JPH1032425A - Antenna system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an antenna system which does not deteriorate a reflective characteristic at an input terminal and is capable of beam-scanning electrically by providing a plane wave power feeding part at both ends of a radiation part and feeding power through a divider dividing into two. SOLUTION: All the electromagnetic waves radiated from rectangular radiation holes 5 are not synthesized with a normal direction vertical to a parallel flat panel including the advancing directions 7a and 7b of the radio waves 7a and 7b, and radio waves by a plane wave are synthesized in a direction obtained by shifting from the normal direction by an angle -θ. Consequently, all the synthetic waves from the radiation holes 5 energized by each plane wave become a synthetic beam of two beams directed to an angle ±θ. Consequently, at the time of setting the arraying internals of the radiation holes 5 to be a value less than a wavelength λg within a parallel flat panel conductor and close to the wavelength λg, each beam formed by each plane wave is directed to the neighborhood of the normal direction of the parallel flat panel to make a front beam with peak power in a normal direction. In addition reflected waves at each radiation hole 5 do not intensify each other by the same phase so that a reflecting characteristic is also satisfactory.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art FIG. 10A shows an IEEE standard in 1981.
AP-S Symposium Digest Vo
l. Ipp. 207-208, and FIG. 10B is a front view of a conventional antenna device disclosed in Japanese Patent Application Laid-Open No. 6-260834. In the figure, 1 is a dielectric substrate whose surface is covered with a conductor, 2 is a feeding point, 3 is a feeding waveguide formed by a plurality of through holes, and 4 is a focus on the phase center of the feeding waveguide 3. 5 is a rectangular radiation hole formed by etching on one surface of the dielectric substrate 1 whose surface is covered with a conductor, 6 is a radiation portion composed of the plurality of rectangular radiation holes 5, and 7 is the radiation portion. The traveling direction of radio waves propagating inside the dielectric substrate 1 whose surface is covered with a conductor, 14 is a circular radiation hole formed by etching on one surface of the dielectric substrate 1 whose surface is covered with a conductor, 21 is the feed point 2 Is a semicircular reflector centered at. The rectangular radiation hole 5 and the circular radiation hole 14 are arranged at an interval d in a direction perpendicular to the traveling direction 7 of the radio wave in the radiation section 6. At intervals S = λg (λg: wavelength in the parallel plate conductor), the circular radiation holes 14 are arranged at intervals S determined by the beam direction. The polarization planes of the rectangular radiation hole 5 and the circular radiation hole 14 are parallel to the traveling direction 7 of the radio wave in the radiation part 6. The thickness of the dielectric substrate is smaller than １ ／ of the wavelength of the radio wave used in the dielectric, and the dielectric substrate 1 whose surface is covered with a conductor is like a parallel plate waveguide.

Next, the operation will be described. First, FIG. 10A will be described. The electric wave fed from the feeding point 2 propagates in a cylindrical shape. Of these, those that have propagated to the semicircular reflector 21 are reflected by the semicircular reflector 21 and return to the feed point 2, and then propagate to the reflecting wall 4. The radius of the semicircular reflector 21 is λg / 4 (λg: wavelength in the parallel plate conductor), and the phase of the radio wave returning to the feeding point 2 is delayed by exactly 2π. Therefore, the radio wave has the same phase as the radio wave propagated to the reflection wall 4 from the beginning. As a result, all the radio waves emitted from the feeding point 2 propagate as semi-cylindrical waves centered on the feeding point 2 toward the reflecting wall 4. After being reflected by the reflecting wall 4, the half-cylindrical wave propagates as a plane wave in the traveling direction 7 of the radio wave, and excites the rectangular radiation hole 5 in the middle. The plurality of rectangular radiation holes 5 are arranged at intervals of S = λg with respect to the traveling direction of the plane wave, and all the rectangular radiation holes 5 are excited in phase. Therefore, the antenna device shown in FIG. 10A forms a beam in a direction perpendicular to the parallel plate.
In the conventional antenna device, the rectangular radiation hole 5 has a longer length as the plane wave travels. This is because the plane wave attenuated by the radiation is more strongly coupled to the rectangular radiation holes 5 so that the power radiated from each rectangular radiation hole 5 is equalized. As a result, the aperture distribution of the antenna device becomes uniform, and the gain increases. Next, FIG.
The conventional antenna device shown in FIG. 10A is different from the conventional antenna device shown in FIG. 10A in that a feeding waveguide 3 formed by a plurality of through holes is used instead of the semicircular reflector 21 so that the reflecting wall 4 is formed from the feeding point 2 to the reflecting wall 4. The point is that a cylindrical wave is supplied, and the circular radiation hole 14 is used instead of the rectangular radiation hole 5. Therefore, the basic operation is the same as that of the conventional antenna device shown in FIG. 10A and FIG.
In the conventional antenna device shown in FIG. 2B, the rectangular radiation hole 5 and the circular radiation hole 14 are arranged at an arbitrary interval S in the traveling direction 7 of the radio wave instead of λg. The beam can be shifted in a desired direction in a plane perpendicular to the parallel plate.

