JPH02211703A - Circularly polarized wave antenna commonly usable for both polarized waves - Google Patents

Abstract

PURPOSE:To obtain a small-sized and high grain antenna with simple constitution by feeding patch elements on the same face by a feeding system. CONSTITUTION:With respect to an antenna 10, four one-point feed type square patch elements P1 to P4 loaded with degenerated separation elements are formed on the surface of a dielectric substrate 1 whose rear face an earth conductor plate is adhered to. Plane feeding for left-handed polarized wave and that for right-handed polarized wave to patch elements P1 to P4 are performed by the feeding system. Patch elements P1 to P4 function as circularly polarized wave antennas shared between both polarized waves. Thus, the high gain small-sized circularly polarized wave antenna commonly usable for both polarized waves is obtained.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a dual-polarized circularly polarized antenna capable of transmitting and receiving both right-handed circularly polarized waves and left-handed circularly polarized waves, which shares an antenna element, and further This invention relates to a small, dual-polarized circularly polarized antenna with a simplified feeding system and a good axial ratio.

(Prior Art) Conventionally, dual polarization circularly polarized antennas capable of transmitting and receiving both right-handed circularly polarized waves and left-handed circularly polarized waves have been made up of a horn-shaped antenna and a circular-to-linear converter.

Further, a circularly polarized antenna using a microstrip line that can share both polarizations is also known.

(Problem to be Solved by the Invention) However, in the case of the former of the above-mentioned conventional techniques, the circular-to-linear converter has the problem that the configuration is complicated due to the waveguide structure, and it is also expensive. There were also problems.

Further, the latter of the above-mentioned conventional techniques has a problem in that a power feeding system for feeding power to a plurality of antenna elements has not been devised.

An object of the present invention is to provide a high-gain, small-sized, dual-polarized circularly polarized antenna.

(Means for Solving the Problems) The dual-polarized circularly polarized antenna of the present invention includes a plurality of single-point feeding type patch elements forming a microstrip line circularly polarized antenna, and a left-handed circularly polarized wave antenna for feeding power to each patch element. It is characterized by comprising a feeding system for circularly polarized waves, a feeding system for right-handed circularly polarized waves, and a combiner having an isolator function at a branching point of the feeding system from the antenna feeding point to each patch element.

(Function) In the dual-polarized circularly polarized antenna configured as described above, when operating with right-handed circularly polarized waves, for example, due to isolation by the synthesizer, power is not supplied by the right-handed circularly polarized feeding system. No interference occurs via the left-handed circularly polarized feed system connected to the patch elements.

The same holds true when operating with left-handed circularly polarized waves.

(Example) This invention will be explained below with reference to Examples.

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

The antenna 10 of this embodiment is made of copper, for example, on which four single-point feeding type rectangular patch elements P1 to P4 loaded with degenerate separation elements are laminated on the surface of a dielectric substrate 1 with a ground conductor plate adhered to the back surface. It is formed by etching foil or the like.

The patch element PI-P4 is fed a plane power for left-handed circularly polarized waves and a plane power fed for right-handed circularly polarized waves by a power feeding system.

The feeding system includes a feeding line D11 that branches from the antenna feeding point A1 for left-handed circularly polarized waves and feeds the feeding point 331 of the patch element P, and a feeding line D11 that branches from the antenna feeding point A1 and feeds the patch element P.
It is equipped with a feed line D1□ that feeds power to the feed point S41 of Patch element P2, and is branched from the antenna feed point A2 for right-handed circularly polarized waves and feeds power to the feed point S of patch element P2.
g+, branched from antenna feeding point A2 to patch element P4
The power supply line D is provided to supply power to the power supply point S4□. Here, the feed line D8, I) tz, and the delay lines CI and C3 (described later) are the feed system for left-handed circularly polarized waves, and the feed line D
Yo1, D, ffi, delay line C below! and C1 constitute a power supply system for right-handed circularly polarized waves. Antenna feeding point A
Wilkinson type combiner B1 is installed at the feed system branch from I.
A Wilkinson combiner B2 is inserted in the feed system branch from the antenna feed point At, and the Wilkinson combiner B connects the feed line D to the patch element P by Dtt.

and P4, and the Wilkinson combiner B2 connects the power supply line D! The connection between patch elements P2 and P4 by IP and Dtt is isolated.

The power supply system has λg to match the phase of power supply to each patch.
/2 (λg is the in-line wavelength of the center frequency signal of the signal to be transmitted or received), and is equipped with a delay line CI""Ca, which connects the feed point Sll of the patch element P and the patch element P,
The feed point SS+ of the patch element P+ is connected by the delay line C1 to the feed point S1! of the patch element P+. and the feed point SZZ of patch element P2 is delay line C! Therefore, the patch element P! Feeding point S□
and the feed point S41 of the patch element P4 is the feed point S41 of the patch element P, by the delay line C1. and patch element P, feeding point S4. and are connected by a delay line C4.

