JP2010220047A - Antenna device and array antenna device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an antenna device and an array antenna device, reducing an antenna size, carrying out thinning, and also reducing a weight. <P>SOLUTION: Provided are a metal cavity 1 with a shallow bottom provided with a square bottom face and a square opening surface, four excitation probes 2, an excitation patch conductor 3 in the shape of a square plate, and a non-excitation conductor 4 in the shape of a square plate. The four excitation probes 2 are arranged in positions which serve as a rotational symmetry every right angle to a center of a radiation conductor in the circumferential direction, and the radiation conductor is excited by an electromagnetic coupling by giving a right angle phase difference between the adjacent probes. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an antenna device and an array antenna device which constitute a patch antenna mounted on an artificial satellite and used for satellite communication or the like, for example.

  In general, when an antenna is mounted on an artificial satellite, the space for the rocket and the weight when the rocket is launched are limited. Therefore, the antenna needs to be structurally small and lightweight.

  An example of a conventional satellite-mounted antenna is, for example, a horn antenna (see, for example, Patent Document 1). A conventional horn antenna that radiates circularly polarized waves will be described with reference to FIG. FIG. 6 is a diagram showing a configuration of a conventional horn antenna that radiates circularly polarized waves. FIG. 6A is a plan view seen from above, and FIG. 6B is a cross-sectional view taken along line AA ′ shown in FIG.

In FIG. 6, the horn antenna 20 is provided with a waveguide 21, four probes 22, and a tapered horn antenna opening 23. The four probes 22 are arranged so as to be shifted by 90 degrees in the circumferential direction in order to excite circularly polarized waves.
Is.

  Next, the operation of a conventional horn antenna that radiates circularly polarized waves will be described with reference to the drawings.

  A probe 22 is connected via a side wall of the waveguide 21 from a circularly polarized wave excitation circuit provided outside the waveguide 21. The probe 22 is located at a location approximately λg / 4 wavelength (λg: wavelength in the tube) away from the bottom surface of the short-circuited waveguide 21, so that the waveguide 21 is efficiently excited. The four probes 22 have different excitation phases by 90 degrees adjacent to each other, and good circular polarization excitation is realized. A tapered horn antenna opening 23 is connected to the side opposite to the short-circuited surface of the excited waveguide 21, and circularly polarized radiation is gradually produced while matching the space.

JP-A-4-35507

  However, the prior art has the following problems. In the conventional horn antenna as described above, the excitation probe 22 is arranged at a position approximately λg / 4 wavelength away from the short-circuited surface of the waveguide 21, and the waveguide is so formed as to excite the waveguide mode ahead. Is further extended, and a tapered horn antenna opening 23 is connected to the tip. For this reason, there were problems in terms of antenna size (full length and opening diameter) and weight. In addition, since the excitation probe 22 is connected to the circularly polarized wave excitation circuit through the side wall of the waveguide 21, the circularly polarized wave excitation circuit is used when configuring an array antenna device in which a plurality of antenna elements are arranged. It was difficult to secure a layout space to be arranged.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an antenna device that can be reduced in size and thickness and can be reduced in weight. To do. It is another object of the present invention to provide an array antenna apparatus that can secure a layout space for a circularly polarized wave excitation circuit when arranging a plurality of antenna elements.

  The antenna device according to the present invention is such that a top surface of a cylinder having a bottom surface with a predetermined shape is open to a space, has an opening surface with a predetermined shape, a side wall from the bottom surface to the opening surface has a predetermined height, A first radiation conductor in the form of a plate opposed to the cavity at a predetermined interval from the bottom surface of the cavity, and having a size different from the size of the first radiation conductor, Between the plate-like second radiation conductor disposed opposite to the radiation conductor at a predetermined interval, and between the bottom surface of the cavity and the first radiation conductor, both the bottom surface of the cavity and the first radiation conductor Are inserted at a predetermined interval from each other, a tip portion is electrically connected to the first radiation conductor by electromagnetic coupling, and the other end portion is connected to a circularly polarized wave excitation circuit via a side wall of the cavity. The excitation probe and the front 90 degree rotational symmetry to one circumferential direction of the bottom surface of the cavity with respect to the first excitation probe, having the same configuration as the first excitation probe, with the center of the bottom surface of the cavity as a reference point A second excitation probe having an excitation phase different by 90 degrees with respect to the excitation phase of the first excitation probe, the same configuration as the first excitation probe, and the bottom surface of the cavity The first excitation probe is arranged so as to be 180 degrees rotationally symmetric with respect to the first excitation probe in the circumferential direction of the cavity, and the excitation phase is the first excitation probe. The first excitation probe has the same configuration as the first excitation probe and a third excitation probe that is 180 degrees different from the excitation phase of the probe, and the center of the bottom surface of the cavity is the reference point. A fourth excitation probe which is arranged so as to be rotationally symmetrical with respect to the lobe to one side in the circumferential direction of the bottom surface of the cavity and whose excitation phase is 270 degrees different from the excitation phase of the first excitation probe. Are provided.

