JP2016181755A - Antenna device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an antenna device that can be miniaturized, in an antenna device having horizontal plane non-directivity.SOLUTION: A first annular pattern 60 forms an electrostatic capacitance and an inductance defined depending on an interval from a power feeding pattern 30. A connection part 70 has an inductance depending on its length. The inductance of the connection part 70, and the inductance and the electrostatic capacitance of the first annular pattern 60 are connected in series to form a series circuit part 1, in an equivalent circuit of an antenna device 100. This series circuit part 1 is connected in parallel to the electrostatic capacitance resulting from the power feeding pattern. By setting a resonance frequency Fa of the series circuit part 1 to a frequency higher than a target frequency F, the series circuit part 1 acts as a capacitive reactance at the target frequency, and its equivalent capacitive value is added to the electrostatic capacitance resulting from the power feeding pattern. Thereby, an electrostatic capacitance required for the power feeding pattern 30 is suppressed.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an antenna device having a flat plate structure.

  In Patent Document 1, a flat metal pattern (referred to as a ground pattern) that functions as a ground is formed on one surface of a flat plate member made of a dielectric, and at the position facing the ground plate on the other surface of the flat plate member. An antenna device in which a flat metal pattern (referred to as a power feeding pattern) having a predetermined area is formed is disclosed. The power supply pattern is provided with a power supply point at an arbitrary position, and the ground pattern and the power supply pattern are electrically connected by a short-circuit portion realized using a through via.

  In the antenna device of Patent Document 1, parallel resonance is generated at a frequency corresponding to the capacitance and the inductance by the capacitance formed between the ground plane and the opposing conductor plate and the inductance included in the short-circuit portion. . Then, a radio wave (vertically polarized wave) having a desired frequency is transmitted (or received) by a vertical electric field generated between the opposing conductor plate and the ground plane due to parallel resonance. This antenna device operates as an omnidirectional antenna on a plane (horizontal plane) parallel to the flat plate member.

  The capacitance formed between the ground pattern and the power supply pattern is determined according to the area of the power supply pattern. For this reason, by adjusting the area of the power feeding pattern, the frequency to be transmitted / received (target frequency) in the antenna device can be set to a desired frequency.

JP 2014-107746 A

  According to the configuration of Patent Document 1, the area of the power feeding pattern needs to be an area for forming a capacitance according to the target frequency. Therefore, if the target frequency is lowered, a larger capacitance is required, and thus the antenna area is increased. On the other hand, further miniaturization of the antenna device is desired.

  The present invention has been made based on this situation, and an object of the present invention is to provide an antenna device that can be reduced in size in an antenna device having horizontal omnidirectionality.

  In order to achieve the object, the present invention provides a ground pattern (20) that is a flat conductor disposed on a first plane, and the ground pattern on a second plane parallel to the first plane. A flat conductor disposed so as to oppose the power supply pattern (30) connected to the power supply line, and a short circuit that electrically connects the power supply pattern and the ground pattern at the center of the power supply pattern A first annular pattern (60) realized using a conductor formed in a ring shape so as to have a predetermined distance from an edge of the feeding pattern in the second plane, And a connection portion (70) for electrically connecting the power feeding pattern and the first annular pattern.

  In the above configuration, the short-circuit portion has a predetermined inductance corresponding to its length, and the power feeding pattern forms a capacitance corresponding to its area with the ground pattern. In the equivalent circuit of the antenna device, the capacitance derived from the power feeding pattern is connected in parallel with the inductance derived from the short-circuit portion.

  The first annular pattern forms a capacitance and an inductance that are determined according to the distance from the power feeding pattern, and the connection portion has an inductance corresponding to the length. The inductance included in each of the connection portion and the first annular pattern and the electrostatic capacitance derived from the first annular pattern are connected in series in the equivalent circuit of the antenna device to form a series circuit portion. This series circuit unit is connected in parallel to the capacitance derived from the power feeding pattern.

  Here, when the resonance frequency of the series circuit section is higher than the frequency to be transmitted / received by the antenna device (target frequency), it behaves as capacitive reactance, and its equivalent capacitance component Are connected in parallel to the capacitance derived from the power feeding pattern.

  Therefore, in the conventional configuration disclosed in Patent Document 1, it is necessary that the power supply pattern has an area for forming a capacitance according to the target frequency. The total of the electrostatic capacitance derived from the pattern and the equivalent capacitance component of the series circuit portion only needs to be an electrostatic capacitance according to the target frequency. That is, according to the said structure, a power feeding pattern can be made smaller than the power feeding pattern of a conventional structure.

  In addition, the size of the equivalent capacitance component of the series circuit unit is determined according to the difference between the resonance frequency of the series circuit unit and the target frequency, and as the target frequency becomes closer to the resonance frequency of the series circuit unit, the capacitance value Becomes bigger.

  And the amount of reduction of the area of the power feeding pattern is more than the area required to provide the first annular pattern or the like forming the series circuit part around the power feeding pattern by adjusting the resonance frequency of the series circuit part. Can be large enough.

  The principle when transmitting and receiving radio waves of the target frequency is the same as that of the comparative configuration, and operates as a non-directional antenna in the first plane direction as in the comparative configuration. Therefore, when the antenna device is installed in a posture in which the first plane is horizontal, the antenna device operates as an omnidirectional antenna on the horizontal plane.

  Therefore, according to the above configuration, it is possible to reduce the size of the antenna device having omnidirectionality in the horizontal plane.

  In addition, the code | symbol in the parenthesis described in the claim shows the correspondence with the specific means as described in embodiment mentioned later as one aspect, Comprising: The technical scope of this invention is limited is not.

