JPH1188043A - Antenna device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the antenna of a small frequency characteristic in a beam direction by positioning the probes near the center of a parallel plate waveguide. SOLUTION: The probes 13 are inserted into the parallel plate waveguide 1a from a micro strip line 2 near the center of the parallel plate waveguide 1a. The micro strip line 12 is excited at an almost equal phase by setting a plane wave excited into the parallel plate waveguide 1a to be standing wave feeding by the probes 13 with a power feeding part 5 constituted of a wave source 3a and a paraboloidal reflection wall 4. The micro strip line 12 is wired so that the micro strip antennas 11 operate as radiation elements which are connected to the micro strip line 12 in series with equal amplitude and equal phase. Thus, a radiation part 6 becomes almost uniform opening distribution and the radio wave can be radiated in a direction which is almost orthogonal to the radiation part 6. Then, impedance matching can freely be executed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a feeding type antenna device for transmitting a radio wave between two parallel flat conductors.

[0002]

2. Description of the Related Art An antenna of a feeding type for transmitting a radio wave between two parallel plate conductors has a planar configuration, and
Since low-loss characteristics can be obtained, it is particularly effective for millimeter-wave band antennas, and an application example as a forward-looking radar mounted on an automobile has been reported. FIG.
In July 4th, S.S. A. "LowC" by Zerubowski
ost Antenna Alternatives
for Automobile Radars ", MI
CROWAVE JOURNAL pp. It is a structural explanatory view of the conventional antenna device shown in 54-63,
(A) is a top view and (b) is a cross-sectional view. 1 in the figure
a and 1b are parallel plate waveguides composed of two parallel conductor plates, 2 is a plurality of radiation slots formed on one side of the parallel plate waveguide 1a, and 3b to 3d are parallel plate waveguides of the parallel plate waveguide 1b. A wave source 4 placed inside is a parabolic reflecting wall connecting the parallel-plate waveguides 1a and 1b, and a feeding source 5 is composed of the wave sources 3b to 3d and the parabolic reflecting wall 4. A radiating portion formed of an array of the plurality of radiating slots, a radio wave absorber, and a parabolic surface formed of the parallel plate waveguides and the parabolic reflecting wall; It is a bent part.

Next, the operation will be described. In this antenna device, parallel plate waveguides 1a and 1b are formed on the back surface of the radiating section 6 so as to form a two-layer structure, and the connection between these two-layer structure parallel plate waveguides 1a and 1b is parabolic reflection. The operation is performed by a parabolic bent portion 8 having a wall 4.
This is an antenna device having a configuration in which d is arranged. Wave sources 3b-3
The electromagnetic wave excited by the wave source d is a parallel plate waveguide 1b.
After being converted into a quasi-plane wave which can be regarded as a substantially plane wave by the paraboloidal reflecting wall 4 of the parabolic bent portion 8, propagates through the parallel plate waveguide 1a toward the radiating portion 6, and Are sequentially coupled to a plurality of radiation slots 2 provided therein, and are radiated as electromagnetic waves from each radiation slot 2. Since the electromagnetic wave supplied to the radiating section 6 is converted into a plane wave, only a plurality of slots in the radiating section 6 in the direction orthogonal to the traveling direction of the plane wave are arranged in the same row, and power is supplied in the same phase. Here, the residual power that has not been completely radiated from all the radiation slots 2 is wasted by the radio wave absorber 7 provided as an anti-reflection terminal provided in the parallel plate waveguide 1a. That is, the antenna device operates as an antenna by providing the feeder 5 that supplies a plane wave at a position coplanar with the radiator 6.

[0004] A conventional antenna device of a feeding type in which a radio wave travels between two parallel flat conductors is configured as described above. For example, it is compared with a planar antenna of another feeding type such as a microstrip line. And low loss characteristics, which is particularly effective in the millimeter wave band. Further, as compared with a reflector antenna or the like, there is an advantage that the whole device is not three-dimensional but two-dimensional and can be reduced in size.

