JP7325901B2 - Circular Polarized Dual Planar Antenna - Google Patents

Description

Application of Article 30, Paragraph 2 of the Patent Act The 53rd Space Communications Study Group Research Discussion Meeting, July 13, 2018

In the present invention, two circularly polarized signals can be transmitted and received by laminating a circularly polarized wave converter (polarizer) on a linearly polarized planar antenna (antenna section) that emits linearly polarized radio waves that are orthogonal to each other. It relates to a circularly polarized planar antenna.

Satellite communications generally adopt a method of performing communications by changing the frequency and polarization between uplink and downlink. In addition, users on the ground aim for mobile communication, and since the direction of the antenna changes, circularly polarized waves are used to cope with this change. That is, the frequency is changed between transmission and reception, and two circularly polarized waves, a right-handed circularly polarized wave and a left-handed circularly polarized wave, are used.

In order to transmit and receive circularly polarized waves, for example, it is conceivable to arrange a right-handed circularly polarized wave antenna and a left-handed circularly polarized wave antenna side by side. Occupied area becomes larger. Therefore, circularly polarized antennas that can be made smaller and lighter are known (see, for example, Patent Document 1, etc.). This circularly polarized antenna is obtained by superimposing a polarizer section on an orthogonal two linearly polarized antenna obtained by superimposing two microstrip array antennas so that their polarization planes are orthogonal to each other. In the polarizer section, a dielectric sheet whose relative permittivity and thickness are set so as to broadband match the spatial impedance is placed between the polarization lines made of conductors and the dielectric polarization deflection sheet to which the grating is attached. It is inserted.

By the way, in recent years, the frequency is increasing, but it may be difficult for the technology described in Patent Document 1 to cope with the high frequency. That is, in the technique described in Patent Document 1, it is necessary to reduce the width of the polarization line and the like as the frequency increases, but it may be difficult to form the polarization line and the like depending on the height of the frequency. For example, when the frequency is 30 GHz, the minimum width of the polarization line is 0.045 mm (0.0045λ), which makes formation and production difficult.

Therefore, a circularly polarized planar antenna as shown in FIG. 11 has been developed.
This circularly polarized dual planar antenna 60 is an array antenna for transmitting and receiving two circularly polarized signals (right-handed circularly polarized wave and left-handed circularly polarized wave) in microwave band satellite communications. 70, a polarizer section 80 and an upper cover body 90 are laminated.

The antenna unit 70 is an antenna in which an upper feeding element substrate 732 and a lower feeding element substrate 716 are stacked, in which two feeding elements for transmitting and receiving two mutually orthogonal polarized signals are arranged in the same matrix. A first lamination portion 71, a second lamination portion 72, a third lamination portion 73, a fourth lamination portion 74, a fifth lamination portion 75 and a sixth lamination portion 76 are laminated in this order.

The first laminated portion 71 includes a lower cover 711, a base plate 712, a foam sheet (dielectric) 713, a ground plate 714, a foam sheet 715, and a lower feeding element substrate 716, which are stacked in this order from the bottom.

The lower feeding element substrate 716 is a substrate in which feeding elements for receiving polarized signals are arranged in a matrix. It has a rectangular lower layer power supply patch (power supply element) and a lower layer power supply line for supplying power to the lower layer power supply patch.

The second laminated portion 72 has a foam sheet 721 and a lower slot plate 722 laminated in this order from the bottom layer. The lower layer slot plate 722 is provided with a rectangular slot opening at a position facing the lower layer power supply patch.

The third laminated portion 73 has a foam sheet 731 and an upper feeding element substrate 732 laminated in order from the lower layer. The upper feeding element substrate 732 is a substrate in which feeding elements for transmitting polarized signals are arranged in a matrix. It has a plurality of rectangular upper-layer power supply patches (power-supply elements) and an upper-layer power supply line for supplying power to the upper-layer power supply patches.

The fourth laminated portion 74 has a foam sheet 741 and an upper layer slot plate 742 laminated in order from the lower layer. The upper layer slot plate 742 is provided with a rectangular slot opening at a position facing the upper layer power supply patch.

