JPH0382205A - Microstrip patch antenna with slot plate - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a microstrip patch antenna used for microwaves.

(Prior Art) Currently, there are parabolic antennas and various planar antennas as antennas for the microwave band.Especially since the start of satellite broadcasting, planar antennas that are easy to handle have been attracting attention.

Various types of planar antennas have been researched and developed, including microstrip, radial line, triplate, and susbenzoid line antennas. Among these, the antenna using microstrip is shown in Fig. 9(a).
And as shown in (b), a ground conductor 2 is provided on one surface of the dielectric 3, and a plurality of radiating elements 4 and feed lines 5 are provided on the other surface, and the ground conductor 2 is provided on the other surface, and the ground conductor 2 is provided on the side of the radiating element 4 at regular intervals. An antenna is known in which a metal plate 7 is disposed, and a slot 6 passing through the metal plate 7 is provided at a location of the metal plate 7 corresponding to the radiating element 4.

(Problems to be Solved by the Invention) Conventional microstrip antennas with slots are thin, lightweight, and easy to manufacture, but have a gain of 30 dB.
If the above is attempted, the number of punches serving as radiating elements must be increased, resulting in an increase in loss caused by the feeder line, resulting in a decrease in efficiency.

That is, as shown in a conventional example in FIG. 9, the gain of an antenna in which a radiating element 4 is provided on the side where the ground conductor 2 is not provided on a dielectric 3 provided with a ground conductor 2, and slots 6 are provided at regular intervals is as follows. , as shown in FIG. 10, is determined by the relative permittivity of the dielectric 3, and is at most 10 dB or less. Therefore, in order to obtain an antenna with a gain of 30 dB, 500 to 1000 such antennas must be arranged and connected. When such a large number of antennas are arranged, if the spacing between the radiating elements 4 is increased, the antenna Power supply by increasing the area required as! ! ? The length of t5 becomes longer and the loss becomes larger. Furthermore, if the spacing between the radiating elements 4 is made smaller, the electrical coupling between the feeder line 5 and the radiating elements 4 and between the radiating elements 4 becomes stronger and the gain decreases.
Even if the arrangement of the radiating elements 4 is devised, it is difficult to achieve an efficiency of 90% or more when loss in the feeder line 5 is not considered.

The present invention provides a microstrip antenna with excellent radiation gain and excellent suppression of loss in the feeder line.

(Means for Solving the Problems) The microstrip antenna of the present invention includes a metal plate 7 having a plurality of slots 6, a plurality of radiating elements 4, a ground conductor 2, and a feed line 5. A grounding conductor 2 is arranged at a fixed interval from the ground conductor 2, and a metal plate 7 is arranged at a fixed interval on the side without the grounding conductor 2, and the number of slots 6 provided in the metal plate 7 is determined by the number of slots 6 provided in the metal plate 7. The special radiating elements 4, which are characterized by being larger in number than the number of elements 4, may be provided on one surface of the dielectric material 3 other than air, as shown in FIG.
As shown in FIG. 1, a part of the dielectric 3 may be made into an air layer, or as shown in FIG. A film-like material can also be used as the dielectric material 3 other than the above.

Further, the ground conductor 2 can also be provided on one surface of the dielectric 3 other than air, similarly to the radiating element 4. gold ri
The S temporary 7 can be formed by forming a metal layer 9 on a dielectric 8 as shown in FIG. 1 (f), (g) or (hH), and the slot 6 can be formed as shown in FIG. It may also be a hole penetrating the laminate as shown in Figure 1Cf).
, (h), it is also possible to form a metal-free portion 10 in the metal layer 9 by etching or the like. Furthermore, the metal layer 9 can be formed on both sides of the dielectric 8 as shown in FIG. 1(h).

As for the material of the dielectric 3 used in the present invention, an insulating material with a small dielectric loss tangent and a small dielectric constant can be used, and the radiating element 4 and the ground conductor 2 do not necessarily need to be fixed by adhesive, but they can be laminated to adjust their thickness. Preferably, the shape does not change. As such a dielectric material, an organic insulating material is particularly preferable, and a foam containing air inside can also be used.
It is also possible to use spacers to support the radiating element 4 and the ground conductor 2, and to use air as the dielectric 3.