[0004]

Since the conventional antenna device is configured as described above, if it is desired to form a front beam in a normal direction perpendicular to the parallel flat plate, the antenna device will not travel in the direction of propagation of the radio wave of each radiation hole. Is required to be S = λg (λg: wavelength in the parallel plate conductor). Therefore, the reflected waves of the plane waves propagating in the parallel plate at the respective radiation holes are strengthened in phase, and the reflection of the antenna device is increased. There is a problem that characteristics are deteriorated. Although the beam direction can be shifted by setting the arrangement interval S to an arbitrary interval instead of λg as described above, since the beam is a fixed beam, the entire antenna device is mechanically rotated to perform beam scanning. In addition, there is a problem that the fixed beam must be mechanically scanned, and the size of the entire antenna device including the mechanical drive unit increases and the weight increases.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and the reflection characteristic at the antenna input end, that is, the VSWR does not deteriorate even if a front beam is formed in a normal direction perpendicular to the parallel plate. An object of the present invention is to obtain an antenna device and an antenna device that can electronically scan a beam.

[0006]

In the antenna device according to the first aspect of the present invention, a plurality of radiating holes are arranged on one surface of the parallel plate conductor in a predetermined direction at an interval of λg (λg: wavelength in the parallel plate conductor). Arranged so as to be less than, a radiating portion in which a parallel plate conductor is formed by providing a dielectric between the parallel plate conductors facing at least the region where the radiation holes are provided, and a parabolic surface shape. A reflecting wall having a wave source disposed at the focal point of the parabolic surface, a plane wave feeder provided at each end of the radiator, and feeding a plane wave having the traveling direction in the fixed direction to the radiator. , A bi-divider is connected to the input end of the wave source of each of the plane wave feed units, and power is supplied through the bi-divider.

An antenna device according to a second aspect of the present invention comprises:
A plurality of radiating holes are arranged on one surface of the parallel plate conductor such that an arrangement interval in a certain direction is smaller than λg (λg: wavelength in the parallel plate conductor), and at least in a region where the radiating holes are provided. A radiation portion having a parallel plate waveguide formed by providing a dielectric between the opposed parallel plate conductors, a reflecting wall having a parabolic surface shape, and a wave source arranged at a focal point of the parabolic surface; Switches provided at both ends of the section, for supplying a plane wave having the predetermined direction as the traveling direction to the radiating section, and having a two-terminal switching function at an input terminal of a wave source of each of the plane wave feeding sections. Are connected to one terminal of the other end of each switch, respectively, and a two-divider is connected to the other terminal of each switch. The other end of each of the switches is connected to the other terminal and to the two-divider. Switchable 3 terminals E connects the switch having a function, is intended to feed through a switch having the three-terminal switching function.

[0008] An antenna device according to a third aspect of the present invention comprises:
The antenna device according to claim 1 or 2,
An arrangement interval of a plurality of radiation holes on one side of the parallel plate conductor in a certain direction is smaller than λg (λg: wavelength in the parallel plate conductor),
In addition, they are arranged so that their polarization directions are at 45 degrees with respect to the fixed direction.

An antenna device according to a fourth aspect of the present invention is
The antenna device according to claim 1 or 2,
The radiation holes arranged on one side of the parallel plate conductor are arranged such that one of the radiation holes has its polarization direction set to 45.
At an angle of λg /
The next radiation hole whose polarization direction is orthogonal to the polarization direction of the radiation hole is disposed at a distance of 4 (λg: wavelength in the parallel plate conductor), and a pair of circular polarization is formed by the two radiation holes. A wave radiating hole element is formed, and the pair of circularly polarized radiating hole elements is arranged at an interval of less than λg (λg: wavelength in a parallel plate conductor) in the above-mentioned fixed direction, and is a mirror image of an intermediate point in the above-mentioned fixed direction A plurality are arranged so as to be related.

An antenna device according to a fifth aspect of the present invention comprises:
5. The antenna device according to claim 1, wherein the radiation hole or the circularly polarized radiation hole element is arranged so as to be symmetrical or mirror-image with respect to an intermediate point in the fixed direction. In a certain direction, the shape of the radiation hole or the circularly polarized radiation hole element is set based on the relationship with the amplitude change of the plane wave, and a desired radiation pattern is formed in the constant direction.

The antenna device according to the invention of claim 6 is:
5. The antenna device according to claim 1, wherein the radiation hole or the circularly polarized radiation hole element is arranged so as to be symmetrical or mirror-image with respect to an intermediate point in the fixed direction. For each of the fixed direction and the direction orthogonal to the fixed direction, set the shape and size of the radiation hole based on the relationship with the amplitude change of the plane wave,
A desired radiation pattern is formed in each of the fixed direction and a direction orthogonal to the fixed direction.