The fifth laminated portion 75 has a foam sheet 751 and a lower parasitic element substrate 752 laminated in this order from the bottom. The lower-layer parasitic element substrate 752 is a substrate in which parasitic elements are arranged in a matrix, and is arranged and arranged in the same manner as the thin lower-layer insulating substrate having insulating properties such as a flexible substrate and the upper-layer power supply patch (power supply element). and a plurality of lower layer parasitic patches (parasitic elements) of conductive foil in a rectangular shape.

The sixth laminated portion 76 has a foam sheet 761 and an upper parasitic element substrate 762 laminated in order from the lower layer. The upper parasitic element substrate 762 is a substrate in which parasitic elements are arranged in a matrix, and is arranged and arranged in the same manner as the thin upper layer insulating substrate having insulating properties such as a flexible substrate and the lower layer feeding patch (feeding element). and a plurality of upper-layer parasitic patches (parasitic elements) of conductive foil in a substantially rhombic shape.

The polarizer section 80 is laminated on the radiation surface side, that is, on the upper side of the antenna section 70, and is composed of meander line polarizers 812, 822, 832, 842, and 852, and converts one of the two polarized signals into left-handed circularly polarized waves. and converts the other into a right-handed circularly polarized wave. In this embodiment, five meander line polarizers 812, 822, 832, 842, 852 are stacked in order from the bottom to obtain a predetermined band, each meander line polarizer 812, 822, 832, 842, 852 Foam sheets 811, 821, 831, 841 and 851 are arranged on the underside of the .

The upper cover body 90 is a laminated body covering the upper side of the polarizer section 80, and includes, in order from the bottom layer, a foam sheet 91, a first inner cover 92, a foam sheet 93, a second inner cover 94, a foam sheet 95 and an upper cover. 96 are stacked.

Since the polarizer unit 80 of the circularly polarized shared planar antenna 60 having such a configuration is composed of the meander line polarizers 812, 822, 832, 842, and 852, it is possible to deal with high frequencies, The line width can be increased compared to the deflection sheet. For example, even if the frequency is 30 GHz, the minimum line width W of the single-layer meander line is about 0.15 mm, and it can be formed and produced by etching.

JP 2004-88185 A

However, in the above circularly polarized planar antenna 60, since the antenna section 70 and the polarizer section 80 are integrated, one polarized wave is converted into a circularly polarized wave in the linearly polarized wave to switch the polarized wave ( However, it was not possible to circularly polarize with a dual-polarized linearly polarized antenna (two-polarized) and switch the polarization.

If it is attempted to switch the polarization, it is necessary to rotate the polarizer by 90°. , and the polarizer unit 80 must be disassembled to switch the polarization.

Therefore, the present invention has a simple structure and can easily switch polarization without disassembly, and a circular polarized wave shared antenna (two polarized waves) that enables circular polarization with a shared polarized wave linearly polarized wave antenna (two polarized waves). An object of the present invention is to provide a planar antenna.

In order to solve the above-mentioned problems, the invention according to claim 1 provides an upper-layer feeder element substrate and a lower-layer feeder element in which two feeder elements for transmitting and receiving two mutually orthogonal polarized wave signals are arranged in the same matrix. and a meander line polarizer which is laminated on the radiation surface side of the antenna section and which converts one of the two polarized signals into a left-handed circularly polarized wave and converts the other into a right-handed circularly polarized wave. a polarizer section for converting into polarized waves, one of the antenna section and the polarizer section having a shaft, the other having a bearing in which the shaft is fitted, and the antenna section and A fixture is provided for fixing the positional relationship between the antenna section and the polarizer section when the polarizer section and the polarizer section are in a predetermined positional relationship.

The invention according to claim 2 is the circularly polarized flat antenna according to claim 1, wherein one end of the shaft and the bearing is fixed to an outer surface side member of the antenna section or the polarizer section, The other end is fixed to an inner surface member of the antenna section or the polarizer section arranged opposite to the outer surface side member.

