

With this configuration, it is possible to realize an antenna module including an antenna device in which the interaction (interference) between the first coil antenna and the second coil antenna is suppressed.

(18) The antenna module of the present invention is
The antenna device according to any one of (9) to (16) above,
A first system circuit connected to the first end of the first coil antenna and the seventh end of the third coil antenna;
A second system circuit connected to the third end of the second coil antenna and the ninth end of the fourth coil antenna;
It is characterized by including.

With this configuration, an antenna module including an antenna device in which the interaction (interference) between the first coil antenna and the second coil antenna is suppressed and the interaction (interference) between the third coil antenna and the fourth coil antenna is suppressed Can be realized.

(19) In the above (17) or (18), for example, the first system circuit is a circuit for non-contact power transmission.

(20) In any one of the above (17) to (19), for example, the second system circuit is a circuit for near field communication.

(21) In any one of (17) to (20) above, for example, the operating frequency band of the first system circuit is the HF band.

(22) In any one of (17) to (21) above, for example, the frequency band used by the second system circuit is the HF band.

(23) In any one of (17) to (22) above, for example, the center frequency of the used frequency band of the first system circuit is the same as the center frequency band of the used frequency band of the second system circuit. Different.

(24) The electronic device of the present invention is
A housing,
An antenna device housed in the housing;
A first system circuit and a second system circuit housed in the housing;
Equipped with
The antenna device is
A first coil antenna having a first end and a second end;
A second coil antenna having a third end and a fourth end;
An inductor having a fifth end and a sixth end,
The second end of the first coil antenna, the fourth end of the second coil antenna, and the fifth end of the inductor are connected to each other,
The elements in the second row and second column of the impedance matrix of the two-terminal pair circuit formed by the terminal pair formed by the first end and the sixth end and the terminal pair formed by the third end and the sixth end are Z11, Z12, Z21, When represented by Z22 and the mutual inductor by the magnetic field coupling between the first coil antenna and the second coil antenna is represented by M12,
|Zii|>|Zij| (i,j)=(1,2), (2,1), or |Zij|<|M12| (i,j)=(1,2),(2,1) At least one of
The first system circuit is connected to the first end of the first coil antenna and the sixth end of the inductor,
The second system circuit is connected to the third end of the second coil antenna and the sixth end of the inductor.

With this configuration, unnecessary coupling between the first coil antenna and the second coil antenna is suppressed. Therefore, in a configuration including a first coil antenna and a second coil antenna used in two systems respectively, an electronic device including an antenna device in which interaction (interference) between the first coil antenna and the second coil antenna is suppressed. A device can be realized.

(25) The electronic device of the present invention is
A housing,
An antenna device housed in the housing;
A first system circuit and a second system circuit housed in the housing;
Equipped with
The antenna device is
A first coil antenna having a first end and a second end;
A second coil antenna having a third end and a fourth end;
A third coil antenna having a seventh end and an eighth end;
A fourth coil antenna having a ninth end and a tenth end;
An inductor having a fifth end and a sixth end,
The second end of the first coil antenna, the fourth end of the second coil antenna, and the fifth end of the inductor are connected to each other,
The eighth end of the third coil antenna, the tenth end of the fourth coil antenna, and the sixth end of the inductor are connected to each other,
The elements in the second row and second column of the impedance matrix of the two-terminal pair circuit formed by the terminal pair formed by the first end and the seventh end and the terminal pair formed by the third end and the ninth end are Z11, Z12, Z21, Z22 represents a mutual inductor by magnetic field coupling between the first coil antenna and the second coil antenna by M12, and a mutual inductor by magnetic field coupling between the third coil antenna and the fourth coil antenna by M34.
|Zii|>|Zij| (i,j)=(1,2),(2,1), or |Zij|<M12+M34| (i,j)=(1,2),(2,1) The first system circuit, at least one of which is established, is connected to the first end of the first coil antenna and the seventh end of the third coil antenna,
The second system circuit is connected to the third end of the second coil antenna and the ninth end of the fourth coil antenna.

With this configuration, unnecessary coupling between the first coil antenna and the second coil antenna is suppressed, and unnecessary coupling between the third coil antenna and the fourth coil antenna is suppressed. Therefore, in a configuration including a plurality of coil antennas used respectively in two systems, the interaction (interference) between the first coil antenna and the second coil antenna and the interaction between the third coil antenna and the fourth coil antenna. An electronic device including an antenna device in which (interference) is suppressed can be realized.

According to the present invention, in an antenna device including a plurality of coil antennas used in a plurality of systems, unnecessary coupling between the coil antennas is suppressed, and interaction (interference) between the plurality of coil antennas is suppressed. Can be realized. Moreover, an antenna module and an electronic device including the antenna device can be obtained.

FIG. 1A is a plan view of an antenna unit 51 that is a part of the antenna device according to the first embodiment, and FIG. 1B is a first coil antenna 1 and a second coil antenna included in the antenna unit 51. It is a top view which shows 2. FIG. 2 is a plan view of the antenna module 201 according to the first embodiment. FIG. 3 is a circuit diagram of the antenna module 201 according to the first embodiment. FIG. 4A is a plan view of the antenna unit 52 that is a part of the antenna device according to the second embodiment, and FIG. 4B is the first coil antenna 1 and the second coil antenna included in the antenna unit 52. It is a top view which shows 2. FIG. 5 is a plan view of the antenna module 202 according to the second embodiment. FIG. 6A is a plan view of an antenna unit 53 which is a part of the antenna device according to the third embodiment, and FIG. 6B is a first coil antenna 1 and a second coil antenna included in the antenna unit 53. It is a top view which shows 2. FIG. 7 is a plan view of the antenna module 203 according to the third embodiment. FIG. 8 is a circuit diagram of the antenna module 203 according to the third embodiment. FIG. 9A is a plan view of the antenna unit 54 that is a part of the antenna device according to the fourth embodiment, and FIG. 9B is the first coil antenna 1 and the second coil antenna included in the antenna unit 54. It is a top view which shows 2 and the 5th coil antenna 5A. FIG. 10 is a plan view of the antenna module 204 according to the fourth embodiment. FIG. 11 is a circuit diagram of the antenna module 204 according to the fourth embodiment.