[0005]

As described above, the conventional antenna device is of a traveling wave feeding type in which a plane wave traveling in the parallel plate waveguide 1a and the radiation slot 2 are coupled. To direct the normal beam in the normal direction of the radiating section 6, each radiating slot needs to be in phase. In the traveling wave feeding type, the reflection at each radiation slot for directing the beam to the front is also in phase, and the reflected wave becomes large. In this type of power supply, it is not easy to change the impedance, and there is a problem that impedance matching cannot be achieved. Therefore, usually, the beam is tilted from the front to shift the phase of the reflected wave to achieve matching. This tilt angle is often several tens degrees.

[0006] Another problem of the beam tilt antenna is a beam shift. Since the slots are sequentially fed by the traveling wave, the feed phase error increases in proportion to the feed length in the slot on the terminal side. Even an error of several degrees per slot becomes several tens of degrees at the terminal end, and the beam direction shifts. That is, there is a problem that the beam direction shifts due to design errors and manufacturing errors. Furthermore, even if a design is made at a certain frequency, if the frequency slightly changes, the beam direction changes, so that the frequency characteristics in the beam direction are large. As described above, the conventional antenna device has an essentially narrow band, and the applications that can be used are extremely limited.

[0007] With this type of traveling wave power supply, it is difficult to control the excitation amplitude. If the radiation from the slot at the input end is large, power is not transmitted to the end slot and a large amplitude taper is formed, so that the gain is greatly reduced. On the other hand, if the radiation from the slot is reduced, the power is transmitted to the terminal slot, but the remaining power is absorbed by the absorber and becomes a loss, so that the advantage of the power supply system with a reduced loss cannot be utilized. Further, in order to obtain 45 ° polarization, the slots need to be slanted. However, slanting the slots reduces the radiation resistance, so that the radiation from each slot decreases and the efficiency decreases. Therefore, there is a problem that the equal amplitude characteristic is not generally obtained and the gain is reduced.

Therefore, impedance matching can be easily achieved.
And the radiation direction of the beam becomes the normal direction of the radiation part 2,
It is another object of the present invention to provide an antenna device whose beam direction does not largely depend on the frequency and which can form a plurality of beams.

[0009]

In order to solve the above-mentioned problems, an antenna device according to a first aspect of the present invention provides an antenna for feeding a plane wave to the parallel plate waveguide at one input end of the parallel plate waveguide. It has a feed section composed of a wave source and a parabolic reflective wall, and has a microstrip antenna having a plane conductor on one side of the parallel-plate waveguide as a ground conductor. Feeding microstrip antennas arranged in the same direction, inserting probes arranged in a direction substantially perpendicular to the plane wave traveling direction near the center of the parallel plate waveguide from the microstrip line into the parallel plate waveguide, The microstrip line is excited by the probe and further the microstrip antenna is excited.

[0010] The antenna device according to a second aspect of the present invention includes:
In the vicinity of the center of the parallel plate waveguide, slits are arranged in a direction substantially perpendicular to the traveling direction of the plane wave in the parallel plate conductor on the side where the microstrip antenna is located, and the electromagnetic field in the parallel plate waveguide and the microstrip The line and the line are electromagnetically coupled by the slit to excite the microstrip line, and further to excite the microstrip antenna.

An antenna device according to a third aspect of the present invention includes:
In the antenna device, a bent portion where the parallel plate waveguide is bent by about 180 ° on the side where the microstrip line is not provided is provided, and a feeding portion for feeding a plane wave to the parallel plate waveguide is arranged on the back side where the microstrip antenna is not provided. It was done.

Further, an antenna device according to a fourth aspect of the present invention includes:
In the above antenna device, a barrier made of a radio wave absorber is added to the end of the parallel plate waveguide.

The antenna device according to a fifth aspect of the present invention includes:
In the above antenna device, the feed portion of the parallel plate waveguide is a lens and a wave source arranged substantially at a focal position of the lens.

An antenna device according to a sixth aspect of the present invention includes:
In the above antenna device, the microstrip antenna is polarized at an angle of approximately 45 ° with respect to the traveling direction of the plane wave.

