JPH04207605A - Plane array antenna - Google Patents

Abstract

PURPOSE:To reduce a feeding loss of a feeder and to miniaturize and lighten the weight by forming plural slots or plural slot pairs to a ground conductor plate at prescribed intervals along the lengthwise direction of a dielectric line while being in crossing with the dielectric line. CONSTITUTION:Plural slot pairs 20 comprising a couple of rectangular slots 20a, 20b penetrating through a ground conductor plate 11 in the broadwise direction along the lengthwise direction of a dielectric line L1 are formed to the ground conductor plate 11 so that a circularly polarized electromagnetic wave radiates almost in the same phase from each slot pair 20 when a microwave propagates through the dielectric line L1 at a prescribed interval. Then a rectangular slot antenna is constructed respectively of each slot pair 20 on the dielectric line L1 used for the feeder and when a microwave is made incident in one terminal of the dielectric line L1, the microwave radiates from the other side of the ground dielectric plate 11 via each of the slots 20a, 20b and each slot pair 20. Thus, the loss of the feeder in the antenna is considerably reduced and the entire weight is made light.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a planar array antenna.

[Prior Art] FIG. 7 is a perspective view of a conventional linearly polarized planar array antenna.

In FIG. 7, rectangular microstrip batch conductors 71 and 72 are formed on a dielectric substrate 60 on which a ground conductor 61 is formed on the entire back surface, with their longitudinal directions parallel to each other. Microstrip conductor 80.8 for power supply line connected to machine (not shown)
1.82 is formed. One end of the microstrip batch conductor 71 is electrically connected to the microstrip conductor 80 via a microstrip conductor 81, and one end of the microstrip batch conductor 72 is electrically connected to the microstrip conductor 80 via a microstrip conductor 82. electrically connected.

Here, the microstrip conductor 80 and the ground conductor 61,
The microstrip conductor 81 and the ground conductor 61, and the microstrip conductor 82 and the ground conductor 61 each constitute a microstrip feed line.

[Problems to be Solved by the Invention] In the conventional planar array antenna described above, since a microstrip line is used as the feed line, the loss in the feed line is large, and as a result, the aperture efficiency of the antenna is reduced. There was a problem.

In order to solve this problem, a planar antenna has been proposed that uses a triplate line as a feed line and improves the aperture efficiency of the antenna (for example,
(See Publication No. 98202).

However, even in this planar antenna, there are still problems in that the loss in the feed line is relatively large and the aperture efficiency of the antenna is low.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and provide a planar array antenna that has a smaller feeding loss in a feeding line and can be made smaller and lighter than the conventional example.

[Means for Solving the Problems] A planar array antenna according to claim 1 of the present invention has a planar dielectric formed on one surface of a ground conductor plate, and a spiral shape formed on the other surface of the planar dielectric. A dielectric line for a feed line is formed, and a plurality of slots or a plurality of slot pairs are formed in the ground conductor plate, each with a predetermined number of slots (both of which intersect with the dielectric line and along the longitudinal direction of the dielectric line). They are formed at intervals, so that when a microwave is incident on one end of the dielectric line, it is radiated from the other surface of the ground conductor plate via each slot or each pair of slots.

The planar array antenna according to claim 2 is the planar array antenna according to claim 1, wherein a plurality of rectangular slot pairs are formed in the ground conductor plate, and two slots of each slot pair are Each of the longitudinal directions of the dielectric line is formed so as to intersect the dielectric line at different angles with respect to the longitudinal direction of the dielectric line.

Furthermore, the planar array antenna according to claim 3 is the planar array antenna according to claim 1, wherein a plurality of rectangular slots are formed in the ground conductor plate, and the longitudinal directions of the slots are parallel to each other. It is characterized by being formed as follows.

[Function] As in the planar array antenna according to claim 2, a plurality of rectangular slot pairs are formed in the ground conductor plate, and two slots of each slot pair have their respective longitudinal directions aligned with the dielectric material. When formed so as to intersect with the dielectric line at mutually different angles with respect to the longitudinal direction of the line, each of the slot pairs constitutes a circularly polarized slot antenna.

