JPS60217703A - Circulary polarized wave antenna - Google Patents

Abstract

PURPOSE:To obtain a circularly polarized wave antenna changing easily the rotating direction of a polarized wave by arranging four radiating elements in a cross form and feeding power to the elements placed orthogonally with a phase difference of 90 deg. with the variable degree of coupling. CONSTITUTION:The 1/4 wavelength radiating elements 101-104 are arranged in a cross form on the upper face of the dielectric board 200 and the radiating elements 101, 102 orthogonal mutually are fed by a microstrip line 400. The coupling of the feeding points C, D is varied by adjusting a screw 600 as shown in sectional view and the interval of the coupling points is selected to 1/4 wavelength. The polarized wave is rotated right or left depending on the feeding from the point E or the point F by using the said screw 600 to adjust the degree of coupling.

Description

Detailed Description of the Invention (Technical Field) The present invention relates to an antenna used for transmitting and receiving circularly polarized electromagnetic waves.

(Prior Art) A conventional antenna of this type is shown in a perspective view in FIG. This circularly polarized antenna consists of radiating elements 1 and 1' each having a length of approximately 1/4 wavelength, radiating elements 2 and 2' perpendicular to these elements, and a coaxial line for power feeding. The power feeding coaxial line consists of an outer conductor 3 and an inner conductor 4. A slit 6 is formed in the outer conductor 3), and the outer conductor 3 is divided into two at the tip. A tip 5 of the inner conductor 4 is connected to the outer conductor 3 near the radiating element. 2 is a top view of the radiating element portion of the circularly polarized antenna of FIG. 1. FIG. The connection shown in this figure allows transmission and reception of right-handed circularly polarized waves. However, in order to transmit and receive left-handed circularly polarized waves, it is necessary to change the relative positional relationship between the slit 6 and the tip 5 of the inner conductor 4 of the coaxial line to create a configuration as shown in the top view in FIG.

FIG. 4 is a perspective view of another example of a conventional antenna of this type. This circularly polarized antenna includes a square thin plate-shaped radiating element 10, a dielectric material 20. Consisting of a ground conductor (ground plate) 30 and power supply conductors 40 and 40', electromagnetic energy of equal power is transmitted from the power supply part (not shown) to the power supply points B and B' of the radiating element 10 with a phase difference of 90'' from each other. Power is supplied through the power supply conductors 40 and 40' so that

In addition, as a conventional antenna of this kind, there is one which is composed of a circularly polarized wave generator and a conical horn.

In these conventional antennas, it is either impossible to arbitrarily select and transmit or receive circularly polarized electromagnetic waves with desired turning characteristics, or the configuration becomes complicated. In the example shown in FIG. 1, the shape needs to be changed depending on the direction of rotation of polarized waves. In addition, the antenna in Figure 4 requires a circuit in the feed section (not shown) that divides the electromagnetic energy into equal-power electromagnetic energy with an appropriate phase difference. It requires a circularly polarized wave generator that generates circularly polarized waves. As described above, conventional antennas have the disadvantage that it is impossible to switch the direction of rotation of polarized waves or that the configuration is complicated.

(Object of the Invention) An object of the present invention is to provide a circularly polarized antenna in which the direction of rotation of polarized waves can be easily changed.

(Structure of the Invention) The structure of the circularly polarized antenna according to the present invention includes a microstrip line formed by fixing a ground plate and a strip conductor to the first and second wide surfaces of the first dielectric plate, respectively; This second dielectric plate is sandwiched between the first dielectric plate and the strip conductor, and the second dielectric plate that sandwiches the IJ tube conductor, and the strip conductor. A cross-shaped radiating element fixed to a wide surface of the body, and first and second coupling screws for adjusting the degree of electromagnetic coupling between the strip conductor and the radiating element. , the radiating element has four rectangular conductors each having an electrical length of approximately 1/4 of the length of the radiated radio wave arranged in a cross shape, and the first and second coupling screws have two conductors that are directly fired with each other The nine tab conductors are electromagnetically coupled to the strip conductor, and the first and second conductors are electromagnetically coupled to the rectangular conductor.
The distance between the connecting screws is approximately one-fourth of the wavelength in terms of electrical length.