An antenna device according to a seventh aspect of the present invention comprises:
The antenna device according to claim 5 or 6,
A radio wave absorber is provided at an intermediate point in the fixed direction between the parallel plate conductors.

The antenna device according to the invention of claim 8 is:
The antenna device according to any one of claims 1 to 7, wherein the parallel plate conductor faces at least a region where the radiation hole or the circularly polarized radiation hole element is provided, instead of the dielectric of the radiation portion. The internal conductor of the parallel plate conductor is arranged as a corrugated concavo-convex surface conductor in the fixed direction.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram illustrating the configuration of an antenna device, and FIG.
FIG. 3 is a block diagram, and FIG. 3 is an explanatory diagram for explaining a traveling direction of a radio wave, and 1 to 7 correspond to the description of the conventional antenna device. In the figure, the arrangement interval S of the rectangular radiation holes 5 formed in the radiation section 6 in the traveling directions 7a and 7b of the radio wave is set to be smaller than λg (λg: wavelength in the parallel plate conductor). Reference numeral 8 denotes a beam direction θ on the XZ plane orthogonal to the parallel plate including the traveling direction 7 of the radio wave, 9 denotes a two-way distributor connected to the feeding points 2a and 2b, and 10 denotes a two-way splitter.
The input terminals of the distributor, 11a and 11b,
a, the feeding waveguide 3a, the reflecting wall 4a and the feeding point 2b, the feeding waveguide 3b, and the reflecting wall 4
b, the plane wave feeders 12a and 12b simulate the plane waves fed from the plane wave feeders 11a and 11b, respectively. Here, the thickness of the dielectric substrate whose surface is covered with a conductor is 1/1 / the wavelength in the dielectric of the radio wave used.
2, the entire dielectric substrate is formed as a parallel plate waveguide that can be regarded as TEM mode propagation. Since a dielectric was provided at least in the parallel plate at a position corresponding to the portion where the rectangular radiation hole 5 was formed, the permittivity inside and outside the parallel plate was changed to change the propagation phase speed of the radio wave. No grating lobe occurs in the traveling direction 7 (direction of θ = ± 90 °).

Next, the operation will be described. The radio wave fed to the input terminal 10 of the antenna device is split by the splitter 9 into two feeding points 2a and 2b with equal amplitude. The distributed radio waves are fed from feed points 2a and 2b to feed waveguides 3a and 3b formed through holes, respectively.
After irradiating the reflecting walls 4a and 4b as cylindrical waves, they are supplied to the radiating section 6 as plane waves 12a and 12b in the traveling directions 7a and 7b of the radio waves, respectively. Here, the reflection wall 4 has a paraboloid of revolution shape, and the feeding waveguide 2 is placed at the focal point. Next, each plane wave 12a supplied to the radiation unit 6
And 12b are coupled to the respective rectangular radiation holes 5 while propagating in the traveling directions 7a and 7b of the radio waves, and are radiated as electromagnetic waves from all the rectangular radiation holes 5 to the space. Here, the traveling directions 7 a and 7 of the radio wave of each rectangular radiation hole 5 in the radiation part 6 are shown.
Since the arrangement interval S at b is smaller than λg (λg: the wavelength in the parallel plate conductor), the electromagnetic waves radiated into the space from all the rectangular radiation holes 5 are transmitted in the traveling direction 7 of the radio wave.
Is not synthesized in the normal direction perpendicular to the parallel plate, and the plane wave 12a generates the Z axis (normal direction) on the XZ plane.
Are synthesized in a direction shifted by an angle -θ from Also,
The plane wave 12b is synthesized on the XZ plane in a direction shifted from the Z axis (normal direction) by an angle + θ. Therefore, the composite wave from all the rectangular radiation holes 5 excited by the plane waves 12a and 12b is a composite beam of two beams directed at angles ± θ, and the arrangement interval S of the rectangular radiation holes 5 is λg (Λg: wavelength in a parallel plate conductor) and set to a value close to λg, each plane wave 1
Each beam formed by 2a and 12b is directed in the vicinity of the normal direction (Z axis) of the parallel plate, and the combined beam of these two beams is a front beam having a peak power in the normal direction (Z axis). Become. Since the arrangement interval of the rectangular radiation holes 5 in the traveling direction 7 of the radio wave is S ≠ λg, the plane wave 12
The reflected waves from the rectangular radiation holes 5 do not reinforce each other in phase, and the level of unnecessary beams formed by the reflected waves can be reduced. In other words, according to this antenna device, there is an effect that an antenna device having a favorable reflection characteristic of the antenna and having a radiation pattern in which a main beam is formed in the front direction without forming unnecessary beams due to reflected waves is obtained.