The invention according to claim 3 is the circularly polarized dual-wave planar antenna according to claim 1 or claim 2, wherein the shaft has a cylindrical portion fitted with the bearing, and the bearing is a concave portion with a circular cross section into which the columnar portion is fitted.

The invention according to claim 4 is the circularly polarized dual-wave planar antenna according to claim 1 or 2, wherein the shaft has a quadrangular prism-shaped portion fitted with the bearing, and the bearing is a recess having a square cross section into which the square columnar portion is fitted.

The invention according to claim 5 is the circularly polarized flat antenna according to any one of claims 1 to 4, wherein the fixture is attached to the antenna section or the polarizer section. the other end to be hooked by a hook provided on the polarizer section or the antenna section; and an elastic section between the one end and the other end. do.

According to the first aspect of the present invention, the central portion of the antenna portion and the polarizer portion in plan view is made rotatable by connecting the shaft and the bearing, so that the polarizer portion is rotated by 90° with respect to the antenna portion. Circularly polarized waves can be switched with just a single operation, and the positioning of the antenna section and the polarizer section in the direction around the axis is performed by the fixture, so that transmission and reception can be performed with high precision.

According to the second aspect of the invention, the thickness of the outer surface side member and the inner surface side member of the antenna part or the polarizer part is adjusted by using the shaft or the bearing at the central part in plan view of the antenna part and the polarizer part. Since the height dimension is regulated, the gap between the slot plates is not changed, and the gap between the feed element substrate and the parasitic element substrate is not changed, so that deterioration of the front gain can be prevented.

According to the third aspect of the invention, the shaft is cylindrical, and the bearing is a recess having a circular cross-section into which the cylindrical shaft is fitted. Circularly polarized waves can be easily switched by rotating the plate.

According to the fourth aspect of the invention, the shaft is formed into a square column shape, and the bearing is formed into a concave portion having a square cross section into which the shaft is fitted. 90°, which enables easy and accurate transmission and reception.

According to the fifth aspect of the invention, since the fixture has an elastic portion, even if the thickness of the foam sheet fluctuates due to expansion, it can be made to follow this.

1 is a plan view of a circularly polarized planar antenna according to Embodiment 1 of the present invention; FIG. 1 is a rear view of the circularly polarized planar antenna according to Embodiment 1 of the present invention; FIG. FIG. 2 is a cross-sectional view taken along line III-III in FIG. 1, showing a state in which the antenna section and the polarizer section are separated from each other. (a) is a plan view of the portion where the shaft of the polarizer unit is attached, and (b) is (b)-(b) in FIGS. (a) and (c). is a cross-sectional view taken along , and (c) is a bottom view of the portion where the bearing of the antenna section is attached. FIG. 2 is an enlarged cross-sectional view taken along line VV in FIG. 1; FIG. 3 is an exploded perspective view showing the antenna section with its front side opened downward and the polarizer section with its front side opened upward. It is a perspective view which expands and shows a fixture. It shows a state in which a transceiver, a tripod, etc. are attached to a circularly polarized flat antenna, (a) is a front view, (b) is a side view, and (c) is a rear view. FIG. 4A is a front view sequentially showing how circularly polarized waves of the circularly polarized dual plane antenna are switched; (c) shows a state in which the polarizer section is rotated by 90° from the state in (a) shown. FIG. 4 is an enlarged perspective view of a main portion showing Embodiment 2 of the present invention; FIG. 2 is an exploded perspective view showing a laminated structure of a conventional circularly polarized planar antenna;

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below based on the illustrated embodiments.

1 to 9 show Embodiment 1 of the present invention. FIG. 1 is a plan view of a circularly polarized shared planar antenna 1, and FIG. 2 is a bottom view of the circularly polarized shared planar antenna 1. FIG. This circularly polarized dual planar antenna 1 is an array antenna for transmitting and receiving two circularly polarized signals (right-handed circularly polarized wave and left-handed circularly polarized wave) in satellite communication in the microwave band. 2. A radome 3, a polarizer section 4 and an upper cover body 5 are laminated.

