Antenna device and electronic equipment

Abstract

The invention provides an antenna device and an electronic apparatus which can increase the bandwidth of a usable frequency band. An antenna device (100) is provided with: a plate-shaped conductor (20) having an opening (25); an excitation electrode (51) and an excitation electrode (52) that are disposed at positions corresponding to the opening (25); a coil (L1), one end of which is electrically connected to the excitation electrode (51) and the other end of which is connected to a power supply circuit (30); and a coil (L2), one end of which is electrically connected to the excitation electrode (52). The coil (L1) and the coil (L2) are disposed at positions where magnetic field coupling is performed.

Description

Technical Field

[0001] The present disclosure relates to an antenna device and an electronic device. Background Art

[0002] In recent years, in electronic devices, from the viewpoint of design, a configuration has been adopted in which an antenna is not installed on the outside but is built in. In addition, by building in the antenna, breakage of the antenna due to dropping or the like can be prevented. A slot antenna is known as an antenna built in an electronic device (Patent Document 1: Japanese Patent Laid-Open No. 9-74312).

[0003] Prior art documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Laid-Open No. 9-74312 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] However, the resonance frequency of the slot antenna is determined by the length of the slot. Therefore, for an electronic device that requires operation in multiple frequency bands, the slot antenna is not suitable as a built-in antenna.

[0008] Therefore, an object of the present disclosure is to provide an antenna device and an electronic device that widen the usable frequency band.

[0009] Solutions to the Problems

[0010] An antenna device according to one aspect of the present disclosure includes: a plate-shaped conductor having an opening; a first excitation electrode and a second excitation electrode disposed at positions corresponding to the opening; a first coil having one end electrically connected to the first excitation electrode and the other end connected to a power supply circuit; and a second coil having one end electrically connected to the second excitation electrode. The first coil and the second coil are disposed at positions where magnetic field coupling occurs.

[0011] An electronic device according to one aspect of the present disclosure includes: the above-described antenna device; a power supply circuit that supplies power to the first excitation electrode; and a housing that houses the antenna device and the power supply circuit.

[0012] Effects of the Invention

[0013] According to one aspect of the present disclosure, by connecting the first excitation electrode and the second excitation electrode disposed at positions corresponding to the opening to the first coil and the second coil where magnetic field coupling occurs, respectively, resonance points can be added to widen the usable frequency band. Brief Description of the Drawings

[0014] Figure 1 It is a schematic diagram of an electronic device including the antenna device of Embodiment 1.

[0015] Figure 2 It is a diagram that magnifies a part of the antenna device of Embodiment 1.

[0016] Figure 3 It is a schematic cross-sectional view of the antenna device of Embodiment 1.

[0017] Figure 4 It is an equivalent circuit diagram of the antenna device of Embodiment 1.

[0018] Figure 5 It is a diagram showing the frequency characteristics of the reflection coefficient of the antenna device of Embodiment 1.

[0019] Figure 6 It is a diagram showing the Smith chart of the antenna device of Embodiment 1.

[0020] Figure 7 It is a schematic diagram of the antenna device of the comparison object.

[0021] Figure 8 It is a diagram showing the frequency characteristics of the reflection coefficient of the antenna device of the comparison object.

[0022] Figure 9 It is a diagram showing the Smith chart of the antenna device of the comparison object.

[0023] Figure 10 It is a perspective view of the antenna coupling element of Embodiment 1.

[0024] Figure 11 It is a top view of the antenna coupling element of Embodiment 1.

[0025] Figure 12 It is a first exploded top view showing the structure of the antenna coupling element of Embodiment 1.

[0026] Figure 13 It is a second exploded top view showing the structure of the antenna coupling element of Embodiment 1.

[0027] Figure 14 It is a schematic diagram of the antenna device of another comparison object.

[0028] Figure 15 It is a diagram showing the frequency characteristics of the reflection coefficient of the antenna device of another comparison object.

[0029] Figure 16 It is a diagram showing the Smith chart of the antenna device of another comparison object.

[0030] Figure 17 It is a schematic diagram of an antenna device of another comparison object.

[0031] Figure 18 It is a diagram showing the frequency characteristics of the reflection coefficient of an antenna device of another comparison object.

[0032] Figure 19 It is a diagram showing the Smith chart of an antenna device of another comparison object.

[0033] Figure 20 It is a diagram showing the frequency characteristics of the reflection coefficient of an antenna device in which the capacitance value of a capacitance element is changed.

[0034] Figure 21 It is a diagram showing the Smith chart of an antenna device in which the capacitance value of a capacitance element is changed.

[0035] Figure 22 It is a cross-sectional view of an antenna device of a modified example.

[0036] Figure 23 It is a schematic diagram of an electronic device including the antenna device of Embodiment 2.

[0037] Figure 24 It is a diagram showing the frequency characteristics of the reflection coefficient of the antenna device of Embodiment 2.

[0038] Figure 25 It is a diagram showing the antenna efficiency of the antenna device of Embodiment 2.

[0039] Figure 26 It is a schematic diagram of an electronic device including the antenna device of Modified Example 1 of Embodiment 2.

[0040] Figure 27 It is a schematic diagram of an electronic device including the antenna device of Modified Example 2 of Embodiment 2.

[0041] Figure 28 It is a schematic diagram of an electronic device including the antenna device of Modified Example 3 of Embodiment 2. Detailed Embodiments

[0042] Hereinafter, while referring to the drawings, the antenna device and the electronic device of the embodiment will be described in detail. In addition, the same or corresponding parts in the drawings are denoted by the same reference numerals and their description will not be repeated.

[0043] (Embodiment 1)

[0044] First, an electronic device including an antenna device will be described. Figure 1 It is a schematic diagram of an electronic device including the antenna device 100 of Embodiment 1. As Figure 1As shown, the electronic device includes: an antenna device 100; a power supply circuit 30 that supplies power to an excitation electrode 51 (first excitation electrode); and a housing 300 that houses the antenna device 100 and the power supply circuit 30. The electronic device is a notebook computer, mobile phone, smartphone, or tablet computer, etc. with an antenna device 100 built-in that can perform communication within frequency bands including, for example, the 2.4 GHz band and the 5 GHz - 7 GHz band.

[0045] [Structure of Antenna Device]

[0046] The antenna device 100 has an opening 25 (slot) that is longer in the X direction provided in a plate-shaped conductor 20, and excitation electrodes 51, 52 (excitation conductors, feed lines (Feed Line), or simply referred to as microstrip lines) are arranged at positions corresponding to the opening 25. Here, the excitation electrodes 51, 52 arranged at positions corresponding to the opening 25 mean a state where they at least partially overlap the opening 25 when viewed from above. That is, the antenna device 100 is a slot antenna in which the excitation electrodes 51, 52 act as capacitive power supply elements with respect to the opening 25. The length of the long side 25a (slot length) of the opening 25 of the antenna device 100 as a slot antenna becomes approximately half of the resonant wavelength (λ / 2). Therefore, when the antenna device 100 is used within the 2 - 3 GHz frequency band, the length of the long side 25a of the opening 25 becomes about 40 mm - 70 mm. On the other hand, the length of the short side 25b of the opening 25 (slot width) is about 1 - 5 mm shorter than the long side 25a. That is, the opening 25 has a rectangular shape in which the short side 25b (second side) is shorter than the long side 25a (first side). Here, the conductor 20 is, for example, a metal plate, such as a copper foil, copper plate, or aluminum plate.

[0047] The structure of the antenna device 100 will be described in further detail. Figure 2 This is a diagram enlarging a part of the antenna device 100 of Embodiment 1. Figure 3 This is a schematic cross-sectional view of the antenna device 100 of Embodiment 1. As Figure 1 shown, the excitation electrodes 51, 52 are arranged at positions overlapping the opening 25 when viewed from above. In addition, as Figure 3 shown, the excitation electrodes 51, 52 are formed on a substrate 40 arranged on the conductor 20, and thus are arranged at positions different from the opening 25 in the Z direction. Furthermore, the excitation electrodes 51, 52 only need to be arranged at positions corresponding to the opening 25, and can also be arranged at positions overlapping the opening 25 when viewed from above and overlapping the opening 25 in the Z direction. In addition, the excitation electrodes 51, 52 have a strip shape extending along the long side 25a of the opening 25.

[0048] Further, the excitation electrodes 51 and 52 are electrically connected to the antenna coupling element 10 mounted on the substrate 40. Here, the substrate 40 is, for example, a PWB (Printed Wired Board), and the antenna coupling element 10 is connected by solder or conductive paste. As Figure 1 shown, the excitation electrode 51 is connected to the power supply circuit 30 via the antenna coupling element 10, and power is supplied from the power supply circuit 30. On the other hand, the excitation electrode 52 (second excitation electrode) is connected to the substrate 40 via the antenna coupling element 10 and is connected to GND (grounded). That is, the slot antenna formed by the opening 25 and the excitation electrode 51 functions as a power supply antenna, and the slot antenna formed by the opening 25 and the excitation electrode 52 functions as a non-powered antenna.