In addition, the rectangular radiation hole 5 in the first embodiment can be arranged so as to be inclined with respect to the traveling direction 7 of the radio wave to adjust and control the direction of the plane of polarization of the radio wave. Here, in FIG.
When the antenna device is used as an in-vehicle antenna device, when the antenna device is used as an in-vehicle antenna device, the polarization surface of the antenna that receives the reflected wave of the radio wave radiated from the own vehicle is opposed to the other device. Since the planes of polarization of the radio waves radiated from the vehicle are made to be orthogonal to each other, it is possible to obtain the effect of easily separating the reflected waves of the radio waves radiated from the own vehicle and the radio waves radiated from the transmitting antenna mounted on the opposite vehicle.

Embodiment 2 FIG. FIG. 4 is a diagram illustrating a configuration of an antenna device according to a second embodiment of the present invention. Embodiment 2 is an embodiment in which this antenna device is operated as an electronically controllable antenna capable of switching beams. As shown in FIG. 4, each of the feeding points 2a and 2b has a two-terminal switching function. The switches 13a and 13b are connected to each other, and one terminal of each of the switches 13 is connected to a common two-way distributor 9, and the other terminal and the input terminal of the two-way distributor 9 are connected to a switch 13c having a three-terminal switching function. The switch 13c is connected, and a radio wave is supplied from the input terminal 10 to the switch 13c. The front view illustrating the configuration of the antenna device according to the second embodiment is the same as that of the first embodiment.
This is the same as FIG.

The output of the switch 13c is divided into two
When the light is distributed and supplied to the feeding points 2a and 2b via the switches 13a and 13b, the plane wave 1
The front beams can be formed without the reflected waves from the two rectangular radiation holes 5 being in phase and strengthening each other. In addition, the output of the switch 13c is supplied to either the power supply point 2a or 2b via one of the switches 13a and 13b.
In this case, a −θ direction beam or a + θ direction beam directed in a symmetrical direction (angle ± θ) with respect to the Z axis can be formed. Therefore, the switch 13
By controlling the connection relationship between a, 13b, and 13c, three beams including the front beam can be electronically switched, and an effect of obtaining an electronically controlled antenna device with good reflection characteristics and beam switching can be obtained. There is.

Embodiment 3 FIG. 5 is a front view illustrating the configuration of the antenna device according to the third embodiment of the present invention.
The power supply to the power supply point 2a and the power supply point 2b is based on the configuration shown in FIG. 2 or FIG. In the third embodiment, the aperture distribution of the antenna device, particularly, the aperture distribution in the XZ plane is set to a desired arbitrary distribution. As shown in FIG.
The size of the circular radiating hole 14 is maximized on or near the center line 15 of the radiating portion 6, the shape of the circular radiating hole 14 is substantially symmetrical with respect to the center line 15,
A case will be described in which the circular radiation holes 14 are arranged so that the diameter of the circular radiation hole 14 gradually increases as approaching the center line 15.

In this case, for example, the radio wave supplied to the feeding point 2a is radiated as a cylindrical wave from the feeding waveguide 3a, converted into a plane wave 12a by the reflecting wall 4a, and converted into the center line 1 of the radiating portion 6.
Propagating towards 5. At this time, the propagating plane wave 12
The amplitude of “a” gradually decreases due to coupling to the arranged circular radiation hole 14 and dielectric loss. Therefore, when the diameter of the circular radiation hole 14 is gradually increased as approaching the center line 15 as described above, the plane wave 12a
The amplitude of the radio wave radiated by being coupled to each of the circular radiating holes 14 provided before the light is propagated can be made substantially uniform (the aperture distribution is uniform), and the angle from the Z-axis due to the arrangement interval S of the circular radiating holes 14 The gain of the beam directed by -θ becomes almost maximum. When the diameter of the circular radiation hole 14 is gradually increased toward the center line 15 by the same operation as described above for the radio wave supplied to the feeding point 2b,
The amplitude of the radio wave to be radiated by being coupled to each circular radiation hole 14 provided until the plane wave 12b propagates to the center line 15 can be made substantially uniform (the aperture distribution is approximately uniform distribution). The gain of the beam directed by the angle θ from the Z axis due to the interval S becomes almost maximum. Therefore, when power is supplied to the power supply points 2a and 2b in the configuration shown in FIG. 4 as described in the second embodiment, the power supply points 2a and 2b are symmetrical with respect to the Z axis (angle ± θ). 3) can be formed with almost the maximum gain, including the front beam, which is a combination of the beams directed to the switches 13a and 1b.
By controlling the connection relationship between 3b and 13c, three beams including these front beams can be electronically switched, and the effect of obtaining an electronically controlled antenna device with good reflection characteristics and switchable beams can be obtained. is there. In the case where power is supplied to the feeding points 2a and 2b with the configuration shown in FIG. 2 and performed as described in the first embodiment, the reflection characteristics of the antenna are set in the same manner as in the first embodiment. And an antenna device having a radiation pattern in which the main beam is formed in a state where the gain is almost maximum in the front direction without forming unnecessary beams due to reflected waves.