It is a top view of antenna device 100 in a 1st embodiment. It is sectional drawing of the antenna apparatus 100 in the II-II line | wire shown in FIG. 2 is an equivalent circuit diagram of the antenna device 100. FIG. 4 is a graph showing a relationship between impedance and frequency of the series circuit unit 1. 3 is a graph showing the relationship between the equivalent capacitance value of the series circuit section 1 and the frequency. 3 is an equivalent circuit diagram of the antenna device 100 at a target frequency F. FIG. 3 is an equivalent circuit diagram of the antenna device 100 at a target frequency F. FIG. 3 is a diagram illustrating the directivity of the antenna device 100. FIG. 3 is a diagram illustrating the directivity of the antenna device 100. FIG. It is a figure which shows the structure of the antenna apparatus 100X as a comparison structure. It is an equivalent circuit diagram of the antenna device 100X. It is a top view of antenna device 100A in modification 1-1. It is a top view of the antenna apparatus 200 in 2nd Embodiment. It is sectional drawing of the antenna apparatus 200 in the XIV-XIV line | wire shown in FIG. 3 is an equivalent circuit diagram of the antenna device 200. FIG. 4 is a graph showing the relationship between the equivalent capacitance value of the first series circuit section 1 and the frequency. 4 is a graph showing a relationship between an equivalent capacitance value of the second series circuit unit 2 and a frequency. 3 is an equivalent circuit diagram of the antenna device 200 at a target frequency F. FIG. 3 is an equivalent circuit diagram of the antenna device 200 at a target frequency F. FIG. It is a graph which shows the relationship between the equivalent capacitance value of the 3rd series circuit part 3 shown in FIG. 19, and a frequency. 3 is an equivalent circuit diagram of the antenna device 200 at a target frequency F. FIG. 3 is an equivalent circuit diagram of the antenna device 200 at a target frequency F. FIG. It is the simulation result showing the mode of the magnetic field in an element layer in case the antenna apparatus 200 is carrying out parallel resonance. It is the simulation result showing the electric field distribution in case the antenna apparatus 200 is carrying out parallel resonance. It is a figure for demonstrating the structure of the antenna apparatus 200 in the modification 2-1. It is a figure for demonstrating the structure of the antenna apparatus 200 in the modification 2-1. It is a top view of the antenna device 200 in Modification 2-3. It is a top view of the antenna device 200 in Modification 2-4. It is a top view of the antenna device 200 in Modification 2-5. It is a top view of the antenna device 200 in Modification 2-8. It is a top view of the antenna device 200 in Modification 2-9. It is a top view of antenna device 200A in modification 2-11. It is a top view of antenna apparatus 200B in Modification 2-12. It is sectional drawing of the antenna apparatus 200B in the dashed-dotted line shown in FIG. It is a top view of antenna apparatus 200C in Modification 2-13. FIG. 36 is an enlarged view of the vicinity of the connecting portion 70 in the cross section of the antenna device 200 </ b> C along the alternate long and short dash line shown in FIG.

<First Embodiment>
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a top view illustrating an example of a schematic configuration of an antenna device 100 according to the present embodiment. 2 is a cross-sectional view of the antenna device 100 taken along the line II-II shown in FIG. As shown in FIGS. 1 and 2, the antenna device 100 includes a support substrate 10, a ground pattern 20, a power feeding pattern 30, a short circuit part 40, a power feeding part 50, an annular pattern 60, and a connection part 70.

  The antenna device 100 is used, for example, in a vehicle, and is used for transmission / reception (or transmission or reception) of radio waves of a predetermined frequency (for example, 750 MHz). The frequency of the radio wave to be transmitted / received (the target frequency F) may be designed as appropriate, and is 760 MHz here.

  The antenna device 100 is connected to a radio (not shown) via a coaxial cable, for example, and signals received by the antenna device 100 are sequentially output to the radio. The wireless device uses a signal received by the antenna device 100 and supplies high-frequency power corresponding to the transmission signal to the antenna device 100. In the present embodiment, description will be made on the assumption that a coaxial cable is employed as a feed line to the antenna device 100, but other known feed lines such as a feeder line may be used.

  Note that the antenna device 100 is preferably placed so that the ground pattern 20 is also substantially horizontal when the vehicle is in a horizontal posture, for example, on the roof of the vehicle. In this case, the antenna device 100 forms the same directivity for all horizontal directions as will be described later. That is, the antenna device 100 functions as an omnidirectional antenna on a horizontal plane. Hereinafter, a specific configuration of the antenna device 100 will be described.

  The support substrate 10 is a plate-like member having a predetermined thickness made of an electrically insulating material (that is, a dielectric) such as resin. A ground pattern 20 is formed on one surface (lower surface) of the support substrate 10, and a power feeding pattern 30, an annular pattern 60, and a connection portion 70 are formed on the other surface (upper surface). . As a result, the antenna device 100 as a whole has a flat plate structure. In the antenna device 100, the side on which the power feeding pattern 30 and the like are provided is relatively upper, and the side on which the ground pattern 20 is provided is relatively lower.

  In the present embodiment, the support substrate 10 is a plate-like member having a uniform resin filling density, but the structure of the support substrate 10 is not limited thereto. The support substrate 10 only needs to be able to support the power supply pattern 30, the layer including the annular pattern 60, and the connection portion 70 (element layer) and the ground pattern so as to face each other with a predetermined interval. The appropriate structure may be designed as appropriate.

  For example, the support substrate 10 may have a structure including one or a plurality of hollow portions (hollow portions). For example, the support substrate 10 may have a so-called honeycomb structure in which the outline of the hollow portion in the cross section in the direction perpendicular to the thickness direction is a hexagon. Further, the hollow part in the cross section perpendicular to the thickness direction may have a triangular, quadrangular, or circular shape. Of course, the structure of the support substrate 10 is not limited to the above-described example.

  The resin used as the support substrate 10 is preferably a resin having a small dielectric loss tangent, such as a fluororesin or polypropylene. Further, the separation between the element layer and the ground pattern 20 may be designed as appropriate, for example, 0.8 mm or 1.0 mm. In FIG. 1, the lower surface of the support substrate 10 corresponds to an example of a first plane recited in the claims, and the upper surface corresponds to an example of a second plane recited in the claims.

  The ground pattern 20 is an elliptical plate-like member (including foil) made of a conductor such as copper. The ground pattern 20 is electrically connected to the outer conductor of the coaxial cable to form a ground potential (ground potential) in the antenna device 100. Here, the outline of the ground pattern 20 has a shape that coincides with an outer peripheral portion 62 of an annular pattern 60 described later, but is not limited thereto. The ground pattern 20 may be larger than the annular pattern 60. The ground pattern 20 is formed with a through hole 21 for maintaining non-contact with a power supply unit 50 described later.

  The power feeding pattern 30 is an elliptical plate-like member (including a foil) made of a conductor such as copper. The power supply pattern 30 is disposed to face the ground pattern 20 with a predetermined interval through the support substrate 10 so that the surfaces of the power supply pattern 30 are parallel (including substantially parallel). The length (major axis) in the major axis direction and the length (minor axis) in the minor axis direction of the power supply pattern 30 may be appropriately designed. As another aspect, the shape of the power supply pattern 30 may be a perfect circle or a rectangle, or may be another shape (for example, a triangle). Moreover, a partial notch, a slot, or the like may be provided. The power supply pattern 30 and the ground pattern 20 face each other, thereby forming a capacitance according to the area of the power supply pattern 30.