Further, an antenna device according to a seventh aspect of the present invention includes:
In the antenna device, a radiation slot is used instead of the microstrip antenna.

An antenna device according to an eighth aspect of the present invention includes:
In the antenna device, a plurality of wave sources constituting the feeder are arranged.

Further, an antenna device according to a ninth aspect of the present invention includes:
In the antenna device, a plurality of wave sources constituting the feeder are arranged, and the wave sources are integrated with an MMIC, and the MMIC switch or the like is used to switch and excite the wave source.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. FIG. 1 is a schematic configuration diagram showing Embodiment 1 of the present invention. (A) is an overall view, (b) is a plan view inside a parallel plate waveguide, and (c) is a cross-sectional view. In the figure, 1a is a parallel plate waveguide composed of two parallel conductor plates, and 9 is a plate surface on one side of the parallel plate waveguide 1a and acts as a ground conductor. Reference numeral 10 denotes a dielectric substrate formed above the ground conductor 9, and reference numeral 11 denotes a microstrip antenna which functions as a radiation element. The microstrip antenna 11 is fed in series by a microstrip line 12 wired in a direction substantially parallel to the traveling direction of the plane wave inside the parallel plate waveguide 1a, and is radiated by an array of a large number of microstrip antennas. 6 is constituted. The microstrip antenna has a simple structure, and can be easily manufactured by simply etching a copper-clad dielectric substrate. Therefore, cost reduction, thinning, and miniaturization are possible. In addition, a thin antenna that can be easily manufactured by one etching can be obtained by forming a feed line of a power combining / distributing circuit or the like with a microstrip line on the same plane as a radiating element. Reference numeral 13 denotes a microstrip line 1 near the center of the parallel plate waveguide 1a.
2 is a probe inserted into the parallel plate waveguide 1a. In addition, the configuration of the power supply unit 5 including the wave source 3a and the parabolic reflection wall 4 is exactly the same as that of the conventional device.

Next, the operation will be described. The wave source 3a is formed in a shape such as a waveguide inside the parallel plate waveguide 1a, and radiates an electromagnetic wave toward the parabolic reflection wall 4 from an opening provided in the waveguide. The above-mentioned waveguide is taken out from the back surface of the parallel plate waveguide 1a by a three-dimensional circuit such as a waveguide corner or a waveguide bend, or a coaxial waveguide converter or the like, so that the electrical interface of the antenna device according to the present invention is obtained. Points. The opening of the waveguide acting as the wave source 3a may be tapered like a horn antenna. The plane wave excited inside the parallel-plate waveguide 1a by the feeding unit 5 composed of the wave source 3a and the parabolic reflecting wall 4 makes the microstrip line 12 almost equal by feeding the standing wave by the probe 13 to the microstrip line. Excitation in phase. Then, by arranging the microstrip line so that the microstrip antenna 11 fed in series to the microstrip line 12 is fed with equal amplitude and equal phase, the radiating section 6 has a substantially uniform aperture distribution, and 6 can be radiated in a direction substantially orthogonal to 6. Further, since the feed line is constituted by the microstrip line, the impedance can be freely matched.

Further, since the probe 13 for exciting the microstrip line 12 is arranged near the center of the microstrip line 12, the phase of the radiating section 6 when the frequency slightly deviates from the design center frequency is obtained. Since the distribution appears as a phase advance or a phase delay that is substantially line-symmetric with respect to the line on which the probes 13 of the radiating section 6 are arranged, there is almost no change in the beam direction due to a frequency change. Further, even if the excitation amplitude phase of the microstrip antenna is disturbed and the beam is tilted, the tilt can be canceled because the beam is symmetrically arranged with respect to the feeding point.

The present invention is also effective when the excitation distribution of the microstrip antennas 11 arranged by the microstrip line 12 in a direction substantially parallel to the traveling direction of the plane wave inside the parallel plate waveguide is not uniform. For example, it is also possible to obtain a low side lobe type antenna device as a Taylor distribution. Furthermore, by giving the microstrip line an appropriate phase distribution,
It is also possible to shift the beam from an axis perpendicular to the radiating section 6. Although the figure shows an example of a square microstrip antenna as a radiating element, other similar effects can be obtained by using a rectangular microstrip antenna, a circular microstrip antenna, or the like.