Since the laminated structure of the circularly-polarized planar antenna 1 is substantially the same as that of the circularly-polarized planar antenna 60 shown in the conventional example, details thereof will be omitted.

The antenna unit 2 is an antenna in which two feeding elements for transmitting and receiving two mutually orthogonal polarized signals are arranged in the same matrix, and an upper feeding element substrate and a lower feeding element substrate are laminated, and has a square dish shape. A foam sheet 22, a base plate 23, and a plurality of sets of A combination layer of the foam sheet 25 and the slot plate 24 (six layers in the example shown in FIG. 4(b)) and the foam sheet 32 on the radome 3 side are laminated (the foam sheet 32 on the radome 3 side and the radome on the radome 3 side). A radome plate may be disposed between the cover 31). In addition, in FIG. 4(b), the reference numerals 24 and 25 are only partly indicated and the others are omitted.

The foam sheet 22 is provided to fill the gap between the lower cover 21 and the base plate 23, and the foam sheet 25 serves as a dielectric to ensure the vertical distance (such as the gap between the slot plates 24 and 24). is provided to do so. The base plate 23 and slot plate 24 are made of, for example, an aluminum plate, the lower cover 21 is made of, for example, ASA resin, and the radome upper cover 31 is made of, for example, vinyl chloride. The materials of the lower cover 21, the base plate 23, the slot plate 24, and the radome upper cover 31 are not limited to these.

The radome 3 is interposed between the antenna section 2 and the polarizer section 4 to make the antenna section 2 and the polarizer section 4 independent. The antenna section 2 includes, as the radome 3 , a radome upper cover 31 forming the upper surface of the antenna section 2 and a foam sheet 32 on the radiation surface side, ie, the upper side. In addition, the polarizer section 4 includes a radome lower cover 33 and a foam sheet 34 forming the lower surface of the polarizer section 4 on the lower side as the radome 3 .

The radome upper cover 31 is formed with a shallow circular concave portion 31a opening upward at the central portion of the antenna portion 2 in plan view, and a substantially rectangular opening is formed in the central portion of the lower cover 21 in plan view. , are rectangular recesses. Two antenna ports 18 are provided in this rectangular recess. The two antenna ports 18 are shown only in FIG. 2, and the antenna ports are omitted in FIGS. 3 and 4. FIG.

A bearing 6 is attached to the bottom surface of the circular recess 31 a of the radome upper cover 31 .

The bearing 6 has a bottomed and slightly thick tubular body 6a and a flange portion 6b provided at the bottom of the tubular body 6a. ) is inserted to act as a thrust bearing.

An opening is formed in the bottom surface of the circular concave portion 31a of the radome upper cover 31, and a screw groove 6c is formed in the outer peripheral surface of the cylindrical body 6a of the bearing 6. A hexagonal nut 7 is inserted into the opening of the recessed portion 31a from below, and a hexagonal nut 7 is screwed into the screw groove 6c projecting into the circular recessed portion 31a, so that the peripheral edge of the opening of the bottom surface of the circular recessed portion 31a is connected to the flange portion 6b and the hexagonal nut. 7 and fixed to the radome upper cover 31 as a radome side member/inner surface side member.

The fixing of the bearing 6 to the antenna part 2 is carried out by mounting the flange part 6b on four cell spaces 8 that are press-fitted upward to the base plate 23 and fixing the bearing 6 to the antenna part 2 from above through screw holes formed in the flange part 6b. This is done by screwing four mounting screws 9 into each cell space 8 . The base plate 23 is integrated with the lower cover 21 as an outer surface side member at a plurality of locations by means of cell spacers and screws. The portion exposed through the central opening functions as part of the outer surface side member.

As a result, the distance between the base plate 23 as the outer surface side member which is the metal plate on the lower side of the antenna section 2 and the radome upper cover 31 as the radome side member/inner surface side member is regulated by mounting the bearing 6, Even if the foam sheets 25 and 32 sandwiched between them tend to expand due to environmental changes such as temperature and humidity, this can be suppressed.