  The short-circuit portion 40 is electrically connected to the power supply pattern 30 and the ground pattern 20. The short circuit part 40 should just be implement | achieved by the electroconductive pin (it is set as a short pin), for example. The short-circuit portion 40 is provided at the center portion of the power feeding pattern 30.

  The central portion here is the intersection (ie, the center) of the major axis and the minor axis of the power supply pattern 30 and its vicinity, and is caused by the deviation between the center of the power supply pattern 30 and the short-circuit portion 40. Refers to a region where the bias of directivity with respect to is within a predetermined allowable range. The central portion of the power feeding pattern 30 may be a region within a certain distance from the center of the power feeding pattern 30, for example. The constant distance here may be, for example, a length of about one fifth of the length of the short axis (or long axis) of the power feeding pattern 30. The short-circuit unit 40 has a predetermined inductance.

  The power feeding unit 50 electrically connects the inner conductor of the coaxial cable and the power feeding pattern 30. The power supply unit 50 may be realized by a conductive pin (referred to as a power supply pin) that passes through the support substrate 10 through the through hole 21. The electrical connection between the ground pattern 20 and the power supply pin (that is, the power supply unit 50) is maintained by the through hole 21.

  The connection point 32 between the power supply unit 50 and the power supply pattern 30 may be provided at a position where impedance matching between the coaxial cable and the antenna device 100 can be achieved at the target frequency F. In the present embodiment, the connection point 32 is provided in the vicinity of the short-circuit portion 40, that is, in the center portion of the power feeding pattern 30. The state where the impedance is matched is not limited to the complete matching state, but includes a state where the loss due to the impedance mismatch is within a predetermined allowable range. The power feeding unit 50 has a predetermined inductance and resistance value.

  The annular pattern 60 is a ring-shaped member made of a conductor and having a predetermined width, and is formed in an annular shape having a predetermined width so as to have a certain distance from the edge 31 of the power feeding pattern 30 on the upper surface. ing. The inner periphery 61 of the annular pattern 60 and the edge 31 of the power feeding pattern 30 are parallel (including substantially parallel). The distance between the inner periphery of the annular pattern 60 and the power feeding pattern 30 and the width of the annular pattern 60 may be appropriately designed so as to form desired capacitance and inductance described later. This annular pattern 60 corresponds to the first annular pattern recited in the claims.

  Note that the separation between the edge portion 31 of the power feeding pattern 30 and the inner peripheral portion 61 of the annular pattern 60 does not have to be strictly constant in the entire region. The separation between the edge portion 31 of the power feeding pattern 30 and the inner peripheral portion 61 of the annular pattern 60 may vary within a range in which the deviation in directivity in the horizontal direction, which will be described later, falls within a predetermined allowable range.

  The connection part 70 is a member made of a conductor, and electrically connects the power feeding pattern 30 and the annular pattern 60. The length of the connecting portion 70 corresponds to the separation between the inner peripheral portion 61 of the annular pattern 60 and the edge portion 31 of the power feeding pattern 30. The connection part 70 is provided with the inductance according to the length. Here, the connection portion 70 is realized by pattern formation on the upper surface of the support substrate 10. However, as another embodiment, the connection portion 70 may be realized by a conductive element such as a jumper wire. good.

  By the way, although the electric power feeding pattern 30, the annular pattern 60, and the connecting portion 70 provided on the upper surface are described with different names here for convenience, they may be integrated members. For example, the power feeding pattern 30, the annular pattern 60, and the connecting portion 70 may be realized by being cut out from one copper plate. Further, the power feeding pattern 30, the annular pattern 60, and the connection portion 70 may be formed by an additive method or a subtractive method. Hereinafter, the power feeding pattern 30, the annular pattern 60, and the connection part 70 are collectively referred to as an element part.

  Further, the annular pattern 60 is mounted so as to maintain a certain distance from the power feeding pattern 30 and to have a certain width. For this reason, the shape of the inner peripheral portion 61 and the shape of the outer peripheral portion 62 of the annular pattern 60 are substantially similar to the power supply pattern 30, and the center of any figure coincides with the center of the power supply pattern 30. Therefore, the central portion of the power feeding pattern 30 corresponds to the central portion of the element portion. The outer peripheral portion 62 of the annular pattern 60 corresponds to the outer edge portion of the element portion.

  FIG. 3 shows an equivalent circuit of the antenna device 100. The inductor L0 and the resistor R0 are elements corresponding to the power supply unit 50, and have an inductance and a resistance value corresponding to the shape and material of the power supply unit 50, respectively. The inductor Lp is an element corresponding to the short-circuit portion 40 and includes an inductance corresponding to the length of the short-circuit portion 40. The capacitor Cp is an element corresponding to the power feeding pattern 30 and has a capacitance corresponding to the area of the power feeding pattern 30.

  The inductor Ld is an element derived from the connection portion 70, and its inductance is determined by the length of the connection portion 70. The capacitor Ca and the inductor La are elements derived from the annular pattern 60, and the size of each is determined by the width of the annular pattern 60, the separation from the inner peripheral portion 61 with respect to the edge 31 of the power feeding pattern 30, and the like.

  In the equivalent circuit, the inductor Ld, the inductor La, and the capacitor Ca are connected in series, and partially form a series circuit (referred to as a series circuit unit) 1 so as to be surrounded by a one-dot chain line in FIG.

  FIG. 4 is a graph qualitatively showing the relationship between the impedance Z and the frequency of the series circuit unit 1. The series circuit unit 1 acts as a capacitive reactance at a frequency lower than the resonance frequency Fa, and acts as an inductive reactance at a frequency higher than the resonance frequency Fa. The resonance frequency Fa of the series circuit unit 1 is determined by the inductance provided in the inductors Ld and La and the capacitance provided in the capacitor Ca.

  Therefore, when the inductors Ld and La and the capacitor Ca are designed so that the resonance frequency Fa is higher than the target frequency F, the series circuit unit 1 acts as a capacitive reactance at the target frequency F. Designing the inductors Ld and La and the capacitor Ca corresponds to designing the shape and positional relationship of the connection portion 70 corresponding to the inductor Ld and the annular pattern 60 corresponding to the inductor La and capacitor Ca. .