Hereinafter, some specific examples will be given with reference to the drawings to show a plurality of modes for carrying out the present invention. In each figure, the same parts are designated by the same reference numerals. Although the embodiments are shown separately for the sake of convenience in explaining the points or easiness of understanding, partial replacement or combination of the configurations shown in the different embodiments is possible. In the second and subsequent embodiments, description of matters common to the first embodiment will be omitted, and only different points will be described. In particular, similar effects obtained by the same configuration will not be sequentially described for each embodiment.

The “antenna device” in the present invention is an antenna device including a plurality of coil antennas used in a plurality of systems. The "antenna module" in the present invention is a module component including a plurality of power feeding circuits and the like. The "electronic device" in the present invention is a device in which the antenna device and a plurality of power supply circuits are housed in a housing, and is, for example, a mobile phone terminal, a so-called smartphone, a tablet terminal, a notebook PC or PDA, a wearable terminal (so-called smart Watches, smart glasses, etc.), cameras, game consoles, toys, etc.

<<First Embodiment>>
FIG. 1A is a plan view of an antenna unit 51 that is a part of the antenna device according to the first embodiment, and FIG. 1B is a first coil antenna 1 and a second coil antenna included in the antenna unit 51. It is a top view which shows 2. FIG. 2 is a plan view of the antenna module 201 according to the first embodiment. In FIG. 1(B) and FIG. 2, the first coil antenna 1 is shown by a broken line in order to make the structure of the first coil antenna 1 easy to understand.

The antenna module 201 includes an antenna device 101, a first system circuit 21, and a second system circuit 22. Further, the “electronic device” in the present invention includes a housing (not shown), the antenna device 101 housed in the housing, the first system circuit 21 housed in the housing, and the first electronic circuit housed in the housing. A circuit 22 for two systems is provided. This also applies to each of the following embodiments.

The first system circuit 21 is, for example, a power transmission circuit or a power reception circuit for a magnetic field-type non-contact power transmission system such as an electromagnetic induction power transmission system or a magnetic field resonance power transmission system. For example, the operating frequency band of the magnetic field resonance power transmission system is used in the HF band, particularly in the frequency band near the center frequency of 6.78 MHz. Further, the magnetic field-type non-contact power transmission system performs power transmission by magnetic field coupling with a power transmission partner. This power transmission system is used, for example, to charge an electronic device such as a smartphone. The magnetic field resonance power transmission system is an example of the "first system" in the present invention.

The second system circuit 22 is a power supply circuit for a communication system such as NFC, and is a balanced input/output type HF band IC or the like. The short-range wireless communication system is, for example, a system using NFC (Near field Communication). For example, the operating frequency band of the short-range wireless communication system is used in the HF band, particularly in the frequency band near the center frequency of 13.56 MHz. The short-range wireless communication system communicates with a communication partner by magnetic field coupling. The communication system using NFC is an example of the "second system" in the present invention.

The antenna device 101 includes a first coil antenna 1, a second coil antenna 2, and an inductor 5.

As shown in FIG. 1(A), the first coil antenna 1 is a conductor pattern in the shape of a rectangular spiral, which is formed on the surface of the base material 11 and is wound around the axis, about 2 turns. The first coil antenna 1 has a first end E1 and a second end E2. The first end E1 of the first coil antenna 1 is connected to the terminal electrode P1 via a conductor pattern or the like formed on the back surface of the base material 11. The second end E2 is connected to the terminal electrode P2 via a conductor pattern formed on the back surface of the base material 11. The first coil antenna 1 is, for example, a power receiving antenna or a power transmitting antenna used in a magnetic field type non-contact power transmission system. The base material 11 is a resin sheet such as polyimide (PI) or liquid crystal polymer (LCP).

As shown in FIG. 1(A), the second coil antenna 2 is a conductor pattern in the shape of a rectangle spiral, which is formed on the surface of the base material 11 and is wound around the axis. The second coil antenna 2 has a third end E3 and a fourth end E4. The third end E3 of the second coil antenna 2 is connected to the terminal electrode P3. The fourth end E4 of the second coil antenna 2 is connected to the second end E2 of the first coil antenna 1. Further, the fourth end E4 is connected to the terminal electrode P2 via a conductor pattern or the like formed on the back surface of the base material 11. The second coil antenna 2 is an antenna used in a communication system such as NFC.

In the present embodiment, the first coil antenna 1 and the second coil antenna 2 are harmoniously connected. Specifically, as shown in FIG. 1B, the coil opening of the first coil antenna 1 is the coil opening of the second coil antenna 2 when viewed from the axial direction (Z-axis direction) of the first coil antenna 1. Overlap with. In addition, the winding direction from the first end E1 to the second end E2 of the first coil antenna 1 (clockwise) and the winding direction from the fourth end E4 to the third end E3 of the second coil antenna 2 (right). Around) is the same.

The inductor 5 has a fifth end E5 and a sixth end E6. The fifth end E5 of the inductor 5 is connected to the terminal electrode P2. That is, the second end E2 of the first coil antenna 1, the fourth end E4 of the second coil antenna 2, and the fifth end E5 of the inductor 5 are connected to each other. The inductor 5 is, for example, a chip inductor.

The inductor 5 according to this embodiment is not coupled to either the first coil antenna 1 or the second coil antenna 2. For example, the coupling coefficient k51 between the inductor 5 and the first coil antenna 1 and the coupling coefficient k52 between the inductor 5 and the second coil antenna 2 are both the coupling coefficient k12 between the first coil antenna 1 and the second coil antenna 2. Smaller than (k51<k12) (k52<k12).

As shown in FIG. 2, the first system circuit 21 is connected to the first end E1 of the first coil antenna 1 and the sixth end E6 of the inductor 5. The second system circuit 22 is connected to the third end E3 of the second coil antenna 2 and the sixth end E6 of the inductor 5.