The reason why the gain is not completely maximized here is that even if the plane waves 12a and 12b cross the center line 15, there is a small amount of residual power, which is provided at a position beyond the center line 15. Radiated from the circular radiation hole 14,
This is because the aperture distribution is not completely uniform and the side lobe characteristics of the radiation pattern are deteriorated.

In the above description, the propagating plane wave 12
Of the radiating section 6 because the amplitude of
Above or in the vicinity, the size of the circular radiation hole 14 becomes maximum, the shape of the circular radiation hole 14 is substantially symmetrical with respect to the center line 15, and the diameter of the circular radiation hole 14 gradually increases as approaching the center line 15. Although the case where the circular radiation holes 14 are arranged as described above and the aperture distribution is made substantially uniform has been described, the present invention is not limited to this, and the increase and decrease in the diameter of the circular radiation holes 14 in the traveling direction 7 of the radio wave are appropriately set. By doing
In combination with the change in the amplitude of the propagating plane wave 12, the aperture distribution in this direction can be set to any desired distribution.

Embodiment 4 FIG. 6 is a front view illustrating the configuration of the antenna device according to the fourth embodiment of the present invention.
The power supply to the power supply point 2a and the power supply point 2b is based on the configuration shown in FIG. 2 or FIG. As shown in FIG. 6, the fourth embodiment is different from the third embodiment in that a radio wave absorber 16 is provided on the center line 15 of the radiating section 6 and in a parallel plate.

The basic operation and the effect of the fourth embodiment are the same as those of the third embodiment. However, as described in the description of the operation of the third embodiment, the plane waves 12a and 12b Even if it exceeds, there is some residual power, which is radiated from the circular radiating hole 14 provided at a position beyond the center line 15, the aperture distribution is not completely uniform, and the side lobe characteristics of the radiation pattern It is possible to eliminate the inconvenience that the gain is not completely maximized due to deterioration of the above. That is, the radio wave absorbing material 16 provided on the center line 15 of the radiating section 6 and in the parallel flat plate can consume the residual power that cannot be completely coupled to the circular radiation hole 14, so that the radiation pattern due to the residual radiation can be reduced. There is an effect that the influence can be reduced.

Embodiment 5 FIG. FIG. 7 is a front view illustrating the configuration of the antenna device according to the fifth embodiment of the present invention.
The power supply to the power supply point 2a and the power supply point 2b is based on the configuration shown in FIG. 2 or FIG. In the fifth embodiment, the aperture distribution is set to a desired arbitrary distribution even in a direction perpendicular to the traveling direction of the radio wave in the parallel flat plate. As shown in FIG. 7, for example, the shape of the circular radiation hole 14 is substantially symmetrical with respect to the center line 15, and the size of the circular radiation hole 14 becomes maximum on or near the center line 15 of the radiation part 6,
The circular radiating holes 14 are arranged so that the diameter of the circular radiating holes 14 gradually increases as approaching the center line 15, and the circular radiating holes 14 are arranged in a direction perpendicular to the radio wave traveling direction 7.
A case will be described in which the circular radiation holes 14 are arranged so that the size of the circular radiation hole 14 gradually increases as approaching the end of the parallel plate.

Here, the aperture distribution in the traveling direction of the radio wave in the parallel plate is the same as in the third embodiment.
In the direction perpendicular to the direction of propagation of the radio waves in the parallel plate, the size of the circular radiation holes 14 arranged in a row orthogonal to the direction of propagation of the radio waves 7 should be set to an appropriate value as shown in FIG. Accordingly, when the amplitude distribution of the plane wave 12 in the direction orthogonal to the traveling direction 7 of the radio wave is uniform, the aperture distribution in this direction can be an amplitude distribution based on the size distribution of the circular radiation hole 14. Further, when the amplitude distribution of the plane wave 12 in the direction orthogonal to the traveling direction 7 of the radio wave is not uniform,
By appropriately setting the increase or decrease of the diameter of the circular radiation hole 14, the aperture distribution in this direction can be made any desired distribution in combination with the amplitude distribution of the plane wave 12.
Therefore, according to the antenna apparatus of the fifth embodiment, for example, the aperture distribution in the traveling direction 7 of the radio wave is made almost uniform, and the aperture distribution in the direction orthogonal to the traveling direction 7 of the radio wave is changed to a desired distribution (uniform distribution). Distribution or an arbitrary distribution such as a Taylor distribution). In addition, the traveling direction of the radio wave 7
By appropriately setting the increase and decrease of the diameter of the circular radiation hole 14 in the above, the aperture distribution in this direction can be made a desired arbitrary distribution in combination with the change in the amplitude of the propagating plane wave 12. This is as described in the third embodiment.