  According to the antenna device of the present invention, the antenna size can be reduced in size and thickness, and the weight can be reduced.

It is a figure which shows the structure of the antenna apparatus which concerns on Embodiment 1 of this invention. It is sectional drawing which shows the structure of the antenna apparatus which concerns on Embodiment 2 of this invention. It is sectional drawing which shows the structure of the antenna apparatus which concerns on Embodiment 3 of this invention. It is a figure which shows the electrical property of the antenna apparatus which concerns on Embodiment 1-3 of this invention. It is a top view which shows the structure of the array antenna apparatus which concerns on Embodiment 4 of this invention. It is a figure which shows the structure of the horn antenna which radiates | emits the conventional circularly polarized wave.

  Hereinafter, preferred embodiments of an antenna device of the present invention will be described with reference to the drawings. In each embodiment, as an ideal configuration of an antenna device, a configuration in which each conductor and a dielectric substrate between lines is omitted will be described.

Embodiment 1 FIG.
An antenna apparatus according to Embodiment 1 of the present invention will be described with reference to FIG. FIG. 1 is a diagram showing a configuration of an antenna apparatus according to Embodiment 1 of the present invention. FIG. 1A is a plan view seen from above, and FIG. 1B is a cross-sectional view taken along line AA ′ shown in FIG. In addition, in each figure, the same code | symbol shows the same or equivalent part.

  1, an antenna device 10 according to Embodiment 1 of the present invention includes a metal cavity 1 having a square bottom surface and an opening surface, four excitation probes 2, and a square plate-like (planar) excitation patch. A conductor (first radiating conductor) 3 and a square plate-like (planar) non-excited conductor (second radiating conductor) 4 are provided.

  The metal cavity 1 is not restricted by the shape of the opening surface. There are a total of four excitation probes 2, which are arranged at positions that are 90-degree rotationally symmetric between adjacent probes in the circumferential direction of the excitation patch conductor 3 with respect to the center of the excitation patch conductor 3. The excitation patch conductor 3 and the non-excitation conductor 4 are not limited by the shape. Further, the excitation patch conductor 3 is disposed opposite to the bottom surface of the cavity 1 and the non-excitation conductor 4 is disposed opposite to the excitation patch conductor 3.

  The tip of the excitation probe 2 that is a strip line is disposed in the space between the bottom surface of the cavity 1 and the excitation patch conductor 3. The other end of the excitation probe 2 extends in the space between the bottom surface of the cavity 1 and the excitation patch conductor 3 in the direction of the side wall of the cavity 1 and is circularly polarized via the side wall (side surface) of the cavity 1. It is electrically connected to the excitation circuit.

  The size of the excitation patch conductor 3 is set in advance to a size corresponding to a desired low-frequency resonance frequency (reference resonance frequency). In addition, the size of the non-excited conductor 4 that is disposed opposite to the excitation patch conductor 3 with a space therebetween is set in advance to a size corresponding to a desired high-frequency resonance frequency.

  Here, a proximity coupling power feeding method, which is a kind of electromagnetic coupling, is used as an excitation method for the excitation patch conductor 3. That is, the excitation patch conductor 3 and the excitation probe 2 are electrically connected by electromagnetic coupling. On the other hand, the non-excited conductor 4 is electrically connected by electromagnetic coupling like the excited patch conductor 3.

