JPH09312515A - Shared polarized wave planar antenna - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shared polarized wave planar antenna being superior in a cross polarization characteristics and in an isolation wide-band characteristic to relieve load on a signal processing circuit at a planar antenna side. SOLUTION: A radiation element 3 is electromagnetically connected to the radiation element 7 and the exciting direction of the radiation element 3 by a power feeder line 4 is orthogonally crossed with the exciting direction of the radiation element 7 by the power feeder line 8 in the shared polarized wave plane antenna. In the antenna, about a half of the number of elements formed in a first power feeder substrate is rotated by 180 deg. in terms of space and arranged against a reference exciting direction and, moreover, an excitation is executed by electrically changing a power phase by 180 deg..

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dual-polarization plane antenna used for microwave band satellite communication, wireless communication and the like.

[0002]

2. Description of the Related Art In satellite communication in the microwave band, it is necessary to switch vertical and horizontal polarized waves for each receiving channel, and also in wireless communication and the like, transmission and reception can be handled by switching polarized waves. Antennas that can share polarized waves have been developed. The present inventors have already electromagnetically coupled the radiating element 3 and the radiating element 7 with a configuration as shown in FIGS. 6 and 7 as a planar antenna of this type, and
An antenna is proposed in which the direction of excitation of the radiating element 3 by the power feeding line 4 and the direction of excitation of the radiating element 7 by the power feeding line 8 are orthogonal to each other and sharing of polarized waves is possible.

[0003]

When designing an antenna having a structure as shown in FIGS. 6 and 7, the radiating elements 3 and 7 are excited by the polarization directions of the first and second feeding substrates 5 and 9. It is determined by the feeding direction of the feeding lines 4 and 8, and generally, the feeding direction of the feeding lines 4 and 8 is fed from the same direction as the reference excitation direction for each feeding board, and each radiating element is excited in the same phase. are doing. However, the dual-polarized plane antenna having such a configuration has a narrow cross-polarization characteristic as shown in FIG. 9, and is affected by the cross-polarization characteristic, and thus has the same cross-polarization characteristic as shown in FIG. In the array in the excitation direction, unnecessary radiation from the power feeding line portion exposed inside the slot 14 formed in the first power feeding substrate acts as a cross polarization component, so that the frequency characteristic becomes a narrow band and the frequency other than the design frequency is used. However, there is a problem that the cross polarization characteristics deteriorate and the isolation sharply deteriorates. In order to solve this problem, an isolator or the like having a high degree of isolation is required in the circuit system for signal separation of each polarized wave, and the signal processing circuit becomes complicated and expensive.

The present invention provides a dual-polarization plane antenna having a cross-polarization characteristic and a wideband characteristic of isolation in order to reduce the load on the signal processing circuit on the side of the plane antenna as much as possible.

[0005]

As shown in FIG. 1, a dual polarization plane antenna of the present invention includes a ground conductor 11 and a dielectric 1.
0, the feeding substrate 9 on which a plurality of radiating elements 7 and the feeding line 8 are formed, the dielectric 6, and each slot 12 are the radiating element 7
A ground conductor 1 having a plurality of slots 12 installed so as to be located right above, a dielectric 2, a feeding substrate 5 having a plurality of radiating elements 3 and a feeding line 4, a dielectric 13, and each slot. A ground conductor 15 having a plurality of slots 14 installed so that 14 is located right above the radiating element 3 is stacked in this order to electromagnetically couple the radiating element 3 and the radiating element 7 and to the feed line. In the dual polarized plane antenna configured so that the excitation direction of the radiating element 3 according to 4 and the excitation direction of the radiating element 7 according to the feed line 8 are orthogonal to each other, as shown in FIG. 3, the element formed on the first feed substrate. About half of the number is spatially rotated 180 degrees with respect to the reference excitation direction, and they are electrically excited by changing the feeding phase of 180 degrees electrically.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION A ground having a plurality of radiating elements 7 and a feeding board 9 on which a feeding line 8 is formed, and a plurality of slots 12 installed so that each slot 12 is located right above the radiating element 7. Instead of the conductor 1, a power supply board 9 having a plurality of microstrip lines 18 formed therein and each slit 1
It is possible to use the ground conductor 1 having a plurality of slits 19 arranged so that 9 intersects directly above the microstrip line 18.