FIG. 3 is a circuit diagram of the antenna module 201 according to the first embodiment. In FIG. 3, the first coil antenna 1 is represented by the inductor L1, the second coil antenna 2 is represented by the inductor L2, the inductor 5 is represented by the inductor L5, and the first coil antenna 1 and the second coil antenna 2 are magnetically coupled. Mutual inductance is represented by M12. In FIG. 3, the power supply voltage of the first system circuit 21 is represented by V1, the current flowing through the inductor L1 is represented by I1, the power supply voltage for the second system is represented by V2, and the current flowing through the inductor L2 is represented by I2. It represents. This also applies to the circuit diagrams shown below.

At this time, the element in the second row and second column of the impedance matrix of the two-terminal pair circuit (antenna device 101) including the terminal pair including the first end E1 and the sixth end E6 and the terminal pair including the third end E3 and the sixth end E6. Is expressed by Z11, Z12, Z21, Z22, the circuit equation is as follows.

Further, if specific mathematical expressions are substituted for the elements Z11, Z12, Z21, Z22, the above circuit equation becomes as follows.

In the above circuit equation, the larger the values of the elements Z11 and Z22, the smaller the influence of the mutual inductance M12 (unnecessary coupling) due to the magnetic field coupling between the first coil antenna 1 and the second coil antenna 2. Specifically, it is preferable that |Z11|>|Z12| and |Z22|>|Z21| hold as shown in the following equation.

In the above circuit equation, the smaller the values of the elements Z12 and Z21, the smaller the influence of the mutual inductance M12 (unnecessary coupling) due to the magnetic field coupling between the first coil antenna 1 and the second coil antenna 2. Specifically, it is preferable that |Z12|<|M12| and |Z21|<|M12| hold as shown in the following equation.

In the present embodiment, the structure in which at least one of the above two formulas is satisfied suppresses unnecessary coupling between the first coil antenna 1 and the second coil antenna 2. Therefore, in the configuration including the first coil antenna 1 and the second coil antenna 2 used in the two systems respectively, the antenna in which the interaction (interference) between the first coil antenna 1 and the second coil antenna 2 is suppressed The device can be realized. Moreover, an antenna module and an electronic device including the antenna device can be obtained.

Further, the inductor L5 (self-inductance of the inductor 5) is preferably equal to the mutual inductance M12. That is, as shown in the following equation, it is preferable that |Z12|=0 and |Z21|=0 hold.

With this configuration, the influence of the mutual inductance M12 (unnecessary coupling) due to the magnetic field coupling between the first coil antenna 1 and the second coil antenna 2 is eliminated, and the interaction (interference) between the first coil antenna 1 and the second coil antenna 2 is eliminated. Disappears. Therefore, it is possible to realize an antenna device in which the first system (first coil antenna 1) and the second system (second coil antenna 2) can be used completely independently.

In addition, in the present embodiment, the inductor 5 is not coupled to either the first coil antenna 1 or the second coil antenna 2. Therefore, the circuit becomes complicated as compared with the case where the inductor and the coil antenna (the first coil antenna 1, the second coil antenna 2) are coupled (the antenna device 104 according to the fourth embodiment described in detail later). Therefore, the circuit configuration becomes easy.

Further, in the present embodiment, the coil opening of the first coil antenna 1 overlaps with the coil opening of the second coil antenna 2 when viewed from the Z-axis direction. Therefore, the area viewed from the axial direction of the first coil antenna can be reduced, and a small antenna device can be configured.

Further, in the present embodiment, an example in which the entire coil opening of the second coil antenna 2 overlaps the coil opening of the first coil antenna 1 when viewed from the Z-axis direction has been shown, but the present invention is not limited to this configuration. .. If the first coil antenna 1 and the second coil antenna are harmoniously connected, at least a part of the coil opening of the first coil antenna 1 when viewed from the Z-axis direction is the coil opening of the second coil antenna 2. The structure may be overlapped with.

<<Second Embodiment>>
The second embodiment shows an example in which the structures of the first coil antenna and the second coil antenna are different from those of the antenna device 101 according to the first embodiment.

FIG. 4A is a plan view of the antenna unit 52 that is a part of the antenna device according to the second embodiment, and FIG. 4B is the first coil antenna 1 and the second coil antenna included in the antenna unit 52. It is a top view which shows 2. FIG. 5 is a plan view of the antenna module 202 according to the second embodiment. In FIG. 4B and FIG. 5, the first coil antenna 1 is shown by a broken line in order to make the structure of the first coil antenna 1 easier to understand.

The antenna module 202 includes an antenna device 102, a first system circuit 21, and a second system circuit 22.

The antenna device 102 is different from the antenna device 101 according to the first embodiment in the structure of the first coil antenna 1 and the second coil antenna 2. Other configurations are substantially the same as the antenna device 101. Hereinafter, parts different from the antenna device 101 will be described.

In this embodiment, as shown in FIG. 4B, the coil opening of the first coil antenna 1 does not overlap with the coil opening of the second coil antenna 2 when viewed from the Z-axis direction. In addition, the winding direction from the first end E1 of the first coil antenna 1 to the second end E2 (clockwise) and the winding direction of the second coil antenna 2 from the fourth end E4 to the third end E3 (left). Around) is the opposite. Even with such a configuration, the first coil antenna 1 and the second coil antenna are harmoniously connected.

Even with such a configuration, the same operation and effect as the antenna device 101 can be obtained.

<<Third Embodiment>>
The third embodiment shows an antenna device including a first coil antenna, a second coil antenna, a third coil antenna and a fourth coil antenna.

FIG. 6A is a plan view of an antenna unit 53 which is a part of the antenna device according to the third embodiment, and FIG. 6B is a first coil antenna 1 and a second coil antenna included in the antenna unit 53. It is a top view which shows 2. FIG. 7 is a plan view of the antenna module 203 according to the third embodiment. In FIG. 6B and FIG. 7, the first coil antenna 1 and the fourth coil antenna 4 are shown by broken lines in order to make the structures of the first coil antenna 1 and the fourth coil antenna 4 easier to understand.