Here, when a microwave is incident on one end of the dielectric line, for example, from a rectangular waveguide as is known through a horn,
The microwave propagates through the dielectric line, and the microwave electromagnetic waves propagating through the dielectric line are transmitted from each circularly polarized slot antenna composed of a slot pair to the surface of the ground conductor plate. It is radiated with circular polarization in the perpendicular direction.

In other words, when the microwave propagates through the dielectric line, each electromagnetic wave corresponding to a portion of its power is radiated from each circularly polarized slot antenna, and when the entire planar array antenna is viewed, the interval between each slot is If selected appropriately, the circularly polarized electromagnetic waves radiated from the plurality of circularly polarized slot antennas are combined and radiated with substantially the same phase.

Further, as in the planar array antenna according to claim 3, a plurality of rectangular slots are formed in the ground conductor plate,
When the respective slots are formed so that their longitudinal directions are parallel to each other, each of the slots constitutes a linearly polarized slot antenna.

Here, when a microwave is incident on one end of the dielectric line, for example, from a rectangular waveguide as is known through a horn,
The microwave propagates through the dielectric line, and the microwave electromagnetic waves propagating through the dielectric line are transmitted from each linearly polarized slot antenna composed of slots to the surface of the ground conductor plate. It is radiated with linear polarization in the vertical direction.

In other words, when the microwave propagates through the dielectric line, each electromagnetic wave corresponding to a portion of its power is radiated from each linearly polarized slot antenna, and when the entire planar array antenna is viewed, the interval between each slot is If is appropriately selected, the linearly polarized electromagnetic waves radiated from the plurality of linearly polarized slot antennas are combined and radiated in substantially the same phase.

In the planar array antenna according to claim 1, 2 or 3, a dielectric line for feeding line for feeding microwaves to each slot antenna is formed directly under each slot antenna, and the microwave is transmitted to the dielectric line. Since the electromagnetic waves are radiated from each slot antenna while being propagated through the line, the loss of the feed line in the antenna can be significantly reduced compared to the conventional example, and this allows the aperture of the planar array antenna to be reduced. The efficiency can be significantly improved and the gain can be high.

In addition, since the ground conductor plate forming the plurality of slots or the plurality of slot pairs is formed on a planar dielectric material, it can be made thin by plating method and photolithography method, and the planar array The weight of the antenna can be reduced.

[Example] Hereinafter, an example according to the present invention will be described with reference to the drawings.

First Embodiment FIGS. 1, 2 and 3 show a circularly polarized plane array antenna which is a first embodiment of the present invention.

The planar array antenna of this first embodiment has two
The present invention is characterized in that a plurality of circularly polarized slot antennas constituted by slot pairs 20 of slots 20a and 20b are formed on a dielectric feed line Ll formed in a circular spiral shape.

As shown in FIGS. 2 and 3, a base portion 10b having a predetermined thickness t and a predetermined thickness t2 larger than the base portion 10b are provided on the back surface of the disc-shaped ground conductor plate 11. Width W
A dielectric IO made of dielectric ceramics, for example, is formed. Here, as shown in FIG. 1, the ridge portion 10a is formed in a circular spiral shape except for the input end T1 of the dielectric line L1 located at the outer peripheral edge of the ground conductor plate 11, and an end portion T1 and a termination portion T located near the center of the ground conductor plate 11;
A ridge-type dielectric line L1 having 2 is formed.

Furthermore, the ridge portion 10a has a thickness t2 that is sufficiently larger than the thickness tl of the base portion 10b so that when a microwave is incident on the input end T1, the microwave propagates only through the ridge portion 10a. It is formed to have. Note that in FIG. 1, a portion of the ridge-type dielectric line L1 constituted by the ridge portion 10a of the dielectric 10 is shown by a dotted line for convenience.
Also in FIGS. 4 to 6 below, the portion of the ridge-type dielectric line L1 or L2 is illustrated by a dotted line.

