JPH0865037A - Antenna shared by right and left-handled circularly polarized waves - Google Patents

Abstract

PURPOSE: To provide an antenna shared by right and left-handed circularly polarized waves of which the for preventing isolation and the axial ratio will not be degraded even when the distance between slots is made short. CONSTITUTION: This right-handed and left-handed shared circularly polarized wave antenna is constituted of a waveguide part, a first dielectric substrate 2 for which a patch antenna element 4 for receiving circularly polarized waves installed to the end part of the waveguide part is provided on one surface on the side of the waveguide part and a second dielectric substrate 3 installed on the other surface side of the first dielectric substrate 2 for which mutually orthogonally crossing slots 6 are provided on one surface on the side of the wave guide part and an approximately V-shaped feeder 7 orthogonally crossing the respective clots 6 is provided on the other surface side. The mutually orthogonally crossing slots 6 are turned to an L-shape.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a right-handed and left-handed circularly polarized antenna which can be used for both signals as a single unit for right-handed circularly polarized waves and left-handed circularly polarized waves.

[0002]

2. Description of the Related Art Conventionally, satellite receiver antennas are
For right-handed and left-handed circularly polarized waves, there is a right-handed and left-handed circularly polarized antenna that can be used for both signals. As the antenna, as shown in FIGS. 5 (A) and 5 (B), a waveguide portion 12 to which the other end of the electromagnetic horn portion 1 having one end opened is connected, and the other end of the waveguide portion 12 Part of the first dielectric substrate 2 and a patch antenna element 4 made of, for example, a rectangular conductor and having an adjusted phase characteristic, provided on one surface of the substrate 2 facing the electromagnetic horn portion 1. A second dielectric substrate 3 installed close to the other surface side of the first dielectric substrate 2 and a ground conductor 9 provided on one surface of the dielectric substrate 3 on the electromagnetic horn portion 1 side. When,
Slots 5 and 6 provided in the ground conductor 9 at right angles to each other, and feeders 7 and 8 provided on the other surface of the dielectric substrate 3 and independently provided for each of the slots 5 and 6, The power supply lines 7 and 8 are connected to the slots 5 and 6 at required power supply positions, and right-handed or left-handed circularly polarized waves are extracted from the respective power supply lines. However, as shown in FIG. 6, when the slots 5 and 6 are brought close to each other, for example, a combined electric field E of right-handed (or left-handed) radio waves on one side to be coupled with the slot 6 is obtained.
Components EX and EY of the above are also coupled to the left-handed (or right-handed) radio wave slot 5 on the other side through the conductor portion 20 between the slots, and due to this electromagnetic interference, the left-handed (or right-handed) radio wave feeder 7 also has a problem that a right-handed (or left-handed) radio wave is extracted and the isolation (cross polarization characteristic) and the axial ratio (circular polarization rate) are poor. FIG. 7 is an example of an experimental result showing the above-mentioned problem, in which the vertical axis 50 in (A) is isolation, the horizontal axis is frequency 51, and the power supplied to the one power supply line is 0 (dB). And the amount of electric power supplied to the other power supply line is shown by the curve 52, and the minimum value is about −20 (d
B), and the vertical axis 60 in (B) is the axial ratio (dB) that indicates the circular polarization rate that represents the value of b / a when the minor axis of the ellipse is a and the major axis is b. And the horizontal axis is frequency 61,
In an ideal circularly polarized wave, the above b / a should be 1, and the conventional experimental result shows that it is about 3 (dB) or more (b / a).
It can be seen that a = 2 or more) and elliptically polarized waves are obtained.

[0003]

As described above, according to the experimental results when the distances of the respective slots are made close to each other, the isolation is about -20 at the desired frequency f.
(DB), the axial ratio is 3 (dB) or more, which is far from the ideal circular polarization. Therefore, in view of the above problems, the present invention provides isolation even if the distance between slots is reduced. Another object of the present invention is to provide a circularly polarized antenna for both right-handed and left-handed rotation that does not deteriorate the axial ratio.

[0004]

In order to achieve the above object, the present invention provides a waveguide section and a circular polarization receiving patch antenna element installed at the end of the waveguide section. The first dielectric substrate provided on one surface of the tube portion side and the other surface side of the first dielectric substrate are provided with slots orthogonal to each other on the one surface of the waveguide portion side and the other surface side. In a slot-fed right / left-handed circularly polarized patch antenna composed of a second dielectric substrate having a substantially V-shaped feed line orthogonal to each of the slots, the mutually orthogonal slots are L-shaped. It is characterized by

[0005]

With the above-mentioned structure, the right-handed and left-handed circularly polarized antenna according to the present invention has one end of each slot coupled to form an L-shape, and the conductor portion between the slots is removed to bring the slots closer together. Since the coupling between each slot and the patch antenna element is strengthened, the right-handed (or left-handed) circularly polarized wave that is coupled in one slot is not coupled with the other slot, and the cross-polarized characteristic is Properties and circular polarizability will not deteriorate.

[0006]

1 (A) and 1 (B) are views showing an embodiment of a circularly polarized feed horn according to the present invention. Reference numeral 1 is an electromagnetic horn portion having one end opened and the other end connected to the waveguide portion 12. Reference numeral 12 is a waveguide portion whose one end is connected to the electromagnetic horn portion 1. Reference numeral 2 denotes a first dielectric substrate installed at the other end of the waveguide unit 11, and a patch antenna having a phase characteristic adjusted, for example, on one surface of the substrate 2 facing the electromagnetic horn unit 1. An analog element 4 is provided. 3 is
It is a second dielectric substrate placed close to the other surface side of the first dielectric substrate 2, and a ground conductor 9 is provided on one surface of the dielectric substrate 3 on the electromagnetic horn portion 1 side. L-shaped slots 5 and 6 orthogonal to each other in the same ground conductor 9
In addition, the independent feeding lines 7 and 8 are provided on the other surface for the slots 5 and 6, respectively, and the feeding lines 7 and 8 are connected to the slots 5 and 6 at required feeding positions.