The antenna module 203 includes the antenna device 103, the first system circuit 21, and the second system circuit 22.

The antenna device 103 includes a first coil antenna 1, a second coil antenna 2, a third coil antenna 3, a fourth coil antenna 4, and an inductor 5. The first coil antenna 1 and the third coil antenna 3 are power reception antennas or power transmission antennas used in, for example, a magnetic field-type non-contact power transmission system. The second coil antenna 2 and the fourth coil antenna 4 are antennas used in a communication system such as NFC.

As shown in FIG. 6(A), the first coil antenna 1 is a conductor pattern in the form of a rectangular spiral with a little less than two turns formed on the surface of the base material 13 and wound around the axis. The first coil antenna 1 has a first end E1 and a second end E2. The first end E1 of the first coil antenna 1 is connected to the terminal electrode P1 via a conductor pattern or the like formed on the back surface of the base material 13. The second end E2 is connected to the terminal electrode P2 via a conductor pattern formed on the back surface of the base material 13.

As shown in FIG. 6(A), the second coil antenna 2 is a conductor pattern in the shape of a rectangular spiral with a little less than two turns formed on the surface of the base material 13 and wound around the axis. The second coil antenna 2 has a third end E3 and a fourth end E4. The third end E3 of the second coil antenna 2 is connected to the terminal electrode P3 via a conductor pattern or the like formed on the back surface of the base material 13. The fourth end E4 of the second coil antenna 2 is connected to the second end E2 of the first coil antenna 1. Further, the fourth end E4 is connected to the terminal electrode P2 via a conductor pattern or the like formed on the back surface of the base material 13.

As shown in FIG. 6A, the third coil antenna 3 is a conductor pattern in the shape of a rectangular spiral formed on the surface of the base material 13 and having about 2 turns wound around the axis. The third coil antenna 3 has a seventh end E7 and an eighth end E8. The seventh end E7 of the third coil antenna 3 is connected to the terminal electrode P4. The eighth end E8 is connected to the terminal electrode P5 via a conductor pattern or the like formed on the back surface of the base material 13.

As shown in FIG. 6A, the fourth coil antenna 4 is a rectangular spiral conductor pattern formed on the surface of the base material 13 and wound around the axis. The fourth coil antenna 4 has a ninth end E9 and a tenth end E10. The ninth end E9 of the fourth coil antenna 4 is connected to the terminal electrode P6 via a conductor pattern or the like formed on the back surface of the base material 13. The tenth end E10 of the fourth coil antenna 4 is connected to the eighth end E8 of the third coil antenna 3. The tenth end E10 is connected to the terminal electrode P5 via a conductor pattern formed on the back surface of the base material 13.

In the present embodiment, the first coil antenna 1 and the second coil antenna 2 are harmoniously connected, and the third coil antenna 3 and the fourth coil antenna 4 are harmoniously connected. Specifically, as shown in FIG. 6B, the coil opening of the first coil antenna 1 overlaps with the coil opening of the second coil antenna 2 when viewed from the Z-axis direction. The coil opening of the third coil antenna 3 overlaps with the coil opening of the fourth coil antenna 4 when viewed in the axial direction (Z-axis direction) of the third coil antenna. In addition, the winding direction from the first end E1 to the second end E2 of the first coil antenna 1 (clockwise) and the winding direction from the fourth end E4 to the third end E3 of the second coil antenna 2 (right). Around) is the same. Furthermore, the winding direction from the seventh end E7 to the eighth end E8 of the third coil antenna 3 (counterclockwise) and the winding direction from the tenth end E10 to the ninth end E9 of the fourth coil antenna 4 ( Counterclockwise) is the same.

The inductor 5 has a fifth end E5 and a sixth end E6. The fifth end E5 of the inductor 5 is connected to the terminal electrode P2, and the sixth end E6 of the inductor 5 is connected to the terminal electrode P5. That is, the second end E2 of the first coil antenna 1, the fourth end E4 of the second coil antenna 2, and the fifth end E5 of the inductor 5 are connected. The eighth end E8 of the third coil antenna 3, the tenth end E10 of the fourth coil antenna 4, and the sixth end E6 of the inductor 5 are connected.

The inductor 5 according to this embodiment is not coupled to any of the first coil antenna 1, the second coil antenna 2, the third coil antenna 3, and the fourth coil antenna 4. For example, the coupling coefficient k51 between the inductor 5 and the first coil antenna 1, the coupling coefficient k52 between the inductor 5 and the second coil antenna 2, the coupling coefficient k53 between the inductor 5 and the third coil antenna 3, and the inductor 5 and the The coupling coefficient k54 with the 4-coil antenna 4 is smaller than the coupling coefficient k12 between the first coil antenna 1 and the second coil antenna 2 (k51<k12) (k52<k12) (k53<k12) (k54< k12).

As shown in FIG. 7, the first system circuit 21 is connected to the first end E1 of the first coil antenna 1 and the seventh end E7 of the third coil antenna 3. The second system circuit 22 is connected to the third end E3 of the second coil antenna 2 and the ninth end E9 of the fourth coil antenna 4.

FIG. 8 is a circuit diagram of the antenna module 203 according to the third embodiment. In FIG. 8, the third coil antenna 3 is represented by an inductor L3, the fourth coil antenna 4 is represented by an inductor L4, and the mutual inductance due to magnetic field coupling between the third coil antenna 3 and the fourth coil antenna 4 is represented by M34. ..

At this time, the element in the second row and second column of the impedance matrix of the two-terminal pair circuit (antenna device 103) including the terminal pair including the first end E1 and the seventh end E7 and the terminal pair including the third end E3 and the ninth end E9. Is expressed by Z11, Z12, Z21, Z22, the circuit equation is as follows.