In this embodiment configured as described above, each of the patch elements P1 to P4 acts as a dual-polarized circularly polarized antenna.

Now, when operating with right-handed circular polarization, the antenna feeding point A! Patch elements P2 and P4 are simultaneously supplied with power through a Wilkinson type combiner B2, and then power is supplied to patch element P with a delay of 180 degrees through delay lines C2 and C4.
1 and P are supplied simultaneously. However, the patch elements P! which are simultaneously supplied with power! and P4 are in phase, so
Furthermore, since patch elements P+ and P are in phase,
Delay lines CI and C serve as feed lines for left-handed circular polarization
No interference occurs through 1. In addition, the feed point SKI and 34
1 is the power supply line D because it is isolated by the Wilkinson combiner B1.

and DI! No interference occurs through. If the Wilkinson combiner Bt were not present, the patch elements P2, P4 and the patch elements Pt, Ps would not be supplied with power at the same time, so the power supply lines D11 and D1! will be interfered with through

However, since the Wilkinson combiner B1 is provided, interference is prevented and a right-handed circularly polarized antenna with a good axial ratio is obtained.

Conversely, when operating with left-handed circular polarization, the antenna feed point A is simultaneously fed to the patch elements P and B4 through the Wilkinson type combiner B, and is further fed to the delay line C.
1 and C3 with a 180 degree delay, patch elements P, and P! are simultaneously supplied with power. However, since the patch elements P and B4 that are simultaneously fed are in phase, and patch elements P1 and B2 are also in phase, the delay lines C2 and C4, which act as feed lines for right-handed circularly polarized waves, No interference occurs. Further, since the feed points SZZ and 34□ are isolated by the Wilkinson combiner Bt, no interference occurs through the feed lines DZI and 34□.

Therefore, since the Wilkinson combiner B2 is provided, interference is prevented and a left-handed circularly polarized wave antenna with a good axial ratio is obtained.

In addition, if there is no corner notch for loading a degenerate separation element in a rectangular patch (in the case of linear polarization), there is an eye and a tression between the feeding side and the sides on both sides orthogonal to it.
There is almost no interference. However, if a corner notch is provided to create a single-point feeding type circularly polarized antenna, the isolation between the side that includes the feeding point and the sides perpendicular to it will decrease, and one or both of the sides will Interference occurs when signals of different phases are applied. This interference significantly deteriorates the axial ratio.

However, as described above, according to this embodiment, no interference occurs and the axial ratio is good.

Also, in place of the patch elements P1 to P4 of this embodiment, a second
Even if the patch element U has a planar circular shape as shown in Figure (a) and has notches (■) at both ends of its diameter,
Even if the patch element W is rectangular in plan as shown in FIG. 2(c), the patch element
However, as shown in FIG. 2(d), the patch element Z may be rectangular in plan view and provided with a rectangular hollow portion R in the center. In FIG. 2, the black circles indicate the feeding points of the patch elements.

Furthermore, a modification of this embodiment is shown in FIG. The modified example shown in FIG. 3 includes patch elements P+ and Pl, feed line D1,
1 and Dlz, Wilkinson type synthesizer Bl, delay line C+, Cz and C4 are removed, patch element P2
Antenna feeding point A with feeding point S21 as another antenna feeding point.

The operation is similar to that of the circularly polarized antenna IO shown in FIG.

(Effects of the Invention) As explained above, according to the present invention, since the feeding system is simple, feeding can be performed on the same plane as the patch element, and a circularly polarized antenna that can share circularly polarized waves can be obtained with a simple configuration. can be miniaturized, and since almost no interference occurs, a good axial ratio can be obtained even for circularly polarized waves. Furthermore, the gain is high. Therefore, it is an ideal antenna for communication using circularly polarized waves.

[Brief explanation of the drawing]

FIG. 1 is a plan view of an embodiment of the invention. FIG. 2 is a plan view showing another example of the patch element. FIG. 3 is a plan view showing a modification of one embodiment of the invention. PI ~ P, , U, W, X and z... Bunch element, A I, A'r and A2... Antenna feed point, B, and B2... Wilkinson type combiner, 01~C4"' Delay line, D Il+D
,,. B21 and D2□...Power supply line. Patent applicant Kenwood Co., Ltd.

Claims (1)

[Claims] 1 forming a microstrip line circularly polarized antenna
Multiple patch elements of point feed type, left-handed circularly polarized wave feeding system and right-handed circularly polarized wave feeding system that feed power to each patch element, and isolator function at the branch point of the feeding system from the antenna feeding point to each patch element. A circularly polarized antenna for dual polarization.