Embodiment 2 FIG. FIG. 2 is a schematic configuration diagram showing Embodiment 2 of the present invention. (A) is an enlarged view of a part of an array arrangement of the same microstrip antenna 11 as in the embodiment, and (b) is a sectional view. In the figure, 14
Is a slit provided in the ground conductor 9, and the plane wave excited inside the parallel plate waveguide 1 a by the feeder 5 is electromagnetically coupled to the microstrip line 12 by the slit 14 at substantially the same phase to form the microstrip line 12. To excite. The operation in which the microstrip line 12 excites the microstrip antenna 11 is described in the first embodiment.
The beam can be radiated on an axis substantially perpendicular to the radiating section 6. As described above, in the second embodiment of the present invention, power is supplied in the form of electromagnetic coupling. Therefore, the probe 13 as in the first embodiment is not required, the configuration is simplified, and the manufacture is facilitated.

Embodiment 3 FIG. FIG. 3 is a schematic configuration diagram showing Embodiment 3 of the present invention. (A) is an overall view, (b)
Is a sectional view. In the figure, a feeder 5 composed of a wave source 3a and a parabolic reflecting wall 4 is arranged inside a parallel plate waveguide 1b installed on the back of the parallel plate waveguide 1a. Here, the parallel plate waveguides 1a and 1b are connected by a bent portion 15 such that the parallel plate waveguide can be regarded as an E-plane corner of the wide waveguide. The configurations of the parallel plate waveguide 1a and the radiation section 6 are exactly the same as those in the first embodiment. Since the power supply unit 5 is provided on the rear surface of the radiation unit 6, the size can be reduced. Also, the bent portion is not a parabolic bent portion as in the conventional antenna device, but has a linear shape that can be regarded as an E-plane corner of a wide waveguide, so that machining becomes easy, and When the hardware is divided at the bent portion, the assembling accuracy can be relaxed compared to the parabolic bent portion, so that an antenna device that is easy to process and assemble can be obtained. The plane wave generated in the parallel plate waveguide 1 b by the feeder 5 is propagated to the parallel plate waveguide 1 a by the bent portion 15, and is radiated by the radiation portion 6 to the radiation portion 6.
The beam can be emitted on an axis substantially orthogonal to. In the figure, a method using the same probe 13 as in the first embodiment is shown as a method for exciting the microstrip line 12 from the electromagnetic field inside the parallel plate waveguide 1a. Slit 14 in ground conductor 9
May be provided to supply power to the microstrip line by electromagnetic coupling.

Embodiment 4 FIG. 4 is a sectional view showing Embodiment 4 of the present invention. In the figure, reference numeral 7 denotes a barrier made of a radio wave absorber. Of the power of the plane wave inside the parallel plate waveguide 1a, the power that cannot be coupled to the probe 13 or the slit 14 is the terminal of the parallel plate waveguide. In order to prevent the reflection at the end of the parallel plate waveguide and the power reflected at the end of the parallel plate waveguide, the probe 13 or the slit 1
4 and is inserted for the purpose of preventing the microstrip antenna 11 constituting the radiation section 6 from disturbing the aperture distribution of the array arrangement. In the drawing, as in the third embodiment, the feeding portion 5 is formed by using the bent portion 15 of the parallel plate waveguide.
Is arranged in the parallel plate waveguide 1b on the back side of the radiating portion 6, but the power is supplied to the coplanar plane with the parallel plate waveguide 1a without using the bent portion 15 as in the first embodiment or the second embodiment. The unit 5 may be provided.