  FIG. 5 is a graph showing the relationship between the value of the equivalent capacitance value (assumed to be an equivalent capacitance value) of the series circuit unit 1 acting as capacitive reactance and the frequency when the resonance frequency Fa is 790 MHz. . As illustrated in FIG. 5, the equivalent capacitance value of the series circuit unit 1 increases as the frequency is closer to the resonance frequency Fa.

  In the present embodiment, in consideration of the above consideration, the inductors Ld and La and the capacitor Ca are designed so that the resonance frequency Fa is 790 MHz as an example. The resonance frequency Fa is not limited to 790 MHz, and may be a frequency higher than the target frequency F.

  By setting the resonance frequency Fa to a frequency higher than the target frequency F, the series circuit unit 1 acts as a capacitive reactance as described above. Since the series circuit unit 1 acts as a capacitive reactance, the series circuit unit 1 in the equivalent circuit is regarded as a capacitor having a predetermined capacitance (referred to as a capacitor C1 for convenience) as shown in FIG. Can do.

  Since the capacitor C1 is connected in parallel with the capacitor Cp, they can be regarded as one capacitor Cp1 as shown in FIG. The capacitance of the capacitor Cp1 is the sum of the capacitance of the capacitor C1 and the capacitance of the capacitor Cp. Since the capacitor Cp1 and the inductor Lp are connected in parallel, parallel resonance occurs at a frequency (referred to as a parallel resonance frequency) determined from the capacitance of the capacitor Cp1 and the inductance of the inductor Lp. That is, the antenna device 100 resonates in parallel at the parallel resonance frequency.

  Therefore, the antenna device 100 can be caused to resonate in parallel at the target frequency F by adjusting the capacitance of the capacitor Cp1 and the inductance of the inductor Lp so that the parallel resonance frequency matches the target frequency F. For example, when the inductance included in the inductor Lp corresponding to the short circuit portion 40 is treated as a constant value, first, the target capacitance necessary for parallel resonance is calculated from the inductance included in the inductor Lp and the target frequency F. .

  Then, if the capacitance of each of the capacitor Cp and the capacitor C1 is determined so that the capacitance of the capacitor Cp1 matches the target capacitance, and the shape and arrangement of the members corresponding to each capacitor are determined. Good. That is, the shape and arrangement of each element such as the feeding pattern 30, the annular pattern 60, and the connection part 70 included in the element unit may be adjusted as appropriate so that the antenna device 100 performs parallel resonance at a predetermined target frequency F.

  Note that the inductance of the short-circuit portion 40 may be handled as an adjustable parameter instead of a fixed value. However, since the inductance of the short-circuit portion 40 is determined by the length of the short-circuit portion 40, that is, the separation between the element layer and the ground pattern, it is difficult to change the design.

[Operation of Antenna Device 100]
Next, the operation when the antenna device 100 is in parallel resonance will be described. When the antenna device 100 resonates in parallel, an electric field perpendicular to the ground pattern 20 (and the element portion) is generated between the ground pattern 20 and the element portion. The vertical electric field propagates from the short-circuit portion 40 toward the outer edge portion of the element portion. At the outer edge portion of the element portion, the vertical electric field becomes a vertically polarized electric field and propagates through the space. And the antenna apparatus 100 radiates | emits a vertically polarized wave in a centrifugal direction in the outer edge part of an element part.

  More specifically, a current generated in the element portion by parallel resonance flows in a direction from the outer edge portion of the element portion toward the central portion of the element portion where the short-circuit portion 40 is provided (that is, the central portion of the power feeding pattern 30). That is, the current is concentrated at the center of the element part, and the amplitude of the current standing wave is maximum at the center of the element part and zero at both ends.

  In addition, since the short-circuit portion 40 is provided at the center portion of the element portion, the voltage standing wave has a maximum amplitude at the outer edge portion of the element portion and an amplitude of 0 near the center portion. The same sign is also used in the vertical direction in the region.

  Since the vertical electric field generated between the element portion and the ground pattern 20 is proportional to the voltage distribution, the traveling direction thereof is the same in any region as viewed from the short-circuit portion 40 (for example, from the short-circuit portion 40 to the element portion). Direction toward the edge). In addition, the strength is 0 near the center and maximum at the outer edge of the element portion. That is, the electric field intensity increases from the short-circuit portion 40 toward the outer edge portion of the element portion, and is emitted as vertically polarized waves at the outer edge portion.

  For this reason, the antenna device 100 has the same gain in all directions from the center portion (that is, the short-circuit portion 40) of the element portion toward the outer edge portion at the target frequency F. In particular, when the antenna device 100 is placed so that the ground pattern 20 is horizontal, the antenna device 100 operates as an omnidirectional antenna in the horizontal direction.

  FIG. 8 shows the directivity of the antenna device 100 in a plane perpendicular to the antenna device 100 when the antenna device 100 is placed so that the ground pattern 20 is horizontal. FIG. 9 shows an antenna in a plane parallel to the antenna device 100 and including the antenna device 100 (for example, a plane including an element layer) when the antenna device 100 is installed so that the ground pattern 20 is horizontal. The directivity of the apparatus 100 is represented. Also from FIG. 9, it can be seen that the antenna apparatus 100 has a substantially non-directional horizontal plane directivity. FIG. 9 also shows that the gain of the antenna device 100 in the horizontal direction is 3.2 dBi.

[Effect of this embodiment]
Next, the antenna device 100X as a comparative configuration is introduced, and the effect of this embodiment on the miniaturization of the antenna device will be described.

  An antenna device 100X as a comparative configuration is a simplified version of the antenna device disclosed in Patent Document 1 for comparison with the configuration of the present embodiment. FIG. 10 is a diagram illustrating a configuration of an antenna device 100X as a comparative configuration, and corresponds to FIG. The antenna device 100 </ b> X includes a support substrate 10 </ b> X, a ground pattern 20 </ b> X, a power feeding pattern 30 </ b> X, a short circuit unit 40, and a power feeding unit 50. FIG. 11 is an equivalent circuit diagram of the antenna device 100X. The capacitor CpX is an element corresponding to the power feeding pattern 30X, and has a capacitance determined according to the area of the power feeding pattern 30X.

  In this comparative configuration, parallel resonance is caused by the capacitance formed between the ground pattern 20X and the power feeding pattern 30X and the inductance provided in the short-circuit portion 40. That is, in this comparative configuration, the capacitance formed between the power supply pattern 30X and the ground pattern 20X is an electrostatic capacitance that resonates in parallel at the target frequency F with the inductance of the short-circuit portion 40 (that is, the target capacitance). The area must match.

