JPH0257003A - Print antenna with reflection board - 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 a. Field of Industrial Application The present invention relates to a dual-frequency printed antenna with a reflector suitable for use as a base station antenna for land mobile stations such as car telephones.

b. Conventional technology Traditionally, 800MHz was used for land mobile communications such as car telephones.
The base station antenna is either an omnidirectional antenna placed on the top of the tower, or multiple directional antennas placed on the side of the tower, and combined to create an omnidirectional directional characteristic. I was getting . However, the development of land mobile communications in recent years has been remarkable, especially in large cities where 800M
Systems using the Hz band are expected to be unable to cope with the increase in the number of mobile stations in the near future, and a shift to a new frequency band, such as the 1.5 GHz band or the 2.4 GHz band, is being considered.

The base station antennas used for this new frequency band, 1.5 GHz band and 2.4 GHz band, are currently 800 MHz.
This can be easily realized by shortening the structure 5 dimensions of the antenna used in the band in terms of the wavelength ratio.

However, the transition to the two frequency bands using independent base station antennas for each frequency band requires consideration of the installation capacity of the steel tower, the installation space of the two power supply cables, etc.
It is difficult to install on the same tower. Therefore, frequency sharing antennas are being considered, and printed antennas with reflectors using parasitic elements have already been proposed.

As an antenna of this type, FIG. 5(A) shows a perspective view of a conventional printed antenna with a repellent plate, and FIG. 5(B) shows a plan view thereof. In the figure, a dielectric substrate 1 has each radiating element 2a, 2b of a strip dipole antenna 2 on both sides thereof.
The radiating elements 2a and 2b are formed at positions rotated 180 degrees from each other about the central axis of the dipole antenna 2. Reference numeral 3 denotes a parasitic element, and each of the elements 3a and 3b is provided on both sides of the dielectric substrate 1 in parallel with each of the radiating elements 2a and 2b of the dipole antenna 2, with an insulating member 4 in between.

In the printed antenna with a reflector, the dielectric substrate 1 having such a strip dipole antenna 2 is mounted perpendicularly to the central reflector 5b of the borrowed corner reflector 5 in which the opening angle of both side plates 5a and 5a is 180 degrees or more. It was erected. Note that 6 is a feeding point of the printed antenna.

The directivity characteristics of this printed antenna with a reflector in the applicable frequency band are nearly uniform over a wide range.

C1 Problem to be Solved by the Invention However, in the case of using a parasitic element 3 like the conventional printed antenna with a reflector, the parasitic element 3
cannot be formed directly on both sides of the dielectric substrate 1 as a slip element, which poses the problem that the mounting structure of the parasitic element 3 is complicated and the cost is high economically. Ta.

The present invention has been made in view of the above problems, and its purpose is to provide a structure in which a radiating element that resonates at a first frequency and a second frequency is formed on a dielectric substrate for frequency sharing. It is an object of the present invention to provide a printed antenna with a reflector that can simplify the directional characteristics of the first frequency and the second frequency in the horizontal plane.

63 Means for Solving the Problems The structure of the present invention to achieve the above-mentioned object is that in the reflector-equipped pudding 1 to antenna having a radiating element and a reflecting plate formed on a dielectric substrate, (1) the radiating element is , is formed of a first radiating element that resonates at a first frequency on the surface of the dielectric substrate, and a second radiating element that resonates at a second frequency, and is disposed at a distance from the reflecting plate in a perpendicular direction. Approximately 1 at each frequency
/4 wavelength, and the first and second radiating elements are each formed to have a self-complementary structure.

(2) The printed antenna with a reflector of item (1) above,
It is characterized by being arranged in multiple stages in the vertical direction.

e. Function: The printed antenna with a reflector configured as described above is
Said 1st. By arranging the dielectric substrates on which the second radiating elements are respectively formed in a direction perpendicular to the reflecting plate so that the distance is approximately 1/4 wavelength at each of the frequencies, a good result can be obtained at each of the frequencies. The return loss amount can be obtained, and the directivity characteristics in the horizontal plane can be made almost the same. Furthermore, the above-mentioned No. 1. Since the second radiating element can be formed on the same dielectric substrate surface, the structure is extremely simplified.

f. Examples Hereinafter, preferred embodiments of the present invention will be described in detail by way of example based on the drawings.