Any metal conductor can be used as the ground conductor 2, and any thickness can be used as long as it can be manufactured using current technology. That is,
If a film-like material is used as the organic insulating material listed as the dielectric material 3, an extremely thin metal layer can be formed on its surface using techniques such as sputtering or vapor deposition.
Further, a metal foil formed by rolling or electroplating may be bonded together, or a metal plate may also be used. In addition, the material is aluminum,
Iron, copper, nickel or alloys with these and other metals are used and these i! The design is based on economy, weight and required mechanical and electrical properties.

The radiating element 4 and the feed line 5 can be made of the same material as the ground conductor described above, and their shape can be processed by selectively etching and removing the metal foil that has been bonded to the dielectric 3 in advance. -II methods of manufacturing wiring boards, such as forming the necessary conductors by electroless plating, using a combination of both, or forming the necessary conductors in paste form by silk printing. method can be used.

The metal plate 7 can be made of the same material as the grounding conductor 2, the radiating element 4, and the feeder line 5, and the slot 6 formed in the metal plate 7 is used to connect the radiating element 4 and the feeder line 5.
Similar to the method for forming A5, general wiring board manufacturing methods can be used, and methods used for sheet metal processing for boat fishing, such as press punching, etching, and laser processing, can also be used. .

The number of slots 6 provided in this metal plate 7 must be greater than the number of radiating elements 4.

Furthermore, the slots 6 may be arranged in locations that do not all correspond to the radiating elements 4 on the metal plate 7, as shown in FIG. like,
A portion can also be provided at a location corresponding to the radiating element 4. In either of the above cases, it is preferable to arrange point-symmetrically with respect to the location corresponding to the radiating element 4 on the metal plate 7, and more preferably on the same circle.

The shape of this slot 6 may be any shape, such as circular, square, cross, or It can also be used for things.

A certain number of such slots 6 are combined with one radiating element 4 to form one group of antenna elements, and a plurality of antenna groups are arranged to form one planar antenna. If the slots 6 are shared, the area of the antenna can be used effectively.As a preferable example, the slots 6 are provided only at locations that do not correspond to the radiating elements 4, as shown in FIG. 4(a). FIG. 4(b) and FIG. 5 show slots 6 also provided at the locations where the slots 6 are provided.

(Function) As a result of intensive study, the inventors of the present invention found that a slot 6 is located at a location that does not correspond to one radiating element 4, as shown in FIG.
If the radiation element 4 is provided, the gain is improved.
It has been found that the slot 6 may be provided at a location corresponding to . The microstrip antenna of the present invention is based on this knowledge. The reason for this is that the radio waves radiated from one radiating element 4 are dispersed into each of the plurality of slots 6 provided in the metal plate 7 and radiated into space, so the beam width is narrowed and the gain is improved. .

Example 1 The structure was as shown in FIGS. 1(a) and (b), and the thickness was 1 mm.
aluminum plate with a dielectric constant of 1.77 and a thickness of 0.8
The copper foil of a laminated plate made by laminating a 35 μm thick rolled copper foil and a 35 μm thick rolled polyethylene sheet is etched to form a patch-type radiating element and a power supply line. An X-shaped slot is placed between the radiating element 1 and the 8 mm thick foam with a dielectric constant of approximately 1.
Aluminum plates with a thickness of 0.5 mm were stacked to form a microstrip antenna. At this time, the slots are a combination of slots with a diameter of 3 mm and a length of 12°5 mm in an X shape, and one slot is placed at a location corresponding to the radiating element.
Four pieces were provided at equal intervals on the same circle with a circumferential radius of 14 mm.

Example 2 The structure was as shown in Fig. 2 (a) and (b), and the thickness was 1 mm.
aluminum plate with a dielectric constant of 1.77 and a thickness of 0.8
The copper foil of a laminated plate made by laminating a 35 μm thick rolled copper foil and a 35 μm thick rolled polyethylene sheet is etched to form a patch-type radiating element and a power supply line. An 8 mm thick foam with a dielectric constant of approximately 1 is sandwiched between the X-shaped slots and the radiating element l.
Aluminum plates with a thickness of 0.5 mm were stacked to form a microstrip antenna. At this time, the slot is a combination of slots with a width of 3 mm and a length of 12.5 mm in an X shape, and one slot is placed at a location corresponding to the radiating element.
Eight pieces were provided at equal intervals on the same circle with a circumferential radius of 14 mm.

Example 3 The same as Example 1 was used except that one slot was provided at a location corresponding to the radiating element, and eight slots were provided at equal intervals on the same circle with a circumferential radius of 16 mm.