As shown in FIG. 3, the dual-polarization planar antenna of the present invention has about half of the power feeding elements arranged on the first power feeding substrate spatially 180 degrees with respect to the reference excitation direction.
By arranging them by rotating them by 180 degrees and electrically exciting them by changing the phase by 180 degrees, as shown in FIG.
It is possible to cancel the unwanted radiation 19 generated from the exposed feed line portion inside the slot 14 formed in the feed board of, and as shown in FIG. 5, it is possible to secure a cross polarization characteristic in a wide band. Moreover, the isolation characteristic can be suppressed to a low level over a wide band.

[0008]

【Example】

Example 1 As shown in FIG. 1, as ground conductors 1 and 15 and 11,
The thickness is 1.0 mm and the size is 200 mm x 200 mm.
Dielectrics 2, 6, 10 and 13 using the aluminum plate of
As the power supply boards 5 and 9, a polyethylene foam having a thickness of 1 mm and a relative permittivity of about 1.1 is used.
A substrate in which a 35 μm-thick copper foil was attached to a 5 μm PET film was used. An antenna circuit including the radiating element 3 and the feeding line 4 is formed on the feeding board 5, and an antenna circuit including the radiating element 7 and the feeding line 8 is formed on the feeding board 9 by etching away unnecessary portions of the copper foil. did. Further, slots 12 and 14 were formed by press punching at positions corresponding to the radiating elements 3 and 7 of the ground conductors 1 and 15, respectively. With the above configuration, the radiating elements 3 and 7 and the slots 12 and 14 are arranged in 64 elements, and 32 radiating elements 3 which are about half the number of arrays formed on the feeding substrate 5 are provided.
Further, the feed line 4 was spatially rotated by 180 degrees, and power was fed to each feed line 4 by electrically changing the phase difference of 180 degrees at the center. The array spacing in two orthogonal directions was such that the polarization direction of the use frequency fL was about 0.9 times the free space wavelength λL, and the polarization direction of the use frequency fH was about 0.9 times the free space wavelength λH. Further, the dimensions of the radiating element 3 are 0.39λL in the excitation direction and 0.25λL in the non-excitation direction,
The dimensions of the radiating element 7 are 0.29λH in the excitation direction and 0.29λH in the non-excitation direction, and the slots 12 and 14 are
Was a square having sides of 0.57λL and 0.68λH. Regarding the cross polarization protection ratio and the isolation characteristic of this plane antenna, as shown in FIG. 5, in the band from fL to fH, good characteristics of cross polarization protection ratio of -30 dB or less and isolation of -40 dB or less are obtained. Was obtained.

Example 2 Referring to FIG. 2, as the ground conductors 1, 15 and 11, an aluminum plate having a thickness of 1.0 mm and a size of 200 mm × 200 mm is used, and the dielectrics 2, 6, 10 and 13 are used. , Polyethylene foam having a relative permittivity of about 1.1 and a thickness of 1 mm is used.
5 μm polyethylene terephthalate film with a thickness of 3
A substrate to which a copper foil of 5 μm was attached was used. Power supply board 5
The antenna circuit composed of the radiating element 3 and the power feeding line 4 was formed on the power feeding substrate 9, and the circuit of the microstrip line 18 was formed on the power feeding substrate 9 by etching away unnecessary portions of the copper foil. Also, the radiating element 3 of the ground conductors 1 and 15
Slots 14 and slits 18 were formed by press punching at locations corresponding to. With this configuration,
The radiating element 3, the microstrip line 18, the slot 14, and the slit 19 are arranged in an array number of 64, and 32 of the radiating elements 3 and the feeding line 4 out of the array number formed on the feeding substrate 5 are radiated by other 32 elements. The device 3 and the feed line 4 are spatially rotated 180 degrees, and
In the feed line 4 connected to the radiating element 3 of the element, another 32
The power supply line 4 connected to the radiating element 3 of the element was electrically changed in phase by 180 degrees and supplied. The array spacing in the two orthogonal directions was such that the polarization direction of the use frequency fL was about 0.9 times the free space wavelength λL, and the polarization direction of the use frequency fH was about 0.9 times the free space wavelength λH. Further, the dimensions of the radiating element 3 are 0.39λL in the excitation direction and 0.25λL in the non-excitation direction, and the slot 14 is 0.57 on one side.
The squares were λL and 0.68λH. The size of the microstrip line 18 is 0.04λL,
The dimensions of the slit 19 were 0.12 λL in the excitation direction and 0.32 λL in the non-excitation direction, and impedance matching adjustment was performed. The cross polarization protection ratio and the isolation characteristic of this planar antenna were as good as those of Example 1.