FIGS. 1(A) and 1(B) are examples of the printed antenna with a reflector of the present invention, and FIG. 1(A) is a perspective view of the printed antenna with a borrowed corner reflector having a 180-degree beam with directivity in the horizontal plane. , FIG. 1(B) is a perspective view of an antenna with a 90-degree corner reflector having a 60-degree beam with directivity in the horizontal plane.

In the figure, a printed antenna 10 includes a dielectric substrate 1
The first radiating elements 12a and 12b constituting the first strip dipole 12 are placed on both sides of the first strip dipole 12 at a first frequency f1.
second radiating elements 13a, 13b constituting the second strip dipole 13;
is formed so as to resonate at the second frequency f2. the first radiating elements 12a, 12b and the second radiating element 13
a and 13b are formed in one direction opposite to each other at right angles to the feed lines 14a and 14b formed in the center of the dielectric substrate 11, and the first radiating elements 12a and 12b are formed at positions rotated by exactly 180 degrees around the central axis of the dipole antenna 12 so as to have a mutually self-complementary structure. And the radiating element 12a
, 12b is approximately % of the wavelength λ1 of the first frequency f1. Further, second radiating elements 13a, 1
3b is also formed to have a self-complementary structure in the same way as above, and the distance between its both ends is determined by the second frequency f2 (f2>fl)
The wavelength λ2 (λ2<λ1) is approximately 2.

Such a printed antenna 10 is installed on both side plates 15a, 1
The center reflector 15b (Fig. 1 (A)) of the borrowed corner reflector 15 in which the aperture angle of 5a is a dominant angle of 180 degrees or more, or the 90-degree corner reflector in which the aperture angle of both side plates 16a and 16b is 90 degrees. The respective distances of the first radiating elements 12a, 12b and the second radiating elements 13a, 13b in the perpendicular direction from the 16 central reflecting plates 16b (FIG. 1(B)) are as follows:
The wavelength λ1 at each resonance frequency f+, fz. λ
2 about λI/4. Arrange so that the distance is about λ2/4. In this case, 1. Second radiating element 12a.

12b, 13a, 13b are the corner reflecting plates 15;
, or 16 outer reflectors 15a, 15a or 16a
, 16a, and the first . Part 2
The central axes of the radiating elements 12a, 12b13a, 13b are
The outer reflecting plate 15a, 15a or 16a, 16
It is arranged so as to coincide with the bisector of a. In addition,
17 is a feeding point of the printed antenna 10.

Figures 2 (A) and (B) are characteristic diagrams showing the measured return loss of the printed antenna with a reflector in this example, and Figure 2 (8) shows the borrowed corner reflection shown in Figure 1 (A). FIG. 2(B) shows the return loss characteristics of the antenna with a plate, and that of the antenna with a 90-degree corner reflector shown in FIG. 1(B). In both cases, sufficient return loss is obtained at the first frequency fl and the second frequency f2.

FIGS. 3(A) and 3(B) show the directivity characteristics in the horizontal plane of the printed antenna with a reflector according to this embodiment. Figure 3 (
A) is the directional characteristic of the antenna with a borrowed corner reflector shown in FIG. 1(A), where the solid line indicates the first frequency f, and the dotted line indicates the second frequency f2. The antenna with a borrowed corner reflector was designed to form a 180-degree beam in the horizontal plane, and it was possible to obtain almost the same directivity characteristics in the horizontal plane for both the first and second frequencies, fz. Figure 3 (B) shows the directivity characteristics of the antenna with a 90-degree corner reflector shown in Figure 1 (CB), where the solid line represents the first frequency fI and the dotted line represents the second frequency f2, both of which are within the same horizontal plane. Directional characteristics have been obtained.

FIGS. 4(A) and 4(B) show another embodiment of the printed antenna with a reflector according to the present invention, in which the printed antenna with a reflector shown in the above embodiment is arranged vertically in multiple stages (four stages in the figure, however, (The top and bottom ones are not shown) are arranged so as to overlap.

Figure 4 (A) is a partially cutaway perspective view of a multi-stage printed antenna with a borrowed corner reflector that has a 180-degree beam directional characteristic in the horizontal plane, and Figure 4 (B) has a 180-degree beam directional characteristic in the horizontal plane.
1 is a partially cutaway perspective view of a multi-stage printed antenna with a 90-degree corner reflector having a 90-degree beam; FIG.