Embodiment 6 FIG. FIG. 8 is a diagram illustrating the configuration of an antenna device according to Embodiment 6 of the present invention. In the figure, reference numeral 17 denotes an internal hollow conductor whose surface is formed of metal, and reference numeral 18 denotes a corrugated line in which a parallel plate internal conductor facing the arrangement surface of the rectangular radiating holes 5 of the radiating portion 6 is formed of a corrugated uneven surface conductor. . In the sixth embodiment, instead of providing a dielectric between the parallel plate conductors, a slow wave structure is formed as a corrugated line 18 inside the parallel plate conductor of the radiating section 6.

In the sixth embodiment, since the corrugated line 18 forms a slow wave structure, the propagation phase velocities of the radio waves inside and outside the parallel plates are different, and the phases of the radio waves inside and outside the parallel plates are shifted. Therefore, the traveling direction 7 (θ
(= ± 90 ° direction), no grating lobe is generated. Further, in the sixth embodiment, since a dielectric is not used to change the propagation phase speed of radio waves inside and outside the parallel plate, an efficient antenna device with no dielectric loss can be obtained.

Embodiment 7 FIG. 9 is a front view illustrating the configuration of the antenna device according to the seventh embodiment of the present invention.
The power supply to the power supply point 2a and the power supply point 2b is based on the configuration shown in FIG. 2 or FIG. In FIG. 9, 19a, 19
b denotes an oblique radiating hole, and one of the radiating holes is an oblique radiating hole 19 in which one of the radiating holes is inclined by 45 degrees with respect to the traveling direction 7 of the radio wave in the parallel flat plate.
a from the oblique radiation hole 19a in the traveling direction of the radio wave.
g / 4 (λg: wavelength in a parallel plate conductor) and the next oblique radiation hole 1
9b, a pair of circularly polarized radiation holes 20 are formed by the two oblique radiation holes 19a and 19b, and the pair of circularly polarized radiation holes 20 are arranged in the traveling direction of the radio wave. A case will be described in which a plurality of gaps are arranged so as to be smaller than λg (λg: wavelength in a parallel plate conductor) and to have a left-right mirror image relationship with the center line 15 of the radiation section 6.

In this case, the radio wave fed from the feeding point 2a is converted into a plane wave 12a by the reflection wall 4a and radiated from each circularly polarized radiation hole element 20 as a left-handed circularly polarized wave until reaching the center line 15. Further, since a plurality of circularly polarized radiation hole elements 20 are arranged so as to have a left-right mirror image relationship with respect to the center line 15 of the radiating portion 6, a circle having the same rotation as the electric wave fed from the feeding point 2b is provided. Radiated as polarized light. Here, feeding point 2
a, when power is supplied to the power supply point 2b by, for example, the configuration shown in FIG. 4 as described in the second embodiment, in this antenna apparatus, the angle direction ±± θ with respect to the Z axis (normal direction) The two beams having peaks in the first direction and the front beam having a peak in the Z-axis direction are all formed as circularly polarized beams having the same rotation, and can be electronically switched. There is an effect that a controlled circularly polarized antenna device can be obtained.

Here, in the first to seventh embodiments, the case where a part of the wall surface of the power supply waveguide 3 is formed by a plurality of through holes is shown. It may be formed by plating the surface of the groove formed by processing or the like. Further, the feeding point 2 and the feeding waveguide 3 may be an actual coaxial waveguide converter, a microstrip waveguide converter, or the like. Further, the radiation hole may have an arbitrary shape such as a circular radiation hole or a rectangular radiation hole. The radiation holes may be arranged so as to be inclined with respect to the traveling direction 7 of the radio wave, and the direction of the plane of polarization of the radio wave may be adjusted and controlled as appropriate.

[0032]

Since the present invention has the above-described structure, the following effects can be obtained.

According to the first aspect of the present invention, a plurality of radiating holes are arranged on one surface of the parallel plate conductor in a predetermined direction at an interval of λg.
(Λg: the wavelength in the parallel plate conductor), a dielectric is provided between the parallel plate conductors, and the input end of the wave source of each plane wave feeder provided at both ends of the radiator is provided. Since the two-divider is connected and power is supplied through the two-divider, an antenna device having good reflection characteristics and having a radiation pattern in which a main beam is formed in the front direction without forming unnecessary beams due to reflected waves is provided. There is an effect that can be obtained.

