JPH0720014B2 - Planar array antenna - Google Patents

Description

TECHNICAL FIELD The present invention relates to a planar array antenna that can be used as an antenna for dual orthogonal polarization and dual frequency sharing.

[Prior Art] Conventionally, as a planar antenna of this type, there is an array antenna in which microstrip patch antennas are arranged on a printed board as shown in FIG. That is, this array antenna is a microstrip patch antenna.
11 are arranged in a plane on the upper surface of the layer of the dielectric 13 on the ground plate 12 made of a conductor, and each microstrip patch antenna 11 has a predetermined beam so as to form a sharp beam in a desired direction. The microstrip line 14 for giving the excitation amplitude and the phase is in contact with each other.

[Problems to be Solved by the Invention] However, the above-described conventional antenna is an array of microstrip patch antennas for single-point feeding, and has the following problems.

Two orthogonal polarizations cannot be transmitted or received.

The microstrip patch antenna used as a radiating element has a very narrow frequency bandwidth.

From the above, communication of orthogonal polarized waves at two frequencies apart from each other cannot be performed.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a planar array antenna that has a size of one antenna and can be used as an antenna for dual polarization and two frequencies.

[Means for Solving the Problems] In order to achieve the above object, a planar array antenna according to the present invention is configured such that an intermediate conductor plate is sandwiched between an upper dielectric plate and a lower dielectric plate, and an upper conductor surface and a lower part are provided on an upper surface of the upper dielectric plate. A lower conductor surface is provided on the lower surface of the dielectric plate to form a tri-plate substrate, and the first conductor and the second slot, which have different resonant frequencies, are formed in the middle conductor plate of the tri-plate substrate by 90 degrees. A plurality of microstrip lines are arranged on the upper conductor surface in independent directions without contact with each other, and a first microstrip line for supplying electric power to the first slot to excite the first slot is provided in the longitudinal direction of the first slot. And a second microstrip line for exciting the second slot by feeding power to the second slot on the lower conductor surface. Hand direction and 90
The first microstrip line and the second microstrip line are arranged linearly in different directions, and are arranged so as to face different directions by 90 degrees.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 (a) is an overall perspective view of an embodiment of the present invention, and FIG. 1 (b) is an enlarged partial cutaway view of a main part of FIG. 1 (a).

In these drawings, 1 is an intermediate conductor plate, which is sandwiched between an upper dielectric plate 4 and a lower dielectric plate 5. Although not shown, thin upper conductor surfaces and lower conductor surfaces are formed on the upper surface of the upper dielectric plate 4 and the lower surface of the lower dielectric plate 5, respectively.
The intermediate conductor plate 1, the upper dielectric plate 4, the lower dielectric plate 5, and the upper conductor surface and the lower conductor surface constitute a tri-plate substrate having three conductor surfaces.

The intermediate conductor plate 1 of the tri-plate substrate has a slotted first slot 2 and a second slot 3 having different resonance frequencies.
However, a plurality of them are arranged so that their angles are different from each other by 90 degrees and that they do not contact each other.

In addition, the first slot 2 is formed on the upper conductor surface of the upper dielectric plate 4.
A first microstrip line 6 is provided linearly in a direction different from the longitudinal direction of the first slot 2 by 90 degrees and is electromagnetically coupled to the first slot 2. Further, a second microstrip line 7 is linearly provided on the lower conductor surface of the lower dielectric plate 5 in a direction different from the longitudinal direction of the first slot 3 by 90 degrees, and is electromagnetically coupled to the second slot 3. Are doing

Furthermore, the first microstrip line 6 and the second microstrip line 7 are arranged so as to face different directions by 90 degrees.

Therefore, the first microstrip line 6 acts as a feeder for exciting the first slot 2 and the second microstrip line 7 excites the second slot 3 at a desired frequency.

As described above, in the antenna of the above-described embodiment, the first microstrip line 6 and the second microstrip line 7 are used as the power supply lines, and the first slot row 2 on the intermediate conductor plate 1 is used.
Also, the second slot row 3 is separately excited from the front surface and the back surface, and operates as a planar antenna that radiates radio waves of orthogonal polarized waves of different frequencies. At this time, since the power supply lines of the two frequencies are separated into the front and back of the intermediate conductor plate 1, there is almost no electrical coupling between the power supply lines and it can be ignored.