[0049] The excitation electrode 51 extends from the antenna coupling element 10 in the left direction (first direction) in the figure, but the excitation electrode 52 extends from the antenna coupling element 10 in the right direction (second direction) in the figure. That is, the direction in which the excitation electrode 51 extends is opposite to the long side 25a of the opening 25 along the direction in which the excitation electrode 52 extends. In addition, the direction in which the excitation electrode 51 extends and the direction in which the excitation electrode 52 extends may also be the same direction.

[0050] The antenna coupling element 10 includes a coil L1 (first coil) and a coil L2 (second coil) as described later, and the coil L1 and the coil L2 are magnetically coupled. As Figure 2 shown, the excitation electrode 51 is electrically connected to the coil L1 by connecting to the first external electrode 11 of the antenna coupling element 10. The power supply circuit 30 is electrically connected to the coil L1 by connecting to the second external electrode 12 of the antenna coupling element 10 via the wiring 53. The excitation electrode 52 is electrically connected to the coil L2 by connecting to the third external electrode 13 of the antenna coupling element 10. However, the excitation electrode 52 is connected to the third external electrode 13 via a capacitor element 60 in order to adjust the impedance as described later. The fourth external electrode 14 of the antenna coupling element 10 is connected to the substrate 40 via the wiring 54, and the coil L2 is connected to GND.

[0051] The antenna device 100 has a structure in which resonance coupling performed by the two excitation electrodes 51 and 52 in the slot antenna is achieved using the antenna coupling element 10. Figure 4 is an equivalent circuit diagram of the antenna device 100 of Embodiment 1. The antenna device 100 uses the antenna coupling element 10 to couple the excitation electrode 51 of the slot antenna connected to the power supply circuit 30 and the excitation electrode 52 of the slot antenna not powered by the power supply circuit 30.

[0052] In Figure 4In the equivalent circuit diagram of the antenna device 100 shown, a slot antenna (first antenna) is formed by using the excitation electrode 51 and the opening 25. The excitation electrode 51 is electrically connected to the first external electrode 11 of the antenna coupling element 10, and the power supply circuit 30 is electrically connected to the second external electrode 12 of the antenna coupling element 10. That is, the coil L1 of the antenna coupling element 10 is connected in series with the excitation electrode 51 and the power supply circuit 30.

[0053] On the other hand, in the equivalent circuit diagram of the antenna device 100, a slot antenna (second antenna) is formed by using the excitation electrode 52 and the opening 25. The excitation electrode 52 is electrically connected to the third external electrode 13 of the antenna coupling element 10, and the fourth external electrode 14 of the antenna coupling element 10 is connected to GND (grounded). That is, the antenna coupling element 10 is connected in series with the excitation electrode 52 and GND. In addition, a capacitance element 60 is provided between the excitation electrode 52 and the third external electrode 13.

[0054] The coil L1 and the coil L2 are arranged at positions where magnetic field coupling occurs within the antenna coupling element 10, generating a mutual inductance M. In addition, the antenna coupling element 10 is a sheet-like coil element formed by laminating a plurality of ceramic green sheets. Of course, the antenna device 100 is not limited to the structure in which the excitation electrode 51 and the excitation electrode 52 are connected to the antenna coupling element 10 as a sheet-like coil element, and any structure may be used as long as the coil L1 and the coil L2 are arranged at positions where magnetic field coupling occurs.

[0055] Next, the characteristics of the antenna device 100 will be described. Figure 5 It is a diagram showing the frequency characteristics of the reflection coefficient of the antenna device 100 of Embodiment 1. In Figure 5 , the horizontal axis is the frequency and the vertical axis is the reflection coefficient (return loss). Here, the reflection coefficient A is the reflection coefficient of the antenna coupling element 10 side (that is, of the antenna device 100) as observed from the power supply circuit 30. In addition, the reflection coefficient A is the simulation result of the antenna device 100 when the coil L1 = 1.7 nH, the coil L2 = 1.1 nH, the coupling coefficient k = 0.33, and the capacitance element 60 = 0.3 pF. Figure 4 In the reflection coefficient A, resonance occurs at the resonance frequency of the fundamental wave of the antenna device 100 at the mark M1 (about 2.5 GHz). Moreover, in the reflection coefficient A, resonance occurs at the resonance frequencies of the higher harmonics of the antenna device 100 at the mark M2 (about 5.4 GHz) and the mark M3 (about 6.6 GHz). In the antenna device 100, by combining the slot antenna including the excitation electrode 52 with the slot antenna including the excitation electrode 51 by using the antenna coupling element 10, the number of resonance points can be increased and resonance can be generated in a relatively wide frequency band including about 5.0 GHz to about 7.0 GHz.

[0056] In the reflection coefficient A, resonance occurs at the resonance frequency of the fundamental wave of the antenna device 100 at the mark M1 (about 2.5 GHz). Moreover, in the reflection coefficient A, resonance occurs at the resonance frequencies of the higher harmonics of the antenna device 100 at the mark M2 (about 5.4 GHz) and the mark M3 (about 6.6 GHz). In the antenna device 100, by combining the slot antenna including the excitation electrode 52 with the slot antenna including the excitation electrode 51 by using the antenna coupling element 10, the number of resonance points can be increased and resonance can be generated in a relatively wide frequency band including about 5.0 GHz to about 7.0 GHz.

[0057] Moreover, Figure 6 is a Smith chart showing the antenna device 100 of Embodiment 1. In Figure 6 the shown Smith chart, it is shown that a capacitance element 60 is provided between the coil L2 and the excitation electrode 52 of the antenna device 100 shown in Figure 4 to adjust the impedance of the antenna device 100. In addition, as Figure 1 shown, the antenna device 100 also adjusts the impedance by making the length of the excitation electrode 52 in the X direction shorter than the length of the excitation electrode 51 in the X direction.

[0058] In Figure 6 the shown Smith chart, the lines of the target frequencies from 2 GHz to 8 GHz draw the circle relatively large near the respective marks M1 (about 2.5 GHz), M2 (about 5.4 GHz), and M3 (about 6.6 GHz). Therefore, from Figure 6 the shown Smith chart, it is also judged that: in addition to the fundamental resonance frequency (about 2.5 GHz), the antenna device 100 also increases the resonance points to generate resonance in a relatively wide frequency band including from about 5.0 GHz to about 7.0 GHz.

[0059] Here, the characteristics of the antenna device of the comparison target will be described. Figure 7 is a schematic diagram of the antenna device 200 of the comparison target. The antenna device 200 has a structure in which a slot antenna including the excitation electrode 51 is not combined with a slot antenna including the excitation electrode 52 by using the antenna combining element 10 as in the antenna device 100, but only includes a slot antenna including the excitation electrode 51. In addition, in the antenna device 200, the same reference numerals are given to the constituent elements that are the same as those of the antenna device 100 shown in Figure 1 and detailed description will not be repeated.

[0060] The antenna device 200 is provided with the excitation electrode 51 at a position corresponding to the opening 25. The excitation electrode 51 is connected to a power supply circuit 30 (not shown) by wiring on the substrate 40, and power is supplied from the power supply circuit 30. The slot antenna composed of the opening 25 and the excitation electrode 51 functions as a power supply antenna.

[0061] Next, the characteristics of the antenna device 200 will be described. Figure 8 is a diagram showing the frequency characteristics of the reflection coefficient of the antenna device 200 of the comparison target. In Figure 8 , the horizontal axis is the frequency and the vertical axis is the reflection coefficient (return loss). Here, the reflection coefficient B is the reflection coefficient of the antenna device 200.

[0062] In the reflection coefficient B, resonance occurs at the resonance frequency of the fundamental wave of the antenna device 200 at the mark M4 (about 2.5 GHz). Also, in the reflection coefficient B, resonance occurs at the resonance frequency of the harmonic wave of the antenna device 200 at the mark M5 (about 5.5 GHz). In the antenna device 200, just by causing resonance to occur near about 5.5 GHz, resonance cannot be caused to occur in a relatively wide frequency band including about 5.0 GHz to about 7.0 GHz as in the antenna device 100.

[0063] Also, Figure 9 is a Smith chart showing the antenna device 200 that is an object of comparison. In Figure 9 the shown Smith chart, the lines of the target frequencies from 2 GHz to 8 GHz draw a relatively large circle near each of the mark M4 (about 2.5 GHz) and the mark M5 (about 5.5 GHz). Therefore, it is also determined from Figure 9 the shown Smith chart that: the antenna device 200 causes resonance to occur not only at the resonance frequency of the fundamental wave (about 2.5 GHz), but also at about 5.5 GHz.