When the foam sheets 25, 32 and the like expand, the spacing between the slot plates 24 in the stacking direction changes. Suppressing the expansion of 32 prevents deterioration of the front gain.

In addition, the lower cover 21 and the radome upper cover 31 are each formed with folded portions 21a and 31b that are once bent outward and further bent so as to curl. A rubber packing 13 having a C-shaped longitudinal section is provided so as to wrap the two folded portions 21a and 31b together with their peripheral edges overlapping each other. The rubber packing 13 is made of a relatively hard rubber material, so that the lower cover 21 and the radome upper cover 31 are firmly adhered to each other even at the peripheral edges thereof, and are waterproof and dustproof.

In this way, since the peripheral portions of the lower cover 21 and the radome upper cover 31 are also positioned in the stacking direction, the antenna portion 2 can be positioned not only at the central portion in plan view but also at the peripheral portions. 32 expansion can be suppressed.

As shown in FIG. 3, the polarizer section 4 is laminated on the radiation surface side, that is, on the upper side of the antenna section 2, and is composed of a combination of a plurality of sets of meander line polarizers 41 and foam sheets 42, and has two polarizers. One of the wave signals is converted to left-handed circularly polarized waves and the other is converted to right-handed circularly polarized waves.

The polarizer section 4 also includes, in substantially the same manner as the antenna section 2, an upper cover 51 having a square dish shape as an outer surface side member and a radome side member having substantially the same shape as the upper cover 51 and a radome lower portion as an inner surface side member. Between the cover 33, a foam sheet 52, a combination of multiple sets of meander line polarizers 41 and foam sheets 42 (four layers in the example shown in FIG. 4B), and a foam sheet 34 on the radome 3 side etc. are laminated (a radome plate may be arranged between the foam sheet 34 on the radome 3 side and the radome lower cover 33 in some cases).

A shaft mounting hole penetrating vertically is formed in the central portion of the polarizer portion 4 in a plan view. Further, the radome lower cover 33 is formed with a shallow circular concave portion 33a opening downward. The lower end of the shaft mounting hole opens to the bottom surface (positionally top surface) of the circular recess 33a. A shaft 10 is attached to such a shaft attachment hole.

The shaft 10 is fitted in the bearing 6 described above to allow the antenna section 2 and the polarizer section 4 to rotate in the direction around the shaft.

Specifically, the shaft 10 includes a body portion 10a fitted into the shaft mounting hole, a flange portion 10b provided at one end of the body portion 10a, and a flange portion 10b provided at the other end, which is slightly larger than the body portion 10a. and a thin shaft portion 10c. The length of the shaft 10 is adjusted so that the shaft portion 10 c protrudes from the lower surface of the radome lower cover 33 while the flange portion 10 b is in contact with the bottom surface of the upper cover 51 . The shaft diameter of the shaft portion 10c is slightly smaller than the diameter of the recess 6d of the bearing 6. As shown in FIG. Further, a thread groove 10d is formed on the outer peripheral surface of a portion of the body portion 10a on the shaft portion 10c side and protruding into the circular recess 33a of the radome lower cover 33. As shown in FIG.

Then, such shaft 10 is inserted from above the shaft mounting hole of the polarizer portion 4, and the upper cover 51 is placed in this state, and the flange portion 10b is in contact with the bottom surface of the upper cover 51. It is fixed to the upper cover 51 by three mounting screws 12 .

Furthermore, by screwing a hexagonal nut 11 into the screw groove 10d projecting into the circular recess 33a of the radome lower cover 33, the peripheral edge of the opening of the bottom surface (top surface) of the circular recess 33a is held by the hexagonal nut 11. , the shaft 10 is fixed to the central portion of the polarizer section 4 . As a result, the distance between the upper cover 51 and the radome lower cover 33 is regulated, and even if the foam sheets 42, 52 sandwiched between them tend to expand due to environmental changes such as temperature and humidity, this can be suppressed. .

