JPH0746962Y2 - RF matching termination element - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention proposes an RF matching termination element which is indispensable for RF matching termination of a triplate type strip line (hereinafter referred to as a strip line) that transmits microwaves. It is about improvement.

[Conventional technology]

FIG. 5 shows a perspective view of the conventional strip line shown in, for example, Japanese Patent Laid-Open No. 56-154804 with a part thereof removed. In the figure, (1a) is a strip line (2) having a line width W on a part of one surface and a ground plate (3) made of metal on the entire other surface.
The dielectric substrates A and (1b) made of a dielectric material having a relative permittivity εr in close contact with each other are the dielectric substrate B in which the ground plane (3) is in close contact with only one surface.

This stripline (2) has advantages such as no radiation loss and no influence on leakage power and equipment because the system is closed compared to the microstripline, and therefore antenna feeding and distribution circuits, etc. Often used for.

FIG. 6 shows a perspective view of the RF matching termination element used in the conventional strip line (2) with a part thereof removed. A cross-sectional view is shown in FIG.

In the figure, (4) is a metal plate that holds two dielectric substrates,
(5) is an RF matching termination element.

Next, the operation principle will be described. Strip line (2)
The microwave power flowing through the RF power supply flows into the RF matching termination element (5) and is absorbed. When microwave power flows through the strip line (2), an electric potential is generated between the ground planes (3) of the dielectric substrates (1a) and (1b). When the RF matching termination element (5) is sufficiently grounded to the metal plate (4), the RF matching termination element (5) and the strip line (2) have the same potential, and the microwave is applied to the RF matching termination element (5). The reflection loss that occurs when input is -25 dB or less as shown in FIG. 8, and the microwave power is sufficiently absorbed by the RF matching termination element (5).

[Problems to be solved by the invention]

Since the conventional RF matching element (5) is configured as described above, the thicknesses of the dielectric substrates (1a) and (1b) forming the strip line (5) and the thickness of the RF matching termination element (5). Must be equal. Dielectric substrate (1a), (1b)
9 is thicker than the RF matching termination element (5) as shown in FIG. 9, the RF matching termination element (5) and the ground plane (3) are not grounded and the strip line (2) and the RF matching termination element (5) are Since the potentials are not the same, the reflection loss that occurs when microwaves enter the RF matching termination device (5) is −15 as shown in Fig. 10.
It became unstable from dB to -20 dB, and there was a problem that microwave power was not absorbed enough in the RF matching termination element. Further, since the thickness of the RF matching terminating element (5) and the thickness of the dielectric substrates (1a) and (1b) forming the strip line (2) are made equal, the design of the microwave circuit is restricted. There was a problem.

The present invention has been made to solve the above problems, and even if the dielectric substrates (1a) and (1b) are thicker than the RF matching termination element (5), the strip line (2)
The RF matching termination element (5) and the RF matching termination element (5) are at the same potential, and the reflection loss that occurs when microwave power is input to the RF matching termination element (5) is reduced, and the microwave power is sufficiently absorbed by the RF matching termination element (5). The porpose is to do.

[Means for solving problems]

The RF matching termination device (5) according to the present invention has the same thickness direction as the dielectric substrates (1a) and (1b) forming the strip line (2). The springs made of metal are attached above and below the.

[Action]

In this invention, the RF matching termination element (5) and the ground plane (3) are grounded by the metal springs attached above and below the thickness direction of the RF matching termination element (5), and the strip line (2) and the RF line are connected.
Matching termination element (5) has the same potential and microwave power RF
The reflection loss that occurs when inputting to the matching termination element (5) is improved, and the microwave power is sufficiently absorbed by the RF matching termination element (5).

[Example of device]

FIG. 1 is a perspective view showing an embodiment of the present invention with a part thereof removed. In the figure, (1a) to (5) are exactly the same as the above-mentioned conventional RF matching termination element. (6) is a spring made of metal attached to make the thickness of the RF matching termination element (5) the same as that of the dielectric substrates (1a) and (1b).

FIG. 2 is a sectional view of the RF matching termination element (5) in which the metal spring (6) is inserted.

Further, in FIG. 3, a spring (6) made of metal having the same thickness as the dielectric substrates (1a) and (1b) and the RF matching termination element (5).
FIG.

In the RF matching terminator (5) configured as described above, a metal that holds the RF matching terminator (5) and the dielectric substrates (1a) and (1b) by attaching two metal springs (6) The potential difference generated on the plate (4) and the microwave power flow to the strip line (2) have the same potential difference between the dielectric substrate (1a) and the ground plane (3) of (1b), and the microwave power is RF matched. The reflection loss that occurs when inputting to the terminating element (5) is -25 dB or less as shown in Fig. 4, and microwave power is sufficiently absorbed by the RF matching terminating element (5).

In the above embodiment, the metal spring (6) is shown as a cylinder, but it may be formed in a quadrangle. Although the strip line (2) is formed in the middle of the two dielectric substrates, it is possible to attach a metal spring (6) of different thickness to the RF matching termination device (5) regardless of whether the strip line (2) is on or off. The effect of sufficiently absorbing wave power is exerted.

Although two dielectric substrates are described here, the present invention can be applied to an RF matching termination element used in a multilayered dielectric substrate having two or more dielectric substrates.

[Effect of device]

As described above, the present invention is applied to designing an RF matching termination element such as a microstrip antenna or a connecting circuit configured by using a dielectric substrate using a strip line. Since the thickness of the dielectric substrate can be selected without being constrained by the thickness, there is an effect that the degree of freedom in design is given.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention with a part thereof removed, and FIG. 2 is a sectional view showing an RF matching termination element of the present invention.
FIG. 3 is an enlarged view of a metal spring used in the present invention, FIG. 4 is an electrical characteristic diagram of an RF matching termination device according to the present invention, FIG. 5 is a perspective view in which a strip line is partially removed, and FIG. Fig. 7 is a perspective view of the RF matching termination device of Fig. 7 with some parts removed, Fig. 7 is a sectional view of the conventional RF matching termination device, Fig. 8 is an electrical characteristic diagram of the conventional RF matching termination device, and Fig. 9 is a dielectric. Substrate thickness and RF
Fig. 10 is a sectional view when the thickness of the matching termination element is different, and Fig. 10 is an electrical characteristic diagram when the thickness of the dielectric substrate and the RF matching termination element are different. In the figure, (1a) and (1b) are dielectric substrates A and B, (2) is a strip line, (3) is a ground plane, (4) is a metal plate that holds the dielectric substrate, and (5) is an RF matching termination. The element, (6), is a metal spring. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] 1. A dielectric substrate having a conductor only on one side, a conductor having a conductor on one side and a strip line on the other side, and these two dielectric substrates each having a conductor. In an RF matching termination device thinner than the thickness of the two dielectric substrates connected to the triplate-type strip line that is superposed on the outside, a metal spring is provided on both end faces in the thickness direction of the RF matching termination device. And the metal springs are connected to both end faces in the thickness direction of the RF matching terminator so that the thicknesses of the RF matching terminator and the two metal springs are equal to the thicknesses of the two dielectric substrates. The potential of the outer conductor of the matching terminating element passes through the metal spring and the above 2
An RF matching termination element, which is electrically grounded to a metal plate that holds a dielectric substrate and has the same potential.