[0064] [Structure of Antenna Combining Element]

[0065] Next, the structure of the antenna combining element 10 that combines the slot antenna including the excitation electrode 52 and the slot antenna including the excitation electrode 51 will be described. Figure 10 is a perspective view of the antenna combining element 10 of Embodiment 1. Figure 11 is a top view of the antenna combining element 10 of Embodiment 1. Here, in Figures 10 to 11 the short side direction of the antenna combining element 10 is set as the X direction, the long side direction is set as the Y direction, and the height direction is set as the Z direction. In addition, the stacking direction of the substrate is the Z direction, and the direction of the arrow indicates the upper layer direction.

[0066] The antenna combining element 10 is an antenna combining element that magnetically couples the resonances respectively performed by the two excitation electrodes 51 and 52 in the slot antenna, and is a rectangular parallelepiped-shaped sheet-like component. On the outer surface of the antenna combining element 10, as Figure 1 shown, the first external electrode 11, the second external electrode 12, the third external electrode 13, and the fourth external electrode 14 are formed. In addition, the antenna combining element 10 has a pair of main surfaces facing each other, Figure 1 and the lower main surface of

[0067] is the mounting surface, and this surface faces the circuit board. The antenna combining element 10 internally incorporates two coils L1 and L2 in order to magnetically couple the resonances respectively performed by the two excitation electrodes 51 and 52 in the slot antenna, and constitutes a transformer in which the coil L1 and the coil L2 perform magnetic coupling.

[0068] The specific structure of the antenna coupling element 10 will be described. The antenna coupling element 10 is composed of an insulator 1 (ceramic body) of a ceramic layer formed by laminating a plurality of Figures 10 to 11 substrates (green ceramic sheets) with wiring formed with coils as shown. The insulator 1 has a pair of main surfaces facing each other and side surfaces connecting between the main surfaces. A plurality of first conductor patterns 21, second conductor patterns 22, a plurality of third conductor patterns 23, and a fourth conductor pattern 24 are stacked in parallel with respect to the main surface of the insulator 1 to constitute the antenna coupling element 10 in which a coil L1 and a coil L2 are incorporated.

[0069] The coil L1 stacks two layers of the first conductor patterns 21a, 21b and one layer of the second conductor pattern 22 and electrically connects the respective conductor patterns by via conductors 31. Specifically, the coil L1 uses the via conductor 31 to connect the two layers of the first conductor patterns 21, i.e., the first conductor pattern 21a and the first conductor pattern 21b, in parallel, and uses the via conductor 31 to connect the second conductor pattern 22 in series with the two layers of the first conductor patterns 21. Therefore, the coil L1 can reduce the inductance component compared with the case where the first conductor pattern 21a and the second conductor pattern 22 are connected in series. In addition, the first conductor pattern 21 may be two or more layers of conductor patterns.

[0070] The coil L2 stacks two layers of the third conductor patterns 23a, 23b and one layer of the fourth conductor pattern 24 and electrically connects the respective conductor patterns by via conductors 32. Specifically, the coil L2 uses the via conductor 32 to connect the two layers of the third conductor patterns 23, i.e., the third conductor pattern 23a and the third conductor pattern 23a, in parallel, and uses the via conductor 32 to connect the fourth conductor pattern 24 in series with the two layers of the third conductor patterns 23. Therefore, the coil L2 can reduce the inductance component compared with the case where the third conductor pattern 23a and the fourth conductor pattern 24 are connected in series. In addition, the third conductor pattern 23 may be two or more layers of conductor patterns.

[0071] The coil L1 and the coil L2 are arranged in the insulator 1 such that the opening of the coil L1 and the opening of the coil L2 at least partially overlap when viewed from the lamination direction of the insulator 1. In addition, when the coil L1 and the coil L2 are viewed from the lamination direction of the insulator 1, as Figure 11 shown, the openings of the coil L1 and the coil L2 are arranged so as to deviate in the long side direction with respect to the center of the antenna coupling element 10, and are arranged in the direction closer to the second external electrode 12 provided on the short side of the antenna coupling element 10. However, Figure 11The configuration of the coils L1 and L2 shown is an example, and other configurations are also possible. Specifically, the coils L1 and L2 are arranged in the insulator 1 such that the second conductor pattern 22 and the fourth conductor pattern 24 face each other. The coils L1 and L2 form a structure in which the single-layer second conductor pattern 22 and the single-layer fourth conductor pattern 24 face each other with an insulating layer therebetween. Therefore, compared with a structure in which three-layer conductor patterns face each other with an insulating layer therebetween, the capacitance component is reduced.

[0072] In addition, when the coils L1 and L2 are arranged such that the second conductor pattern 22 and the fourth conductor pattern 24 face each other, the coupling coefficient between the coils L1 and L2 can be maintained at a relatively high level compared with the case where the coils L1 and L2 are arranged such that the two-layer first conductor pattern 21 and the two-layer third conductor pattern 23 face each other. Therefore, in the antenna coupling element 10, since the coils L1 and L2 are arranged such that the second conductor pattern 22 and the fourth conductor pattern 24 face each other, the mutual inductance M between the coils L1 and L2 is not reduced.

[0073] As Figure 10 shown, on the side surface of the insulator 1, a first external electrode 11 is provided on one side of the short side, a second external electrode 12 is provided on the other side of the short side, a third external electrode 13 is provided on one side of the long side, and a fourth external electrode 14 is provided on the other side of the long side.

[0074] The plurality of first conductor patterns 21 are each electrically connected to the first external electrode 11. Alternatively, only the lower first conductor pattern 21b among the plurality of first conductor patterns 21 may be electrically connected to the first external electrode 11, and the upper first conductor pattern 21a may be electrically connected to the first conductor pattern 21b via a via conductor. The second conductor pattern 22 is electrically connected to the second external electrode 12.

[0075] The plurality of third conductor patterns 23 are each electrically connected to the third external electrode 13. Alternatively, only the lower third conductor pattern 23b among the plurality of third conductor patterns 23 may be electrically connected to the third external electrode 13, and the upper third conductor pattern 23a may be electrically connected to the third conductor pattern 23b via a via conductor. The fourth conductor pattern 24 is electrically connected to the fourth external electrode 14.

[0076] [Exploded top view of the antenna coupling element]

[0077] Next, the structure of each layer will be described using the exploded top view. Figure 12 is the first exploded top view showing the structure of the antenna coupling element 10 according to the first embodiment. Figure 13 is the second exploded top view showing the structure of the antenna coupling element 10 according to the first embodiment. First, as Figures 12 to 13As shown, for each of the first conductor patterns 21 to 24, a conductive paste (Ni paste) is printed onto the green ceramic wafers 1a to 1o serving as substrates by screen printing to form the conductor patterns.

[0078] On the green ceramic wafer 1a, conductor patterns 11a to 14a are formed at positions corresponding to the first to fourth external electrodes 11 to 14 as shown in (a) of Figure 12 . In addition, a direction identification mark DDM indicating the direction of the top surface, which is the side opposite to the mounting surface, is given to the green ceramic wafer 1a. For example, this direction identification mark DDM is used to detect the direction of a chip component such as the antenna bonding element 10 when mounting the chip component onto the circuit board using a mounter. On the green ceramic wafers 1b to 1e, no conductor patterns are formed as shown in (b) to Figure 12 (e) of Figure 12 .

[0079] As shown in (f) of Figure 12 , a third conductor pattern 23a is formed on the green ceramic wafer 1f. The third conductor pattern 23a is formed in such a manner that it rotates approximately 1 / 2 to 3 / 4 of a turn to the right from the center of the upper long side of the green ceramic wafer 1f in the figure. In addition, the starting end of the third conductor pattern 23a forms the conductor pattern to the outer peripheral portion of the green ceramic wafer 1f in such a manner that it can be electrically connected to the third external electrode 13. On the other hand, a connection portion 32a for connecting to the via hole conductor 32 is provided at the terminal of the third conductor pattern 23a.

[0080] As shown in (g) of Figure 12 , a third conductor pattern 23b is formed on the green ceramic wafer 1g. The third conductor pattern 23b is formed in such a manner that it rotates approximately 1 / 2 to 3 / 4 of a turn to the right from the center of the upper long side of the green ceramic wafer 1g in the figure. In addition, the starting end of the third conductor pattern 23b forms the conductor pattern to the outer peripheral portion of the green ceramic wafer 1g in such a manner that it can be electrically connected to the third external electrode 13. On the other hand, a connection portion 32b for connecting to the via hole conductor 32 is provided at the terminal of the third conductor pattern 23b.

[0081] As shown in (h) of Figure 12 , a fourth conductor pattern 24 is formed on the green ceramic wafer 1h. The fourth conductor pattern 24 is formed in such a manner that it rotates approximately 1 / 2 to 3 / 4 of a turn to the left from the center of the lower long side of the green ceramic wafer 1h in the figure. In addition, the starting end of the fourth conductor pattern 24 forms the conductor pattern to the outer peripheral portion of the green ceramic wafer 1h in such a manner that it can be electrically connected to the fourth external electrode 14. On the other hand, a connection portion 32c for connecting to the via hole conductor 32 is provided at the terminal of the fourth conductor pattern 24.