  On the other hand, according to the configuration of the present embodiment, the target capacitance is achieved by the sum of the capacitance of the capacitor Cp formed by the power feeding pattern 30 and the equivalent capacitance value of the series circuit unit 1. Therefore, the capacitance of the capacitor Cp1 formed by the power supply pattern 30 does not need to match the target capacitance, and the power supply pattern 30 can be made smaller than the power supply pattern 30X of the conventional configuration.

  Further, the equivalent capacitance value of the series circuit unit 1 varies depending on the magnitude of the difference between the target frequency F and the resonance frequency Fa. By adjusting the resonance frequency Fa, the amount of reduction in the area of the power feeding pattern 30 with respect to the power feeding pattern 30X can be made sufficiently larger than the area required for providing the annular pattern 60 around the power feeding pattern 30. .

  Therefore, according to the above configuration, when a certain predetermined frequency is set as the target frequency F, the antenna device can be downsized as compared with the comparative configuration. In other words, a lower frequency can be set as the target frequency F in the same antenna size. For example, when the target frequency F is 760 MHz, according to the configuration of the present embodiment, it can be realized with a size of about one third of the comparative configuration. In order to make the reduction amount of the area of the power feeding pattern 30 sufficiently larger than the area required for providing the annular pattern 60, the resonance frequency Fa is set to several percent of the target frequency F from the target frequency F. The frequency is preferably about 10% higher.

  By the way, as a comparative configuration (second comparative configuration) different from the above-described comparative configuration (for convenience, the first comparative configuration), a configuration in which the connection unit 70 is removed from the antenna device 100 of the present embodiment is also conceivable. .

  In such a second comparison configuration, the inductance derived from the connection unit 70 cannot be used as an element for determining the equivalent capacitance value of the series circuit unit 1. This means that the inductance component included in the series circuit unit is reduced as compared with the present embodiment, and the resonance frequency of the series circuit unit is reduced.

  When the resonance frequency of the series circuit unit in the second comparison configuration is made equal to the resonance frequency Fa in the present embodiment, it is necessary to increase the capacitance of the capacitor Ca derived from the annular pattern 60 or the inductance of the inductor La. There is. Even when the capacitance of the capacitor Ca is increased or when the inductance of the inductor La is increased, the antenna size is increased because the area of the annular pattern 60 needs to be increased in any case.

  That is, in order to transmit / receive a radio wave having the same target frequency F as in the present embodiment by the second comparison configuration, the antenna size increases. In other words, according to the configuration of the present embodiment, the size can be reduced as compared with the second comparison configuration.

<Modification 1-1>
In the above, an example in which the planar shape of the power feeding pattern 30 is an elliptical shape and the planar shape of the entire antenna device 100 is also an elliptical shape along with the elliptical shape is illustrated. An example of a schematic configuration of an antenna device 100A as the first modification is shown in FIG. The antenna device 100A includes a rectangular power feeding pattern 30A. Since the annular pattern 60A is formed on the upper surface so as to maintain a certain distance from the power feeding pattern 30A and to have a certain width, the outer peripheral shape of the annular pattern 60A is also rectangular.

  Here, in order to reduce horizontal plane directivity distortion, a rectangular corner is chamfered with a predetermined curvature. Thus, the shape which chamfered the corner | angular part shall also be contained in a rectangular shape. Of course, as another aspect, chamfering may not be performed, and the corner may be a right angle.

<Second Embodiment>
Next, a second embodiment of the present invention will be described with reference to the drawings. In the following, members having the same functions as those of the configuration of the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted.

  FIG. 13 is a top view of the antenna device 200 according to the second embodiment, and corresponds to FIG. 1 illustrating the top view of the antenna device 100 according to the first embodiment described above. FIG. 14 is a cross-sectional view of the antenna device 200 taken along line XIV-XIV shown in FIG.

  The antenna device 200 according to the second embodiment includes a support substrate 10, a ground pattern 20, a power feeding pattern 30, a short-circuit portion 40, a power feeding portion 50, a first annular pattern 60, a connection portion 70, and a second annular pattern 80. . The first annular pattern 60 is a member corresponding to the annular pattern in the first embodiment described above.

  The second annular pattern 80 is a member made of a conductor. The second annular pattern 80 is a ring on the upper surface of the support substrate 10 outside the first annular pattern 60 so as to have a certain distance from the outer periphery of the first annular pattern 60. It is formed into a shape. The second annular pattern 80 has a predetermined width. The outside of the first annular pattern 60 refers to a region on the upper surface of the support substrate 10 on the side where the power supply pattern 30 is not disposed with respect to the first annular pattern 60.

  The second annular pattern 80 forms a predetermined capacitance by capacitively coupling with the first annular pattern 60. The distance between the inner peripheral portion 81 of the second annular pattern 80 and the outer peripheral portion 62 of the first annular pattern 60 and the width of the second annular pattern 80 form a desired capacitance and inductance described later. In addition, it may be designed as appropriate.

  The separation between the inner peripheral portion 81 of the second annular pattern 80 and the outer peripheral portion 62 of the first annular pattern 60 is a value sufficiently smaller than the width of the first annular pattern 60 and the width of the second annular pattern 80. It is preferable. For example, the separation between the inner peripheral portion 81 of the second annular pattern 80 and the outer peripheral portion 62 of the first annular pattern 60 is not more than one-tenth of the width of the first annular pattern 60 and the second annular pattern It is preferable that it is 1/10 or less of the width of 80.

  The support substrate 10 in the antenna device 200 plays a role of supporting the feeding pattern 30, the annular pattern 60, the connection portion 70, and the second annular pattern 80 so as to face the ground pattern 20 at a predetermined interval. . The element part in 2nd Embodiment shall point out the electric power feeding pattern 30, the cyclic | annular pattern 60, the connection part 70, and the 2nd cyclic | annular pattern 80. FIG. Further, the ground pattern 20 in the second embodiment may be the same size as the element portion or larger. The ground pattern 20 only needs to have a sufficient size to face the entire area of the element portion.

  FIG. 15 shows an equivalent circuit of the antenna device 200. The inductor L0, the resistor R0, the inductor Lp, the capacitor Cp, the inductor La, the inductor Ld, and the capacitor Ca are as described above.

  The capacitor Cg is an element derived from capacitive coupling between the first annular pattern 60 and the second annular pattern 80, and the capacitance is determined by the separation between the first annular pattern 60 and the second annular pattern 80. The capacitor Cb and the inductor La are elements derived from the second annular pattern 80, and the capacitance and inductance thereof are determined by the shape (width, etc.) of the second annular pattern 80.