Embodiment 5 FIG. FIG. 5 is a schematic configuration diagram showing Embodiment 5 of the present invention. (A) is a plan view of the inside of the parallel plate waveguide 1b, and (b) is a cross-sectional view. In the figure, reference numeral 16 denotes a lens, which constitutes the feeding unit 5 together with a wave source 3a disposed near the focal point of the lens 16, and can convert an electromagnetic wave excited by the wave source 3a into a plane wave inside the parallel plate waveguide 1b. The electromagnetic wave excited from the wave source 3a proceeds in the traveling direction as it is, passes through the lens 16 and becomes a plane wave, and is supplied to the radiation section 6 via the bent section 15. The operation of the radiating section 6 is exactly the same as in the above embodiment. Unlike the conventional antenna device, the wave source 3a does not block the path of the plane wave in the parallel plate waveguide, so-called blocking, so that the loss can be reduced and the side lobe can be reduced. In addition, since blocking does not occur, the disturbance of the electromagnetic field inside the parallel plate waveguide can be reduced, so that there is an advantage that the aperture distribution of the radiating portion 6 can be easily adjusted to the design value. In the figure, an example is shown in which the feeder 5 is disposed on the parallel plate waveguide 1b on the back side of the radiating portion 6 by using the bent portion 15 of the parallel plate waveguide as in the third embodiment. Alternatively, the feeder 5 may be arranged coplanar with the parallel plate waveguide 1a without using the bent portion 15 as in the second embodiment. Further, in the figure, the shape of the lens 16 is a so-called convex lens type. However, the same effect can be obtained even if the shape of the lens 16 is any shape that can convert an electromagnetic wave excited by the wave source 3a into a plane wave.

Embodiment 6 FIG. FIG. 6 is a schematic configuration diagram showing Embodiment 6 of the present invention, and is a plan view of the radiation section 6. In the figure, 11 is a microstrip antenna,
Reference numeral 12 denotes a microstrip line, and reference numeral 13 denotes a probe inserted from the microstrip line 12 into the parallel plate waveguide 1a, which is exactly the same as that in the first embodiment.
Numeral 17 indicates the direction of polarization of the radiated radio wave. Generally, the polarization direction of the microstrip antenna is determined by the microstrip line 12 and the microstrip antenna 11.
Feeding point connecting microstrip antenna 11
Is parallel to a straight line connecting to the center point of. Therefore, by arranging the feeding point at an angle of approximately 45 ° with respect to the plane wave traveling direction inside the parallel plate waveguide 1a with respect to the microstrip antenna 11, the feeding point is approximately 45 ° with respect to the plane wave traveling direction. Can be excited. For example, in an antenna for a forward surveillance radar mounted on a car, application of 45 ° oblique polarization to the ground for the purpose of avoiding radio wave interference with an oncoming radar wave has been studied. When an antenna device that emits an oblique 45-degree polarized wave is applied as an antenna for a forward monitoring radar mounted on an automobile, the mounting direction of the antenna device can be set to be horizontal or vertical with respect to the vehicle body.
が な い Since there is no need to install the device at an angle, the occupied area of the entire device can be reduced. Here, the polarization is obliquely 45 °, but the polarization direction can be freely changed by changing the position of the feeding point.

Embodiment 7 FIG. 7 is a schematic configuration diagram showing Embodiment 7 of the present invention. (A) is an overall view, (b)
Is a sectional view. In the figure, reference numeral 18 denotes a conductor plate arranged on the dielectric substrate 10, and 2 denotes a radiation slot provided in the conductor plate 18. The electromagnetic field inside the parallel plate waveguide 1a is transmitted to the radiation slot 2 by the slit 14 provided in the ground conductor 9.
And emits a radio wave in a direction substantially orthogonal to the radiation section 6. Generally, when a microstrip antenna is fed by a microstrip line, a high-impedance line is required to match the microstrip line with the microstrip antenna. Microstrip lines have high line impedance when the line width is narrow, but when the microstrip line is applied to the millimeter wave band, the line width is considerably narrow, so the loss increases, and the accuracy when manufacturing by etching etc. Management must be strict. Embodiment 7 of the present invention
By using radiation slots instead of microstrip antennas, the loss can be reduced, and an inexpensive antenna that is easy to manufacture can be obtained. In the figure, an example of a 45 ° polarized wave is shown as an example of a radiation slot. However, since the present invention does not particularly depend on the polarization direction, the radiation slot may be provided in any direction.