  Further, the antenna device 10 according to the first embodiment has the resonance points of the low-frequency resonance frequency caused by the size of the excitation patch conductor 3 and the high-frequency resonance frequency caused by the size of the non-excitation conductor 4. Resonance is possible. That is, the excitation patch conductor 3 resonates when an input signal having a low resonance frequency is received from the circularly polarized wave excitation circuit via the excitation probe 2, and the non-excited conductor 4 is excited from the circularly polarized wave excitation circuit. 2 and the excitation patch conductor 3, it resonates and emits radio waves when it receives an input signal having a high-frequency resonance frequency. Therefore, the electrical characteristics of the antenna device 10 according to the first embodiment are two resonance characteristics.

  Next, the operation of the antenna device according to the first embodiment will be described with reference to the drawings.

  Here, a case where the antenna apparatus 10 of the first embodiment is used for transmission will be described, but it can also be used for reception. The low-band resonance frequency input signal from the circularly polarized wave excitation circuit is transmitted to the excitation patch conductor 3 by electromagnetic coupling via the excitation probe 2. The excitation probe 2 is disposed 90 degrees rotationally symmetric with respect to the center of the excitation patch conductor 3. Each excitation probe 2 receives an excitation signal having a phase difference of 90 degrees by a circularly polarized wave excitation circuit. Thereby, circularly polarized waves are radiated from the excitation patch conductor 3.

  On the other hand, an input signal having a high-frequency resonance frequency is transmitted from the circularly polarized wave excitation circuit to the non-excited conductor 4 by electromagnetic coupling through the excitation probe 2 and the excitation patch conductor 3, and is radiated therefrom. As in the case of the above low-frequency resonance frequency, excitation signals having a phase difference of 90 degrees are input to each excitation probe 2 by the circularly polarized wave excitation circuit even at the high-frequency resonance frequency. Circularly polarized light is radiated from the excitation conductor 4.

  In the antenna device 10 according to the first embodiment, since circularly polarized waves are radiated from the excitation patch conductor 3 or the non-excitation conductor 4 by the four-point excitation by the excitation probe 2, the axial ratio characteristic can be lowered. That is, the antenna device 10 according to the first embodiment can have the electrical characteristics of the two resonance characteristics and the low axial ratio characteristics.

  By the way, the antenna device 10 of the first embodiment has a metal cavity 1 having a rectangular cross section. By adjusting the height of the cavity 1, the radiation pattern shape and gain can be adjusted.

  Specifically, when the height of the cavity 1 is set to be relatively low, the beam width can be increased and the coverage area can be expanded. On the other hand, when the height of the cavity 1 is set relatively high, the beam width can be reduced, and the gain of the main beam can be increased. The height of the cavity 1 is radiated from the excitation patch conductor 3 or the non-excitation conductor 4 and propagates in the cavity 1 due to the in-tube wavelength (the shape of the excitation patch conductor 3, the shape, size, etc. of the cavity 1). When it is set to be an integral multiple of a quarter wavelength, the gain in the zenith direction (above FIG. 1B) can be maximized.

  Moreover, although it is the magnitude | size of the opening surface of the cavity 1, an antenna characteristic will converge if it is a certain size or more. When the element (antenna device 10) is not used alone but in an array state, the size of the opening surface of the cavity 1 is less than one wavelength so that desired characteristics (gain, beam width, etc.) are obtained. It can be set arbitrarily to some extent.

  In FIG. 1, the cavity 1 is entirely surrounded by a metal conductor in the cavity 1, but even when at least a part of the sidewall is surrounded by a conductor, the antenna characteristics may not be affected. Therefore, a slit may be provided on the side wall of the cavity 1 to satisfy this, and there is no problem even if the side wall itself is constituted by a metal mesh or the like. That is, a part of the side wall of the cavity 1 may be a discontinuous metal conductor.

  According to the antenna device 10 according to the first embodiment, since the radiation conductor is excited by electromagnetic coupling using the excitation probe 2, the cavity 1 having a shallow bottom is not required as in the case of the waveguide. Thus, the side wall of the cavity 1 does not increase, and the entire antenna can be reduced in size (thinned). In addition, since the four excitation probes 2 are arranged so as to be rotationally symmetric every 90 degrees in the circumferential direction with respect to the center of the opening surface of the cavity 1 and an excitation phase difference is provided every 90 degrees, Has axial ratio characteristics. Furthermore, the non-excited conductor 4 is also loaded, so that a wide band can be achieved by two resonance characteristics. Needless to say, in the case of an application that does not have two resonance characteristics or broadband characteristics, a structure in which the non-excited conductor 4 is not loaded may be used.