Further, directly below the dielectric 10 and facing the dielectric 10,
A disk-shaped ground conductor plate 12 is formed, and furthermore, both liquid ground conductor plates 11 are located at the outer peripheral edge of the ground conductor plate 11.12.
．． A cylindrical ground conductor plate 13 for holding the ground conductor plates 11 and 12 facing each other at a predetermined interval of nine is connected to the inner side of the ground conductor plates 12 by, for example, soldering. In addition,
The ground conductor plates 11, 12, 13 are preferably made of Cu.

Each of the ground conductor plates 11 is provided with a line extending through the ground conductor plate 11 in the thickness direction along the longitudinal direction of the dielectric line L1.
A pair of rectangular slots 20a.

A plurality of slot pairs 20 consisting of 2Qb are arranged at predetermined intervals, and circularly polarized electromagnetic waves are radiated from each slot pair 20 in substantially the same phase when the microwave propagates to the dielectric line L1. is formed. That is, in each slot pair 20, slot 20a and slot 20b
are formed close to each other, and the longitudinal side of the slot 20a is the left edge of the dielectric line L1 in the width direction (hereinafter referred to as (referred to as one edge of the dielectric line L1)
At the same time, the longitudinal direction of the slot 20a is rotated by a predetermined acute angle θ clockwise from the tangent to the line at one edge of the dielectric line L1 when viewed from above the planar array antenna. It is formed in such a way that it is oriented in the same direction as the slot.

The longitudinal side of the line 20b is the dielectric line L1 when viewed in the direction of propagation of the transmitting microwave in FIG.
The slot 20 intersects with the right edge in the width direction (hereinafter referred to as the other edge of the dielectric line L1).
The longitudinal direction of b is a direction rotated counterclockwise by a predetermined acute angle θ2 from the tangent to the line at the other edge of the dielectric line L1 when viewed from above the planar array antenna. Ru.

According to the inventor's experiments, the spacing between the slot pairs 20 is preferably set in the range from 0.3λg to λg, where λ is the distance between the slot pairs 20 and λg, where λ is the distance between the slot pairs 20 and λg. This is the internal wavelength of microwaves.

Furthermore, a cross-shaped slot 21 passing through the ground conductor plate 11 in the thickness direction is formed in the vicinity of the terminal end T2 of the dielectric line L1 and approximately at the center of the ground conductor plate 11.

In the circularly polarized planar array antenna of the first embodiment configured as described above, each slot pair is formed on the dielectric line L1 used as a feed line along the longitudinal direction of the dielectric line L1. 20 constitute a rectangular slot antenna, and the plurality of rectangular slot antennas constitute a rectangular slot array antenna.

Input end T of dielectric line L1 of the planar array antenna
1, for example, when a microwave is incident from a rectangular waveguide through a horn as is well known, the microwave propagates through a dielectric line L1 constituted by a ridge portion 10a of a dielectric 10 and reaches a terminal portion T2. reach Microwave electromagnetic waves propagating through this dielectric line L1 are transmitted from each rectangular slot antenna constituted by a pair of slots 20 to a ground conductor plate 1.
It is radiated with circular polarization in the direction indicated by the arrow Ao in FIGS. 1 and 2, which is perpendicular to the plane of FIG. That is, when a microwave propagates through the dielectric line L1, each electromagnetic wave corresponding to a part of its power is radiated from each rectangular slot antenna. The emitted circularly polarized electromagnetic waves are synthesized in substantially the same phase as shown by arrow A.
.

radiated in the direction of

In the circularly polarized planar array antenna of the first embodiment configured as described above, a dielectric line L1 for feeding microwaves to each rectangular slot antenna is formed directly under each rectangular slot antenna, and Since the microwave is propagated through the dielectric line L1 and the electromagnetic waves are radiated from each of the rectangular slot antennas, the loss of the feed line in the antenna can be significantly reduced compared to the conventional example. , it is possible to significantly improve the aperture efficiency of the planar array antenna and increase its gain.Also, since the ground conductor plate forming the slot is formed on a planar dielectric material, the plating method Because it can be made thin using photolithography methods,
The overall weight of the planar array antenna can be reduced.

