JP2015159597A - Patch antenna device and radio wave reception equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-gain patch antenna device and radio wave reception equipment, adjusted to obtain a circular polarization characteristic, with a simple structure.SOLUTION: A patch antenna device 100 includes a rectangular dielectric plate 114, a planar radiation electrode 113, a ground electrode 115 and a power supply member 116. The planar radiation electrode 113 includes, in a part corresponding to two short sides of the dielectric plate, a slit 117 which extends to a part corresponding to an opposite short side. In order to obtain the circular polarization characteristic, the power supply position of the power supply member 116 is offset from the center of the planar radiation electrode.

Description

The present invention relates to a patch antenna device and a radio wave receiving device including the patch antenna device.

2. Description of the Related Art Conventionally, there has been known a patch antenna device including a patch antenna in which a rectangular planar radiation electrode is disposed on an upper surface of a dielectric plate and transmits and receives a circularly polarized signal (for example, see Patent Document 1).
Such a patch antenna device is configured by adjusting the length of the side of the planar radiation electrode so that the axial ratio of the patch antenna matches the frequency of the circularly polarized signal.

JP 2002-198725 A

However, for example, in a small GPS (Global Positioning System) device mounted on a portable radio wave receiving device such as a camera or a wristwatch, the patch antenna device may have to be mounted in a narrow rectangular parallelepiped housing. is there. In this case, since the casing is wide, it is necessary to reduce the size of the dielectric plate itself according to the width of the casing.
In this case, if the dielectric plate and the planar radiating conductor are reduced in the same ratio according to the scaling rule, the volume of the patch antenna is reduced, and the antenna characteristics are deteriorated.
On the other hand, in order not to reduce the volume of the patch antenna, the width in the width direction of the dielectric plate and the planar radiation conductor is reduced to match the length in the width direction of the casing, while the dielectric plate and the planar radiation conductor When the length orthogonal to the width direction is increased, the antenna becomes a linearly polarized wave, so that there is a problem that the received power is halved compared to a circularly polarized wave antenna.

The present invention has been made in view of such a problem, and an object thereof is to provide a high-gain patch antenna device and a radio wave receiver that are adjusted to obtain circular polarization characteristics with a simple configuration. Yes.

The patch antenna device according to the present invention is
Patch antenna device comprising a rectangular dielectric plate, a planar radiation electrode disposed on one surface of the rectangular dielectric plate, a ground electrode disposed on the other surface of the rectangular dielectric plate, and a feeding member In
The planar radiation electrode is:
A slit having a first length extending toward a portion corresponding to the opposite side of the opposite side of the rectangular dielectric plate;
A second length slit having a shorter length than the first length slit;
With
By providing the slit having the first length and the slit having the second length, the difference between the two resonance frequencies is reduced.
Moreover, the radio wave receiving device according to the present invention is
A patch antenna device according to any one of claims 1 to 4 is provided in a device main body.

According to the present invention, the following effects can be obtained.
That is, in the planar radiation electrode, at least one slit extending toward a portion corresponding to the other opposite sides is formed in each of the portions corresponding to the two opposite sides of the rectangular dielectric plate. Therefore, even in the case of a rectangular dielectric plate, it is possible to reduce the deviation of the two resonance frequencies between the two opposite sides of the rectangular dielectric plate and the other two sides orthogonal thereto, Since the feed position of the feed member is impedance-adjusted with an offset from the center of the planar radiation electrode, a high gain patch antenna device adjusted to obtain a good circular polarization characteristic with a simple configuration, and A radio wave receiver can be realized.

1 is a perspective view of a patch antenna device according to a first embodiment of the present invention. It is a top view of the patch antenna apparatus of FIG. FIG. 2 is a cross-sectional view of a principal part showing a state where the patch antenna device of FIG. 1 is mounted on a circuit board. FIG. 3 is a partially cutaway plan view for explaining a feeding position of the patch antenna apparatus of FIG. 1. It is a graph which shows the radiation characteristic of the patch antenna apparatus of FIG. It is a perspective view of the patch antenna apparatus which concerns on 2nd Embodiment of this invention. It is a top view of the patch antenna apparatus of FIG. FIG. 6 is a cross-sectional view of a main part showing a state where the patch antenna device of FIG. 5 is mounted on a circuit board. FIG. 7 is a perspective view of a digital camera to which the patch antenna device of FIG. 6 is applied. It is a perspective view which expands and shows a part of digital camera of FIG. It is a top view which shows the 1st modification of a patch antenna apparatus. It is a top view which shows the 2nd modification of a patch antenna apparatus. It is a top view which shows the 3rd modification of a patch antenna apparatus.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

The patch antenna device 100 according to the embodiment has a structure as shown in FIGS. 1 to 3 and includes a patch antenna 110 and a conductive grounding member 120.