In the above circuit equation, the larger the value of the element Z11, the smaller the influence of the mutual inductance M12 due to the magnetic field coupling between the first coil antenna 1 and the second coil antenna 2. Further, in the above circuit equation, the larger the value of the element Z22, the smaller the influence of the mutual inductance M34 due to the magnetic field coupling between the third coil antenna 3 and the fourth coil antenna 4. Specifically, it is preferable that |Z11|>|Z12| and |Z22|>|Z21| hold as shown in the following equation.

In the above circuit equation, the smaller the value of the element Z12, the smaller the influence of the mutual inductance M12 due to the magnetic field coupling between the first coil antenna 1 and the second coil antenna 2. Further, in the above circuit equation, the smaller the value of the element Z21, the smaller the influence of the mutual inductance M34 due to the magnetic field coupling between the third coil antenna 3 and the fourth coil antenna 4. Specifically, it is preferable that |Z12|<|M12+M34| and |Z21|<|M12+M34| hold as shown in the following equation.

In the present embodiment, the structure in which at least one of the above two formulas is satisfied suppresses unnecessary coupling between the first coil antenna 1 and the second coil antenna 2 and unnecessary coupling between the third coil antenna 3 and the fourth coil antenna. To be done. Therefore, in a configuration including a plurality of coil antennas used in each of the two systems, the interaction (interference) between the first coil antenna 1 and the second coil antenna 2, and the third coil antenna 3 and the fourth coil antenna 4 An antenna device in which the interaction (interference) with is suppressed can be realized. Moreover, an antenna module and an electronic device including the antenna device can be obtained.

Further, the inductor L5 (self-inductance of the inductor 5) is preferably equal to the sum of the mutual inductance M12 and the mutual inductance M34. That is, as shown in the following equation, it is preferable that |Z12|=0 and |Z21|=0 hold.

With this configuration, the influence of the mutual inductance M12 (unnecessary coupling) due to the magnetic field coupling between the first coil antenna 1 and the second coil antenna 2 is eliminated, and the interaction (interference) between the first coil antenna 1 and the second coil antenna 2 is eliminated. Disappears. At the same time, with this configuration, the influence of the mutual inductance M34 (unnecessary coupling) due to the magnetic field coupling between the third coil antenna 3 and the fourth coil antenna 4 is eliminated, and the interaction between the third coil antenna 3 and the fourth coil antenna 4 is eliminated. (Interference) disappears. Therefore, it is possible to realize an antenna device in which the first system (first coil antenna 1 and third coil antenna 3) and the second system (second coil antenna 2 and fourth coil antenna 4) can be used completely independently. ..

In addition, in the present embodiment, the inductor 5 is not coupled to any of the first coil antenna 1, the second coil antenna 2, the third coil antenna 3, and the fourth coil antenna 4. Therefore, as compared with the case where the inductor and the coil antenna (the first coil antenna 1, the second coil antenna 2, the third coil antenna 3, and the fourth coil antenna 4) are coupled, the circuit is not complicated and the circuit Configuration becomes easy.

In the present embodiment, the coil opening of the first coil antenna 1 overlaps with the coil opening of the second coil antenna 2, and the coil opening of the third coil antenna 3 overlaps with the fourth coil opening as viewed from the Z-axis direction. Therefore, the area viewed from the axial direction of the first coil antenna can be reduced, and a small antenna device can be configured.

In the present embodiment, the coil opening of the first coil antenna 1, the coil opening of the second coil antenna 2, the coil opening of the third coil antenna 3, and the coil opening of the fourth coil antenna 4 are viewed from the Z-axis direction. Although the example in which they overlap each other has been shown, the present invention is not limited to this configuration. If the first coil antenna 1 and the second coil antenna 2 are harmoniously connected, at least a part of the coil opening of the first coil antenna 1 is the coil of the second coil antenna 2 when viewed from the Z-axis direction. It may be configured so as to overlap the opening. Moreover, if the third coil antenna 3 and the fourth coil antenna 4 are connected in a harmonious manner, at least a part of the coil opening of the third coil antenna 3 is viewed from the Z-axis direction. The coil opening may be overlapped.

Furthermore, if the first coil antenna 1 and the second coil antenna 2 are connected in a harmonious manner, the coil opening of the first coil antenna 1 is aligned with the coil opening of the second coil antenna 2 when viewed from the Z-axis direction. It does not have to overlap. In that case, the winding direction (clockwise) from the first end E1 to the second end E2 of the first coil antenna 1 and the winding direction from the fourth end E4 to the third end E3 of the second coil antenna 2. (Counterclockwise) is reversed. Similarly, if the third coil antenna 3 and the fourth coil antenna 4 are connected in a harmonious manner, the coil opening of the third coil antenna 3 is the coil opening of the fourth coil antenna 4 when viewed from the Z-axis direction. Does not have to overlap. In that case, a winding direction from the seventh end E7 to the eighth end E8 of the third coil antenna 3 (counterclockwise) and a winding direction from the tenth end E10 to the ninth end E9 of the fourth coil antenna 4. (Clockwise) is the opposite.

<<Fourth Embodiment>>
The fourth embodiment shows an antenna device in which the inductor is coupled to both the first coil antenna and the second coil antenna.

FIG. 9A is a plan view of the antenna unit 54 that is a part of the antenna device according to the fourth embodiment, and FIG. 9B is the first coil antenna 1 and the second coil antenna included in the antenna unit 54. It is a top view which shows 2 and the 5th coil antenna 5A. FIG. 10 is a plan view of the antenna module 204 according to the fourth embodiment. In FIG. 9(B) and FIG. 10, the fifth coil antenna 5A is shown by a broken line in order to facilitate understanding of the structure of the fifth coil antenna 5A.

The antenna module 204 includes the antenna device 104, the first system circuit 21, and the second system circuit 22.

The antenna device 104 differs from the antenna device 102 according to the second embodiment in that the antenna device 104 includes the fifth coil antenna 5A. Other configurations are substantially the same as the antenna device 102. Hereinafter, parts different from the antenna device 102 will be described.