In the circularly polarized flat antenna 1 configured as described above, the lower antenna section 2 and the radome 3 (radome upper cover 31, foam sheet 32) on the side of the antenna section 2 are waterproof and dustproof as a whole. Moreover, the upper cover body 5, the polarizer section 4, and the radome 3 (the radome lower cover 33, the foam sheet 34) on the side of the polarizer section 4 are subjected to waterproof and dustproof treatment as a whole. Thus, the circularly polarized shared planar antenna 1 is protected from rainwater and dust.

Next, the connection between the antenna section 2 and the polarizer section 4 will be described.

First, as described above, by fitting the shaft 10 of the polarizer section 4 into the bearing 6 of the antenna section 2, the connection between the two is completed, and the circularly polarized dual-wave planar antenna 1 is completed.

As described above, the antenna section 2 and the polarizer section 4 are rotatable in the axial direction due to the relationship between the shaft 10 and the bearing 6, and by rotating them by 90°, the circular polarization can be switched. can be done.

In order to prevent the antenna section 2 and the polarizer section 4 from rotating, fixtures 15 provided at the four corners of the circularly polarized flat antenna 1 are used.

The fixture 15 has a slightly oblong rectangular elastic portion, one end of which is attached to the mounting portion 16 of the polarizer portion 4 and the other end of which is provided with a ring 17 . The fixing member 15 may be configured as a rubber band with an elastic portion made of a rubber material. Such fixtures 15 are attached to band attachment portions 16 provided at respective side edges near the left and right ends (four corners) of two opposing sides among the four sides of the polarizer portion 4 . The fixtures 15 may be provided only at two diagonal positions in a plan view of the polarizer section 4 .

Hooking metal fittings 14 for hooking rings 17 of fixtures 15 are provided at four locations near the four corners on the bottom surface of the antenna section 2 . The hook 14 has a flat screw shape that is thin in the axial direction, and its head is formed to have a size through which the ring 17 of the fixture 15 can pass.

The fastening of the antenna section 2 and the polarizer section 4 by the fixture 15 is performed by pulling the fixture 15 downward from the side edge of the polarizer section 4 and bending it along the bottom surface of the antenna section 2 to attach the ring 17 to the hook fitting 14 . It is done by hooking.

At this time, even when the polarizer section 4 is rotated by 90° with respect to the antenna section 2 as will be described later, since the hooks 14 are formed at the four corners of the antenna section 2, the length from any side edge is the same. and can be fastened with the same tension.

In addition, by fastening the antenna part 2 and the polarizer part 4 in the stacking direction with the fixture 15 having an elastic part, the aggregate of the foam sheets fluctuates in the thickness direction of the other, but it follows this. be able to.

Next, an example of use of the circularly polarized planar antenna 1 configured as described above will be described.

First, in such a circularly polarized dual-wave planar antenna 1, a box-shaped transmitter/receiver 20 is attached to the back side of the antenna portion 2, and the transmitter/receiver 20 is attached to a tripod 40 via a mounting base 30 (see FIG. 1). 8).

The circularly polarized shared planar antenna 1 attached to the tripod 40 is used with the four corners of the planar square positioned vertically and horizontally, and at an angle of about 45° as a whole.

When switching the circularly polarized wave, the ring 17 of the fixture 15 is removed from the hook 14 of the antenna section 2 in the state shown in FIG. 9(a). The state of FIG. 9A is, for example, a state in which left-handed circularly polarized waves are used for transmission and right-handed circularly polarized waves are received.

When the ring 17 of the fixture 15 is removed from the hook 14 , the polarizer section 4 becomes rotatable with respect to the antenna section 2 .

Next, the polarizer section 4 is rotated clockwise. FIG. 9(b) shows a state rotated by 45°.

Further, when the polarizer unit 4 is rotated clockwise by 45° to obtain the state shown in FIG. 9C, the state is switched to transmit right-handed circularly polarized waves and receive left-handed circularly polarized waves.

In this state, the ring 17 of the fixture 15 is hooked on the hook 14 of the antenna section 2 to prevent rotation.