Of these, the patch antenna 110 includes a rectangular planar radiation electrode 113 and a rectangular dielectric plate 114.
A rectangular ground electrode 115 (see FIG. 3) and a power supply member 116 are provided.
Here, the dielectric plate 114 is a vertically long rectangle in plan view, and is made of, for example, ceramic.

A flat radiation electrode 113 is formed on the upper surface of the dielectric plate 114. The planar radiation electrode 113 is a vertically long rectangle in plan view, and is made of, for example, a silver foil, a metal plate, or a metal film having a predetermined thickness. The planar radiation electrode 113 is formed in a size that fits in the dielectric plate 114 in plan view. The long side of the planar radiation electrode 113 is parallel to the long side of the dielectric plate 114, and the short side of the planar radiation electrode 113 is parallel to the short side of the dielectric plate 114.
Each of the two short sides facing each other of the planar radiation electrode 113 is formed with one slit 117 extending toward the other short side. These two slits 117, 117
Are formed at positions facing each other across the center of the planar radiation electrode 113.

Further, as shown in FIG. 3, a ground electrode 115 is formed on the lower surface of the dielectric plate 114. The ground electrode 115 is formed on the entire back surface of the dielectric plate 114 except for a portion where the power supply member 116 is located and its periphery. That is, the outer shape of the ground electrode 115 is rectangular like the dielectric plate 114. The ground electrode 115 is made of, for example, a silver foil, a metal plate, or a metal film having a predetermined thickness.

On the other hand, as shown in FIG. 2, the conductive grounding member 120 is usually larger than the dielectric plate 114 in a plan view, and is fixed to the ground electrode 115 of the patch antenna 110 with a double-sided tape. The shape of the conductive ground member 120 is not particularly required to be a square, and it is desirable to increase the area as much as possible.
The power supply member 1 passes through the conductive grounding member 120 and the dielectric plate 114.
16 is provided. The upper end of the power supply member 116 is electrically connected to the flat radiation electrode 113 via solder.

Further, as shown in FIG. 3, a circuit board 130 is located below the conductive grounding member 120 corresponding to the GND of the circuit. The lower end portion of the power supply member 116 is connected to the circuit board 13.
It is electrically connected to a transmitting circuit and / or a receiving circuit (not shown) through a conductive pattern 130a formed on the lower surface of the circuit board 130.
In this embodiment, the longitudinal length (L1) of the rectangular planar radiation electrode 113 is 9
. 5 mm, the lateral length (L2) is 9.3 mm, the longitudinal length (L3) of the rectangular dielectric plate 114 is 12 mm, the lateral length (L4) is 11 mm, and the thickness (L5) is 4m
m, and the length (L6) of each slit 117 is 2.45 mm, but is not limited to these dimensions, and may be other dimensions.

Next, the feeding position of the patch antenna device 100, the length of the slit 117, and the length of the planar radiation electrode 113 will be described.
A position where the upper end of the power supply member 116 is electrically connected to the planar radiation electrode 113 is a power supply position. As shown in FIG. 4, here, the feeding position is on a straight line inclined by 45 ° with respect to an axis (Y axis) passing through the center O of the plane radiation electrode 113 and parallel to the short side of the plane radiation electrode 113. It is set to a position where the impedance is appropriate (50Ω).
The length (L6) of the slit 117 and the length (L1, L2) of the planar radiation electrode 113 are set to 2 of the patch antenna 110 on the assumption that the feeding position is maintained at the set position.
The phase difference is adjusted to 90 ° with respect to two resonance frequencies.
As a result, the patch antenna device 100 having good circular polarization characteristics can be realized.

FIG. 5 is a graph showing the result of a simulation of the radiation characteristics of the patch antenna device 100.
In the figure, the solid line indicates the antenna gain for right-handed circularly polarized waves, and the broken line indicates the antenna gain for left-handed circularly polarized waves (unit: dBic).
According to the figure, it can be seen that the right-handed polarization gain is large in the zenith direction of the antenna (0 ° position in FIG. 4), and conversely, the left-handed polarization gain is small in the zenith direction. And
About 16 dB as a cross polarization discriminating ability, which is the ability to discriminate between counterclockwise and clockwise in circular polarization
It can be seen that This means that sufficient performance is obtained as a circularly polarized antenna.