Embodiment 2. FIG.
An antenna device according to Embodiment 2 of the present invention will be described with reference to FIG. FIG. 2 is a cross-sectional view showing the configuration of the antenna device according to Embodiment 2 of the present invention. FIG. 2 is a cross-sectional view similar to FIG.

  2, an antenna device 10A according to Embodiment 2 of the present invention includes a metal cavity 1 having a square bottom surface and an opening surface, four L-shaped excitation probes 2A, and a square plate shape (planar shape). Excitation patch conductor (first radiating conductor) 3 and a square plate (planar) non-exciting conductor (second radiating conductor) 4 are provided.

  A part of the description overlapping with the first embodiment will be omitted. The L-shaped excitation probe 2A is configured by connecting an inner conductor 2a of a coaxial line and a strip-shaped microstrip line 2b (details will be described later). There are a total of four L-shaped excitation probes 2 </ b> A, which are arranged at positions that are 90-degree rotationally symmetric between adjacent probes in the circumferential direction of the excitation patch conductor 3 with respect to the center of the excitation patch conductor 3.

  The tip of the microstrip line 2 b is disposed in the space between the bottom surface of the cavity 1 and the excitation patch conductor 3. The other end of the microstrip line 2 b extends in the space between the bottom surface of the cavity 1 and the excitation patch conductor 3 in the direction of the side wall of the cavity 1 and is not in contact with the side wall of the cavity 1. On the other hand, the bottom side tip of the cavity 1 of the coaxial line 2 a is connected to a circularly polarized wave excitation circuit (not shown) provided outside the bottom surface of the cavity 1 through a hole 5 provided in the bottom surface of the cavity 1. It is connected. The other end of the coaxial line 2a extends vertically upward toward the opening surface of the cavity 1 and is connected to the other end of the microstrip line 2b. Thereby, L-shaped excitation probe 2A is comprised. In other words, the L-shaped excitation probe 2 </ b> A is electrically connected to the excitation patch conductor 3 by electromagnetic coupling and has the other end connected to the circularly polarized wave excitation circuit via the bottom surface of the cavity 1.

  Next, the operation of the antenna device according to the second embodiment will be described with reference to the drawings.

  The low-band resonance frequency input signal from the circularly polarized wave excitation circuit is transmitted to the excitation patch conductor 3 by electromagnetic coupling via the L-shaped excitation probe 2A. The L-shaped excitation probe 2 </ b> A is disposed 90 degrees rotationally symmetrical with respect to the center of the excitation patch conductor 3. Each L-shaped excitation probe 2A receives an excitation signal having a phase difference of 90 degrees by a circularly polarized wave excitation circuit. Thereby, circularly polarized waves are radiated from the excitation patch conductor 3. On the other hand, an input signal having a high-band resonance frequency is transmitted from the circularly polarized wave excitation circuit to the non-excited conductor 4 by electromagnetic coupling via the L-shaped excitation probe 2A and the excitation patch conductor 3, and is emitted therefrom. As in the case of the above-described low-frequency resonance frequency, excitation signals having a phase difference of 90 degrees are input to each L-shaped excitation probe 2A by the circularly polarized wave excitation circuit even at the high-frequency resonance frequency. Therefore, circularly polarized waves are radiated from the non-excited conductor 4.

  In the antenna device 10A of the second embodiment, if the coaxial line 2a and the microstrip line 2b constituting the L-shaped excitation probe 2A can be integrally formed, there is no connection between different metals, and passive intermodulation occurs. Can be prevented. Note that this passive intermodulation is a phenomenon in which distorted radio waves and cross modulation occur when a large amount of power is input to locations connected by different metals.

  In addition, good antenna characteristics in a desired frequency band when the total length from the bottom side tip of the cavity 1 of the L-shaped excitation probe 2A to the tip of the microstrip line 2b is approximately ¼ wavelength in electrical length. (In particular, impedance characteristics and reflection characteristics) can be obtained.

