JPH01183201A - Printed dipole antenna - Google Patents

Abstract

PURPOSE:To use the title antenna in a wide band or plural frequency bands by giving the superconducting layer of a prescribed form and size between a dipole element and a dielectric substrate and providing a magnetic field generation source near the back in a direction to which a radio wave is radiated. CONSTITUTION:The conductive board or the thin film 4 of a superconducting body with the form and size larger than the dipole element 1 is installed between the dipole element 1 of a metallic thin board and the dielectric substrate 2. The magnetic field generation source (electromagnetic coil, etc.) 5 supplying a magnetic field is provided near the back in the direction to which the radio wave of the antenna is radiated, and the size of the magnetic field generated in the electromagnetic coil 5 is set larger than a critical magnetic field where the superconducting radiation element 4 comes not to show superconductivity. With switching ON/OFF the magnetic field synchronized with the frequency- switching of the radiation element 4, the size of the dipole element 1 can equally be changed and an objective radiation characteristic can be obtained with respect to the radio wave of plural frequency bands which are comparatively detached at every frequency.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention H relates to a printed dipole antenna used for transmitting and receiving radio waves in the UHF band, micro TFJL\W, and millimeter wave bands.

[Conventional technology]

Conventionally, this type of antenna has been used either as a single printed dipole antenna or as an element antenna constituting an array antenna.
i. It is configured as shown in Figure 3. In the figure, (1
) is a dipole element, (2) is a dielectric substrate, and +3) is a feed line. In addition, in the case of an antenna used outdoors as another component, the entire surface or the radiating portion of the antenna is often covered with a radome.

Next, the function of each component will be explained. (The dipole element 11 is formed by etching a metal foil (usually a thin copper foil) on a dielectric substrate (2) into a predetermined shape and size such as a rod shape, and its specifications are as follows. It is determined by the frequency band used and the required radiation characteristics (mainly gain, beam width, radiation pattern, impedance, etc.).Also, by maintaining a predetermined spacing between the dielectric substrate +21H and the dipole element il1, it is possible to use it as an antenna. It supplements the strength and is made of a material with low dielectric constant and low loss such as glass fiber reinforced Teflon.The feed line (3) is a medium that feeds power from the transmitter/receiver to the antenna via the feed circuit. Near the input end of , two dipole elements (printed microstrip lines similar to 11 are used).

Although not shown in Figure 2, the radome is another component when using nine antennas outdoors.

It is installed to prevent raindrops and moisture from entering the dielectric substrate (2) and power supply line (3), and the material is a dielectric that maintains airtightness and does not cause reflection or transmission loss to radio waves. is used.

[Problem to be solved by the invention]

Conventional printed dipole antennas are basically configured with one or more antennas, so if you try to use this antenna in a wide band (for example, a band of several tens of inches or more) or multiple frequency bands, you will have to use fixed dimensional specifications. On the other hand, because the frequency used is widened, the radiation characteristics such as gain, beam width, radiation pattern, impedance, etc. will differ significantly within the band, making it impossible to maintain the specified radiation characteristics, and trying to maintain this will result in high There was a problem that it could only be used in a band of 10 to 2 (1 or less).

This invention was made to solve the above-mentioned problems, and in particular, it is aimed at obtaining a printed dipole antenna that can be used in a wide band or in a plurality of frequency bands.

[Means to solve the problem]

In the printed dipole antenna according to the present invention, a superconductor (for example, Ba-Y-Cu-0 systems and organic compounds)
The antenna is equipped with a thin plate or thin film, and is further equipped with a magnetic field generation source (such as an electromagnetic coil) for supplying a magnetic field near the rear of the antenna in the direction in which radio waves are radiated.

[Effect]

The printed dipole antenna of the present invention includes a superconductor layer having a predetermined shape and dimensions between a dipole element made of a thin metal plate and a dielectric substrate, and a magnetic field generation source located near the rear of the wave radiation direction. By providing, when the E & field is lower than the critical magnetic field HC of the superconductor or is not applied, the superconductor layer acts as a conductor and! Electrically, it operates as if the shape and dimensions of the dipole element had become larger, and when a magnetic field higher than the critical magnetic field HC is applied, the superelectric layer loses its superconductivity and operates as a dielectric, resulting in electrical damage. , the size of the dipole element is the same as that of the thin metal plate.