According to the patch antenna device 100 configured as described above, the following effects can be obtained.
That is, in the flat radiation electrode 113, the slit 1 extending toward each of the portions corresponding to the short sides facing each other of the rectangular dielectric plate 114 toward the other short sides facing each other.
17 is formed, the high frequency of the two resonance frequencies of the patch antenna 110 can be changed low. Further, the feeding position of the feeding member 116 to the planar radiation electrode 113 is set to an axis that passes through the center O of the planar radiation electrode 113 and is parallel to the short side of the planar radiation electrode 113 (Y
The position of the side of the plane radiation electrode 113 and the length of the slit 117 are changed because it is set at a position on a straight line inclined by 45 ° with respect to the axis) and at an appropriate impedance (50Ω). Thus, the phase difference can be adjusted to 90 ° with respect to the two resonance frequencies. Therefore, it is possible to realize a high-gain patch antenna device 100 that is adjusted to obtain circular polarization characteristics with a simple configuration.
In addition, since two slits 117 and 117 extending toward the center of the planar radiation electrode 113 are formed at positions on the short side opposite to the planar radiation electrode 113, the planar radiation is obtained as shown in FIG. Since the current flowing through the electrode 213 flows while detouring around the two slits 117 and 117 as indicated by broken lines, the length of the current path can be made longer. For this reason, the current path in the length direction of the short side of the planar radiation electrode 113 can be substantially lengthened, and the deviation between the higher resonance frequency and the lower resonance frequency can be effectively reduced.
Further, by forming the two slits 117, 117, the same result as that obtained when the length in the short side direction of the dielectric plate 114 is substantially increased can be obtained. Can be easily mounted.

[Second Embodiment]
FIG. 6 is a perspective view of the patch antenna device according to the second embodiment, FIG. 7 is a plan view of the patch antenna device, and FIG. 8 is a cross-sectional view of a principal part showing a state in which the patch antenna device is mounted on a circuit board. It is.
The patch antenna device 200 according to the second embodiment has a structure as shown in FIGS. 6 to 8 and includes a patch antenna 210 and a conductive grounding member 220.

Among these, the patch antenna 210 includes a planar radiation electrode 213, a dielectric plate 214, a ground electrode 215, and a power feeding member 216. The planar radiation electrode 213, the dielectric plate 214, the ground electrode 215, and the feeding member 216 in the patch antenna 210 are the planar radiation electrode 113, the dielectric plate 114, the ground electrode 115, and the feeding member in the patch antenna 110 of the first embodiment. 116.
Further, the setting of the power feeding position, the length of the slit 217, and the adjustment of the dimension of the planar radiation electrode 213 are performed by the same method as in the first embodiment.
The conductive grounding member 220 and the circuit board 230 are the same as the conductive grounding member 12 of the first embodiment.
0 and circuit board 130.
Therefore, detailed description of the common parts is omitted, and different parts are mainly described.

In the patch antenna device 200, both the planar radiation electrode 213 and the dielectric plate 214 are longer and narrower than those in the first embodiment.
That is, the length (L1) of the vertical side (long side) of the planar radiation electrode 213 is substantially the same as the length (L1) of the vertical side (long side) of the planar radiation electrode 113 of the first embodiment. Yes, flat radiation electrode 2
The length (L2) of the horizontal side (short side) of 13 is the horizontal side of the planar radiation electrode 113 of the first embodiment (
It is shorter than the length (L2) of the short side.
That is, in this embodiment, the rectangular planar radiation electrode 213 has a longitudinal length (L1) of 9.2 mm, a lateral length (L2) of 8.4 mm, and a rectangular dielectric plate 114. The vertical length (L3) is 13 mm, the horizontal length (L4) is 10 mm, and the thickness (L5) is
3 mm, and the lengths (L62, L61, L62) of the slits 217a to 217c are 3.
1 mm, 1.2 mm, and 3.1 mm. However, it is not limited to these dimensions, and other dimensions may be used.
In such a case, if one slit is formed on each of the two short sides of the planar radiation electrode 213 in the same manner as the patch antenna 110 of the first embodiment, the longitudinal length (L1) is the first length. In contrast to the first embodiment, the lateral length (L3
) Is significantly smaller than that of the first embodiment, so that the higher one of the two resonance frequencies of the patch antenna 210 is higher than that of the first embodiment, and is high. The difference between the resonance frequency of the lower side and the resonance frequency of the lower side becomes large, and it becomes difficult to match the frequency of the circularly polarized wave signal transmitted and received with the best point of the antenna axial ratio.
Therefore, in order to obtain the same antenna characteristics as in the first embodiment, 2 of the planar radiation electrode 213 is used.
Each of the three short side positions opens to the short side and extends toward the short side of the other side (opposite each other).
By forming the slits 217a, 217b, and 217c, the current path in the length direction of the short side is substantially increased, and the deviation between the higher resonance frequency and the lower resonance frequency is reduced. Yes.
Moreover, in the case of this embodiment, among the three slits 217a, 217b, 217c, the length (L61) of the central one slit 217b is set to the other two slits 217a on the left and right.
, 217c (L62). In this way, the current flowing through the planar radiation electrode 213 flows while detouring around the three slits 217a, 217b, and 217c having different lengths as indicated by the broken lines, so the three slits 217a , 2
Compared with the case where 17b and 217c are made the same length, the entire length of the current path can be made longer. For this reason, the current path in the length direction of the short side of the planar radiation electrode 213 can be substantially lengthened, and the deviation between the higher resonance frequency and the lower resonance frequency can be effectively reduced.