(Example) Next, the present invention will be explained in detail with reference to Examples.

FIG. 5 is a perspective view of an embodiment of the present invention.

Numerals 101 to 104 are plate-shaped conductors arranged in a cross shape and each having an electrical length of approximately 174 wavelengths, and these four conductors form a cross-shaped radiating element. 200 and 210 are dielectric plates; 300 is a ground conductor (400 with a ground plate is a strip conductor for power feeding; the strip conductor 400 and the ground conductor 30
0 and the dielectric 210 constitute a microstrip line. 6 is a point C seen from direction A in FIG. 5 on a plane perpendicular to the longitudinal axis of the conductor 101 through the 0 point in FIG.
It is a partial sectional view of the vicinity. The screw 600 is made of a conductor electrically connected to the strip conductor 400 and is connected to the ground conductor 3.
00 and the dielectric 210 are attached to the notched portion having a circular cross section as shown in the figure. Rotate this screw 600 to move it forward or backward in the X direction, and connect the conductor 101 with the screw 60.
By adjusting the gap between the strip conductor 400 and the tip of the conductor 101, the degree of electromagnetic coupling between the strip conductor 400 and the conductor 101 is adjusted.

A similar coupling screw 601 is also provided below point D in FIG.
The degree of electromagnetic coupling between 00 and conductor 102 can be adjusted. A matching termination (not shown) is connected to one end E of the strip conductor 400. Also, the other end F of the strip conductor 400
A power connection line (not shown) is connected to the power supply line, and this power supply line is connected to a receiver or a transmitter. The distance between the centers of the coupling screws 600 and 601 is selected to be 1/4 of the electrically used wavelength.

・Electromagnetic energy is supplied from the F point side in Figure 5, and 172 of the electromagnetic energy is coupled to the conductor 102 at D point,
If the remaining energy is fully coupled to the conductor 101 at the zero point, left-handed circularly polarized waves can be radiated in the two directions shown in FIG. On the other hand, electromagnetic energy is supplied from the E side of the strip conductor 400, and the coupling screw 600 is adjusted at the 0 point to couple 172 of the electromagnetic energy to the conductor 101, and the remaining energy is coupled to the conductor 102 at the D point. By adjusting the coupling screw 601, right-handed circularly polarized waves can be emitted in two directions.

FIG. 7 is a schematic diagram showing another embodiment of the present invention, in which the dielectrics 200, 210, the ground conductor 300, and the coupling screws 600, 601 shown in FIG. 5 are omitted. This embodiment is an example in which three sets of radiating elements 111 to 113 are arranged in a plane. Each radiating element has a cross shape and consists of 174 wavelength conductors 101 to 104 arranged at 90° intervals like the radiating element in FIG. The coupling between the strip conductor 400 and each radiating element is CI, DI, C2, respectively.
This is done at points D2, C3, and D3. The distance between C1 and Dl, the distance between C2 and D2, and the distance between C3 and D3 are all 174 wavelengths in terms of effective electrical length. In this example,
Electromagnetic energy is supplied from the F side of the power feeding strip conductor 400, and the coupling points C1 to C3 and DI to D3 with the radiating element
The degree of coupling is adjusted so that 176 of the total supplied energy is coupled at each, and one end E of the IJ tube conductor 400 is
If a matching termination (not shown) is provided, it is possible to excite left-handed circularly polarized waves upward in a direction perpendicular to the paper plane of FIG.

Although FIG. 7 shows an example in which three sets of radiating elements are arranged linearly on one plane, they are arranged vertically on one plane.

