JP2806350B2 - Patch type array antenna device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna device, and more particularly to a patch type array antenna device for directivity synthesis in a microwave / millimeter wave band.

[0002]

2. Description of the Related Art A conventional patch-type array antenna apparatus comprises a fed patch antenna and a parasitic patch antenna placed on both sides thereof, and the parasitic patch antenna is provided with a stub for phase adjustment. ing. For example,
FIG. 5 shows an example of a conventional antenna device of this type. 334-336. 5A is a plan view, and FIG. 5B is a cross-sectional view. A patch antenna 11 is provided on the surface of a dielectric 14 and parasitic patch antennas 12 and 13 are provided on both sides thereof.
Are formed, and a ground plate 15 is formed on the back surface of the dielectric 14. And the patch antenna 11 is a dielectric 14
Power is supplied from the back side through a pin 17 penetrating through. The signal fed to the patch antenna 11 excites the parasitic patch antennas 12 and 13 by electromagnetic coupling,
19 causes the excitation current to be phase shifted.

At this time, patch antennas 11, 12, 1
3 operates as an array antenna having an excitation current of a11 a12 × exp (j (φ12 + φ18)) a13 × exp (j (φ13 + φ19)). Here, φ12, φ
Reference numeral 13 denotes an amount of phase shift caused by electromagnetic coupling, which is determined by the arrangement of the patch antennas 11, 12, and 13. φ18, φ1
9 is the phase shift amount by the stubs 18 and 19,
Determined by length of 9. Therefore, patch antenna 1
The directivity synthesis can be performed by adjusting the excitation current distribution according to the arrangement of 1, 12, 13 and the length of the stubs 18, 19.

[0004]

However, such a conventional antenna has the following problems. First
The problem is that the directivity of the antenna is disturbed. The reason is that the stub is provided in the same plane as the antenna,
This is because unnecessary radiation from the stub disturbs the directivity of the antenna. The second problem is that mechanical restrictions on the arrangement of the antennas are increased. The reason for this is that if a stub is provided in the same plane as the antenna, the stub protrudes from the parasitic patch antenna, causing mechanical interference with an adjacent element antenna. A third problem is that it cannot be applied to circularly polarized antennas. The reason is that it is necessary to provide stubs on two orthogonal surfaces of the parasitic patch antenna, which causes mechanical interference with the adjacent element antenna.

An object of the present invention is to increase the degree of freedom in the arrangement of patch antennas, to increase the degree of freedom in directivity synthesis, to apply to circularly polarized waves, and to improve the directivity by unnecessary radiation from a stub. It is an object of the present invention to provide a patch-type array antenna in which deterioration of performance is improved.

[0006]

SUMMARY OF THE INVENTION The present invention provides a powered 1
One patch antenna, and four parasitic patch antennas respectively arranged on both sides in one direction of the patch antenna and on both sides in the other direction orthogonal to the patch antenna. Patch ante
On the same surface of a dielectric with a ground plate on the back.
The power supply patch antenna and the parasitic patch antenna are arranged at different resonance frequencies.
For example, the resonance frequency of the non-feeding patch antenna is changed by changing its size, and the resonance frequency of the non-feeding patch antenna is different from that of the feeding patch antenna. Here, the feeding patch antenna may be configured as a circularly polarized patch antenna.

[0007]

Next, embodiments of the present invention will be described with reference to the drawings. FIGS. 1A and 1B show the basics of the present invention.
It is the top view and sectional drawing which show a structure . A ground plate 5 is formed on the back surface of the dielectric 4, and patch antennas 1, 2, 3 made of a metal thin film are formed on the surface of the dielectric 4.
The central patch antenna 1 is formed in a square shape,
Power is supplied via a power supply pin 7 from a connector 6 protruding to the back side of the power supply. Also, patch antennas 2 and 3 on both sides
Is configured as a parasitic patch antenna, and is formed in a square having slightly smaller vertical and horizontal dimensions than the patch antenna 1.
Here, the resonance frequency of the patch antenna 1 is f1, and the resonance frequency f2 (≠ f1) of the parasitic antennas 2 and 3.

FIG. 2 shows the frequency characteristic of the impedance of each of the patch antennas 1, 2, and 3. In the figure, 1
01, 201 and 301 are the conductance components of the respective impedances, and 102, 202 and 302 are the susceptance components of the respective impedances. here,
When the patch antenna 1 is excited by the signal of the frequency f1, the parasitic antennas 2 and 3 are also driven by the frequency f1 by electromagnetic coupling.
Excited by Since the resonance frequency of the parasitic patch antennas 2 and 3 is f2, the parasitic patch antennas 2 and 3 have a susceptance component as shown in FIG. 2, and the excitation current of the parasitic patch antennas 2 and 3 is reduced by the susceptance component. Phase shifted. Here, each of the patch antennas 1, 2, and 3 operates as an array antenna having an excitation current of a1 a2 × exp (φ21 + φ2) a3 × exp (φ31 + φ3). Note that φ21, φ3
1 is a phase shift amount caused by electromagnetic coupling, and φ2 and φ3 are phase shift amounts due to susceptance components of the parasitic antennas 2 and 3.