[0082] As shown in Figure 13As shown in (i), no conductor pattern is formed on the green ceramic sheet 1i. That is to say, the interlayer distance between the fourth conductor pattern 24 and the second conductor pattern 22 of the antenna coupling element 10 is longer than the interlayer distance between the third conductor pattern 23a and the third conductor pattern 23b, or the interlayer distance between the third conductor pattern 23b and the fourth conductor pattern 24. In this way, the antenna coupling element 10 can adjust the coupling degree between the coil L1 and the coil L2 by adjusting the interlayer distance between the fourth conductor pattern 24 and the second conductor pattern 22.

[0083] As Figure 13 As shown in (j), the second conductor pattern 22 is formed on the green ceramic sheet 1j. The second conductor pattern 22 is formed in a manner of rotating approximately half a turn to the left from the center of the short side on the left side in the figure of the green ceramic sheet 1j. In addition, the starting end of the second conductor pattern 22 forms a conductor pattern to the outer peripheral portion of the green ceramic sheet 1j in a manner capable of being electrically connected to the second external electrode 12. On the other hand, a connection portion 31a connected to the via conductor 31 is provided at the terminal end of the second conductor pattern 22.

[0084] As Figure 13 As shown in (k), the first conductor pattern 21a is formed on the green ceramic sheet 1k. The first conductor pattern 21a is formed in a manner of rotating approximately 3 / 4 to 1 turn to the right from the center of the short side on the right side in the figure of the green ceramic sheet 1k. In addition, the starting end of the first conductor pattern 21a forms a conductor pattern to the outer peripheral portion of the green ceramic sheet 1k in a manner capable of being electrically connected to the first external electrode 11. On the other hand, a connection portion 31b connected to the via conductor 31 is provided at the terminal end of the first conductor pattern 21a.

[0085] As Figure 13 As shown in (l), only the connection portion 31c connected to the via conductor 31 is provided on the green ceramic sheet 1l, and no conductor pattern is formed. That is to say, the interlayer distance between the first conductor pattern 21a and the first conductor pattern 21b of the antenna coupling element 10 is longer than the interlayer distance between the third conductor pattern 23a and the third conductor pattern 23b, or the interlayer distance between the first conductor pattern 21b and the second conductor pattern 22. In addition, the first conductor pattern 21b is the first conductor pattern among the plurality of first conductor patterns 21 that faces the second conductor pattern 22. In this way, the antenna coupling element 10 can adjust the inductance component of the coil L1 by adjusting the interlayer distance between the first conductor pattern 21a and the first conductor pattern 21b.

[0086] As Figure 13As shown in (m), a first conductor pattern 21b is formed on the green ceramic sheet 1m. The first conductor pattern 21b is formed in such a manner that it rotates approximately 3 / 4 to one full turn to the right from the center of the short side on the right side of the green ceramic sheet 1m in the figure. In addition, the starting end of the first conductor pattern 21b forms a conductor pattern on the outer peripheral portion of the green ceramic sheet 1m in a manner that can be electrically connected to the first external electrode 11. On the other hand, a connection portion 31d connected to the via hole conductor 31 is provided at the terminal of the first conductor pattern 21b.

[0087] As Figure 13 shown in (n), no conductor pattern is formed on the green ceramic sheet 1n. Moreover, as shown in (o) of Figure 13 the green ceramic sheet 1o, conductor patterns 11b to 14b are formed at positions corresponding to the first external electrode 11 to the fourth external electrode 14.

[0088] In addition, it is described that the substrate constituting the insulator 1 is a green ceramic sheet, but it can also be a non-magnetic ceramic insulator made of LTCC (Low Temperature Co-fired Ceramics) or the like, or a resin insulator made of resin materials such as polyimide and liquid crystal polymer. Thus, the antenna coupling element 10 functions as an antenna coupling element even in a high-frequency band exceeding several hundred MHz by using a non-magnetic material for the substrate constituting the insulator 1 (since it is not a ferromagnetic ferrite).

[0089] In addition, each conductor pattern and the via hole conductor are formed of a conductor material with a relatively low resistivity mainly composed of Ag and Cu. If the substrate constituting the insulator 1 is a ceramic, for example, it is formed by screen printing and firing a conductive paste mainly composed of Ag and Cu. In addition, if the substrate constituting the insulator 1 is a resin, for example, it is formed by patterning a metal foil such as Al foil or Cu foil by using etching or the like. Figures 10 to 13 The shown antenna coupling element 10 is an example. The antenna coupling element 10 is not limited to this structure if it incorporates at least two coils L1 and L2 and constitutes a transformer in which the coils L1 and L2 are magnetically coupled. For example, the antenna coupling element 10 may also include a conductor pattern among the multiple conductor patterns constituting the coil L1 that is not electrically connected to the first external electrode 11 or the second external electrode 12, or may also include a conductor pattern among the multiple conductor patterns constituting the coil L2 that is not electrically connected to the third external electrode 13 or the fourth external electrode 14.

[0090] [Coupling of Two Antennas by Antenna Coupling Element]

[0091] In the antenna device 100, the slot antenna including the excitation electrode 52 is combined with the slot antenna including the excitation electrode 51 by the antenna combining element 10. That is, in the antenna device 100, the resonance performed by the two excitation electrodes 51 and 52 respectively in the slot antenna is magnetically coupled by the coils L1 and L2 constituting the transformer. Specifically, the power supply circuit 30 is connected to the second external electrode 12 of the antenna combining element 10, and the excitation electrode 51 is connected to the first external electrode 11. Therefore, when power is supplied from the power supply circuit 30 to the excitation electrode 51, the current I1 flows in the first conductor patterns 21a and 21b and the second conductor pattern 22. The current I1 flows in the second conductor pattern 22 in the direction toward the connection portion 31a as shown by the arrow in (j) of Figure 13 and flows in the first conductor patterns 21a and 21b in the directions away from the connection portions 31b and 31d as shown by the arrows in (k) and (m) of Figure 13 . The coil L2 constituting the transformer causes the current I2 generated by the reverse magnetic field to flow into the coil L2 in such a way as to cancel the magnetic field generated in the coil L1 due to the current I1. That is, the current I2 flows in the third conductor patterns 23a and 23b in the directions toward the connection portions 32a and 32b as shown by the arrows in (f) and (g) of Figure 12 and flows in the fourth conductor pattern 24 in the direction away from the connection portion 32c as shown by the arrow in (h) of Figure 12 .

[0092] Thus, the combination of the slot antenna including the excitation electrode 52 and the slot antenna including the excitation electrode 51 by the antenna combining element 10 has the effect of increasing the resonance points in the antenna device 100 and generating resonance in a wide frequency band, and will be described by comparison with other antenna devices as comparison objects. Figure 14 is a schematic diagram of another antenna device 201 as a comparison object. The antenna device 201 has a structure in which the excitation electrode 51 and the excitation electrode 52 are not connected to the antenna combining element 10 as in the antenna device 100, but are connected in parallel to the substrate 40. In addition, in the antenna device 201, the same reference numerals are assigned to the constituent elements identical to those of the antenna device 100 shown in Figure 1 , and detailed description thereof will not be repeated.

[0093] The antenna device 201 is provided with excitation electrodes 51 and 52 at positions corresponding to the opening 25. The excitation electrode 51 is not connected to the antenna coupling element 10, but is connected to a power supply circuit 30 (not shown) via the wiring of the substrate 40, and power is supplied from the power supply circuit 30. On the other hand, the excitation electrode 52 is not connected to the antenna coupling element 10, but is connected to the substrate 40 and connected to GND (grounded). That is, in the antenna device 201, the slot antenna formed by the opening 25 and the excitation electrode 51 functions as a power supply antenna, and the slot antenna formed by the opening 25 and the excitation electrode 52 functions as a non-powered antenna. However, only electric field coupling occurs between the excitation electrode 51 and the excitation electrode 52, and no magnetic field coupling occurs.

[0094] Next, the characteristics of the antenna device 201 will be described. Figure 15 It is a diagram showing the frequency characteristics of the reflection coefficient of the antenna device 201 of another comparison object. In Figure 15 , the horizontal axis is the frequency, and the vertical axis is the reflection coefficient (return loss). Here, the reflection coefficient C is the reflection coefficient of the antenna device 201.

[0095] In the reflection coefficient C, resonance occurs at the resonance frequency of the fundamental wave of the antenna device 201 at the mark M6 (about 2.6 GHz). Moreover, in the reflection coefficient C, resonance occurs at the resonance frequency of the higher harmonic of the antenna device 201 at the mark M7 (about 5.6 GHz). In the antenna device 201, only by generating resonance near about 5.6 GHz, resonance points are not added like the antenna device 100, and resonance cannot be generated in a relatively wide frequency band including about 5.0 GHz to about 7.0 GHz.