Example 4 The same as Example 1 except that one slot was provided at a location corresponding to the radiating element and eight slots were provided at equal intervals on the same circle with a circumferential radius of 18 mm.

Example 5 The same as Example 1 except that one slot was provided at a location corresponding to the radiating element, and eight slots were provided at equal intervals on the same circle with a circumferential radius of 20 mm.

Example 6 It was the same as Example 2 except that the configuration was as shown in FIGS. 3(a) and 3(b).

Example 7 The structure was the same as in Example 3 except that the configuration was as shown in FIGS. 3(a) and 3(b).

The structure was the same as in Example 4, except that the structure of the example was shown in FIGS. 3(a) and 3(b).

Example 9 It was the same as Example 5 except that the configuration was as shown in FIGS. 3(a) and 3(b).

Example 1 '0 Example 1 except that the configuration was the same as that shown in FIGS. 1(b) and (c), and a spacer with a thickness of 8 mm was used instead of the 8-thick foam.
The same is true.

Example 11 The configuration was as shown in FIGS. 1(b) and (d), except that the radiating element closer to the metal plate 7 was used as a parasitic element, and the feed line 4 was connected to the radiating element closer to the ground conductor 2. The procedure was the same as in Example 10.

Example 12 The configuration was as shown in FIGS. 1(b) and (e), except that the feeding of the radiating element closer to the metal plate 7 and the radiating element closer to the ground conductor 2 were made to have a 90° phase difference. The procedure was the same as in Example 10.

Example 13 The structure was as shown in FIGS. 1(b) and 1(f), and the dielectric material was a substrate with a dielectric constant of 1.77 and a thickness of 0.8 mm, similar to the substrate on which the radiating element used in Example 1 was formed. Example 1 was performed, except that the copper foil of a laminate made by laminating a foamed polyethylene sheet and a rolled copper foil with a thickness of 35 μm was etched to form a portion without SR foil in a shape corresponding to the slot 6. The same was true.

Example 14 The structure is as shown in FIGS. 1(b) and 1(g), and y is the body. Similar to the substrate on which the radiating element used in Example 1 was formed, the dielectric constant was 1.77 and the thickness was 0. Example 1O except that w4Vi, which is a laminate made by laminating an 8 mm foamed polyethylene sheet and a 35 μm thick rolled copper foil, was etched to form a portion without copper foil in a shape corresponding to the slot 6. The same is true.

Example 15 The structure was as shown in FIGS. 1(b) and 1(h), and the dielectric material was a substrate having a dielectric constant of 1.77 and a thickness of 0.8 mm, similar to the substrate on which the radiating element used in Example 1 was formed. Example 11 except that the copper foil of a laminate made of a polyethylene foam sheet and a rolled copper foil with a thickness of 35 μm was etched to form a portion without copper foil in the shape corresponding to the slot 6. The same was true.

Embodiment 16 As shown in FIG. 4(b), the number of radiating elements is 256, one slot 6 is shared with each of the four adjacent antenna elements, and the configuration is the same as in Embodiment 1, as shown in FIG. (a) and (b).

Embodiment 17 As shown in FIG. 5, Embodiment 5 is implemented except that four of the configurations shown in FIG. 3 are collected, and the slots corresponding to one radiating element share two slots corresponding to other radiating elements. The same is true.

Comparative example The configuration was the same as in Example 2 except for the configuration shown in FIG.

In both the above examples and comparative examples, the frequency is 120) 4 z
The characteristics were investigated.

The radiation characteristics of Example 10 are shown in FIG. 6(a), the frequency characteristics are shown in FIG. 6(b), and the radiation characteristics of Comparative Example are shown in FIG. 7. As a result, the gain of Example 1 was approximately 4
It can be seen that there is a dB improvement.

In addition, the gain of the antennas of Examples 2 to 9 was changed to a frequency of 12G.
As a result of measurement at Hz, as shown in FIG. 8, in each case, an improvement in gain of about 3 dB or more was observed compared to the conventional antenna. Furthermore, Examples 10 to 15 were also similar.

Note that the values on the vertical axis in FIG. 8 are relative values when the gain of the antenna of the comparative example is set to OdB.

(Effects of the Invention) As explained above, the present invention provides excellent gain and
Moreover, it was possible to provide a microstrip antenna with low loss.