In the same figure, the printed antenna 20 is formed by arranging and forming the printed antennas 10 of the above embodiment on a common dielectric/electric substrate 21 in a plurality of vertically stacked stages according to the above embodiment, and also having each radiating element are connected in parallel and feed point 2
Connected to 2. In addition, for 25, the opening angle of both side plates is 1
A borrowed corner reflector with a dominant angle of 80 degrees or more, 26 a 90 degree corner reflector with both side plates having an opening angle of 90 degrees, and 27 a dielectric cover.

In this way, by arranging the printed antennas 10 in multiple stages in the vertical direction, a high gain antenna can be obtained.

Note that the technology of the present invention is not limited to the technology in each of the embodiments described above, and means of other modes that perform the same function may be used. , can be added.

g0 Effects of the Invention As is clear from the above description, the present invention includes a first radiation element that resonates at a first frequency on a dielectric substrate surface, and a second radiation element that resonates at a second frequency as a radiation element. These radiating elements are arranged perpendicularly from the reflector so that the distance is approximately 1/4 wavelength at each frequency, and the first and second radiating elements are self-contained. Since it is formed to have a complementary structure, good return loss can be obtained at the first frequency and the second frequency,
Moreover, an antenna that can obtain almost the same directivity characteristics in the horizontal plane can be realized.

At the same time, since the radiating elements can be formed on the same dielectric substrate, it is possible to provide an antenna with an extremely simple structure and low cost compared to conventional antennas.

Furthermore, by arranging such printed antennas with reflectors in multiple stages in the vertical direction, a high gain antenna can be obtained.

[Brief explanation of the drawing]

1(A) and 1(B) show an embodiment of the printed antenna with a reflector plate of the present invention, FIG. 1(A) is a perspective view of the print antenna with a borrowed corner reflector plate, and FIG. 1(B) Ba9
A perspective view of a printed antenna with a 0 degree corner reflector. Figures 2 (A) and (B) are diagrams showing the return loss characteristics of each antenna. Figure 3 (A) and (B) are horizontal planes of each antenna. Diagram showing inward directivity characteristics, Figure 4 (Δ),
(B) shows another embodiment of the present invention, FIG. 4(A) is a partially cutaway perspective view of a multi-stage printed antenna with a borrowed corner reflector, and FIG. 4(B) is a multi-stage printed antenna with a 90-degree corner reflector. A partially cutaway perspective view of the antenna, Figure 5 (Δ) is a perspective view of a conventional printed antenna with a reflector, Figure 5 (B)
is a plan view of the conventional antenna. 10.20... Printed antenna, IL21... Dielectric substrate, 12a, 12b... First radiating element, 13a, 13
b... Second radiating element, 15.25... Borrowed corner reflector, 15b, 16b... Center reflector, 16.26... 90 degree corner reflector. Book (A) No. 1 (B) Procedural amendment (voluntary) 1999 8 1, Indication of the case 1988 Patent Application No. 208767 2, Name of the invention Pudding I antenna with reflector plate 3, Case of the person making the amendment Name related to electricity

Claims (1)

[Scope of Claims] 1. A printed antenna with a reflector that includes a radiator and a reflector formed on a dielectric substrate, wherein the radiator comprises:
A first radiating element that resonates at a first frequency and a second radiating element that resonates at a second frequency are formed on the surface of the dielectric substrate, and the distance from each of them in the perpendicular direction from the reflecting plate is 1. A printed antenna with a reflector, characterized in that the first and second radiating elements are arranged so as to have a frequency of approximately 1/4 wavelength, and each of the first and second radiating elements is formed to have a self-complementary structure. 2. In a printed antenna with a reflector having a radiating element and a reflector formed on a dielectric substrate, the radiating element is
A first radiating element that resonates at a first frequency and a second radiating element that resonates at a second frequency are formed on the surface of the dielectric substrate, and the distance from each of them in the perpendicular direction from the reflecting plate is The first and second radiating elements are arranged so that the frequency is approximately 1/4 wavelength, and the first and second radiating elements are each formed to have a self-complementary structure, and furthermore, they are arranged in multiple stages in the vertical direction. Features a printed antenna with a reflector.