[0096] Moreover, Figure 16 It is a diagram showing the Smith chart of the antenna device 201 of another comparison object. In the Smith chart shown in Figure 16 , the lines of the target frequencies from 2 GHz to 8 GHz draw a relatively large circle near each of the mark M6 (about 2.6 GHz) and the mark M7 (about 5.6 GHz). Therefore, it can also be judged from the Smith chart shown in Figure 16 that the antenna device 201 generates resonance only at about 5.6 GHz in addition to the resonance frequency of the fundamental wave (about 2.6 GHz).

[0097] Figure 17 It is a schematic diagram of the antenna device 202 of yet another comparison object. The antenna device 202 has a structure in which the excitation electrode 51 and the excitation electrode 52 are not connected to the antenna coupling element 10 as in the antenna device 100, and the connection portion of the excitation electrode 51 and the connection portion of the excitation electrode 52 cross and are connected to the substrate 40. In addition, in the antenna device 202, regarding Figure 1Constituent elements of the antenna device 100 shown that are the same are labeled with the same reference numerals and will not be described in detail repeatedly.

[0098] In the antenna device 202, excitation electrodes 51 and 52 are disposed at positions corresponding to the opening 25. The excitation electrode 51 is not connected to the antenna coupling element 10, but is connected to a power supply circuit 30 (not shown) through the wiring of the substrate 40, and power is supplied from the power supply circuit 30. On the other hand, the excitation electrode 52 is not connected to the antenna coupling element 10, crosses the connection portion of the excitation electrode 51, and is connected to the substrate 40 and connected to GND (grounded). That is, in the antenna device 202, the slot antenna constituted by the opening 25 and the excitation electrode 51 functions as a power supply antenna, the slot antenna constituted by the opening 25 and the excitation electrode 52 functions as a non-powered antenna, and the connection portions of the excitation electrodes 51 and 52 cross, and only the excitation electrode 51 and the excitation electrode 52 perform electric field coupling and do not perform magnetic field coupling.

[0099] Next, the characteristics of the antenna device 202 will be described. Figure 18 is a diagram showing the frequency characteristics of the reflection coefficient of the antenna device 202, which is another comparison object. In Figure 18 it, the horizontal axis is the frequency and the vertical axis is the reflection coefficient (return loss). Among them, the reflection coefficient D is the reflection coefficient of the antenna device 202.

[0100] In the reflection coefficient D, resonance occurs at the resonant frequency of the fundamental wave of the antenna device 202 at the mark M8 (about 2.5 GHz). Moreover, in the reflection coefficient D, resonance occurs at the resonant frequency of the higher harmonic of the antenna device 202 at the mark M9 (about 5.5 GHz). In the antenna device 202, by only causing resonance to occur near about 5.5 GHz, additional resonance points are not generated as in the antenna device 100, and resonance cannot be generated in a relatively wide frequency band including about 5.0 GHz to about 7.0 GHz.

[0101] Moreover, Figure 19 is a diagram showing the Smith chart of the antenna device 202, which is another comparison object. In Figure 19 the shown Smith chart, the lines of the target frequencies from 2 GHz to 8 GHz draw a relatively large circle near the mark M8 (about 2.5 GHz) and the mark M9 (about 5.5 GHz) respectively. Therefore, it is also judged from Figure 19 the shown Smith chart that the antenna device 202 causes resonance only at about 5.5 GHz in addition to the resonant frequency of the fundamental wave (about 2.5 GHz).

[0102] It is determined that simply adding a slot antenna that functions as a non-powered antenna to only the comparison object of the antenna devices 201 and 202 or to the slot antenna that functions as a powered antenna cannot increase the resonance points and cause resonance in a wide frequency band. Therefore, it is determined that in the antenna device 100, as an effect of combining the slot antenna including the excitation electrode 52 with the slot antenna including the excitation electrode 51 using the antenna combining element 10, it is to increase the resonance points and cause resonance in a wide frequency band.

[0103] [Impedance adjustment]

[0104] The antenna device 100 can change the size of the frequency band in which resonance is generated by changing the frequency characteristics near the additionally added resonance points by adjusting the impedance of the slot antenna including the excitation electrode 52 combined with the slot antenna including the excitation electrode 51 using the antenna combining element 10. As a method of adjusting the impedance of the slot antenna including the excitation electrode 52, for example, a method of changing the length of the excitation electrode 52 in the X direction and a method of changing the capacitance value of the capacitance element 60 connected between the coil L2 and the excitation electrode 52 are conceivable.

[0105] In the antenna device 100, the length of the excitation electrode 52 in the X direction is set to approximately half of the length of the excitation electrode 51 in the X direction, and the capacitance value of the capacitance element 60 is set to 0.3 pF to adjust the impedance. In this way, an explanation is given for the change in the frequency characteristics near the additionally added resonance points by adjusting the impedance. Specifically, the characteristics of the antenna device 100 in which the capacitance value of the capacitance element 60 is set to 0 (zero) F to adjust the impedance are explained.

[0106] Figure 20 It is a diagram showing the frequency characteristics of the reflection coefficient of the antenna device 100 in which the capacitance value of the capacitance element is changed. In Figure 20 the horizontal axis is the frequency and the vertical axis is the reflection coefficient (return loss). Here, the reflection coefficient E is the reflection coefficient of the antenna device 100 in which the capacitance value of the capacitance element 60 is changed to 0 (zero) F.

[0107] In the reflection coefficient E, resonance occurs at the resonance frequency of the fundamental wave of the antenna device 100 at the mark M11 (about 2.5 GHz). Moreover, in the reflection coefficient E, resonance occurs at the resonance frequencies of the higher harmonics of the antenna device 100 at the mark M12 (about 5.2 GHz) and the mark M13 (about 6.5 GHz). Therefore, even in the antenna device 100 in which the capacitance value of the capacitance element 60 is changed to 0 (zero) F, the resonance points can be increased. However, the reflection coefficient E can only cause resonance only near the mark M12 (about 5.2 GHz) and the mark M13 (about 6.5 GHz), and thus cannot be like Figure 5The shown reflection coefficient A causes resonance to occur within a relatively wide frequency band including approximately 5.0 GHz to approximately 7.0 GHz.

[0108] Moreover, Figure 21 is a Smith chart of the antenna device 100 in which the capacitance value of the capacitive element has been changed. In Figure 21 the shown Smith chart, the lines of the target frequencies from 2 GHz to 8 GHz depict circles near the respective markers M11 (approximately 2.5 GHz), M12 (approximately 5.2 GHz), and M13 (approximately 6.5 GHz). However, in Figure 21 the shown Smith chart, compared to the larger circles depicted near the respective markers M2 and M3 of the Smith chart in Figure 6 the circles depicted near the respective markers M12 (approximately 5.2 GHz) and M13 (approximately 6.5 GHz) are smaller. Therefore, it can also be judged from Figure 21 the shown Smith chart that the antenna device 100 in which the capacitance value of the capacitive element 60 is changed to 0 (zero) F can increase the resonance point but does not cause resonance within a relatively wide frequency band including approximately 5.0 GHz to approximately 7.0 GHz.

[0109] [Modification Example]

[0110] In the antenna device 100 described above, as Figure 3 shown, the excitation electrodes 51 and 52 are formed on the substrate 40 disposed on the conductor 20, and thus are disposed at positions different from the opening 25 in the Z direction. However, the excitation electrodes 51 and 52 may also be disposed at positions overlapping the opening 25 in the Z direction.

[0111] Figure 22 is a cross-sectional view of the modified antenna device 100A. In addition, in the antenna device 100A, the same reference numerals are given to the constituent elements that are the same as those of the Figures 1 to 3 shown antenna device 100, and detailed descriptions are not repeated. In the antenna device 100, as Figure 3 shown, the excitation electrodes 51 and 52 are formed on the surface of the substrate 40 on the side opposite to the surface of the substrate 40 in contact with the conductor 20. On the other hand, in the antenna device 100A, as Figure 22As shown, excitation electrodes 51 and 52 are formed on the surface of the substrate 40 that contacts the conductor 20. That is, in the antenna device 100A, in the Z direction, the opening 25 and the excitation electrodes 51 and 52 are arranged at overlapping positions. An example is shown here where the antenna coupling element 10 is arranged at a position that does not overlap with the conductor 20 in the Z direction. Alternatively, the antenna coupling element 10 can also be arranged at a position that overlaps with the opening 25 in the Z direction, similar to the excitation electrodes 51 and 52, and the excitation electrodes 51 and 52 can also be arranged on different surfaces of the substrate 40.