According to the second aspect of the present invention, a plurality of radiating holes are arranged on one side of the parallel plate conductor in a predetermined direction at an interval of λg.
(Λg: the wavelength in the parallel plate conductor), a dielectric is provided between the parallel plate conductors, and the input end of the wave source of each plane wave feeder provided at both ends of the radiator is provided. One end of a switch having a two-terminal switching function is connected to each of the switches, a two-divider is connected to one terminal of the other end of each of the switches, and the other end of each of the switches is connected to each of the other terminals. Since a switch having a three-terminal switching function capable of switching between connection with the distributor is connected and power is supplied via the switch having the three-terminal switching function, three beams including the front beam are electronically switched. Thus, there is an effect that an electronically controlled antenna device having good reflection characteristics and capable of switching beams can be obtained.

According to the third aspect of the present invention, a plurality of radiating holes are arranged on one surface of the parallel plate conductor in a predetermined direction at an interval of λg.
(Λg: wavelength in the parallel plate conductor) and the polarization directions thereof are arranged so as to be 45 degrees with respect to the above-mentioned fixed direction. Therefore, this antenna device is used as a vehicle-mounted antenna device. In this case, the polarization plane of the antenna that receives the reflected wave of the radio wave radiated from the own vehicle and the polarization plane of the radio wave radiated from the opposite vehicle are orthogonal to each other, so that an effect of being easily separated can be obtained.

According to the fourth aspect of the present invention, the radiating holes arranged on one side of the parallel plate conductor are arranged such that one of the radiating holes is inclined at an angle of 45 degrees with respect to a fixed direction. The next radiation hole whose polarization direction is orthogonal to the polarization direction of the radiation hole is arranged at a distance of λg / 4 (λg: wavelength in the parallel plate conductor) from the radiation hole in the above-mentioned fixed direction. A pair of circularly polarized radiation hole elements is formed by the two radiation holes, and the pair of circularly polarized radiation hole elements are arranged at an interval of λg (λ
g: the wavelength in the parallel plate conductor), and a plurality of the intermediate points in the certain direction are arranged so as to be in a mirror image relationship with each other, so that a circularly polarized beam having the same direction but different beam directions can be formed. There is an effect that a circularly polarized antenna device having a good reflection characteristic and a radiation pattern in which a main beam is formed in the front direction without forming unnecessary beams due to reflected waves can be obtained. Further, there is an effect that an electronically controlled circularly polarized antenna device having good reflection characteristics and capable of switching beams can be obtained.

According to the fifth aspect of the present invention, the radiation hole or the circularly polarized radiation hole element is arranged so as to be symmetrical or mirror-image at an intermediate point in a certain direction, and the amplitude change of the plane wave in the certain direction. Since the shape and size of the radiation hole are set based on the relationship described above, there is an effect that the aperture distribution in the fixed direction, which is the traveling direction of the radio wave in the parallel plate conductor, can be a desired arbitrary distribution.

According to the sixth aspect of the present invention, the radiation hole or the circularly polarized radiation hole element is arranged so as to be symmetrical or mirror-image with respect to the intermediate point in the fixed direction, and is orthogonal to the fixed direction and the fixed direction. For each of the directions, the shape and size of the radiation hole are set based on the relationship with the change in the amplitude of the plane wave. In addition, the aperture distribution in the direction orthogonal to the predetermined direction, which is the traveling direction of the radio wave in the parallel plate conductor, can be a desired distribution, and the degree of freedom of directivity synthesis in forming the radiation pattern can be increased. It has the effect of improving.

According to the seventh aspect of the present invention, the radio wave absorber is provided at an intermediate point in a certain direction between the parallel plate conductors.
Residual power that cannot be completely coupled to the radiation hole can be consumed, and there is an effect that the influence of the residual radiation on the radiation pattern can be reduced.

According to the eighth aspect of the present invention, instead of the dielectric of the radiating portion, the parallel plate conductor is provided between at least the parallel plate conductor facing the region where the radiation hole or the circularly polarized radiation hole element is provided. Since the inner conductor is arranged as a corrugated concavo-convex surface conductor in a certain direction, a grating lobe does not occur in the above-mentioned certain direction, which is the traveling direction of radio waves in the parallel plate conductor, and an efficient antenna device without dielectric loss is obtained. There is an effect that can be.

[Brief description of the drawings]

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

FIG. 2 is a block diagram illustrating a configuration of the antenna device according to the first embodiment of the present invention.

FIG. 3 is an explanatory diagram illustrating a traveling direction of a radio wave in the antenna device according to the first embodiment of the present invention.

FIG. 4 is an explanatory diagram of a configuration of an antenna device according to a second embodiment of the present invention.

FIG. 5 is a front view illustrating a configuration of an antenna device according to a third embodiment of the present invention.

FIG. 6 is a front view illustrating a configuration of an antenna device according to a fourth embodiment of the present invention.

FIG. 7 is a front view illustrating a configuration of an antenna device according to a fifth embodiment of the present invention.