As described above, according to the circularly polarized planar antenna 1 of this embodiment, the polarizer section 4 can be easily rotated and the circularly polarized waves can be switched simply by attaching and detaching the fixture 15 .

As a method for distinguishing whether the current positional relationship between the antenna section 2 and the polarizer section 4 is left-handed circularly polarized waves or right-handed circularly polarized waves, it is conceivable to provide an identifier on the surface of the polarizer section 4, for example.

For example, two corners of the upper cover 51 of the polarizer section 4 are provided with different identifiers (marked with a circle, a mark of a cross) A, while the front corner of the lower antenna section 2 is provided with an identifier B. (parts painted black in the figure) are provided. As a result, when identifier B corresponds to identifier A "o", it is a left-handed circularly polarized wave, and when it corresponds to identifier A "x", it can be easily determined that it is right-handed circularly polarized wave.

If the polarizer section 4 is removed from the antenna section 2, the antenna section 2 alone can be used as a planar antenna for linearly polarized waves.

Next, a circularly polarized planar antenna according to Embodiment 2 of the present invention will be described. FIG. 10 is an enlarged perspective view illustrating the essential parts (shaft and bearing) of Embodiment 2. FIG.

The shaft portion 10Ac of the shaft 10A of the polarizer portion 4 according to the second embodiment is formed into a quadrangular prism, and the concave portion 6Ad of the bearing 6A of the antenna portion 2 is formed into a quadrangular cross section.

Although the shaft 10A and the bearing 6A cannot be rotated, the polarizer section 4 is once removed from the antenna section 2, and then rotated 90° with the polarizer section 4 removed. 2, circularly polarized waves can be switched.

Although the embodiments of the present invention have been described above, the specific configuration is not limited to the above-described embodiments. Included in the invention. For example, in the above embodiment, the shaft 10 is provided in the polarizer section 4 and the bearing 6 is provided in the antenna section 2. may be provided in the antenna section 2.

1 circularly polarized flat antenna 2 antenna section 3 radome 4 polarizer section 21 lower cover (outer surface side member)
24 slot plate 31 radome upper cover (radome side member/inner surface side member)
33 Radome lower cover (radome side member/inner surface side member)
51 upper cover (outer surface side member)
6 bearing 7 hexagonal nut (fastener)
10 shaft 11 hexagonal nut (fastener)
14 hook fitting (hook fitting)
15 fixture 6A bearing 10A shaft

Claims (5)

an antenna section in which an upper-layer feeding element substrate and a lower-layer feeding element substrate are laminated, in which two feeding elements for transmitting and receiving two mutually orthogonal polarized wave signals are respectively arranged in the same matrix form;
a polarizer unit that is laminated on the radiation surface side of the antenna unit, is composed of a meander line polarizer, and converts one of the two polarized signals into a left-handed circularly polarized wave and the other into a right-handed circularly polarized wave; have
One of the antenna section and the polarizer section has a shaft, and the other has a bearing in which the shaft is fitted,
A fixture that fixes the positional relationship between the antenna section and the polarizer section when the antenna section and the polarizer section are in a predetermined positional relationship,
A circularly polarized planar antenna characterized by: One end of the shaft and the bearing is fixed to the outer surface side member of the antenna section or the polarizer section, and the other end is an inner surface side member arranged to face the outer surface side member of the antenna section or the polarizer section. fixed to
2. The circularly polarized planar antenna according to claim 1, wherein: The shaft has a cylindrical portion that fits into the bearing, and the bearing is a concave portion with a circular cross section into which the cylindrical portion fits.
3. The circularly polarized planar antenna according to claim 1, wherein: The shaft has a quadrangular prism-shaped portion that fits with the bearing, and the bearing is a recess with a quadrangular cross section into which the quadrangular prism-shaped portion fits.
3. The circularly polarized planar antenna according to claim 1, wherein: The fixture includes one end attached to the antenna section or the polarizer section, the other end hooked to a hook provided on the polarizer section or the antenna section, the one end and the other end. and an elastic portion between the
5. The planar antenna for circularly polarized waves according to any one of claims 1 to 4, characterized in that:

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