[0112] (Embodiment 2)

[0113] The antenna device 100 of Embodiment 1 has an opening 25 (slot) that is long in the X direction provided in the plate-shaped conductor 20, and excitation electrodes 51 and 52 are arranged at positions corresponding to the opening 25. The excitation electrodes 51 and 52 are arranged along the long side 25a of the opening 25. Therefore, the excitation electrodes 51 and 52 are capacitively coupled (electric field coupling) with the peripheral portion of the opening 25, and thus are excited as an antenna. In the antenna device of Embodiment 2, the available frequency band is broadened. Therefore, an antenna that is excited by causing current to flow through the peripheral portion of the opening is combined with an antenna that is excited by capacitively coupling the excitation electrode with the peripheral portion of the opening.

[0114] Figure 23 is a schematic diagram of an electronic device including the antenna device 100B of Embodiment 2. As Figure 23 shown, the electronic device includes: an antenna device 100B; a power supply circuit 30 that supplies power to the excitation electrode 51a (first excitation electrode); and a housing 300 that houses the antenna device 100B and the power supply circuit 30. In addition, in the electronic device including the antenna device 100B, for components that are the same as those of the electronic device including the Figure 1 antenna device 100 shown, the same reference numerals are used and detailed descriptions are not repeated.

[0115] The antenna device 100B has an opening 25 (slot) that is long in the X direction provided in the plate-shaped conductor 20, and an excitation electrode 51a (excitation conductor, feed line, or simply referred to as a microstrip line) is arranged near the opening 25. By causing the excitation electrode 51a to act as a capacitive power supply element with respect to the opening 25, the excitation electrode 51a is capacitively coupled (electric field coupling) with the peripheral portion of the opening 25, and thus the antenna device 100B is excited as a slot antenna.

[0116] In addition, the excitation electrode 51a is electrically connected to one end (first external electrode 11) of the coil L1 of the antenna coupling element 10 mounted on the substrate 40. As Figure 23As shown, the excitation electrode 51a is connected to the power supply circuit 30 via the antenna coupling element 10, and power is supplied from the power supply circuit 30. That is, the slot antenna composed of the opening 25 and the excitation electrode 51a functions as a power supply antenna. In addition, the other end (the second external electrode 12) of the coil L1 of the antenna coupling element 10 is electrically connected to the power supply circuit 30.

[0117] The antenna device 100B is different from the antenna device 100. The excitation electrode 52 is not provided, and one end (the fourth external electrode 14) of the coil L2 of the antenna coupling element 10 is connected to the GND electrode 41 (substrate electrode) of the substrate 40. By connecting one end of the coil L2 to the GND electrode 41, the current from the power supply circuit 30 flows to the peripheral portion of the opening 25 via the coil L1 that magnetically couples with the coil L2, thereby exciting the antenna device 100B. As a result, in addition to the resonance frequency of the slot antenna excited by the excitation electrode 51a, the antenna device 100B has the resonance frequency of the antenna excited by the connection between the antenna coupling element 10 and the GND electrode 41, and can widen the bandwidth of the available frequency band.

[0118] In addition, the other end (the third external electrode 13) of the coil L2 may or may not be connected to the substrate 40, but is not electrically connected to an electrode such as the GND electrode. By connecting the other end of the coil L2 to the substrate 40, the mounting strength of the antenna coupling element 10 with respect to the substrate 40 is improved.

[0119] Figure 23 The GND electrode 41 shown is provided in a strip shape in the X direction of the substrate 40 parallel to the opening 25, but is not limited to this shape. The GND electrode 41 may be any shape that can connect one end of the power supply circuit 30 and one end of the coil L2. In addition, the GND electrode 41 may be composed of a part electrically connected to one end of the power supply circuit 30 and a part electrically connected to one end of the coil L2, and any part may be electrically connected to the conductor 20 disposed on the housing 300.

[0120] By connecting one end of the coil L2 to the GND electrode 41, the current of the power supply circuit 30 flows to the peripheral portion of the opening 25 via the magnetically coupled coil L1, thereby exciting the antenna device 100B as an antenna. Therefore, due to the relationship between the position where one end of the power supply circuit 30 is electrically connected to the GND electrode 41 and the position where one end of the coil L2 is electrically connected to the GND electrode 41, the current flowing in the peripheral portion of the opening 25 changes, and the resonance frequency of the antenna excited by this current also changes.

[0121] The simulation results of the antenna device 100B will be described. Figure 24 It is a diagram showing the frequency characteristics of the reflection coefficient of the antenna device 100B according to the second embodiment.Figure 25 is a diagram showing the antenna efficiency of the antenna device 100B of Embodiment 2. In Figure 24 , the horizontal axis is the frequency and the vertical axis is the reflection coefficient (return loss). In Figure 25 , the horizontal axis is the frequency and the vertical axis is the antenna efficiency.

[0122] Figure 24 The shown reflection coefficient F represents the reflection coefficient of the antenna device 100B, and the reflection coefficient G represents the reflection coefficient of the slot antenna without the antenna coupling element. In the reflection coefficient G, resonance occurs at the resonance frequency of the slot antenna excited by the excitation electrode 51a at approximately 2.3 GHz. Moreover, in the reflection coefficient F, resonance occurs at the resonance frequency of the antenna excited by connecting the antenna coupling element 10 and the GND electrode 41 at approximately 3.0 GHz. Therefore, Figure 25 the antenna efficiency H of the shown antenna device 100B maintains a high efficiency in the range of approximately 2.3 GHz to approximately 3.0 GHz.

[0123] In Figure 24 and Figure 25 , the reflection coefficient G and the antenna efficiency I of the slot antenna excited only by the excitation electrode are shown as comparison objects. The reflection coefficient G resonates only at the resonance frequency of the slot antenna excited by the excitation electrode at 2.2 GHz, and there are no other resonance points. Therefore, it can be seen that: for Figure 25 the shown antenna efficiency I, the efficiency decreases as the frequency is greater than approximately 2.4 GHz.

[0124] As can be seen from the simulation results of Figure 24 and Figure 25 , in addition to the slot antenna excited by the excitation electrode 51a, the antenna device 100B additionally uses the antenna excited by the connection between the antenna coupling element 10 and the GND electrode 41, so that the number of resonance points can be increased and resonance can be generated in a relatively wide frequency band including approximately 2.3 GHz to approximately 3.0 GHz. In addition, the antenna device 100B can obtain good antenna efficiency in a wide frequency band.

[0125] [Modification Example 1]

[0126] In Figure 23 the shown antenna device 100B, the position where one end of the power supply circuit 30 is electrically connected to the GND electrode 41 and the position where one end of the coil L2 is electrically connected to the GND electrode 41 are on the same side of the opening 25. In Modification Example 1, an antenna device is described in which the position where one end of the power supply circuit is electrically connected to the GND electrode and the position where one end of the coil L2 is electrically connected to the GND electrode are on different sides of the opening 25.

[0127] Figure 26This is a schematic diagram of an electronic device including the antenna device 100C which is a modified example 1 of Embodiment 2. As Figure 26 shown, the electronic device includes: an antenna device 100C; a power supply circuit 30 that supplies power to the excitation electrode 51a (excitation electrode); and a housing 300 that houses the antenna device 100C and the power supply circuit 30. In addition, in the electronic device including the antenna device 100C, for the components that are the same as those of the electronic device including the Figure 1 antenna device 100 shown as Figure 23 and the antenna device 100B shown as

[0128] the same reference numerals are assigned to the same components and detailed descriptions will not be repeated.

[0129] In the antenna device 100C, an opening 25 that is longer in the X direction is provided in the plate-shaped conductor 20, and the excitation electrode 51a is disposed near the opening 25. That is, by the excitation electrode 51a acting as a capacitive power supply element with respect to the opening 25, the excitation electrode 51a performs electric field coupling (capacitive coupling) with the peripheral portion of the opening 25, so that the antenna device 100C is excited as a slot antenna. The slot antenna composed of the opening 25 and the excitation electrode 51a functions as a power supply antenna.

[0130] Figure 26 The GND electrode 42 shown as Figure 26 has an L shape including a portion in the X direction of the substrate 40 provided parallel to the opening 25 and a portion in the Y direction of the substrate 40 provided overlapping the opening 25 partially. When viewed from the Z direction, the opening 25 partially overlaps with the GND electrode 42. Therefore, the opening of the slot antenna becomes the portion obtained by removing the portion where the GND electrode 42 partially overlaps from the opening 25. In addition, in

[0131] The position where one end of the power supply circuit 30 of the antenna device 100C is electrically connected to the GND electrode 42 and the position where one end of the coil L2 is electrically connected to the GND electrode 42 are set on different sides of the opening 25. Specifically, one end of the power supply circuit 30 is set on the X-direction side of the GND electrode 42, and one end of the coil L2 is set on the Y-direction side of the GND electrode 42. Therefore, in the antenna device 100C, by separating the position where one end of the coil L2 is electrically connected to the GND electrode 42 from the position where one end of the power supply circuit 30 is electrically connected to the GND electrode 42, the resonance of the two antennas is made non-interfering, thereby improving the antenna characteristics.