According to the patch antenna of the second embodiment, the following effects can be obtained.
That is, according to the patch antenna 210 of the patch antenna device 200 of the second embodiment, the patch antenna 110 of the first embodiment is mounted on the patch antenna 210 because the patch antenna 210 is longer than the patch antenna 110 of the first embodiment. Compared to the case, it can be mounted in a further elongated casing.

9 and 10 show the patch antenna device 200 of the second embodiment as a device main body 201.
An example of the radio wave receiving device mounted on is shown.
This radio wave receiving device is a digital camera 202. In this digital camera, the depth dimension of the housing 203 is reduced due to a demand for thinning.
Patch antenna device 20 mounted in the housing 203 of the digital camera 202
0 is attached to the top surface of the digital camera 202 so that the length direction of the short side of the dielectric plate 214 matches the depth direction of the digital camera 202. In this case, the patch antenna device 200 is mounted on the circuit board 230 exposed from the opening 201a of the device body 201.

FIG. 11 shows a first modification of the patch antenna.
In the patch antenna 410, a flat radiation electrode 413 is formed on the upper surface of a rectangular dielectric plate 414, a ground electrode (not shown) is formed on the lower surface of the dielectric plate 414, and the planar radiation electrode 413 is fed by a power supply member 416. Is being fed.
In this patch antenna 410, the slit 417 is composed of a linear portion 417a having a ridge width and a rectangular portion 417b continuously provided at the tip of the linear portion 417a.
According to the patch antenna 410, the current flows around the rectangular portion 417b in a detour compared to the case of the slit formed only by the linear portion 417a, so that the current path can be made longer.

FIG. 12 shows a second modification of the patch antenna.
In the patch antenna 510, a planar radiation electrode 513 is formed on the upper surface of a rectangular dielectric plate 514, a ground electrode (not shown) is formed on the lower surface of the dielectric plate 514, and the planar radiation electrode 513 is formed by a power supply member 516. Is being fed.
In the patch antenna 510, the slit 517 is composed of a linear portion 517a having a ridge width and a circular portion 517b continuously provided at the tip of the linear portion 517b.
According to the patch antenna 510, the current flows around the circular portion 517b as compared with the case of the slit formed only by the linear portion 517a, so that the current path can be made longer.

FIG. 13 shows a third modification of the patch antenna.
In the patch antenna 610, a planar radiation electrode 613 is formed on the upper surface of a rectangular dielectric plate 614, a ground electrode (not shown) is formed on the lower surface of the dielectric plate 614, and the planar radiation electrode 613 is formed by a power supply member 616. Is being fed.
In the patch antenna 610, the slit 617 is composed of a straight portion 617a having a ridge width and a straight portion 617b that is connected to the tip of the straight portion 617a and crosses the middle of the straight portion 617b.
According to the patch antenna 610, the current flows around the other linear portion 617b in a detour compared to the case of the slit including only the linear portion 617a, so that the current path can be made longer. it can.

As mentioned above, although some embodiment of this invention was described, the scope of the present invention is not limited to the above-mentioned embodiment, The range of the invention described in the claim, and its equivalent range including.
For example, in the above embodiment and the modification, the planar shape of the planar radiation electrode is a rectangle,
It may be a square, a circle, an ellipse, or the like.
In this embodiment, the longitudinal length of the rectangular planar radiation electrode, the lateral length, the longitudinal length of the rectangular dielectric plate, the lateral length, the thickness, the slit length However, as described above, the dimensions are not limited to these dimensions, and may be other dimensions.