As shown in FIG. 9A, the fifth coil antenna 5A is a rectangular spiral conductor pattern formed on the surface of the base material 14 and wound around the axis. The fifth coil antenna 5A has a fifth end E5 and a sixth end E6. The fifth end E5 of the fifth coil antenna 5A is connected to the second end E2 of the first coil antenna 1 and the fourth end E4 of the second coil antenna 2. The sixth end E6 of the fifth coil antenna 5A is connected to the terminal electrode P2.

In the present embodiment, the fifth coil antenna 5A corresponds to the "inductor" in the present invention.

The fifth coil antenna 5A is coupled to both the first coil antenna 1 and the second coil antenna 2. Specifically, as shown in FIG. 9B, the coil openings of the fifth coil antenna 5A are the same as the coil openings of the first coil antenna 1 and the second coil antenna 2 when viewed from the Z-axis direction. Both overlap. In addition, the winding direction (clockwise) from the first end E1 to the second end E2 of the first coil antenna 1 and the winding direction (right) from the fifth end E5 to the sixth end E6 of the fifth coil antenna 5A. Around) is the same. Thus, in the present embodiment, the first coil antenna 1 and the fifth coil antenna 5A are harmoniously connected. On the other hand, the winding direction from the fourth end E4 to the third end E3 of the second coil antenna 2 (counterclockwise) and the winding direction from the fifth end E5 to the sixth end E6 of the fifth coil antenna 5A (right). Around) is the opposite. Therefore, in the present embodiment, the second coil antenna 2 and the fifth coil antenna 5A are differentially connected.

Further, as shown in the second embodiment, the first coil antenna 1 and the second coil antenna 2 are harmoniously connected.

As shown in FIG. 10, the first system circuit 21 is connected to the first end E1 of the first coil antenna 1 and the sixth end E6 of the fifth coil antenna 5A (inductor). The second system circuit 22 is connected to the third end E3 of the second coil antenna 2 and the sixth end E6 of the fifth coil antenna 5A (inductor).

FIG. 11 is a circuit diagram of the antenna module 204 or the electronic device 304 according to the fourth embodiment. In FIG. 11, the fifth coil antenna 5A is represented by an inductor L5, the mutual inductance by magnetic field coupling between the first coil antenna 1 and the fifth coil antenna 5A is represented by M15, and the second coil antenna 2 and the fifth coil antenna 5A are represented. The mutual inductance due to the magnetic field coupling of is represented by M25.

At this time, the element in the second row and the second column of the impedance matrix of the two-terminal pair circuit (antenna device 104) including the terminal pair including the first end E1 and the sixth end E6 and the terminal pair including the third end E3 and the sixth end E6. Is expressed by Z11, Z12, Z21, Z22, the circuit equation is as follows.

In the above circuit equation, the larger the values of the elements Z11 and Z22, the smaller the influence of the mutual inductance M12 due to the magnetic field coupling between the first coil antenna 1 and the second coil antenna 2. Specifically, it is preferable that |Z11|>|Z12| and |Z22|>|Z21| hold as shown in the following equation.

In the above circuit equation, the smaller the values of the elements Z12 and M21, the smaller the influence of the mutual inductance M12 due to the magnetic field coupling between the first coil antenna 1 and the second coil antenna 2. Specifically, it is preferable that |Z12|<|M12| and |Z21|<|M12| hold as shown in the following equation.

In the present embodiment, the structure in which at least one of the above two formulas is satisfied suppresses unnecessary coupling between the first coil antenna 1 and the second coil antenna 2. Therefore, even in the configuration in which the fifth coil antenna 5A (“inductor” in the present invention) is coupled to the coil antennas (first coil antenna 1 and second coil antenna 2), the first coil antenna 1 and the second coil antenna 2 are An antenna device in which interaction (interference) is suppressed can be realized.

Further, the inductor L5 (self-inductance of the fifth coil antenna 5A) is preferably equal to a value obtained by subtracting the mutual inductance M12 from the sum of the mutual inductance M15 and the mutual inductance M25. That is, as shown in the following equation, it is preferable that |Z12|=0 and |Z21|=0 hold.

With this configuration, it is possible to realize an antenna device in which the first system (first coil antenna 1) and the second system (second coil antenna 2) can be used completely independently.

In the present embodiment, the first coil antenna 1 and the fifth coil antenna 5A (“inductor” in the present invention) are harmoniously connected. With this configuration, the first coil antenna 1 and the fifth coil antenna 5A are coupled so as to reinforce each other in inductance, and the fifth coil antenna 5A also functions as an antenna for the first system. Therefore, the antenna for the first system is used. The characteristics are improved. The second coil antenna 2 and the fifth coil antenna 5A may be harmoniously connected in order to improve the antenna characteristics for the second system.

Further, when the first coil antenna and the third coil antenna for the first system and the second coil antenna and the fourth coil antenna for the second system are provided as shown in the fourth embodiment, the fifth coil is used. It is preferable that the antenna 5A (the "inductor" in the present invention), the first coil antenna and the third coil antenna are harmoniously connected. With this configuration, the fifth coil antenna 5A, the first coil antenna, and the third coil antenna are coupled so as to reinforce each other, and the fifth coil antenna 5A also functions as an antenna for the first system. The antenna characteristics for the system are improved. Similarly, it is preferable that the fifth coil antenna 5A, the second coil antenna, and the fourth coil antenna are harmoniously connected. With this configuration, the antenna characteristics for the second system are improved.

If at least one of the above two equations |Zii|>|Zij| or |Zij|<|M12|(i,j)=(1,2)(2,1) holds, a plurality of coil antennas ( The method of coupling the first coil antenna 1, the second coil antenna 2, and the fifth coil antenna 5A) to each other can be arbitrarily changed. That is, as long as at least one of the above two equations is satisfied, any of the plurality of coil antennas may be connected in harmony or differentially, or one of the plurality of coil antennas may not be coupled. However, as described above, in order to improve the antenna characteristics, it is desirable that the fifth coil antenna 5A and the first coil antenna (or the second coil antenna) are harmoniously connected (mutual inductance M15>0, Or mutual inductance M25>0). When the mutual inductance M15>0 and the mutual inductance M25>0, the first coil antenna 1 and the second coil antenna 2 need to be harmoniously connected (mutual inductance M12>0).