  By designing each part such that the capacitance of the capacitor Cg is sufficiently smaller than the capacitance of the capacitor Ca, the capacitor Cg is added in parallel to the capacitor Ca in the equivalent circuit.

  As shown in FIG. 15, the inductor Ld, the inductor La, and the capacitor Ca form a series circuit (for convenience, the first series circuit unit) 1 as in the first embodiment (one point in FIG. 15). The part enclosed with a chain line). In the present embodiment, as an example, the inductor La and the capacitor Ca are designed so that the first resonance frequency Fa as the resonance frequency of the first series circuit unit 1 is 1210 MHz. That is, the shape (width) of the first annular pattern 60 and the separation from the power feeding pattern 30 are determined so that the first resonance frequency Fa is 1210 MHz. The first resonance frequency Fa only needs to be higher than the target frequency F, and may be a value other than 1210 MHz. FIG. 16 is a graph showing an equivalent capacitance value of the first series circuit unit 1 at a frequency lower than the first resonance frequency Fa.

  Further, the inductor Lb derived from the second annular pattern 80 and the capacitor Cb are also connected in series to construct a series circuit (referred to as a second series circuit unit for convenience) 2. The second series circuit unit 2 performs series resonance at a resonance frequency (referred to as a second resonance frequency) Fb determined from the inductance of the inductor Lb and the capacitance of the capacitor Cb. Similar to the first series circuit unit 1, the second series circuit unit 2 also acts as a capacitive reactance at a frequency lower than the second resonance frequency Fb.

  FIG. 17 shows the relationship between the equivalent electrostatic capacitance value (assumed equivalent capacitance value) and frequency of the second series circuit section 2 acting as capacitive reactance when the second resonance frequency Fb is 1310 MHz. It is a graph. As shown in FIG. 17, the equivalent capacitance value increases as the frequency approaches the second resonance frequency Fb.

  In the present embodiment, as an example, the inductor Lb and the capacitor Cb are designed so that the second resonance frequency Fb is 1310 MHz. That is, the shape (width, etc.) of the second annular pattern 80 is determined so that the second resonance frequency Fb is 1310 MHz.

  Note that the second resonance frequency Fb is not limited to 1310 MHz, and may be any frequency that is higher than the first resonance frequency Fa. When the first series circuit unit 1 acts as a capacitive reactance by setting the second resonance frequency Fb to be higher than the first resonance frequency Fa as described above, the second series circuit unit 2 also has a capacitance. Acts as a sex reactance. That is, at the target frequency F, both the first series circuit unit 1 and the second series circuit unit 2 behave as capacitive reactance.

  Further, since the second series circuit unit 2 acts as a capacitive reactance at the target frequency F, the second series circuit unit 2 in the equivalent circuit of FIG. 15 is a capacitor having a predetermined capacitance as shown in FIG. (Denoted as capacitor C2 for convenience). The capacitance of the capacitor C2 is an equivalent capacitance value at the target frequency F of the second series circuit unit 2.

  In FIG. 18, since the capacitor Cg and the capacitor C2 are connected in series, the circuit portion composed of the capacitor Cg and the capacitor C2 can be combined and handled as one capacitor C2g. Note that the capacitance of the capacitor C2g is obtained by a known calculation method.

  Further, since the capacitor C2g obtained by combining the capacitor Cg and the capacitor C2 and the capacitor Ca are connected in parallel, they can be regarded as one capacitor Ca2 as shown in FIG. The capacitance included in the capacitor Ca2 is the sum of the capacitance included in the capacitor Ca and the capacitance of the capacitor C2g.

  Since the inductors La and Ld and the capacitor C2g are connected in series, a series circuit (referred to as a third series circuit unit) 3 is partially constructed so as to be surrounded by a broken line in FIG. That is, the inductors La, Ld, Lb and the capacitors Ca, Cb, Cg generated by adding the first annular pattern 60, the connecting portion 70, and the second annular pattern 80 to the power feeding pattern 30 are the third series circuit portion 3. Function as.

  The third series circuit unit 3 is designed so that the first resonance frequency Fa is 1210 MHz and the second resonance frequency Fb is 1310 MHz, and thus acts as a capacitive reactance near the target frequency F. Specifically, the resonance frequency (referred to as the third resonance frequency) Fc of the third series circuit unit 3 is about 790 MHz. FIG. 20 is a graph showing the equivalent capacitance value of the third series circuit unit 3 at a frequency lower than the third resonance frequency Fc.

  As illustrated in FIG. 20, the third series circuit unit 3 behaves as a capacitor C3 having a capacitance of several tens of pF at the target frequency F. Therefore, the equivalent circuit shown in FIG. 19 can be further transformed into the equivalent circuit shown in FIG. Further, since the capacitor Cp and the capacitor C3 are connected in parallel, the capacitor Cp3 can be regarded as a capacitor Cp3 having a combined capacitance of the capacitor Cp and the capacitor C3. The capacitance of the capacitor Cp3 is the sum of the capacitance of the capacitor Cp and the capacitance of the capacitor C3.

  That is, the equivalent circuit of the antenna device 200 shown in FIG. 15 is finally a circuit in which the inductor Lp and the capacitor Cp3 are connected in parallel at the target frequency F as shown in FIG.

  Then, when the inductor Lp and the capacitor Cp3 resonate in parallel, the antenna device 200 operates as an antenna having horizontal plane omnidirectionality, as in the first embodiment. 23 and 24 are diagrams showing simulation results of the operation of the present embodiment. FIG. 23 shows the magnetic field distribution in the element layer, and FIG. 24 shows the electric field distribution in the cross section corresponding to FIG.

  FIG. 23 shows that a magnetic current is generated in the center of the element portion in parallel with the element layer. The electric field is generated in a direction orthogonal to the magnetic current. Therefore, it can be seen from FIG. 23 that a vertical electric field is generated between the element portion and the ground pattern 20.

[Effects of Second Embodiment]
According to the configuration of the present embodiment, the same effects as those of the first embodiment can be obtained. That is, when a certain predetermined frequency is the target frequency F, the antenna device can be downsized as compared with the first comparison configuration described in the description of the first embodiment. In other words, a lower frequency can be set as the target frequency F in the same antenna size.