Embodiment 8 FIG. 8 is a schematic configuration diagram showing Embodiment 7 of the present invention. (A) is an overall view, (b)
Is a sectional view. In the figure, 3b to 3d are lenses 16
The wave source 3c is arranged in the vicinity of the focal point of the lens 16 in particular. Reference numeral 19 denotes a virtual plane orthogonal to the traveling direction of the plane wave inside the parallel plate waveguide 1a, and reference numerals 20a to 20c denote beam directions in the plane of the virtual plane 19 of the antenna device according to the eighth embodiment.
0a indicates the normal direction of the radiation section 6. The electromagnetic wave excited by the wave source 3c is applied to the parallel plate waveguide 1 by the lens 16.
b, a plane wave is propagated to the parallel plate waveguide 1a by the bent portion 15 and is transmitted from the radiation portion 6 to the normal direction 2 of the radiation portion 6.
Emitting a beam at 0a is exactly the same as in the above embodiment. The electromagnetic wave excited by the wave source 3b or 3d arranged at a position slightly shifted from the focal point of the lens 16 also becomes a plane wave by the lens 16, but the phase distribution of those wave fronts is inclined with respect to the virtual plane 19. Therefore, a multi-beam antenna capable of tilting a beam in the virtual plane is obtained. Although the figure shows the case of three wave sources, the number of wave sources is not particularly limited as long as the wave sources can be further arranged near the focal point of the lens 19. In FIG. 8, the wave source 3c is disposed very close to the focal point of the lens 16 so that at least one beam is
The example in which the beam is radiated in the normal direction 20a of the radiating section 6 is shown. However, when the beam does not need to be directed in the normal direction 20a of the radiating section 6, for example, the beam is slightly inclined from the normal direction 20a of the radiating section 6. In the case where the two beams are formed and applied as a monopulse antenna, it is not necessary to arrange at least one of the plurality of wave sources arranged near the focal point of the lens 16 very close to the focal point of the lens 16. Also, by using the parabolic reflective wall 4 instead of the lens 16,
The same effect can be obtained when a plurality of the parabolic reflective walls 4 are arranged near the focal point.

Embodiment 9 FIG. 9 is a schematic configuration diagram showing Embodiment 7 of the present invention. MM according to the eighth embodiment.
IC (Monolitic Microwave I)
integrated circuit). A small and lightweight electronically controlled antenna that can radiate by arbitrarily switching a plurality of beams generated by the wave sources 3b to 3d by the MMIC 21 is obtained. This MMIC21
Includes circuits such as switching means for switching beams and a transceiver.

[0030]

According to the first aspect of the present invention, a feeder comprising a wave source for feeding a plane wave to the parallel plate waveguide and a parabolic reflection wall is provided at one input end of the parallel plate waveguide. A microstrip antenna having a plane surface on one side of the parallel plate waveguide as a ground conductor, and feeding the microstrip antennas arranged in a direction substantially the same as the plane wave traveling direction by the microstrip line, Probes arranged in a direction substantially perpendicular to the plane wave traveling direction near the center of the plate waveguide are inserted from the microstrip line into the parallel plate waveguide, and the microstrip line is excited by the probe to form the microstrip. Since the antenna is configured to be excited, it is possible to obtain an antenna in which the radiation direction of the beam is almost normal to the radiation part. There is. Further, by setting the probe insertion position near the center of the parallel plate waveguide, an antenna having a small frequency characteristic in the beam direction can be obtained. Further, since the feed line is constituted by the microstrip line, there is an effect that the impedance can be freely matched.

According to the second aspect of the present invention, since the electromagnetic field in the parallel plate waveguide and the microstrip line are electromagnetically coupled to each other, there is an effect that the configuration is simple and the manufacture is easy.

