JP2553024Y2 - RF matching termination element - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention is an RF matching terminating element that is indispensable for the RF matching termination of a triple plate strip line (hereinafter, referred to as a strip line) for transmitting microwaves. It is about improvement. [Prior Art] FIG. 5 is a perspective view of a conventional strip line disclosed in Japanese Patent Application Laid-Open No. 56-154804, for example, with a part thereof removed. In the figure, (1a) shows 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 surface of the other surface.
The dielectric substrate A, made of a dielectric material having a relative dielectric constant epsilon _r, which is tightly attached (1b) is a dielectric substrate B that is brought into close contact with the base plate (3) on the entire surface only on one surface. This strip line (2) has advantages such as no radiation loss, no leakage power and no influence on equipment since the system is closed as compared with the micro strip line, so that the antenna power supply and distribution circuit etc. Often used for Fig. 6 shows the RF used for the conventional strip line (2).
FIG. 4 shows a perspective view of the matching termination element with a part thereof removed. In addition, the seventh
The figure shows a cross-sectional view. 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. The microwave power flowing through the strip line (2) flows into the RF matching terminating element (5), and when the microwave power flows through the strip line (2), which is absorbed, the ground plane of the dielectric substrates (1a) and (1b) 3) When the RF matching terminating element (5) in which a potential is generated is sufficiently grounded to the metal plate (4), the RF matching terminating element (5) and the strip line (2) have the same potential, and the microwave is RF. The reflection loss generated when inputting to the matching terminating element (5) is -25 dB or less as shown in FIG. 8, and the microwave power is sufficiently absorbed by the RF matching terminating element (5). [Problems to be Solved by the Invention] Since the conventional RF matching element (5) configured as described above is configured as described above, the strip line (5)
The thickness of the dielectric substrates (1a) and (1b) constituting the above must be equal to the thickness of the RF matching termination element (5). When the thickness of the dielectric substrates (1a) and (1b) is thicker than the RF matching terminating element (5) as shown in FIG.
Since the matching terminating element (5) is not at the same potential, the reflection loss that occurs when microwaves enter the RF matching terminating element (5) becomes unstable from -15 dB to -20 dB as shown in Fig. 10, and There was a problem that microwave power was not sufficiently absorbed by the RF matching termination element. Further, the thickness of the RF matching terminating element (5) and the dielectric substrate (1a) constituting the strip line (2),
Since the thickness of (1b) is equal, the design of the microwave circuit is restricted. This invention has been made in order to solve the above-mentioned problems. Even when the thickness of the dielectric substrates (1a) and (1b) is larger than that of the RF matching termination element (5), the strip line (2) can be used. The RF matching terminating element (5) has the same potential, reduces the reflection loss that occurs when microwave power is input to the RF matching terminating element (5), and sufficiently absorbs the microwave power into the RF matching terminating element (5). The purpose is to: [Means for Solving the Problems] The RF matching terminating element according to the present invention has metal plates connected to both end surfaces in the thickness direction of the RF matching terminating element. The metal plates are connected to both end surfaces in the thickness direction of the RF matching terminating element so as to be equal in thickness to the two dielectric substrates. It is electrically grounded to a metal plate holding the substrate so as to have the same potential. [Operation] In the present invention, the strip line (2) and the RF matching terminating element (5) have the same potential due to the metal plates attached above and below the RF matching terminating element (5), and the microwave power RF matching terminating element ( The reflection loss that occurs when inputting to (5) is improved, and the microwave power is sufficiently absorbed by the RF matching termination element (5). [Embodiment] Fig. 1 is a perspective view, partially omitted, showing an embodiment of the present invention. (1a) to (5) in the figure are exactly the same as the above-mentioned conventional RF matching terminating element. (6) is a metal plate provided 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 cross-sectional view of the RF matching termination element (5) into which the metal plate (6) has been inserted. FIG. 3 is an enlarged view of a metal plate (6) having the same thickness of the dielectric substrates (1a) and (1b) and the RF matching terminating element (5). In the RF matching terminating element (5) configured as described above, by attaching two metal plates (6), the metal that holds down the RF matching terminating element (5) and the dielectric substrates (1a) and (1b) When the potential difference generated in the plate (4) and the microwave power flow through the strip line (2), the potential difference generated between the dielectric substrate (1a) and the ground plate (3) of (1b) becomes the same potential, and the microwave power is RF matched. The reflection loss that occurs when the signal is input to the termination element (5) is -25 dB or less as shown in FIG. 4, and the microwave power is sufficiently absorbed by the RF matching termination element (5). In the above embodiment, the metal plate (6) is shown as a cylinder, but may be formed as a rectangle. Although the strip line (2) is formed in the middle of the two dielectric substrates, the metal plate (6) having a different thickness is attached to the RF matching terminator (5) in both the upper and lower directions, and thus the microstrip is achieved. This has the effect of sufficiently absorbing wave power. Although two dielectric substrates have been described here, the present invention can also be applied to an RF matching terminating element used in a multilayer dielectric substrate having two or more dielectric substrates. [Effects of the Invention] As described above, this invention is applied to the design of RF matching terminating elements such as micro-strip antennas and feed circuits that use a dielectric substrate using strip lines. Since the thickness of the dielectric substrate can be selected without being restricted by the thickness of the matching terminating element, there is an effect that the degree of freedom is given to the design. In addition, even when the thickness of the two dielectric substrates and the thickness of the RF matching terminating element are different, the present invention can provide a strip line and an RF matching termination element.
The matching terminator has the same potential, and the reflection loss that occurs when microwave power is input to the RF matching terminator can be reduced.
This has the effect that deterioration of the electrical characteristics of the RF matching termination element can be prevented.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing one embodiment of the present invention with a part removed, FIG. 2 is a sectional view of the present invention, FIG. 3 is an enlarged view of a metal plate used in the present invention, FIG. 4 is an electrical characteristic diagram of the RF matching terminating element according to the present invention, FIG. 5 is a perspective view of a strip line with a part removed, FIG. 6 is a perspective view of a conventional RF matching terminating element with a part removed, and FIG. FIG. 7 is a cross-sectional view of a conventional RF matching termination element, FIG. 8 is an electrical characteristic diagram of the conventional RF matching termination element, and FIG. 9 is a cross section when the thickness of the dielectric substrate and the thickness of the RF matching termination element are different. FIG. 10 and FIG. 10 are electrical characteristic diagrams 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 down the dielectric substrate, and (5) is an RF matching termination. The element (6) is a metal plate. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (1)

(57) [Rules for requesting registration of utility model] A dielectric substrate having a conductor attached to only one surface, a dielectric substrate having a conductor attached to one surface and a strip line attached to the other surface, and these two dielectric substrates are stacked such that each conductor is on the outside. In the RF matching termination element thinner than the thicknesses of the two dielectric substrates connected to the triplate strip line configured together, a metal plate is connected to both end faces in the thickness direction of the RF matching termination element, and the RF matching termination element is connected to the RF matching termination element. By connecting metal plates to both end surfaces in the thickness direction of the RF matching terminating element so that the thickness of the two metal plates becomes equal to the thickness of the two dielectric substrates, the potential of the outer conductor of the RF matching terminating element becomes metal. An RF matching terminating element characterized in that it is electrically grounded to a metal plate that holds said two dielectric substrates via a plate and has the same potential.