[0010]

As described above, according to the present invention, it is possible to provide an excellent dual-polarization planar antenna which can secure a cross polarization protection ratio and isolation in a wide band.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a perspective view showing another embodiment of the present invention.

FIG. 3 is a schematic connection diagram showing a main part of FIGS.

FIG. 4 is a cross-sectional view for explaining the operation of the present invention.

FIG. 5 is a diagram showing characteristics for explaining an effect of one embodiment of the present invention.

FIG. 6 is a perspective view showing a conventional example.

FIG. 7 is a perspective view showing another conventional example.

FIG. 8 is a cross-sectional view for explaining the problems of the conventional example.

FIG. 9 is a diagram showing characteristics for explaining the problems of the conventional example.

[Explanation of symbols]

1, 11, 15. Ground conductor 2, 6, 1
0, 13. Dielectric 3,7. Radiating element 4, 8. Power supply line 5, 9. Power supply board 12, 14.
Slot 16. First planar antenna 17. Second planar antenna 18. Microstrip line 19. Slit 20. Unwanted radiation

Claims (2)

[Claims] A feeder board on which a plurality of radiating elements and a feeder line are formed;
And a ground conductor 1 having a plurality of slots 12 installed such that each slot 12 is located directly above the radiating element 7.
, A dielectric 2, a feed substrate 5 on which a plurality of radiating elements 3 and a feed line 4 are formed, a dielectric 13, and a plurality of slots provided such that each slot 14 is located directly above the radiating element 3. And a ground conductor 15 having a radiating element 14 are stacked in this order, and the radiating element 3 and the radiating element 7 are electromagnetically coupled,
In addition, in the polarized wave common plane antenna configured so that the excitation direction of the radiating element 3 by the feed line 4 and the excitation direction of the radiating element 7 by the feed line 8 are orthogonal to each other, the array elements of the feed substrate 5 and the feed substrate 9 are arranged. Of the radiating elements and feed lines corresponding to about half the number of elements, or radiating elements and feed lines corresponding to about half the number of array elements on one of the feeding boards It is rotated 180 degrees to the
A polarized dual-purpose planar antenna characterized by being excited by being changed by 0 degree. 2. A ground conductor 11, a dielectric 10, a feeding substrate 9 having a plurality of microstrip lines 18, a dielectric 6, and each slit 19 so as to intersect directly above the microstrip line 18. Ground conductor 1 having a plurality of slits 19 installed in the dielectric body, a dielectric body 2, a feeding substrate 5 having a plurality of radiating elements 3 and a feeding line 4, and a dielectric body 1.
3 and a ground conductor 15 having a plurality of slots 14 installed so that each slot 14 is located directly above the radiating element 3, and are stacked in this order, and are composed of the intersecting microstrip lines 18 and slits 19. The unit and the radiating element 3 are electromagnetically coupled to each other, and the feeding line 4
In the plane antenna for dual polarization, which is configured so that the excitation direction of the radiating element 3 and the excitation direction of the unit consisting of the microstrip line 18 and the slit 19 which intersect with each other are orthogonal to each other, Radiation corresponding to about half the number of radiating elements 3 and feeding lines 4 corresponding to the number of elements and the microstrip line 18 formed on the feeding board 9, or about half the number of array elements on one of the feeding boards. Element 3 and feed line 4
Alternatively, about half of the microstrip line 18 is spatially rotated 180 degrees with respect to the reference excitation direction, and electrically excited by changing the feeding phase by 180 degrees. .