  Although the cavity 1 is entirely surrounded by the metal conductor, the cavity 1 may not affect the antenna characteristics even when at least a part of the sidewall is surrounded by the conductor. Therefore, a slit may be provided on the side wall of the cavity 1 to satisfy this, and there is no problem even if the side wall itself is constituted by a metal mesh or the like. That is, a part of the side wall of the cavity 1 may be a discontinuous metal conductor.

  According to the antenna device 10A of the second embodiment, in addition to the effects of the first embodiment, the L-shaped excitation probe 2A is connected to the circularly polarized wave excitation circuit via the bottom surface of the cavity 1. When configuring the array antenna device, the layout space of the circularly polarized wave excitation circuit can be secured.

Embodiment 3 FIG.
An antenna device according to Embodiment 3 of the present invention will be described with reference to FIGS. FIG. 3 is a cross-sectional view showing the configuration of the antenna device according to Embodiment 3 of the present invention. FIG. 3 is a cross-sectional view similar to FIG.

  In FIG. 3, an antenna device 10B according to Embodiment 3 of the present invention includes a metal cavity 1 having a square bottom surface and an opening surface, four L-shaped excitation probes 2A, and a square plate shape (planar shape). Exciting patch conductor 3, a square plate-like (planar) non-exciting conductor 4, a dielectric substrate 6, and a microstrip line 7 are provided.

  In the description of the antenna device 10A according to the second embodiment, it has been mentioned only that the circularly polarized wave excitation circuit is configured on the back side of the bottom surface of the cavity 1. A wave excitation circuit is constituted by a microstrip line 7 on a dielectric substrate 6 and is affixed to the back surface of the bottom surface of the cavity 1.

  In FIG. 3, most of the surface of the dielectric substrate 6 on the cavity 1 side is covered with copper foil (functions as a ground surface), and a circularly polarized wave excitation circuit is formed on the back surface of the dielectric substrate 6. Yes. The microstrip line 2b constituting the L-shaped excitation probe 2A is connected to the inner conductor 2a of the coaxial line, and the circularly polarized wave excitation circuit is constituted by the same microstrip line 7 at the tip of the inner conductor 2a.

  The structure in the vicinity where the inner conductor 2a of the coaxial line and the microstrip line 7 are connected will be described in more detail. The back surface of the bottom surface of the cavity 1 and the surface of the dielectric substrate 6 (mostly covered with copper foil) are bonded together so as to be electrically connected. A hole 5 is formed in the bottom surface of the cavity 1 so as to avoid contact with the inner conductor 2a of the coaxial line, and a hole that avoids contact with the copper foil on the surface of the dielectric substrate 6 at the same position is etched. Open at. Also, a hole through which the inner conductor 2a of the coaxial line passes is opened in the dielectric substrate 6 at the same position. That is, the inner conductor 2 a of the coaxial line can extend to the back surface of the dielectric substrate 6 without contact between the cavity 1 and the ground surface on the surface of the dielectric substrate 6. A microstrip line 7 having a hole through which the inner conductor 2a of the coaxial line penetrates is formed on the back surface of the dielectric substrate 6 by etching or the like. After the inner conductor 2a of the coaxial line has penetrated, soldering or the like is performed. Both are connected. Thereby, the L-shaped excitation probe 2A and the circularly polarized wave excitation circuit are connected.

  Therefore, since the circularly polarized wave excitation circuit configured on the dielectric substrate 6 is installed on the back side of the bottom surface of the cavity 1, it is not bulky and can be reduced in weight. Also, in the case of arraying, there is an advantage that connection to a subsequent circuit is facilitated regardless of the element spacing.

  In the antenna device 10B as described above, since the circularly polarized wave excitation circuit is configured on the dielectric substrate 6, a filter, an amplifier, and the like connected to the subsequent stage can also be integrated on the dielectric substrate 6. Alternatively, a filter, an amplifier, or the like can be configured on another dielectric substrate and laminated with the dielectric substrate 6 for connection. In any case, there is an advantage that the antenna element portion and the subsequent feeding circuit portion can be connected in a space-saving manner.

  Here, the electrical characteristics of the antenna devices from the first embodiment to the third embodiment will be described with reference to FIG. FIG. 4 is a diagram showing electrical characteristics of the antenna device according to Embodiment 1-3 of the present invention.