According to the third aspect of the present invention, in the antenna device, a bent portion is formed by bending the parallel plate waveguide by about 180 ° on the side where the microstrip line is not provided, and a plane wave is supplied to the parallel plate waveguide. By arranging the feeding part on the back side without the microstrip antenna, there is an effect that the size can be reduced.

According to the fourth aspect of the present invention, a barrier made of a radio wave absorber is added to the end of the parallel plate waveguide, so that the parallel plate waveguide of residual power that cannot be completely coupled by the probe or the electromagnetic coupling slit. It is possible to reduce the reflection at the terminal end, improve the reflection characteristics of the antenna, and reduce the beam disturbance.

According to the fifth aspect of the present invention, since the parabolic reflecting wall acting to convert the electromagnetic wave excited by the wave source into a plane wave is formed as a lens, there is no blocking by the wave source and the reflection of the antenna. There is an effect that characteristics can be reduced and radiation characteristics with high gain and low side lobe can be obtained.

According to the sixth aspect of the present invention, the microstrip antenna is made to have a substantially 45 ° polarization with respect to the traveling direction of the plane wave, so that the 45 ° polarization can be easily radiated without deteriorating the radiation characteristics. There is an effect that an antenna that can be obtained can be obtained. When this effect is applied to an antenna for a forward monitoring radar mounted on an automobile, there is an effect that radio interference with an oncoming vehicle can be reduced without increasing the size of the apparatus.

According to the seventh aspect of the present invention, the radiation slot is used in place of the microstrip antenna, so that a low-loss and low-cost antenna can be obtained.

According to the eighth aspect of the present invention, since a plurality of wave sources constituting the feed section are arranged, a multi-beam antenna radiating a plurality of beams in a plane orthogonal to a plane wave in the parallel plate waveguide is provided. There is an effect that can be obtained.

According to the ninth aspect of the present invention, a plurality of wave sources constituting the power supply unit are arranged, and the wave sources and the MMI
By integrating the C switch, the size is reduced, and there is an effect that an electronically controlled antenna that switches and emits a plurality of beams in a plane orthogonal to the plane wave in the parallel plate waveguide is obtained.

[Brief description of the drawings]

FIG. 1 is a first embodiment of an antenna device according to the present invention;
FIG.

FIG. 2 is a second embodiment of the antenna device according to the present invention;
FIG.

FIG. 3 is a third embodiment of the antenna device according to the present invention;
FIG.

FIG. 4 is a fourth embodiment of the antenna device according to the present invention;
FIG.

FIG. 5 is a fifth embodiment of the antenna device according to the present invention;
FIG.

FIG. 6 shows an antenna device according to a sixth embodiment of the present invention;
FIG.

FIG. 7 is a seventh embodiment of the antenna device according to the present invention;
FIG.

FIG. 8 is an eighth embodiment of the antenna device according to the present invention;
FIG.

FIG. 9 is a ninth embodiment of the antenna device according to the present invention;
FIG.

FIG. 10 is a schematic configuration diagram showing an example of the configuration of a conventional antenna of a power supply type for transmitting a radio wave between two parallel plate conductors.

[Explanation of symbols]

1 parallel plate waveguide, 2 radiation slot, 3 wave source, 4
Parabolic reflective wall, 5 feed section, 6 radiating section, 7 radio wave absorber, 8 parabolic bent section, 9 ground conductor, 10 dielectric substrate, 11 microstrip antenna, 12
Microstrip line, 13 probe, 14 slit, 15 bent part, 16 lens, 17 polarization direction, 18 conductor plate, 19 virtual plane, 20 beam direction, 21 MMIC.