Reference numeral 8 denotes a reflector, which is located below the lower dielectric plate 5 and which is the intermediate conductor plate 1.
It is arranged in parallel with. The reflector 8 reflects downwardly radiated components of the radio waves radiated from the first and second slots and re-radiates upwardly. Due to the presence of the reflector 8, the gain of the present antenna is approximately doubled. In addition,
The distance between the reflection plate 8 and the conductor plate 1 is about 1 / the operating frequency.
At four wavelengths or an odd multiple of that, the gain is almost maximum.

FIG. 2 shows an example of actual measurement data in the above embodiment. The actual measurement conditions are as follows.

First slot 2 fed to upper first stripline 5: resonance frequency 11.95 GHz Number of elements 8 rows x 12 elements = 96 elements Second slot 3 fed to second lower stripline 6 3: resonance frequency 14.25 Number of GHz elements 10 rows x 11 elements = 110 elements Fig. 2 (a) shows the radiation pattern at 11.95 GHz, and Fig. 2 (b).
Shows the radiation pattern at 14.25 GHz, and the same figure (C) shows the amount of coupling between the two power supply lines. The terminals in the 14 GHz band range from 13.8 GHz to 14.6 GHz.
It was observed by applying a high frequency voltage of GHz and how much was generated at the terminals in the 12 GHz band, and it can be seen that the coupling degree is low around -40 dB.

Further, the present antenna can be designed as follows. That is, when the installation location of the main antenna of the communication partner is known in advance, the beam tilt design can be performed so that the beam direction of the main antenna faces the communication partner direction at the time of designing. This beam tilt is so that the feeding electric field phase to each slot is aligned in the direction you want to tilt the beam,
The distance between the first and second microstrip lines or the distance between the first and second slots may be set.

As described above, in the planar array antenna described above, of the three conductor layers of the tri-plate substrate, the first and second slots having two different resonance frequencies are perpendicular to and non-contact with the intermediate conductor plate. Independently, and on the first and second conductor surfaces, the first and second microstrip lines are provided at right angles and linearly with respect to the corresponding first and second slots, respectively, and By arranging the first and second microstrip lines at right angles, the functions of two antennas having different frequencies and orthogonal polarizations can be contained in one plane of the size of one antenna. it can.

As a result, the weight of the antenna becomes extremely light as compared with a parabolic antenna or the like. Further, the beam tilt design can be easily performed.

EFFECTS OF THE INVENTION As described above, according to the planar array antenna of the present invention, the size of one antenna and the orthogonal polarization
There is an effect that a plane antenna for two frequencies can be obtained.

[Brief description of drawings]

FIG. 1 (a) is an overall perspective view of an embodiment of the present invention, FIG. 1 (b) is an enlarged partial cutaway view of an essential part of FIG. 1 (a), and FIGS. 2 (a) to (c) are FIG. 3 shows an example of actual measurement data of the embodiment, and an overall perspective view of the conventional example. 1: Intermediate conductor plate 2: First slot 3: Second slot 4: Upper dielectric plate 5: Lower dielectric plate 6: First microstrip line 7: Second microstrip line 8: Reflector plate

Claims (1)

[Claims] 1. A tri-plate substrate is formed by sandwiching an intermediate conductor plate between an upper dielectric plate and a lower dielectric plate, further providing an upper conductor surface on the upper surface of the upper dielectric plate and a lower conductor surface on the lower surface of the lower dielectric plate, On the intermediate conductor plate of this tri-plate substrate, a plurality of slot-shaped first slots and second slots having different resonance frequencies are arranged in different directions by 90 degrees and in an independent state without contacting each other. On the conductor surface, a first microstrip line for feeding and exciting the first slot is provided linearly in a direction different from the longitudinal direction of the first slot by 90 degrees, and on the lower conductor surface. A second microstrip line for feeding and exciting the second slot is provided linearly in a direction different from the longitudinal direction of the second slot by 90 degrees; A planar array antenna characterized in that the lip line and the second microstrip line are arranged so as to face in directions different by 90 degrees.