FIG. 8 is an explanatory diagram illustrating a configuration of an antenna device according to a sixth embodiment of the present invention.

FIG. 9 is a front view illustrating a configuration of an antenna device according to a seventh embodiment of the present invention.

FIG. 10 is a front view illustrating the configuration of a conventional antenna device.

[Explanation of symbols]

1 Dielectric substrate whose surface is covered with a conductor, 2 Feeding point, 3
Feeding waveguide, 4 reflecting wall, 5 rectangular radiating hole, 6 radiating section, 7 traveling direction of radio wave, 8 beam direction θ, 9 2
Distributor, 10 input end, 11 plane wave feeder, 12 plane wave, 13 switch, 14 circular radiation hole, 15 center line, 16 radio wave absorbing material, 17 internal hollow conductor whose surface is made of metal, 18 corrugated line, 19 oblique radiation Hole, 20 circularly polarized radiation hole element, 21 semicircular reflector.

Claims (8)

[Claims] 1. A plurality of radiating holes are provided on one surface of a parallel plate conductor such that an arrangement interval in a certain direction is smaller than λg (λg: wavelength in the parallel plate conductor). A radiating portion in which a dielectric is provided between the parallel plate conductors facing the provided region to form a parallel plate waveguide, a reflecting wall having a paraboloid shape, and a wave source arranged at the focal point of the paraboloid And a plane wave feeder provided at each end of the radiating section for feeding a plane wave having the predetermined direction as the traveling direction to the radiating section. An antenna device, wherein the antenna device is connected, and power is supplied via the two-way splitter. 2. A plurality of radiating holes are provided on one surface of a parallel plate conductor such that an arrangement interval in a certain direction is smaller than λg (λg: wavelength in the parallel plate conductor). A radiating portion in which a dielectric is provided between the parallel plate conductors facing the provided region to form a parallel plate waveguide, a reflecting wall having a paraboloid shape, and a wave source arranged at the focal point of the paraboloid A plane wave feeder provided at both ends of the radiator to feed a plane wave having the predetermined direction as the traveling direction to the radiator, and two terminals are provided at the input terminals of the wave sources of the respective plane wave feeders. One end of a switch having a switching function is connected to each of the switches, a two-divider is connected to one terminal of the other end of each of the switches, and the other end of each of the switches is connected to each of the other terminals and the two-divider is connected. Can be switched to connection to A switch having a three-terminal switching function connected, an antenna apparatus characterized by feeding through a switch having the three-terminal switching function. 3. The antenna device according to claim 1, wherein a plurality of radiating holes are arranged on one side of the parallel plate conductor in a fixed direction and the interval between the holes is less than λg (λg: wavelength in the parallel plate conductor). And an antenna device arranged so that their polarization directions are at 45 degrees with respect to the fixed direction. 4. The antenna device according to claim 1, wherein the radiation holes arranged on one surface of the parallel plate conductor are arranged such that one of the radiation holes is polarized with respect to the predetermined direction. The polarization direction is orthogonal to the polarization direction of the radiation hole at a distance of λg / 4 (λg: wavelength in the parallel plate conductor) from the radiation hole in the predetermined direction. A radiation hole is arranged, a pair of circularly polarized radiation hole elements is formed by the two radiation holes, and the pair of circularly polarized radiation hole elements is arranged in the fixed direction at an interval of λg (λg: parallel). A plurality of antennas, each of which is arranged in a mirror image relationship with respect to the intermediate point in the above-mentioned fixed direction. 5. The antenna device according to claim 1, wherein the radiation hole or the circularly polarized radiation hole element is symmetrical or mirror-imaged with respect to an intermediate point in the fixed direction. Along with the arrangement, the shape and size of the radiation hole or the circularly polarized radiation hole element are set based on the relationship with the amplitude change of the plane wave in the fixed direction, and a desired radiation pattern is formed in the fixed direction. An antenna device characterized by the above-mentioned. 6. The antenna device according to claim 1, wherein the radiation hole or the circularly polarized radiation hole element is symmetrical or mirror-imaged with respect to an intermediate point in the fixed direction. With the arrangement, for each of the fixed direction and the direction orthogonal to the fixed direction, the shape and size of the radiation hole are set based on the relationship with the amplitude change of the plane wave, and the direction orthogonal to the fixed direction and the fixed direction. Wherein a desired radiation pattern is formed in each of the antenna devices. 7. The antenna device according to claim 5, wherein a radio wave absorber is provided at an intermediate point in the fixed direction between the parallel plate conductors. 8. The antenna device according to claim 1, wherein at least the radiation hole or the circularly polarized radiation hole element is provided instead of the dielectric of the radiation part. An antenna device, wherein an internal conductor of a parallel plate conductor is arranged as a corrugated concavo-convex surface conductor in the fixed direction between the parallel plate conductors.