  Here, the electrical characteristics when the height of the cavity 1 and the height of the non-excited conductor 4 in the antenna device 10A of Embodiment 2 are matched will be described as an example. 4A shows impedance characteristics of each L-shaped excitation probe 2A of the antenna apparatus 10A, FIG. 4B shows reflection characteristics, FIG. 4C shows a radiation pattern at a low-band resonance frequency, and FIG. ) Is a graph showing the axial ratio characteristics. As shown in FIGS. 4A and 4B, the impedance characteristics and reflection characteristics of the ports X1, X2, Y1, and Y2 are substantially overlapped. Further, in the antenna device 10A, since right-handed circularly polarized wave excitation is used, in FIG. 4C of the radiation pattern, RHCP (positive polarization component) is indicated by a solid line, and LHCP (cross polarization component) is indicated by a broken line. ing.

  In the impedance characteristic of the antenna device 10A shown in FIG. 4A, the kink resulting from the two resonance characteristics of the excitation patch conductor 3 and the non-excitation conductor 4 is formed in the vicinity of the Smith chart center, and good impedance characteristics are obtained. ing. This is the same in the reflection characteristics shown in FIG. 4B, and it can be confirmed that a broadband characteristic is obtained as a whole because of the desired two resonance characteristics. Further, as shown in FIGS. 4C and 4D, it can be seen that a good radiation pattern shape and low axial ratio characteristics are obtained at the low-band resonance frequency. Although not shown, it has been confirmed that good characteristics are obtained even at high-band resonance frequencies.

Embodiment 4 FIG.
An array antenna apparatus according to Embodiment 4 of the present invention will be described with reference to FIG. FIG. 5 is a plan view showing the configuration of the array antenna apparatus according to Embodiment 4 of the present invention.

  Any one of the antenna devices from the first embodiment to the third embodiment is used as an antenna element, and as shown in FIG. 5, a plurality of the antenna elements 10 (or 10A, 10B) are appropriately arranged to feed power, An array antenna apparatus can be configured. Even in such an array, the characteristics of the antenna devices from the first embodiment to the third embodiment are basically reflected, and the electrical characteristics are wideband (two resonance) characteristics and low axial ratio characteristics. In addition, it is possible to reduce the size and thickness of the feeder circuit.

  Here, when the side wall height of the cavity 1 is set relatively high, the beam width can be narrowed, and the amount of mutual coupling between adjacent antenna elements can be reduced. Moreover, since the amount of mutual coupling between adjacent antenna elements is reduced by the cavity 1, loss can be reduced.

  In the fourth embodiment, the array antenna apparatus is composed of 22 antenna elements. However, the present invention is not limited to this example, and the number of antenna elements constituting the array antenna apparatus can be appropriately determined according to specifications and the like.

  In the first to fourth embodiments, the configuration has been described with the dielectric substrate and the like omitted to show an ideal configuration. In contrast, in practice, for example, an excitation probe or a radiation conductor may be configured using a dielectric substrate, a film substrate, or the like. As for the radiation conductor, in the space application, a center short structure with a short pin or the like may be provided as a charge suppression measure.

  Furthermore, although the transmission system antenna device and the array antenna device have been described in the first to fourth embodiments, the present invention can also be applied to a reception antenna device and an array antenna device.

  1 metal cavity, 2 excitation probe, 2A L-shaped excitation probe, 2a inner conductor of coaxial line, 2b microstrip line, 3 excitation patch conductor, 4 non-excitation conductor, 5 holes, 6 dielectric substrate, 7 microstrip line, 10, 10A, 10B Antenna device.

Claims (6)