In the first embodiment, the dielectric line L1 is formed in a circular spiral shape, but the present invention is not limited to this, and as shown in FIG. The dielectric line L2 may be formed in a rectangular spiral shape. In the modification shown in FIG. 5, a plurality of slot pairs 40 consisting of a pair of rectangular slots 40a and 40b are formed in a rectangular plate-shaped ground conductor plate 11a along the longitudinal direction of the dielectric line L2. and are formed so that when the microwave propagates in the dielectric line L2, the electromagnetic waves are radiated from each slot pair 40 in substantially the same phase,
Further, a cross-shaped slot 41 is formed in the ground conductor plate 11a in the vicinity of the terminal end T12 of the dielectric line L2 and approximately at the center of the ground conductor plate 11a.

Second Embodiment FIG. 4 is a plan view of a linearly polarized planar array antenna according to a second embodiment of the present invention. Components in FIG. 4 that are similar to those in FIG. are doing.

The planar array antenna of this second embodiment has one
The present invention is characterized in that a plurality of linearly polarized slot antennas constituted by slots 30 are formed on a dielectric feed line L1 formed in a circular spiral shape. below,
Differences from the first embodiment will be explained.

In FIG. 4, a plurality of rectangular slots 30 are formed in the ground conductor plate 11 along the longitudinal direction of the dielectric line L1.
They are formed at predetermined intervals so that when the microwave propagates through the dielectric line L1, linearly polarized electromagnetic waves are radiated from each slot 30 in substantially the same phase. That is, each slot 30 has its longitudinal side intersecting one or the other edge of the dielectric line L1, and
The longitudinal sides of each slot 30 are parallel to each other. According to the inventor's experiments, the interval between the slots 30 is preferably 0°3λg to λ
It is set in the range up to g.

Furthermore, in the vicinity of the terminal end T2 of the dielectric line L1 and approximately at the center of the ground conductor plate 11, there is a rectangular slot 31 that penetrates the ground conductor plate 11 in the thickness direction. It is formed parallel to the longitudinal direction of the slot 30.

In the linearly polarized planar array antenna of the second embodiment configured as described above, each slot 20 is formed on the dielectric line L1 used as a feed line along the longitudinal direction of the dielectric line L1. Each of these rectangular slot antennas constitutes a rectangular slot antenna, and the plurality of rectangular slot antennas constitute a rectangular slot array antenna.

Input end T of dielectric line L1 of the planar array antenna
1, for example, when a microwave is incident from a rectangular waveguide through a horn as is well known, the microwave propagates through a dielectric line L1 constituted by a ridge portion 10a of a dielectric 10 and reaches a terminal portion T2. reach Microwave electromagnetic waves propagating through this dielectric line L1 are transmitted from each rectangular slot antenna formed of slots 30 to a ground conductor plate 11.
4, perpendicular to the plane of arrow A in FIG. It is radiated with linear polarization in the direction shown by . That is, when a microwave propagates through the dielectric line L1, each electromagnetic wave corresponding to a part of its power is radiated from each rectangular slot antenna. The radiated linearly polarized electromagnetic waves are combined in substantially the same phase and radiated in the direction of arrow A.

In the linearly polarized planar array antenna of the second embodiment configured as described above, similarly to the first embodiment, the dielectric line L1 for feeding microwaves to each rectangular slot antenna is connected to each rectangular slot antenna. Formed directly under the slot antenna,
Since the microwave is propagated through the dielectric line L1 and the electromagnetic waves are radiated from each of the rectangular slot antennas, the loss of the feed line in the antenna can be significantly reduced compared to the conventional example. This greatly improves the aperture efficiency of the planar array antenna,
The gain can be increased. Furthermore, since the ground conductor plate that forms the slot is formed on a planar dielectric material, it can be made thinner by plating and photolithography methods, reducing the overall weight of the planar array antenna. .