Claims (9)

[Claims] A conductor wall for holding the two parallel plate conductors and the parallel plate conductor with a certain gap therebetween and a first end surface of the parallel plate conductor and a side opposed to the first end surface; A parallel plate waveguide disposed on a second end surface of the parallel plate waveguide, an input end including a third end surface of the parallel plate waveguide on a side without the conductor wall, and the third end surface of the parallel plate waveguide. A fourth end face on the side opposite to
A power supply unit composed of a wave source and a parabolic reflective wall for feeding a plane wave to the parallel plate waveguide on the input end side, and a plate surface on one side of the parallel plate waveguide as a ground conductor, A plurality of microstrip antennas each including a dielectric substrate on the ground conductor and a radiating element on the dielectric substrate; and a microstrip including the ground conductor and the dielectric substrate on the same plane as the radiating element. A line, a line structure in which the plurality of microstrip antennas arranged in substantially the same direction as the plane wave traveling direction in the parallel plate waveguide are connected to the microstrip line and fed, and a line structure. And the plane wave propagation in the vicinity of substantially the center of each of the rows constituting the array and in the vicinity of the center of the parallel plate waveguide. Direction substantially probes arranged in a direction perpendicular is constituted by the inserted structure in the parallel-plate waveguide from the microstrip line of the respective antenna devices. 2. A conductor wall for holding two parallel flat conductors and said parallel flat conductor with a certain gap therebetween, and a first end face of said parallel flat conductor and a side facing said first end face. A parallel plate waveguide disposed on a second end surface of the parallel plate waveguide, an input end including a third end surface of the parallel plate waveguide on a side without the conductor wall, and the third end surface of the parallel plate waveguide. A fourth end face on the side opposite to
A power supply unit composed of a wave source and a parabolic reflective wall for feeding a plane wave to the parallel plate waveguide on the input end side, and a plate surface on one side of the parallel plate waveguide as a ground conductor, A plurality of microstrip antennas each including a dielectric substrate on the ground conductor and a radiating element on the dielectric substrate; and a microstrip including the ground conductor and the dielectric substrate on the same plane as the radiating element. A line, a plurality of microstrip antennas arranged in substantially the same direction as the plane wave traveling direction in the parallel plate waveguide, a single-row structure connected to the microstrip line and fed, and a single-row structure. A plurality of array arrays, and the micro-storage near the center of each of the rows constituting the array and near the center of the parallel plate waveguide. A plurality of slits and the configured antenna device arranged in a direction substantially perpendicular with the plane wave traveling direction parallel flat conductors of a side of the Ppuantena. 3. In the vicinity of an end of an array arrangement composed of a plurality of microstrip antennas, a parallel plate waveguide can be regarded as an E-plane corner of a wide waveguide.
A bent portion formed by bending the parallel plate waveguide to the side without the microstrip antenna by about 180 °; a wave source and a parabolic reflection wall for feeding a plane wave to the bent portion and the parallel plate waveguide; The power supply unit is connected to the power supply unit, and the power supply unit is arranged on the back side of the parallel plate waveguide where the microstrip antenna is not provided. The antenna device as described in the above. 4. The antenna device according to claim 1, wherein a barrier made of a radio wave absorber is formed on the terminal side of the parallel plate waveguide. 5. A power supply unit comprising a lens and a wave source disposed at a substantially focal point of the lens on the input side of the parallel plate waveguide.
The antenna device according to any one of the above. 6. The microstrip antenna according to claim 1, wherein said microstrip antenna has a plane of polarization that is at a substantially 45 ° angle to the direction of the direction vector of the plane wave propagation direction in said parallel plate waveguide. The antenna device according to any one of the above. 7. A radiation slot instead of the microstrip antenna.
7. The antenna device according to any one of 6. 8. A wave source constituting said feed portion of said plurality of parallel plate waveguides arranged in a direction substantially perpendicular to a plane wave traveling direction in said parallel plate waveguide, and said wave sources are excited. Forming a plurality of beams in a plane orthogonal to the plane wave traveling direction by
8. The antenna device according to any one of 7. 9. A wave source constituting the feed portion of the parallel plate waveguide, which is arranged in a direction substantially perpendicular to a plane wave traveling direction in the parallel plate waveguide, and a wave source integrated with the wave sources. MMIC (Monolitic Mic)
rowaveIntegrated Circuit)
And a beam direction in a plane orthogonal to the plane wave traveling direction can be switched by switching and exciting the wave source using switching means such as the MMIC switch. 8. The antenna device according to any one of 7.