[0132] In addition, the GND electrode 42 may also be configured by being divided into an electrode electrically connected to one end of the power supply circuit 30 and an electrode electrically connected to one end of the coil L2, and any one of the electrodes is electrically connected to the conductor 20 and the housing 300, and may be set on different sides of the opening 25.

[0133] [Modification Example 2]

[0134] In Figure 23 In the antenna device 100B shown, one end of the power supply circuit 30 and one end of the coil L2 are electrically connected to the GND electrode 41. In Modification Example 2, an antenna device with an increased portion electrically connected to the GND electrode will be described.

[0135] Figure 27 is a schematic diagram of an electronic device including the antenna device 100D of Modification Example 2 of Embodiment 2. As Figure 27 shown, the electronic device includes: an antenna device 100D; a power supply circuit 30 that supplies power to the excitation electrode 51a (first excitation electrode); and a housing 300 that houses the antenna device 100D and the power supply circuit 30. In addition, in the electronic device including the antenna device 100D, for the components that are the same as those of the electronic devices including Figure 1 the antenna device 100 shown and Figure 23 the antenna device 100B shown, the same reference numerals are used for the same components, and detailed descriptions will not be repeated.

[0136] The antenna device 100D has an opening 25 that is long in the X direction provided in the plate-shaped conductor 20, and an excitation electrode 51b is disposed at a position corresponding to the opening 25. That is, the antenna device 100D is excited as a slot antenna by the excitation electrode 51b acting as a capacitive power supply element with respect to the opening 25 and the excitation electrode 51b performing electric field coupling (capacitive coupling) with the peripheral portion of the opening 25. The slot antenna formed by the opening 25 and the excitation electrode 51b functions as a power supply antenna.

[0137] The excitation electrode 51b and Figure 23Unlike the excitation electrode 51a shown, it has a shape that is longer in the X direction along the opening 25, with one end electrically connected to one end of the coil L1 (the first external electrode 11) and the other end electrically connected to the GND electrode 41 of the substrate 40.

[0138] In addition, one end of the coil L2 (the fourth external electrode 14) of the antenna device 100D is electrically connected to the GND electrode 41 of the substrate 40, and the other end of the coil L2 (the third external electrode 13) is also electrically connected to the GND electrode 41. By connecting the coil L2 to the GND electrode 41, the current from the power supply circuit 30 flows through the coil L1 that is magnetically coupled to the coil L2 to the peripheral portion of the opening 25, thereby exciting the antenna device 100D.

[0139] The antenna device 100D is as shown in Figure 27 Not only one end of the power supply circuit 30 and one end of the coil L2, but also one end of the coil L1 and the other end of the coil L2 are electrically connected to the GND electrode 41. Therefore, compared with the antenna device 100B shown in Figure 23 By increasing the starting points of the current flowing to the GND electrode 41, the antenna device 100D can increase the paths for the current to flow from the power supply circuit 30 through the antenna coupling element 10 to the peripheral portion of the opening 25, thereby broadening the bandwidth. In addition, the structure described in Modification Example 1 and the structure described in Modification Example 2 can be combined. Also, in Figure 27 It is depicted by differentiating the excitation electrode 51b and the line connecting the excitation electrode 51b to the GND electrode 41. In fact, there are also cases where the boundary is not clear.

[0140] [Modification Example 3]

[0141] Figure 23 The antenna device 100B shown in

[0142] Figure 28 constitutes a slot antenna excited by the excitation electrode 51a powered by the power supply circuit 30 and a slot antenna without power supply by using the antenna coupling element 10. In Modification Example 3, an antenna device that does not use the antenna coupling element 10 and constitutes a powered slot antenna and a non-powered slot antenna will be described. Figure 28 is a schematic diagram of an electronic device including the antenna device 100E of Modification Example 3 of Embodiment 2. As shown in Figure 1 The electronic device includes: an antenna device 100E; a power supply circuit 30 that supplies power to the excitation electrode 51a (the first excitation electrode); and a housing 300 that houses the antenna device 100E and the power supply circuit 30. In addition, in an electronic device including the antenna device 100E, regarding the one including Figure 23The components of the electronic device of the antenna device 100B shown are denoted by the same reference numerals for the same components and will not be described in detail repeatedly.

[0143] The antenna device 100E has an opening 25 that is longer in the X direction provided in a plate-like conductor 20, and an excitation electrode 51a is disposed near the opening 25. That is, the excitation electrode 51a operates as a capacitive power supply element with respect to the opening 25, and the excitation electrode 51a performs electric field coupling (capacitive coupling) with the peripheral portion of the opening 25, so that the antenna device 100E is excited as a slot antenna. The slot antenna constituted by the opening 25 and the excitation electrode 51a functions as a power supply antenna.

[0144] In addition, the antenna device 100E has an excitation electrode 52a disposed near the excitation electrode 51a, and one end of the excitation electrode 52a is connected to the GND electrode 41 (substrate electrode) of the substrate 40. The excitation electrode 52a has an L shape including a portion disposed parallel to the excitation electrode 51a (in the Y direction) and a portion disposed parallel to the GND electrode 41 (in the X direction). In the portion where the excitation electrode 51a and the excitation electrode 52a are disposed in parallel, electromagnetic field coupling occurs between the excitation electrodes, and thus, due to the current flowing from the power supply circuit 30 to the excitation electrode 51a, current flows to the excitation electrode 52a.

[0145] By connecting one end of the excitation electrode 52a to the GND electrode 41, the current from the power supply circuit 30 flows to the peripheral portion of the opening 25 via the portion where the excitation electrode 51a and the excitation electrode 52a are disposed in parallel, so that the antenna device 100E is excited. Thus, the antenna device 100E can constitute a slot antenna powered by the power supply circuit 30 and a non-powered slot antenna without using the antenna coupling element 10, and the manufacturing cost can be reduced. In addition, the structures described in Modification Examples 1 and 2 can be combined with the structure described in Modification Example 3.

[0146] [Solution]

[0147] (1) An antenna device, comprising:

[0148] A plate-like conductor having an opening;

[0149] A first excitation electrode and a second excitation electrode disposed at positions corresponding to the opening;

[0150] A first coil having one end electrically connected to the first excitation electrode and the other end connected to a power supply circuit; and

[0151] A second coil having one end electrically connected to the second excitation electrode,

[0152] The first coil and the second coil are arranged at positions where magnetic field coupling occurs.

[0153] Thus, the antenna device of the present disclosure can add resonance points for broadbanding the available frequency band by connecting the first excitation electrode and the second excitation electrode arranged at positions corresponding to the opening to the first coil and the second coil for magnetic field coupling respectively.

[0154] (2) The antenna device according to (1), wherein

[0155] The first excitation electrode and the second excitation electrode are arranged at positions overlapping the opening when observing the opening from above.

[0156] (3) The antenna device according to (2), wherein

[0157] The antenna device further includes a substrate arranged between the first excitation electrode, the second excitation electrode and the conductor.

[0158] (4) The antenna device according to any one of (1) to (3), wherein

[0159] The opening has a rectangular shape with a second side shorter than a first side,

[0160] The first excitation electrode and the second excitation electrode are strip-shaped and extend along the first side.

[0161] (5) The antenna device according to (4), wherein

[0162] A first direction in which the first excitation electrode extends and a second direction in which the second excitation electrode extends are opposite along the first side.

[0163] (6) The antenna device according to any one of (1) to (5), wherein

[0164] The antenna device further includes a capacitance element connected in series between the second coil and the second excitation electrode.

[0165] (7) The antenna device according to any one of (1) to (6), wherein

[0166] The antenna coupling element including the first coil and the second coil includes:

[0167] An insulator;

[0168] A first external electrode, a second external electrode, a third external electrode, and a fourth external electrode formed on the surface of the insulator; and

[0169] The first coil and the second coil formed by a plurality of conductor patterns in the insulator,

[0170] The plurality of conductor patterns constituting the first coil includes a conductor pattern electrically connected to the first external electrode or the second external electrode.

[0171] The plurality of conductor patterns constituting the second coil includes a conductor pattern electrically connected to the third external electrode or the fourth external electrode.

[0172] When viewed in the stacking direction of the insulator, the opening of the first coil and the opening of the second coil at least partially overlap.

[0173] (8) The antenna device according to (7), wherein

[0174] The first excitation electrode is electrically connected to the first external electrode of the antenna coupling element.

[0175] The power supply circuit is electrically connected to the second external electrode of the antenna coupling element.

[0176] The second excitation electrode is electrically connected to the third external electrode of the antenna coupling element.

[0177] The fourth external electrode of the antenna coupling element is grounded.