  In addition, according to the configuration of the present embodiment, two series circuits act as capacitive reactances, and an equivalent capacitance value (capacitance of the capacitor C3) determined as a result is added to the capacitance derived from the power feeding pattern 30. Achieve the target capacitance. Therefore, when the antenna size is the same, the capacitance added to the capacitance derived from the power feeding pattern 30 can be increased as compared with the first embodiment. In other words, when the same frequency is set as the target frequency F, according to the configuration of the second embodiment, the size can be reduced as compared with the first embodiment.

  For example, when the target frequency F is 760 MHz, according to the configuration of the present embodiment, the size can be further reduced by about 30% from the antenna device 100 of the first embodiment. Further, it can be realized with a size of about a quarter of the first comparison configuration described in the effect of the first embodiment.

  Further, according to the configuration of the second embodiment, by providing the second annular pattern 80 outside the first annular pattern 60, the capacitive component at the outer edge of the antenna device 200 is changed to the antenna device 100 according to the first embodiment. Can be increased. As shown in FIG. 24, the vertical electric field is generated mainly in the vicinity of the outer edge portion of the antenna device 200 during parallel resonance. The factor that induces the electric field is a capacitive structure in the vicinity of the outer edge of the antenna device 200.

  Therefore, according to the antenna device 200 of the present embodiment in which the electrostatic capacitance in the vicinity of the outer edge portion of the antenna device 200 is increased, the gain can be increased as compared with the antenna device 100 of the first embodiment. According to the simulation, the gain can be improved by about 0.8 dB in the present embodiment than in the first embodiment.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to the above-mentioned embodiment, The following modification is also contained in the technical scope of this invention, Furthermore, the summary other than the following is also included. Various modifications can be made without departing from the scope.

<Modification 2-1>
In the first and second embodiments, an example in which the support substrate 10 is a plate-like member having a uniform resin filling density is illustrated, but the present invention is not limited thereto. For example, the support substrate 10 of the antenna device 200 of the second embodiment is formed in an annular shape so as to support the first annular pattern 60 and the second annular pattern 80, and as shown in FIG. It is good also as a structure which can be equipped with.

  As shown in FIG. 26, the antenna device 200 may include two opposing support substrates 11 and 12, an element portion may be formed on the support substrate 11, and a ground pattern 20 may be formed on the support substrate 12. . The support substrate 11 and the support substrate 12 may be supported so as to face each other by the short-circuit portion 40 or a member (not shown).

<Modification 2-2>
In the second embodiment, the planar shape of the power feeding pattern 30 is an ellipse, and the planar shape of the entire antenna device 200 is accordingly substantially similar to the elliptical shape. However, the present invention is not limited to this. As described in Modification 1-1, the antenna device 200 may have the power feeding pattern 30 as a rectangle, and accordingly, the planar shape of the entire antenna device 200 may be a substantially similar rectangle.

  Of course, the planar shape of the entire antenna device 200 is not limited to an ellipse or a rectangle, but may be a triangle, a perfect circle, or another polygon.

<Modification 2-3>
As shown in FIG. 27, the first annular pattern 60 may be provided with a gap at one place or a plurality of places. FIG. 27 illustrates an example in which three gaps G1, G2, and G3 are provided.

<Modification 2-4>
Moreover, a resistance element, an inductor, and a capacitor may be inserted into the gap provided in the first annular pattern 60 in Modification 2-3. FIG. 28 illustrates a mode in which a resistance element is inserted in the gap.

<Modification 2-5>
The connection portion 70 may also be partially provided with a gap, and ends that form the gap may be connected by an inductor or a capacitor. FIG. 29 illustrates an aspect in which an inductor is inserted into a gap provided in the connection portion 70. Note that the modified example 2-3, modified example 2-4, and modified example 2-5 can also be applied to the first embodiment.

<Modification 2-6>
Similarly to the first annular pattern 60 described in Modification 2-3, the second annular pattern 80 may be provided with a gap at one place or a plurality of places.

<Modification 2-7>
Moreover, a resistance element, an inductor, or a capacitor may be inserted into the gap provided in the second annular pattern 80 in Modification 2-6.

<Modification 2-8>
The first annular pattern 60 and the second annular pattern 80 may be connected by one or a plurality of resistance elements, inductors, or capacitors. FIG. 30 illustrates a mode in which the first annular pattern 60 and the second annular pattern 80 are connected by three inductors 91. The first annular pattern 60 and the second annular pattern 80 may be connected by a plurality of types of elements.

<Modification 2-9>
The 1st annular pattern 60 and the 2nd annular pattern 80 may be electrically connected by the conductor line 92 which has electroconductivity in one place or multiple places. FIG. 31 illustrates a mode in which the first annular pattern 60 and the second annular pattern 80 are connected at three locations. According to the configuration of Modified Example 2-9, the capacitance generated between the first annular pattern 60 and the second annular pattern 80 can be adjusted by the width W3 of the conductor line 92 and the number thereof. Further, by adding the conductor line 92, an effect of suppressing static electricity from being charged in the second annular pattern 80 can be obtained.

  When the first annular pattern 60, the second annular pattern 80 and the conductor line 92 are connected, an inductor having an inductance determined according to the width of the conductor line 92 is connected in parallel to the capacitor Cg in the equivalent circuit of the antenna device 200. Will be.

  Here, when the width W3 of the conductor line 92 is relatively larger than the width W1 of the first annular pattern 60 and the width W2 of the second annular pattern 80, the inductance derived from the conductor line 92 is reduced. As a result, in the equivalent circuit, the separation between the first annular pattern 60 and the second annular pattern 80 does not function as the capacitor Cg. That is, it will not operate as the second embodiment described above.

  Therefore, the width W3 of the conductor line 92 needs to be smaller than the width W1 of the first annular pattern 60 and the width W2 of the second annular pattern 80, and the inductance connected in parallel to the capacitor Cg needs to be a large value. The conductor line 92 corresponds to the bridging portion described in the claims. The width W1 of the first annular pattern 60 corresponds to the first width described in the claims, and the width W2 of the second annular pattern 80 corresponds to the second width described in the claims.

<Modification 2-10>
The first annular pattern 60 and the second annular pattern 80 may be formed such that the gap between the first annular pattern 60 and the second annular pattern 80 has a sinusoidal waveform or a meander shape that maintains a constant width.

<Modification 2-11>
The positional relationship between the first annular pattern 60 and the second annular pattern 80 may be interchanged. That is, the second annular pattern 80 may be provided inside the first annular pattern 60. FIG. 32 shows a configuration of an antenna device 200A as an example of such a mode.