<<Other Embodiments>>
In each of the embodiments described above, the plurality of coil antennas (the first coil antenna 1, the second coil antenna 2, the third coil antenna 3, the fourth coil antenna 4, and the fifth coil antenna 5A) are the surface of the base material. Although an example of a rectangular spiral conductor pattern of about 2 turns formed in the above is shown, the present invention is not limited to this configuration. The general shape of the plurality of coil antennas can be appropriately changed to a circular shape, an elliptical shape, a polygonal shape, or the like when viewed from the axial direction (Z axis direction). Further, the plurality of coil antennas may be a loop-shaped conductor, a helical conductor, or the like, or may be a helical laminated coil antenna in which base materials having loop-shaped or spiral-shaped conductors are laminated. Good. The configuration is not limited to the configuration in which all of the plurality of coil antennas are formed on the same plane. For example, when the plurality of coil antennas are provided in a base material (laminate) formed by laminating a plurality of insulating layers. The first coil antenna 1 and the second coil antenna 2 may be formed on different insulating layers. That is, the plurality of coil antennas may be formed on the front surface, the back surface, or the inside of the base material. Furthermore, the number of turns of the plurality of coil antennas can be changed as appropriate within the range in which the effects and advantages of the present invention are exhibited. The plurality of coil antennas may be winding coils. That is, the base material is not essential in the plurality of coil antennas.

In each of the above-described embodiments, the first system is a power transmission system such as an electromagnetic induction power transmission system or a magnetic field resonance power transmission system, and the second system is a communication system such as a short-range wireless communication system. However, the present invention is not limited to this. The first system and the second system may be different systems other than the communication system and the power transmission system.

Finally, the above description of the embodiments is illustrative in all respects and not restrictive. Those skilled in the art can appropriately make modifications and changes. The scope of the invention is indicated by the claims rather than by the embodiments described above. Further, the scope of the present invention includes modifications from the embodiments within the scope equivalent to the claims.

1... 1st coil antenna 2... 2nd coil antenna 3... 3rd coil antenna 4... 4th coil antenna 5... Inductor 5A... 5th coil antenna (inductor)
E1... 1st end of 1st coil antenna E2... 2nd end of 1st coil antenna E3... 3rd end of 2nd coil antenna E4... 4th end of 2nd coil antenna E5... 5th end of inductor E6... Inductor End E7 of the third coil antenna... Eighth end E8 of the third coil antenna... Eighth end E9 of the third coil antenna... Ninth end E10 of the fourth coil antenna... Tenth end k12, k51, k52 of the fourth coil antenna, k53, k54... Coupling coefficients L1, L2, L3, L4, L5... Inductors M12, M15, M25, M34... Mutual inductances P1, P2, P3, P4, P5, P6... Terminal electrodes 11, 12, 13, 14... Material 21... First system circuit 22... Second system circuit 51, 52, 53, 54... Antenna section 101, 102, 103, 104... Antenna device 201, 202, 203, 204... Antenna module

Claims (25)