[Brief explanation of drawings]

FIG. 1(a) is a sectional view showing one embodiment of the present invention, FIG. 1(b) is a top view showing one embodiment of the present invention, and FIG. 1(c)
is a sectional view showing another embodiment of the present invention, FIG. 1(d) is a sectional view showing another embodiment of the present invention, and FIG. 1(e) is a sectional view showing another embodiment of the present invention. , FIG. 1(f) is a cross-sectional view showing another embodiment of the present invention, FIG. 1(g) is a cross-sectional view showing another embodiment of the present invention, and FIG. 1(h) is a cross-sectional view showing another embodiment of the present invention. 2(a) is a sectional view showing another embodiment of the present invention, FIG. 2(b) is a top view showing another embodiment of the present invention, and FIG. 3(a) is a sectional view showing another embodiment of the present invention. a) is a sectional view showing another embodiment of the present invention, FIG. 3(b) is a top view showing another embodiment of the present invention, and FIG. 4(a) shows another embodiment of the present invention. A schematic diagram, FIG. 4(b) is a schematic diagram showing another embodiment of the present invention, FIG. 5 is a schematic diagram showing another embodiment of the present invention, and FIG.
Figures (a) and (b) are diagrams for explaining the present invention in detail, Figure 7 is a diagram for explaining the effects of the conventional example, and Figure 8 is the effect of another embodiment of the present invention. 9(a) is a sectional view showing the conventional example, FIG. 9(b) is a top view showing the conventional example, and FIG. 10 is a line diagram explaining the conventional example. be. Explanation of symbols 2. Ground conductor 3゜4, radiating element 5゜6, slot 7゜8, dielectric 9゜10, non-metal part 11, foam dielectric layer feed line metal plate metal tank (b) Fig. 〉 (J Figure 1 (a) (b) Figure (・) Figure 5 Figure 32 (tl) Number of sets (t4) <b> Figure 6-90 Figure 7■ 2■ Figure (1 ) (b) Figure 0 Relative permittivity εr Figure 10

Claims (1)

[Claims] 1. A metal plate (7) having a plurality of slots (6), a plurality of radiating elements (4), a ground conductor (2) and a feed line (
5), a grounding conductor (2) is arranged at a constant interval from the radiating element (4), and the grounding conductor (
A metal plate (7) is arranged at regular intervals on the side without 2), and it is confirmed that the number of slots (6) provided in the metal plate (7) is greater than the number of the radiating elements (4). Features a microstrip patch antenna with a slot plate. 2. The microstrip patch antenna with slot plate according to claim 1, characterized in that, in place of the metal plate (7), a laminate in which a metal layer (9) is formed on the surface of a dielectric (8) is used. 3. The microstrip patch antenna with a slot plate according to claim 2, characterized in that a metal-free portion (10) is formed in the metal layer (9) in place of the slot (6). 4. The microstrip patch antenna with slot plate according to claim 1, wherein the radiating element (4) is provided on one surface of a dielectric material (3) other than air. . 5. The microstrip patch antenna with slot plate according to any one of claims 1, 2, 3, or 4, characterized in that the radiating element (4) is provided on both sides of a dielectric material (3) other than air. . 6. The microstrip patch antenna with slot plate according to any one of claims 1, 2, 3, 4, and 5, wherein the dielectric material (3) other than air is in the form of a film. 7. Claims 1, 2, and 3, characterized in that the ground conductor (2) is provided on one surface of a dielectric material (3) other than air.
6. The microstrip patch antenna with slot plate according to any one of 4, 5, and 6. 8. The position of the slot (6) is the same as that of the radiating element (4).
Claims 1 and 2, characterized in that the portion does not correspond to
8. The microstrip patch antenna with slot plate according to any one of 3, 4, 5, 6, and 7. 9. The microstrip patch antenna with a slot plate according to claim 8, characterized in that, in addition to the slot (6), a slot (6) is provided at a location corresponding to the radiating element (4). 10. Claims 1, 2, 3, 4, 5, characterized in that the slots (6) are arranged point-symmetrically with respect to a location of the metal plate (7) corresponding to the radiating element (4). ,6,7,
10. The microstrip patch antenna with slot plate according to any one of 8 and 9. 11. Claims 1 and 2, characterized in that the slots (6) provided in the metal plate (7) are arranged concentrically.
A microstrip patch antenna with a slot plate according to any one of 3, 4, 5, 6, 7, 8, 9, or 10. 12, one said radiating element (4) and a certain number of slots (
6) is configured as a group of antenna elements, and the antenna elements of a plurality of adjacent groups share a certain number of slots (6). 7
, 8, 9, 10 or 11. The microstrip patch antenna with slot plate according to any one of .