  The second annular pattern 80 in the antenna device 200 </ b> A is formed inside the first annular pattern 60 such that the outer periphery thereof has a certain distance from the inner periphery of the first annular pattern 60. In addition, the second annular pattern 80 is provided with a gap in the vicinity of the connection portion 70 in order to keep electrical disconnection from the connection portion 70.

<Modification 2-12>
The configuration in which the second annular pattern 80 is provided inside the first annular pattern 60 is not limited to the configuration illustrated in FIG. The configuration of the antenna device 200B as another configuration including the second annular pattern 80 inside the first annular pattern 60 is shown in FIGS. 33 and 34. FIG.

  FIG. 33 is a top view of the antenna device 200B, and FIG. 34 is a cross-sectional view of the antenna device 200B along the alternate long and short dash line shown in FIG. As illustrated in Modification 2-1, the antenna device 200B includes two support substrates 11 and 12 that face each other. Then, the power feeding pattern 30, the first annular pattern 60, and the connection portion 70 are formed on one surface (first surface) of the support substrate 11, and the other surface (first surface) of the support substrate 11 is formed. A second annular pattern 80 is formed.

  At this time, the second annular pattern 80 is provided on the first lower surface so as to maintain the same spacing as described above in the plane direction with respect to the first annular pattern 60. Here, the separation between the second annular pattern 80 and the first annular pattern 60 in the planar direction represents the shortest distance between the second annular pattern 80 and the first annular pattern 60 when the antenna device 200 is viewed from above. Strictly speaking, it means a separation when the second annular pattern 80 and the first annular pattern 60 are orthogonally projected onto a plane parallel to the first upper surface (and the first lower surface).

  According to such a configuration, without providing a gap in the second annular pattern 80, the electrical connection between the connecting portion 70 and the second annular pattern 80 is maintained, and the first annular pattern 60 is placed inside the first annular pattern 60. A bi-annular pattern 80 can be provided. The ground pattern 20 may be disposed on either surface of the support substrate 12. In FIG. 34, the aspect which provided the ground pattern 20 in the surface (it is set as the 2nd lower surface) which is not opposite to the support substrate 11 among the surfaces with which the support substrate 12 is provided is illustrated. Of course, the ground pattern 20 may be provided on the surface of the support substrate 12 that faces the support substrate 11 (referred to as the second upper surface).

<Modification 2-13>
Moreover, the structure of 200 C of antenna apparatuses as another structure provided with the 2nd annular pattern 80 inside the 1st annular pattern 60 is shown in FIG.35 and FIG.36. FIG. 35 is a top view of the antenna device 200C, and FIG. 36 is an enlarged view of the vicinity of the connection portion 70 in the cross section of the antenna device 200C taken along the alternate long and short dash line shown in FIG.

  The antenna device 200 </ b> B includes two support substrates 11 and 12 that face each other, similarly to the modification 2-12. The power supply pattern 30, the first annular pattern 60, and the second annular pattern 80 are provided on the first upper surface, and the ground pattern 20 is provided on the second lower surface.

  The connection part 70 in this modified example 2-13 penetrates the upper surface side connection part 71 formed on the first upper surface, the lower surface side connection part 72 formed on the first lower surface, and the support substrate 11, and is connected to the upper surface side. Through vias 73 and 74 that electrically connect the portion 71 and the lower surface side connection portion 72 are provided.

  The upper surface side connecting portion 71 is a line-shaped conductor having a predetermined width, and one end is electrically connected to the power feeding pattern 30 and the other end is extended until the distance from the second annular pattern 80 reaches a predetermined value. Established. The lower surface side connection portion 72 is, for example, a line-shaped conductor having a predetermined width. From the position corresponding to the lower portion of the upper surface side connection portion 71 on the second annular pattern 80 side on the first lower surface, It extends to a position corresponding to the lower part of the annular pattern 60. The upper surface side connection portion 71 and the lower surface side connection portion 72 function as the connection portion 70 by being electrically connected through the through vias 73 and 74. Even in such an aspect, the same effects as those of the second embodiment can be obtained.

100 · 100A · 200 · 200A to 200C Antenna device, 10 to 12 Support substrate, 20 Ground pattern, 30 Feeding pattern, 40 Short circuit part, 50 Feeding part, 60 Annular pattern (first annular pattern), 70 Connection part, 80 2-ring pattern, G1-G3 gap, 91 inductor, 92 conductor line (bridge)

Claims (11)

A ground pattern (20), which is a flat conductor disposed on the first plane;
A planar conductor disposed so as to face the ground pattern in a second plane parallel to the first plane, the feeding pattern (30) connected to a feeding line;
A short-circuit portion (40) for electrically connecting the power supply pattern and the ground pattern at a central portion of the power supply pattern;
A first annular pattern (60) realized using a conductor formed in a ring shape so as to have a predetermined distance from an edge of the power feeding pattern in the second plane;
An antenna device comprising: a connection portion (70) for electrically connecting the power feeding pattern and the first annular pattern. In claim 1,
The antenna apparatus, wherein the first annular pattern and the connection portion form a series circuit that resonates at a frequency higher than a predetermined target frequency that is a target of at least one of transmission and reception. In claim 1 or 2,
The antenna device according to claim 1, wherein the feeding pattern is elliptical. In claim 1,
A conductive second annular pattern (80) formed in an annular shape in a plane parallel to the first plane so as to have a predetermined separation from the first annular pattern in a planar direction, Antenna device to do. In claim 4,
The antenna apparatus, wherein the first annular pattern and the connection portion form a series circuit that resonates at a frequency higher than a predetermined target frequency that is a target of at least one of transmission and reception. In claim 4 or 5,
The antenna device, wherein the second annular pattern resonates in series at a frequency higher than a predetermined target frequency that is a target of at least one of transmission and reception. In claim 6,
The antenna device, wherein the system including the first annular pattern, the connection portion, and the second annular pattern forms a series circuit that resonates at a frequency higher than the target frequency. In any one of Claims 4-7,
The antenna device, wherein the second annular pattern is provided on the second plane. In claim 8,
The antenna device, wherein the second annular pattern is provided outside the first annular pattern in the second plane. In any one of Claims 4-9,
The separation between the first annular pattern and the second annular pattern in the planar direction is smaller than the first width that is the width of the first annular pattern and more than the second width that is the width of the second annular pattern. An antenna device characterized by being small. In claim 10,
Comprising at least one bridging portion (92) connecting the first annular pattern and the second annular pattern;
The width of the bridging portion is sufficiently smaller than any of the first width and the second width.

Images