The invention described in the scope of claims attached to the application of this application will be added below.
The item numbers of the claims described in the appendix are as set forth in the claims attached to the application of this application.
[Appendix]
<Claim 1>
Patch antenna device comprising a rectangular dielectric plate, a planar radiation electrode disposed on one surface of the rectangular dielectric plate, a ground electrode disposed on the other surface of the rectangular dielectric plate, and a feeding member In
The planar radiation electrode includes at least one slit extending in a portion corresponding to two opposite sides of the rectangular dielectric plate toward a portion corresponding to the other two opposite sides,
The patch antenna device according to claim 1, wherein a feeding position of the feeding member to the planar radiation electrode is offset from a center of the planar radiation electrode so as to obtain circular polarization characteristics.
<Claim 2>
2. The patch antenna according to claim 1, wherein the planar radiation electrode has any one of a circular shape, an elliptical shape, and a rectangular shape having sides parallel to the sides of the rectangular dielectric plate. apparatus.
<Claim 3>
The at least one slit is two or three slits, and these slits are formed on the two opposite sides from a portion corresponding to a central position of two opposite sides of the rectangular dielectric plate. The patch antenna device according to claim 1, wherein the patch antenna device extends toward a portion corresponding to the other two opposite sides orthogonal to each other.
<Claim 4>
The patch antenna device according to claim 3, wherein, of the three slits, the length of one central slit is shorter than the lengths of the other two slits.
<Claim 5>
5. The patch antenna device according to claim 1, wherein the rectangular dielectric plate has a long side and a short side, and the slit is provided on the short side. 6.
<Claim 6>
A radio wave receiving device comprising the device main body including the patch antenna device according to any one of claims 1 to 5.
<Claim 7>
The feeding position of the feeding member to the planar radiation electrode is a position on a straight line inclined by 45 ° with respect to an axis passing through the center of the planar radiation electrode and parallel to the short side of the planar radiation electrode, and having an appropriate impedance. A patch antenna device characterized by being set at a position.

100, 200 Antenna devices 110, 410, 510, 610 Patch antenna 113, 213 Planar radiation electrodes 114, 214 Dielectric plates 115, 215 Ground electrodes 117, 217 Slit 201 Equipment body

The patch antenna device according to the present invention is
Induction collector plates, induction collector plate one surface arranged plane radiation electrode of this, before Ki誘 collector plate other side to the earth electrodes arranged in, in the patch antenna device has a feeding member ,
The planar radiation electrode is:
A first length of slits provided in the portion corresponding to the two sides facing each other before Ki誘 collector plate,
A second length slit having a shorter length than the first length slit;
With
Characterized Rukoto changing the two resonant frequencies by providing the said the first length of the slit second length of the slit.
The radio wave receiving apparatus according to the present invention is characterized by being provided with the above-mentioned patch antenna device to the device body.

According to the present invention, it is possible to realize a high-gain patch antenna device and radio wave receiving apparatus that are adjusted to obtain good circular polarization characteristics with a simple configuration.

Claims (6)

Patch antenna device comprising a rectangular dielectric plate, a planar radiation electrode disposed on one surface of the rectangular dielectric plate, a ground electrode disposed on the other surface of the rectangular dielectric plate, and a feeding member In
The planar radiation electrode is:
A slit having a first length extending toward a portion corresponding to the opposite side of the opposite side of the rectangular dielectric plate;
A second length slit having a shorter length than the first length slit;
With
A patch antenna device characterized in that a shift between two resonance frequencies is reduced by providing the slit having the first length and the slit having the second length. 2. The patch antenna according to claim 1, wherein the planar radiation electrode has any one of a circular shape, an elliptical shape, and a rectangular shape having sides parallel to the sides of the rectangular dielectric plate. apparatus. 3. The patch antenna device according to claim 1, wherein the second length slit is provided at a position intersecting with the first length slit. 4. The rectangular dielectric plate includes a long side and a short side, and the first length slit and the second length slit are provided on a short side. Item 4. The patch antenna device according to any one of Items 1 to 3. A radio wave receiving device comprising the device main body including the patch antenna device according to any one of claims 1 to 4. The planar radiation electrode has a rectangular shape and has a long side and a short side, and a feeding position of the feeding member to the planar radiation electrode passes through the center of the planar radiation electrode and is parallel to the short side of the planar radiation electrode. The patch antenna device according to any one of claims 1 to 4, wherein the patch antenna device is set at a position on a straight line inclined by 45 ° with respect to the axis and at an appropriate impedance.

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