Here, the sizes of the parasitic patch antennas 2 and 3, here, the square parasitic patch antennas 2 and 3 are used.
When the resonance frequency f2 is changed by appropriately changing the vertical and horizontal dimensions of No.3, the susceptance component changes, and φ2 and φ3 can be adjusted. That is, directivity synthesis can be performed by adjusting the size of the parasitic antennas 2 and 3.

As described above, in this antenna, the phase of the excitation current is adjusted by adjusting the size of the non-feeding patch antennas 2 and 3 arranged on both sides of the fed patch antenna 1 to change the resonance frequency. Therefore, there is nothing protruding outside the patch antenna, mechanical interference is eliminated, mechanical restrictions on the arrangement of element antennas are reduced, and the degree of freedom in antenna arrangement can be increased. Further, since there is no need to attach a stub to the element antenna, the directivity is not disturbed.

FIG. 3 is a plan view of the first embodiment of the present invention, and the sectional structure is the same as the basic configuration shown in FIG.
In this embodiment, that a parasitic patch antenna 2 and 3 are formed in the X direction on both sides of the patch antenna 1 is the group
Is the same as the structure, the Y-direction sides of the patch antenna 1 parasitic patch antenna 8, 9 are formed. In this configuration , the basic configuration has been described with reference to FIGS.
The directivity synthesis can be performed as described above. However, the directivity synthesis on the XZ plane can be performed by the parasitic patch antennas 2 and 3, and the YZ synthesis can be performed by the
Directional synthesis of planes can be performed.

[0012] Figure 4 is a second in which the invention is applied to a circularly polarized radiation
It is a top view of an embodiment. In this embodiment, the fed patch antenna 1 of the antenna device shown in FIG. 3 is replaced with a circularly polarized patch antenna 10. In this configuration, directivity synthesis on the XZ plane is performed by parasitic patch antennas 2 and 3, and Y-direction is synthesized by parasitic patch antennas 8 and 9.
Directivity synthesis of the Z plane can be performed. In addition, since it is not necessary to provide a stub for two orthogonal surfaces, the antenna can be arranged without mechanical interference. In addition, since a circularly polarized patch antenna is used, the antenna can be applied to circularly polarized radiation. Becomes possible.

In the above embodiments, the case where the shape of the patch antenna is a square has been described. However, the present invention can be applied to a circular shape.

[0014]

As described above, according to the present invention, the resonance frequencies of the non-feeding patch antennas arranged on both sides in one direction of one fed patch antenna and on both sides in the other direction orthogonal to the one patch antenna are determined. Since the resonance frequency is different from the resonance frequency of the fed patch antenna, the directivity synthesis can be performed in directions orthogonal to each other by changing the phase of the excitation current by changing the resonance frequency of the parasitic patch antenna. For this reason, it is not necessary to provide a stub on the antenna surface, and unnecessary radiation due to the stub is eliminated, and disturbance of the radiation pattern can be eliminated. In addition, the power supply patcher
Antenna and the parasitic patch antenna
Since it is located on the same surface of the dielectric with the plate,
Since the antenna can be formed flat and there is no protrusion from the outer shape of the antenna, the degree of freedom of the arrangement of the antenna is increased, and the degree of freedom of the directivity synthesis is increased. Furthermore, since there is no need to provide a stub for two orthogonal surfaces, the antenna can be arranged without mechanical interference, and the present invention is applied to circularly polarized radiation by using a circularly polarized patch antenna as a feeding patch antenna. There is an effect that can be.

[Brief description of the drawings]

FIG. 1 is a plan view and a sectional view of a basic configuration of the present invention.

FIG. 2 is a frequency characteristic diagram of each patch antenna in FIG. 1;

FIG. 3 is a plan view of the first embodiment of the present invention.

FIG. 4 is a plan view of a second embodiment of the present invention.

FIG. 5 is a plan view and a cross-sectional view of an example of a conventional patch-type array antenna.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Feeding patch antenna 2, 3 Parasitic patch antenna 4 Dielectric 5 Groud plate 6 Connector 8, 9 Parasitic patch antenna 10 Circularly polarized patch antenna

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H01Q 13/08 H01Q 1/32 H01Q 21/06

Claims (3)

(57) [Claims] 1. A power-fed patch antenna, and four non-fed patch antennas arranged on both sides in one direction of the patch antenna and on both sides in another direction orthogonal to the patch antenna. , The feeding patch antenna
And the parasitic patch antenna have a ground plate
A patch-type array antenna device which is disposed on the same surface of a dielectric material having the same, and wherein the feeding patch antenna and the non-feeding patch antenna have different resonance frequencies. Wherein said parasitic patch antenna, a patch-type array antenna system according to claim 1, the resonance frequency of the feeding patch antenna by changing its dimensions are different. 3. The patch-type array antenna device according to claim 1, wherein the feeding patch antenna is a circularly polarized patch antenna.