A first coil antenna having a first end and a second end;
A second coil antenna having a third end and a fourth end;
An inductor having a fifth end and a sixth end,
The second end of the first coil antenna, the fourth end of the second coil antenna, and the fifth end of the inductor are connected to each other,
The elements in the second row and second column of the impedance matrix of the two-terminal pair circuit formed by the terminal pair formed by the first end and the sixth end and the terminal pair formed by the third end and the sixth end are Z11, Z12, Z21, When represented by Z22 and the mutual inductor by the magnetic field coupling between the first coil antenna and the second coil antenna is represented by M12,
|Zii|>|Zij| (i,j)=(1,2), (2,1), or |Zij|<|M12| (i,j)=(1,2),(2,1) An antenna device in which at least one of the above is established. The antenna device according to claim 1, wherein the first coil antenna and the second coil antenna are harmoniously connected. The first coil antenna and the second coil antenna are wound around an axis,
When viewed from the axial direction of the first coil antenna, at least a part of the coil opening of the first coil antenna overlaps the coil opening of the second coil antenna,
3. The winding direction from the first end to the second end of the first coil antenna and the winding direction from the fourth end to the third end of the second coil antenna are the same. The antenna device according to. The first coil antenna and the second coil antenna are wound around an axis,
At least a part of the coil opening of the first coil antenna does not overlap with the coil opening of the second coil antenna when viewed from the axial direction of the first coil antenna,
3. The winding direction from the first end to the second end of the first coil antenna is opposite to the winding direction from the fourth end to the third end of the second coil antenna. The antenna device according to. The antenna device according to claim 1, wherein the inductor and the first coil antenna are harmoniously connected. The antenna device according to claim 1, wherein the inductor and the second coil antenna are harmoniously connected. The coupling coefficient between the inductor and the first coil antenna and the coupling coefficient between the inductor and the second coil antenna are smaller than the coupling coefficient between the first coil antenna and the second coil antenna. 5. The antenna device according to any one of 4 to 4. The antenna device according to claim 7, wherein the self-inductance of the inductor is equal to the mutual inductance M12. A first coil antenna having a first end and a second end;
A second coil antenna having a third end and a fourth end;
A third coil antenna having a seventh end and an eighth end;
A fourth coil antenna having a ninth end and a tenth end;
An inductor having a fifth end and a sixth end,
The second end of the first coil antenna, the third end of the second coil antenna, and the fifth end of the inductor are connected to each other,
The eighth end of the third coil antenna, the tenth end of the fourth coil antenna, and the sixth end of the inductor are connected to each other,
The elements in the second row and second column of the impedance matrix of the two-terminal pair circuit formed by the terminal pair formed by the first end and the seventh end and the terminal pair formed by the third end and the ninth end are Z11, Z12, Z21, Z22 represents a mutual inductor by magnetic field coupling between the first coil antenna and the second coil antenna by M12, and a mutual inductor by magnetic field coupling between the third coil antenna and the fourth coil antenna by M34.
|Zii|>|Zij| (i,j)=(1,2), (2,1), or |Zij|<|M12+M34| (i,j)=(1,2),(2,1) An antenna device in which at least one of the above is established. The antenna device according to claim 9, wherein the first coil antenna, the second coil antenna, the third coil antenna, and the fourth coil antenna are harmoniously connected. The first coil antenna, the second coil antenna, the third coil antenna and the fourth coil antenna are wound around an axis,
When viewed from the axial direction of the first coil antenna, at least a part of the coil opening of the first coil antenna overlaps the coil opening of the second coil antenna,
When viewed from the axial direction of the third coil antenna, at least a part of the coil opening of the third coil antenna overlaps with the coil opening of the fourth coil antenna,
The winding direction from the first end to the second end of the first coil antenna and the winding direction from the fourth end to the third end of the second coil antenna are the same,
11. The winding direction from the seventh end to the eighth end of the third coil antenna and the winding direction from the tenth end to the ninth end of the fourth coil antenna are the same. The antenna device according to. The first coil antenna, the second coil antenna, the third coil antenna and the fourth coil antenna are wound around an axis,
At least a part of the coil opening of the first coil antenna does not overlap with the coil opening of the second coil antenna when viewed from the axial direction of the first coil antenna,
At least part of the coil opening of the third coil antenna does not overlap with the coil opening of the fourth coil antenna when viewed from the axial direction of the third coil antenna,
The winding direction from the first end to the second end of the first coil antenna is opposite to the winding direction from the fourth end to the third end of the second coil antenna,
11. The winding direction from the seventh end to the eighth end of the third coil antenna and the winding direction from the tenth end to the ninth end of the fourth coil antenna are opposite. The antenna device according to. The antenna device according to claim 9, wherein the inductor, the first coil antenna, and the third coil antenna are harmoniously connected. The antenna device according to claim 9, wherein the inductor, the second coil antenna, and the fourth coil antenna are harmoniously connected. A coupling coefficient between the inductor and the first coil antenna, a coupling coefficient between the inductor and the second coil antenna, a coupling coefficient between the inductor and the third coil antenna, and a coupling coefficient between the inductor and the fourth coil antenna. 13. The coupling coefficient according to claim 9, which is smaller than a coupling coefficient between the first coil antenna and the second coil antenna and a coupling coefficient between the third coil antenna and the fourth coil antenna. Antenna device. The antenna device according to claim 15, wherein the self-inductance of the inductor is equal to the sum of the mutual inductance M12 and the mutual inductance M34. An antenna device according to any one of claims 1 to 8,
A first system circuit connected to the first end of the first coil antenna and the sixth end of the inductor;
A second system circuit connected to the third end of the second coil antenna and the sixth end of the inductor;
An antenna module comprising. An antenna device according to any one of claims 9 to 16,
A first system circuit connected to the first end of the first coil antenna and the seventh end of the third coil antenna;
A second system circuit connected to the third end of the second coil antenna and the ninth end of the fourth coil antenna;
An antenna module comprising. The antenna module according to claim 17, wherein the first system circuit is a circuit for non-contact power transmission. The antenna module according to claim 17, wherein the second system circuit is a circuit for near field communication. The antenna module according to claim 17, wherein a frequency band used by the circuit for the first system is an HF band. 22. The antenna module according to claim 17, wherein a frequency band used by the circuit for the second system is an HF band. 23. The antenna module according to claim 17, wherein a center frequency of the use frequency band of the first system circuit is different from a center frequency band of the use frequency band of the second system circuit. A housing,
An antenna device housed in the housing;
A first system circuit and a second system circuit housed in the housing;
Equipped with
The antenna device is
A first coil antenna having a first end and a second end;
A second coil antenna having a third end and a fourth end;
An inductor having a fifth end and a sixth end,
The second end of the first coil antenna, the fourth end of the second coil antenna, and the fifth end of the inductor are connected to each other,
The elements in the second row and second column of the impedance matrix of the two-terminal pair circuit formed by the terminal pair formed by the first end and the sixth end and the terminal pair formed by the third end and the sixth end are Z11, Z12, Z21, When represented by Z22 and the mutual inductor by the magnetic field coupling between the first coil antenna and the second coil antenna is represented by M12,
|Zii|>|Zij| (i,j)=(1,2), (2,1), or |Zij|<|M12| (i,j)=(1,2),(2,1) At least one of
The first system circuit is connected to the first end of the first coil antenna and the sixth end of the inductor,
The second system circuit is an electronic device connected to the third end of the second coil antenna and the sixth end of the inductor. A housing,
An antenna device housed in the housing;
A first system circuit and a second system circuit housed in the housing;
Equipped with
The antenna device is
A first coil antenna having a first end and a second end;
A second coil antenna having a third end and a fourth end;
A third coil antenna having a seventh end and an eighth end;
A fourth coil antenna having a ninth end and a tenth end;
An inductor having a fifth end and a sixth end,
The second end of the first coil antenna, the fourth end of the second coil antenna, and the fifth end of the inductor are connected to each other,
The eighth end of the third coil antenna, the tenth end of the fourth coil antenna, and the sixth end of the inductor are connected to each other,
The elements in the second row and second column of the impedance matrix of the two-terminal pair circuit by the terminal pair formed by the first end and the seventh end and the terminal pair formed by the third end and the ninth end are Z11, Z12, Z21, Z22 represents a mutual inductor by magnetic field coupling between the first coil antenna and the second coil antenna by M12, and a mutual inductor by magnetic field coupling between the third coil antenna and the fourth coil antenna by M34.
|Zii|>|Zij| (i,j)=(1,2),(2,1), or |Zij|<M12+M34| (i,j)=(1,2),(2,1) At least one of the first system circuit is connected to the first end of the first coil antenna and the seventh end of the third coil antenna,
The second system circuit is an electronic device connected to the third end of the second coil antenna and the ninth end of the fourth coil antenna.

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