In the second embodiment, the dielectric line L1 is formed in a circular spiral shape, but the present invention is not limited to this, and as shown in FIG. The dielectric line L2 may be formed in a rectangular spiral shape. In the modified example shown in FIG. 6, a plurality of slots 50 are provided at predetermined intervals along the longitudinal direction of the dielectric line L2 in the rectangular plate-shaped ground conductor plate 11a, and the microwave The electromagnetic waves are formed so as to be radiated from each slot 50 in substantially the same phase when propagating,
Further, in the vicinity of the terminal end T12 of the dielectric line L2 and approximately at the center of the ground conductor plate 11a, a square slot 51 is formed in the ground conductor plate 11a, and the two opposing sides thereof correspond to the longitudinal direction of the slot 50. They are formed parallel to each other.

Other Embodiments In each of the above embodiments, the ridge-type dielectric line L1 or L2 formed of the same dielectric material is used as the feed line, but as shown in FIG. 10b have mutually different relative dielectric constants ε1. It may be formed of a different dielectric material having ε2.

[Effects of the Invention] As detailed above, according to the present invention, a planar dielectric is formed on one surface of the ground conductor plate, and a feed line dielectric is formed in a spiral shape on the other surface of the planar dielectric. A track is formed, a plurality of slots or a plurality of slot pairs in the ground conductor plate,
Each of the slots or each pair of slots are formed at predetermined intervals along the longitudinal direction of the dielectric line so as to intersect at least the dielectric line, and when microwaves are incident on one end of the dielectric line, It is characterized in that the radiation is radiated from the other surface of the ground conductor plate via the ground conductor plate.

Therefore, a feed line dielectric line for feeding microwaves to each slot antenna constituted by each slot or each slot pair is formed directly under each slot antenna, and the microwave is propagated to the dielectric line. Since the electromagnetic waves are radiated from each of the above-mentioned slot antennas, the loss of the feed line in the antenna can be significantly reduced compared to the conventional example.
There is an advantage that the aperture efficiency of the planar array antenna can be greatly improved and its gain can be increased.

Furthermore, since the ground conductor plate forming the plurality of slots or the plurality of slot pairs is formed on the planar dielectric material,
It has the advantage that it can be made thinner by using the plating method, photolithography method, etc., and the weight of the entire planar array antenna can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a circularly polarized planar array antenna according to a first embodiment of the present invention, FIG. 2 is a vertical cross-sectional view taken along line nn' in FIG. 1, and FIG. 4 is a plan view of a linearly polarized plane array antenna according to a second embodiment of the present invention; FIG. FIG. 6 is a plan view of a linearly polarized planar array antenna which is a modification of the second embodiment of the present invention, and FIG. 7 is a conventional example. FIG. 8 is a sectional view of a circularly polarized planar array antenna which is a modification of the first embodiment. 10... Dielectric, 11, Ila, 12... Ground conductor plate, 20a, 20b
, 30, 40a, 40b, 50...Slot, 20.40...Slot pair, Ll, L2...Dielectric feed line. Patent applicant: Murata Manufacturing Co., Ltd. Representative: Patent attorney: 1 person, Ao-Haku, Ao-Haka (Fig. 4-1 No) Fig. 7 Fig. 8

Claims (3)

[Claims] (1) A planar dielectric is formed on one side of the ground conductor plate,
A dielectric line for a feed line is formed in a spiral shape on the other surface of the planar dielectric, and a plurality of slots or a plurality of slot pairs are formed in the ground conductor plate, each intersecting at least the dielectric line, and Formed at predetermined intervals along the longitudinal direction of the body line, when microwaves are incident on one end of the dielectric line, from the other surface of the ground conductor plate through each of the slots or each pair of slots. A planar array antenna characterized by radiation. (2) A plurality of rectangular slot pairs are formed in the ground conductor plate, and the two slots of each slot pair are arranged such that their respective longitudinal directions are at mutually different angles with respect to the longitudinal direction of the dielectric line. 2. The planar array antenna according to claim 1, wherein the antenna is formed to intersect with the dielectric line. (3) The planar array antenna according to claim 1, wherein a plurality of rectangular slots are formed in the ground conductor plate, and each of the slots is formed so that its longitudinal direction is parallel to each other.