[0178] (9) The antenna device according to any one of (7) or (8), wherein

[0179] The first coil includes:

[0180] At least two or more layers of first conductor patterns electrically connected to the first external electrode; and

[0181] A second conductor pattern stacked relative to the first conductor pattern and electrically connected to the second external electrode.

[0182] The layers of the first conductor pattern are connected in parallel to each other, and the second conductor pattern is connected in series with the first conductor pattern.

[0183] The second coil includes:

[0184] At least two or more layers of third conductor patterns electrically connected to the third external electrode; and

[0185] A fourth conductor pattern stacked relative to the third conductor pattern and electrically connected to the fourth external electrode.

[0186] The layers of the third conductor pattern are connected in parallel to each other, and the fourth conductor pattern is connected in series with the third conductor pattern.

[0187] The first coil and the second coil are arranged in the insulator such that the second conductor pattern and the fourth conductor pattern face each other in the stacking direction.

[0188] (10) An electronic device, wherein the electronic device includes:

[0189] The antenna device according to any one of (1) to (9);

[0190] A power supply circuit that supplies power to the first excitation electrode; and

[0191] A housing that houses the antenna device and the power supply circuit.

[0192] (11) An antenna device, wherein the antenna device includes:

[0193] A plate-shaped conductor having an opening;

[0194] An excitation electrode disposed at a position corresponding to the opening;

[0195] A first coil, one end of which is electrically connected to the excitation electrode and the other end of which is connected to the power supply circuit; and

[0196] A second coil, one end of which is electrically connected to a substrate electrode electrically connected to the conductor,

[0197] The first coil and the second coil are disposed at positions where magnetic field coupling occurs.

[0198] Thus, the antenna device of the present disclosure can add resonance points in order to widen the available frequency band by causing magnetic field coupling between the first coil having one end electrically connected to the excitation electrode and the other end connected to the power supply circuit and the second coil having one end electrically connected to the substrate electrode electrically connected to the conductor.

[0199] (12) The antenna device according to (11), wherein

[0200] The substrate electrode is also electrically connected to the other end of the second coil.

[0201] (13) The antenna device according to (11) or (12), wherein

[0202] The substrate electrode is provided along at least two sides of the opening,

[0203] The power supply circuit is electrically connected to a portion of the substrate electrode provided along the first side of the opening,

[0204] One end of the second coil is electrically connected to a portion of the substrate electrode provided along the second side of the opening different from the first side.

[0205] (14) The antenna device according to any one of (11) to (13), wherein

[0206] The antenna coupling element including the first coil and the second coil includes:

[0207] An insulator;

[0208] The first external electrode, the second external electrode, the third external electrode, and the fourth external electrode formed on the surface of the insulator; and

[0209] The first coil and the second coil, which are formed by a plurality of conductor patterns in the insulator,

[0210] The plurality of conductor patterns forming the first coil include a conductor pattern electrically connected to the first external electrode or the second external electrode,

[0211] The plurality of conductor patterns forming the second coil include a conductor pattern electrically connected to the third external electrode or the fourth external electrode,

[0212] When viewed from the stacking direction of the insulator, the opening of the first coil and the opening of the second coil at least partially overlap.

[0213] (15) An electronic device, wherein the electronic device includes:

[0214] (14) The antenna device described above;

[0215] A power supply circuit that supplies power to the excitation electrode; and

[0216] A housing that houses the antenna device and the power supply circuit.

[0217] It should be considered that the embodiments disclosed herein are illustrative in all aspects and not restrictive. The scope of the present invention is represented by the claims and not by the above description, and is intended to include all modifications within the meaning and scope equivalent to the claims.

[0218] Explanation of reference numerals

[0219] 10. Antenna coupling element; 11. First external electrode; 12. Second external electrode; 13. Third external electrode; 14. Fourth external electrode; 20. Conductor; 21, 21a, 21b. First conductor pattern; 22, 22A. Second conductor pattern; 23, 23a, 23b. Third conductor pattern; 24, 24A. Fourth conductor pattern; 25. Opening; 31, 32. Via conductor; 30. Power supply circuit; 40. Substrate; 51, 52. Excitation electrode; 60. Capacitor element; 100, 100A, 200, 201, 202. Antenna device; 300. Housing.

Claims

1. An antenna device, wherein, The antenna device includes: A plate-shaped conductor having an opening; A first excitation electrode and a second excitation electrode disposed at positions corresponding to the opening; A first coil having one end electrically connected to the first excitation electrode and the other end connected to a power supply circuit; and A second coil having one end electrically connected to the second excitation electrode, The first coil and the second coil are disposed at positions where magnetic field coupling occurs.

2. The antenna device according to claim 1, wherein The first excitation electrode and the second excitation electrode are disposed at positions overlapping the opening when the opening is viewed from above.

3. The antenna device according to claim 2, wherein The antenna device further includes a substrate disposed between the first excitation electrode, the second excitation electrode, and the conductor.

4. The antenna device according to any one of claims 1 to 3, wherein The opening has a rectangular shape with a second side shorter than a first side, The first excitation electrode and the second excitation electrode are strip-shaped and extend along the first side.

5. The antenna device according to claim 4, wherein A first direction in which the first excitation electrode extends is opposite to a second direction in which the second excitation electrode extends along the first side.

6. The antenna device according to any one of claims 1 to 5, wherein The antenna device further includes a capacitance element connected in series between the second coil and the second excitation electrode.

7. The antenna device according to any one of claims 1 to 6, wherein The antenna combining element including the first coil and the second coil includes: An insulator; A first external electrode, a second external electrode, a third external electrode, and a fourth external electrode formed on the surface of the insulator; And The first coil and the second coil formed by a plurality of conductor patterns in the insulator, The plurality of conductor patterns constituting the first coil include a conductor pattern electrically connected to the first external electrode or the second external electrode, The plurality of conductor patterns constituting the second coil include a conductor pattern electrically connected to the third external electrode or the fourth external electrode, When viewed from the stacking direction of the insulator, the opening of the first coil and the opening of the second coil at least partially overlap.

8. The antenna device according to claim 7, wherein The first excitation electrode is electrically connected to the first external electrode of the antenna combining element, The power supply circuit is electrically connected to the second external electrode of the antenna combining element, The second excitation electrode is electrically connected to the third external electrode of the antenna combining element, The fourth external electrode of the antenna combining element is grounded.

9. The antenna device according to claim 7 or 8, wherein The first coil includes: At least two or more layers of first conductor patterns electrically connected to the first external electrode; and A second conductor pattern stacked relative to the first conductor pattern and electrically connected to the second external electrode, Each layer of the first conductor pattern is connected in parallel to each other, and the second conductor pattern is connected in series with the first conductor pattern. The second coil includes: At least two or more layers of a third conductor pattern, which is electrically connected to the third external electrode; and A fourth conductor pattern, which is stacked relative to the third conductor pattern layer and is electrically connected to the fourth external electrode. Each layer of the third conductor pattern is connected in parallel to each other, and the fourth conductor pattern is connected in series with the third conductor pattern. The first coil and the second coil are arranged in the insulator such that the second conductor pattern and the fourth conductor pattern face each other in the stacking direction.

10. An electronic device, wherein, This electronic device includes: The antenna device according to any one of claims 1 to 9; The power supply circuit, which supplies power to the first excitation electrode; and A housing, which houses the antenna device and the power supply circuit.

11. An antenna device, wherein, This antenna device includes: A plate-shaped conductor, which has an opening; An excitation electrode, which is arranged at a position corresponding to the opening; A first coil, one end of which is electrically connected to the excitation electrode, and the other end of which is connected to the power supply circuit; and A second coil, one end of which is electrically connected to a substrate electrode electrically connected to the conductor. The first coil and the second coil are arranged at positions where magnetic field coupling occurs.

12. The antenna device according to claim 11, wherein The substrate electrode is also electrically connected to the other end of the second coil.

13. The antenna device according to claim 11 or 12, wherein The substrate electrode is arranged along at least two sides of the opening, The power supply circuit is electrically connected to a part of the substrate electrode arranged along the first side of the opening, One end of the second coil is electrically connected to a part of the substrate electrode arranged along the second side of the opening different from the first side.

14. The antenna device according to any one of claims 11 to 13, wherein The antenna coupling element including the first coil and the second coil includes: An insulator; A first external electrode, a second external electrode, a third external electrode, and a fourth external electrode formed on the surface of the insulator; And The first coil and the second coil formed by a plurality of conductor patterns in the insulator. The plurality of conductor patterns constituting the first coil include a conductor pattern electrically connected to the first external electrode or the second external electrode. The plurality of conductor patterns constituting the second coil include a conductor pattern electrically connected to the third external electrode or the fourth external electrode. When viewed from the stacking direction of the insulator, the opening of the first coil and the opening of the second coil at least partially overlap.

15. An electronic device, wherein, This electronic device includes: The antenna device according to claim 14; The power supply circuit, which supplies power to the excitation electrode; and A housing, which houses the antenna device and the power supply circuit.

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