〔Example〕

An embodiment of the present invention will be explained below with reference to FIG. FIG. 1 is a cross-sectional view of the printed die-ball naantenna of the present invention. In FIG. 91, (l) is a dipole element;
(2) is a dielectric substrate, and (3) is a power supply line.

1411ri superconductor radiation element, (5) is a magnetic field generation source,
Specifically, it is an electromagnetic coil.

ill's dipole element, (21H dielectric substrate, (3)
The feed line is the same as the conventional printed dipole antenna explained in the third case, and will not be explained again.

The superelectric radiation element (4) provided between the dipole element 111 and the dielectric substrate (210) has a larger shape and dimension than the dipole element (1), and its superconductivity is broken by a relatively small critical magnetic field 1 (c). It is sufficient to use a material whose thickness is about twice that of Skin Dave's.Also.

When the superconductor radiating element (4) operates as a conductor, it is electrically connected to the dipole element ill. The magnitude of the magnetic field generated by the NMi coil in (5) is
The magnetic field is set to be above a critical magnetic field at which the superconducting radiation element (4) no longer exhibits superconductivity.

When the antenna is configured as described above, even if the frequencies used to excite the antenna are two relatively distant frequencies, such as the 4GH2 band and the 6GH2 band.

As long as you use it while switching between both IT controllers.

By applying a 0N10FF magnetic field synchronized to the frequency switching to the superconductor radiation element (4) provided between the dipole element (1) and the dielectric substrate (2), the dipole element (1) is generated. It is possible to realize a predetermined radiation characteristic in the image frequency band by varying the size isometrically.

That is, if no magnetic field is applied at low frequency f1, and a magnetic field greater than the critical magnetic field is applied at high frequency f2, the superconductor radiating element (4) operates as a conductor at low frequency, resulting in 9 equivalent radiation. The size of the element is the dipole element (1) plus the shape and dimensions of the superconductor radiating element (4). On the other hand, at high frequencies, the superconducting state is broken and only the dipole element Tll operates as a radiating element.

Therefore, if the outer shape and dimensions of the superconductor radiating element are determined according to the low frequency af1, and the dimensions and specifications of the dipole element +11 are determined according to the high frequency f2, the predetermined values can be obtained for each of the two frequencies. A printed dipole antenna with radiation characteristics can be realized.

In the above embodiment, one layer of superconductor radiating element 141t is provided between dipole element +11 and dielectric substrate (2).
-Although we have shown an example where the dipole element +
The same effect can be obtained even if a dielectric material is sandwiched between the superconductor 11 and a thin film-like superconductor radiating element (4) provided on the surface of the dielectric material. However, in this case, the superconductor radiating element (4) must be directly electrically connected to the feeding end.

In the above explanation, an example was shown in which the superconductor radiating element (4) was made of only one layer, but the same applies to the case where it has multiple layers as shown in FIG. 2, and in this case.

By providing materials with different critical magnetic fields for each layer.

By applying the magnetic field with variable strength in multiple stages,
Furthermore, effects similar to those described above can be obtained for a plurality of frequencies of two or more.

In addition, (4a), (4b), and (4C)h in the figure are superconductor radiating elements in which the tt critical magnetic field increases sequentially.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to obtain desired radiation characteristics for each frequency of radio waves in a plurality of relatively distant frequency bands using one printed dipole antenna.

In addition, especially when used in space, even so-called high-temperature superconductors can be used without the need for cooling, as long as they are not directly exposed to sunlight. A single printed dipole antenna can handle both transmitting and receiving waves, which has a significant effect in reducing the cost and space of the entire antenna system.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a printed dipole antenna according to an embodiment of the present invention, FIG. 2 is a perspective view showing another embodiment of the invention, and FIG. 3 is a perspective view showing a conventional printed dipole antenna. In Figure 9, Tll is a dipole element, and (2) is a dielectric substrate. (3) is a feed line, (4) is a superconductor radiating element, (5)
is an electromagnetic coil. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Claims] In a printed dipole antenna, in which dipole elements made of metal foil or metal thin film are printed on both sides of a dielectric substrate, there is a space between each printed dipole element and the dielectric substrate that is larger than the dipole element. A radiation element made of a superconductor thin plate or thin film of different dimensions is installed in one layer or multiple layers with different critical magnetic fields, and a magnetic field generation source capable of applying and blocking the critical magnetic field of the superconductor is provided near the dipole element. Features a printed dipole antenna.