Next, the operation of the circularly polarized feed horn having the above structure will be described. In FIG. 2, the patch antenna element 4 which connects the power supply lines 7 and 8 at a required position is arranged between two component signals of the received circular polarization signal (right-hand circular polarization signal or left-hand circular polarization signal). Removes the phase difference and converts linear polarization. For example, when a right-handed circularly polarized signal (left-handed circularly polarized signal) is radiated from the vertical slot of the slot 6, a vertically (or horizontally) polarized signal is taken out from the feeder line 8. . When the right-handed circularly polarized signal (left-handed circularly polarized signal) is radiated from the horizontal slot of the slot 5, another signal obtained by the other horizontal (or vertical) polarization conversion from the feed line 7 is taken out. To be done. Since the slot is formed in an L shape and the patch antenna elements are coupled to each other, for example, the circularly polarized wave coupled to the slot 5 is coupled to the slot 6, or conversely, coupled to the slot 6. The circular polarization does not couple with the slot 5, and the cross polarization characteristic and the circular polarization rate do not deteriorate. FIG.
Is the measurement result of the isolation and axial ratio by the L-shaped slot configured as described above, the vertical axis 50 of (A) is the isolation (dB), the horizontal axis is the frequency 51, and the one of the feeding lines is The power supplied is 0 (dB), and the amount of power supplied to the other power supply line is shown by the curve 52. The isolation of about -35 (dB) is obtained at the desired frequency f. Obtained (about 20d than the conventional one
B is improved), and the vertical axis 60 in FIG. 7B is an axial ratio (dB) indicating the circular polarization rate that represents the value of b / a when the minor axis of the ellipse is a and the major axis is b. The horizontal axis represents frequency 61, and in ideal circular polarization, b / a should be equal to ± 0 (dB), and almost ideal circular polarization was obtained.

As the shape of the patch antenna element 4, as shown in FIG. 4, the shape of the patch antenna element 4 may be the one obtained by adjusting the required phase characteristics by making a necessary cut in the outer shape of the circular conductor. It is also possible to widen the band by stacking a plurality of dielectric substrates provided with patch antenna elements.

[0009]

As described above, in the present invention, one end of the slots which are orthogonal to each other are coupled to each other to form an L-shape, so that each slot is strongly coupled to the patch antenna element, and the slots are mutually coupled. The coupling between the slots becomes stronger, the cross polarization characteristics and the circular polarization rate do not deteriorate, and the shape of the circular polarization feed horn can be made smaller.

[Brief description of drawings]

FIG. 1A is a cutaway view showing an embodiment of a circularly polarized wave receiving feed horn of the present invention, and FIG. 1B is a sectional view thereof.

FIG. 2 is a diagram showing the shape of slots of a feed horn for circularly polarized light for both left-handed and right-handed rotation of the present invention.

FIG. 3 is data of an experimental result by the feed horn for circular polarization for both right-handed and left-handed rotation of the present invention.

FIG. 4 is a view of another embodiment of the shape of the slot of the right-handed and left-handed circularly polarized feed horn of the present invention.

5A is a cutaway view showing an example of a conventional feed horn for receiving circularly polarized waves, and FIG. 5B is a sectional view thereof.

FIG. 6 is a diagram illustrating a slot arrangement of a conventional feed horn for receiving circularly polarized waves.

FIG. 7 is data of an experimental result by a conventional feed horn for circular polarization for both left-handed and right-handed rotation.

[Explanation of symbols]

 1 Electromagnetic Horn 2 Dielectric Substrate 3 Dielectric Substrate 4 Patch Antenna Element 5 Slot 6 Slot 7 Stripline 8 Stripline 9 Ground Conductor

Claims (6)

[Claims] 1. A waveguide part, and a first dielectric substrate having a circularly polarized wave reception patch antenna element installed at an end of the waveguide part on one surface of the waveguide part side. , A substantially V-shaped feeder line that is installed on the other surface side of the first dielectric substrate and is provided on one surface of the waveguide portion side that is orthogonal to each other and that is orthogonal to the respective slots on the other surface side. In a slot-fed right-handed left-handed circularly polarized patch antenna composed of a second dielectric substrate provided with, said right-handed left-handed circularly polarized antenna is characterized in that said mutually orthogonal slots are L-shaped. 2. The circularly polarized antenna for both left-handed and right-handed rotation according to claim 1, wherein the patch antenna element for receiving the circularly polarized wave is composed of a rectangular radiation circuit pattern. 3. The angle formed by the center line parallel to one side of the rectangular radiation circuit pattern and the substantially V-shaped open portion of the feeding slot is arranged at 45 degrees. A circularly polarized antenna for both right-handed and left-handed use. 4. The patch antenna element for receiving circularly polarized waves comprises a substantially circular radiating circuit pattern in which a pair of degenerate separation notches are provided at circumferentially opposed positions. A circularly polarized antenna for both left-handed and right-handed use according to item 1. 5. The angle formed by the center line connecting the centers of the degenerate separation notches and the substantially V-shaped open portion of the power feeding slot is arranged at 45 degrees. Item 4. The circularly polarized antenna for left-right rotation according to item 4. 6. A plurality of dielectric substrates provided with the patch antenna element are stacked and installed.
A circularly polarized antenna for both right-handed and left-handed use.