A top surface of a cylinder having a bottom surface of a predetermined shape is opened to a space, has an opening surface of a predetermined shape, a side wall from the bottom surface to the opening surface has a predetermined height, and a cavity constituted by a metal conductor;
A plate-like first radiating conductor disposed oppositely from the bottom surface of the cavity at a predetermined interval;
A plate-like second radiating conductor having a size different from that of the first radiating conductor and disposed opposite to the first radiating conductor at a predetermined interval;
The cavity is inserted between the bottom surface of the cavity and the first radiating conductor at a predetermined interval from both the bottom surface of the cavity and the first radiating conductor, and a tip portion is connected to the first radiating conductor by electromagnetic coupling. A first excitation probe electrically connected and having the other end connected to a circularly polarized wave excitation circuit via a side wall of the cavity;
It has the same configuration as the first excitation probe and rotates 90 degrees to one of the circumferential directions of the bottom surface of the cavity with respect to the first excitation probe when the center of the bottom surface of the cavity is used as a reference point. A second excitation probe that is arranged symmetrically and whose excitation phase is 90 degrees different from the excitation phase of the first excitation probe;
It has the same configuration as the first excitation probe and rotates 180 degrees to one of the circumferential directions of the bottom surface of the cavity with respect to the first excitation probe when the center of the bottom surface of the cavity is used as a reference point. A third excitation probe that is arranged symmetrically and whose excitation phase is 180 degrees different from the excitation phase of the first excitation probe;
It has the same configuration as the first excitation probe and rotates 270 degrees to one of the circumferential directions of the bottom surface of the cavity with respect to the first excitation probe when the center of the bottom surface of the cavity is used as a reference point. And a fourth excitation probe arranged symmetrically and having an excitation phase that is 270 degrees different from the excitation phase of the first excitation probe. The antenna device according to claim 1, wherein a part of the side wall of the cavity is a discontinuous metal conductor. A top surface of a cylinder having a bottom surface of a predetermined shape is opened to a space, has an opening surface of a predetermined shape, a side wall from the bottom surface to the opening surface has a predetermined height, and a cavity constituted by a metal conductor;
A plate-like first radiating conductor disposed oppositely from the bottom surface of the cavity at a predetermined interval;
A plate-like second radiating conductor having a size different from that of the first radiating conductor and disposed opposite to the first radiating conductor at a predetermined interval;
The cavity is inserted between the bottom surface of the cavity and the first radiating conductor at a predetermined interval from both the bottom surface of the cavity and the first radiating conductor, and a tip portion is connected to the first radiating conductor by electromagnetic coupling. A first L-shaped excitation probe electrically connected and having the other end connected to a circularly polarized wave excitation circuit via the bottom surface of the cavity;
The same configuration as that of the first L-shaped excitation probe, and the circumferential direction of the bottom surface of the cavity with respect to the first L-shaped excitation probe when the center of the bottom surface of the cavity is used as a reference point A second L-shaped excitation probe which is arranged so as to be 90-degree rotationally symmetric with respect to one of the first L-shaped excitation probe and whose excitation phase is 90 degrees different from the excitation phase of the first L-shaped excitation probe;
The same configuration as that of the first L-shaped excitation probe, and the circumferential direction of the bottom surface of the cavity with respect to the first L-shaped excitation probe when the center of the bottom surface of the cavity is used as a reference point A third L-shaped excitation probe which is arranged so as to be 180-degree rotationally symmetric with respect to one of the first L-shaped excitation probe and whose excitation phase is 180 degrees different from the excitation phase of the first L-shaped excitation probe;
The same configuration as that of the first L-shaped excitation probe, and the circumferential direction of the bottom surface of the cavity with respect to the first L-shaped excitation probe when the center of the bottom surface of the cavity is used as a reference point A fourth L-shaped excitation probe that is arranged so as to be rotationally symmetric to 270 degrees to one of the two, and whose excitation phase is 270 degrees different from the excitation phase of the first L-shaped excitation probe. A feature antenna device. The antenna device according to claim 3, wherein a part of the side wall of the cavity is a discontinuous metal conductor. A dielectric substrate provided on the back surface of the bottom surface of the cavity;
A microstrip line provided as a circularly polarized wave excitation circuit on the back surface of the dielectric substrate that does not contact the back surface of the bottom surface of the cavity;
The surface of the dielectric substrate in contact with the back surface of the bottom surface of the cavity is covered with copper foil, and the copper foil on which the other end portions of the first, second, third and fourth L-shaped excitation probes are located And a hole of a predetermined size is provided only at the location of the dielectric substrate,
A circularly polarized wave excitation circuit provided on a back surface of the dielectric substrate, wherein tip portions of the first, second, third, and fourth L-shaped excitation probes pass through the holes in a non-contact manner; The antenna device according to claim 3 or 4, wherein the antenna device is connected. An array antenna apparatus comprising a plurality of antenna apparatuses according to any one of claims 1 to 5 arranged.

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