JPS6126844B2 - - Google Patents

Description

[Detailed Description of the Invention] This invention applies to comparatively high frequency bands, especially VHF bands and UHF bands.
This paper relates to the improvement of high-frequency devices that are widely used in the microwave and microwave bands.

First, the conventional high frequency device shown in FIG. 1 will be briefly explained.

In Figure 1, a is a cross-sectional view, and b is a longitudinal cross-sectional view, 1 is an outer conductor, 2 is an inner conductor, 3 is a semi-coaxial resonator, 4 is an input/output loop, and 5 is a resonator. Loops 6 and 7 are input/output terminals that connect the devices 3 to each other.

Here, the loops 4 and 5 connect the input/output terminals and the resonator 3 to each other by a current induced by the magnetic field in the resonator 3. For this reason, the loops 4 and 5 are provided in a portion of the resonator 3 where the magnetic field is large, and form a closed loop by connecting both ends to the outer conductor.

Now, if a wave with frequency ₀ is introduced into terminal 6 and the length of inner conductor 2 is selected to be approximately 1/4 of the wavelength of frequency ₀ , the frequency coupled by loops 4 and 5 will be
The _zero wave sequentially resonates in the resonator 3 and is taken out to the terminal 7. Since the resonator 3 does not resonate with waves having frequencies other than ₀ , the coupling to the terminal 7 is very small and most of the power is reflected. In this way, the high frequency filter shown in FIG. 1 has a function as a bandpass filter.

By the way, in conventional high-frequency devices, it is difficult to accurately attach the probes 4 and 5 to the outer conductor 2 in the resonator 3 using electrically good connection means, and good characteristics cannot be obtained. There were flaws.

In order to eliminate these drawbacks, the present invention uses a self-closed loop as the loop 5 for coupling the resonators 3 to each other, and will be described in detail below with reference to the drawings.

FIG. 2 shows an embodiment of the present invention;
b is a cross-sectional view and a vertical cross-sectional view corresponding to FIGS. 1a and 1b, respectively. In Figure 2, 1 to 7 are the same as in Figure 1, 8 is a metal plate with holes for forming the outer conductor of the coaxial line, 9 and 10 are dielectric plates, and 11 is the connector 6 and 7. It is a conductor in the coaxial line.

Here, the loops 4 and 5 are formed of strip lines sandwiched between dielectric plates 9 and 10.
The loop 4 is connected to the inner conductor 11 at one end and to the metal plate 8 at the other end. Further, the loop 5 forms a closed loop by itself and is insulated from the outer conductor 2.

Therefore, in the high frequency filter of the present invention, the loops 4 and 5 can be formed by etching, and highly accurate and uniform loops can be easily obtained. In particular, since the loop 5 does not need to be connected to the outer conductor 1, it can be attached easily and accurately.

At this time, it is necessary to provide slots in the outer conductor 1 for inserting the loops 4 and 5 and the dielectric plates 9 and 10, but the slots have a shape that does not block the current flowing through the resonator 3. Therefore, the functionality of the high-frequency device is not impaired.

As described above, in the high frequency device according to the present invention, since the loop 5 is formed by a closed strip line, it is possible to easily and accurately attach a device having a uniform and accurate shape. , it has the advantage of being able to stably obtain good characteristics.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a conventional high frequency device, FIG. 1a is a cross-sectional view, FIG.
b is a cross-sectional view, and b is a longitudinal cross-sectional view. In the figure, 1 is an outer conductor, 2 is an inner conductor, 3 is a semi-coaxial resonator, 4 and 5 are loops, and 9 and 10 are dielectrics. In the drawings, the same or corresponding parts are denoted by the same reference numerals.

Claims (1)

[Claims] 1. A high frequency device in which a plurality of semi-coaxial resonators are coupled in a loop, characterized in that the loop that couples the semi-coaxial resonators to each other is formed by a closed strip line.