A circularly polarized antenna can also be obtained by arranging cross-shaped radiating elements in each horizontal direction. In the embodiment shown in FIG. 5, a matching termination is provided to connect to one end E of the strip conductor, but instead of the matching termination, a ground is placed to the left of the 0 point at an effective electrical length of approximately 174 wavelengths. Even if the conductor 300 is provided with means for short-circuiting the strip conductor 400, radiation characteristics similar to those shown in FIG. 5 can be obtained.

(Effects of the Invention) As explained in detail above, the circularly polarized antenna of the present invention can radiate or receive circularly polarized radio waves rotating in any direction by simply changing the feeding point to the strip conductor in the microstrip line. . As described above, according to the present invention, it is possible to provide a circularly polarized antenna in which the direction of rotation of polarized waves can be easily changed.

In order to excite circularly polarized waves, the conventional antenna shown in Figure 1 requires different lengths of the orthogonal conductors of the radiating element, while the conventional conical horn antenna has a complicated configuration to generate circularly polarized waves. However, in the antenna of the present invention, it is only necessary to connect the strip conductors of the microstrip line to two of the four rectangular conductors that form the cross radiating element, which are perpendicular to each other, via coupling screws. . Furthermore, in the conventional antenna shown in Fig. 4, it is necessary to use a hybrid or the like to divide the electromagnetic energy into two equal parts and feed it to the two radiating elements, but in the antenna of the present invention, it is necessary to simply divide the electromagnetic energy into two radiating elements. Should I supply power through a conductor? It is also possible to configure it in a two-dimensional manner, including the power supply line.

Therefore, the present invention has the advantage that the circularly polarized antenna filter structure is simple. Furthermore, since the feeding line is simple as described above, there is an advantage that the loss occurring in the feeding section can be reduced compared to conventional antennas of this type.

[Brief explanation of the drawing]

Figure 1 is a perspective view of a conventional circularly polarized antenna, Figure 2 is a top view of the radiating element of the circularly polarized antenna, and Figure 3 is a circularly polarized wave with the direction of rotation reversed from that in Figure 2. A top view of the radiating element part of the antenna, FIG. 4 is a perspective view of another conventional circularly polarized antenna,
FIG. 5 is a perspective view showing a first embodiment of the invention, FIG. 6 is a partial sectional view of FIG. 5, and FIG. 7 is a schematic diagram showing a second embodiment of the invention. 1.1', 2.2', 101-104...Conductor constituting the radiating element, 3...Outer conductor of coaxial feeder, 4... Center conductor of coaxial feed line, 5.
...Tip of center conductor 4, 6...Outer conductor 3
slits provided in 10.111, 112, 113
・---Radiating element, 20°200.210...
...Dielectric, 40.40', 400...Strip conductor, 30,300...Ground conductor, 600
．． 601...Connecting screws, C, CI, C2°C3, D, DI, D2. D3・Mountain: Connection point between the radiating element and the strip conductor, B, B'・Mountain: Radiating element 10
Feeding point to E, F...Strip conductor 400
end of. Z,? Figure z3 Figure z4 Figure 4ρ Jθ

Claims (1)

[Claims] A microstrip line is formed by fixing a grounding plate and a strip conductor to the first and second wide surfaces of a first dielectric plate, respectively, and a microstrip line is formed by sandwiching the strip conductor between the first dielectric plate and the first dielectric plate. a cross-shaped radiating element fixed to a wide surface of the second dielectric plate with the second dielectric plate sandwiched between the second dielectric plate and the strip conductor; and first and second coupling screws for adjusting the degree of electromagnetic coupling between the radiating element and the radiating element, and the radiating element has an electrical length of approximately 1/4 of the length of the radiated radio wave.
two strip-shaped conductors are arranged in a cross shape, and the first and second coupling screws electromagnetically couple the strip conductors to the two strip-shaped conductors that are orthogonal to each other, and
The interval between the second coupling screws is 4 times the wavelength in terms of electrical length.
A circularly polarized antenna characterized by being 1/2.