JPH0856104A - Resonator - Google Patents

Abstract

PURPOSE:To facilitate the adjustment of the resonance frequency by connecting grounding capacitor of a different capacitance to two bisecting points of a ring transmission line or providing a stub whose length differs to the points so as to reduce the length of the resonance line. CONSTITUTION:A 1st lumped constant grounding capacitor 12 and a 2nd lumped constant grounding capacitor 13 are provided to the inside of a ring line 11 at bisecting points of the ring line consisting of a strip line or a microstrip line to form the ring resonator 14. Thus, part of the ring line 11 is replaced with the lumped constant grounding capacitors 12, 13 and the entire size of the resonator is made small. Furthermore, since the capacitance of the lumped constant grounding capacitors 12, 13 is selected different, the degree of freedom of the design is high and the adjustment is made easy. First and second stubs 22, 23 whose length differ are provided to bisecting points of the ring transmission line 21 in the ring resonator 24, then the similar operation and advantage to which provided with the lumped constant grounding capacitors are realized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resonator used in various radio equipment for high frequencies, communication equipment, oscillators of measuring instruments and the like.

[0002]

2. Description of the Related Art In recent years, the demand for mobile communication has rapidly increased, and systems using the quasi-microwave band which is a new applicable frequency resource have been developed. A TEM mode resonator is most often used as a small resonator used in a high-frequency oscillator. Among these resonators, a one-wavelength ring resonator composed of a strip line or a microstrip line is used as a line or a substrate. It is widely used as a standard resonator for the characterization of dielectric materials.

A conventional resonator will be described below. FIG. 5 shows a plan view of the configuration of a conventional resonator. In FIG. 5, 1 is a ring-shaped transmission line, and 2 is a one-wavelength ring resonator composed of the ring-shaped transmission line 1.

Regarding the resonator configured as described above,
The operation will be described below. The one-wavelength ring resonator has a feature that it has no ground point and little loss, and its resonance frequency is determined so that the electrical length of the ring-shaped transmission line 1 becomes one wavelength, that is, 360 °.

[0005]

However, in the above-mentioned conventional structure, since the electrical length of the transmission line is 360 °, it is difficult to reduce the size of the entire resonator, and there is no position for adjusting the electrical length of the transmission line to cause resonance. There is a problem that it is difficult to adjust the frequency.

The present invention solves the above conventional problems, and an object of the present invention is to provide a resonator which has a low loss, is smaller in size than the conventional example, and is easy to adjust.

[0007]

In order to achieve this object, the present invention has a structure in which a grounding capacitance having a different capacitance value is connected to two points that equally divide the ring-shaped transmission line.

[0008]

According to the present invention, a part of the ring-shaped transmission line is replaced by two anti-grounding capacitances having different capacitance values, and the line length is shortened from one wavelength, that is, 360 ° to realize a compact resonator. The resonance frequency of the resonator can be easily adjusted by adjusting the capacitance to ground.

[0009]

【Example】

(First Embodiment) A first embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view of a resonator according to the first embodiment of the present invention. In FIG. 1, 11 is a ring-shaped transmission line composed of a strip line or a microstrip line. Reference numerals 12 and 13 denote first and second anti-grounding capacitances based on lumped constants, which are provided inside the ring-shaped transmission line 11. Reference numeral 14 is a ring-shaped resonator, which is composed of the ring-shaped transmission line 11 and the first and second capacitances to ground 12 and 13 described above.

The ring-shaped resonator 1 configured as described above.
The operation of No. 4 will be described. Ring-shaped transmission line 1
By connecting anti-grounding capacitors 12 and 13 having different capacitance values to two points that divide 1 equally, a part of the ring-shaped transmission line 11 can be replaced by the anti-grounding capacitance, and the line length of the entire resonator can be increased. Can be significantly downsized. The first and second
Since different values can be used as the capacitance values of the anti-grounding capacitors 12 and 13, the degree of freedom in design is increased and the resonance frequency can be easily adjusted.

In this embodiment, the capacitance to ground 12, 13 is provided.
Is a fixed capacitance element, but may be a variable capacitance element.

As described above, according to the present embodiment, by connecting the grounding capacitances 12 and 13 having different capacitance values to two points that equally divide the ring-shaped transmission line 14, the resonator line length can be reduced from the conventional example. The size can be further reduced, and the resonance frequency can be easily adjusted.

(Second Embodiment) A second embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 is a plan view of a resonator according to the second embodiment of the present invention. In FIG. 2, reference numeral 21 is a ring-shaped transmission line composed of a strip line or a microstrip line. Reference numerals 22 and 23 denote first and second stubs having different line lengths, which are provided inside the ring-shaped transmission line 11. Reference numeral 24 is a ring-shaped resonator, which is composed of the ring-shaped transmission line 21 and the first and second stubs 22 and 23 as described above.

The ring-shaped resonator 2 configured as described above
The operation of No. 4 will be described. First of all, the first and second stubs 22 and 23 are open at their tips, and are capacitive at the resonance frequency. However, since their line lengths are different, their equivalent capacitance values are also different. Next, from two points that divide the ring-shaped transmission line 21 into equal parts, the ring-shaped transmission line 2
By connecting the stubs 22 and 23 to the inside of 1, respectively, a part of the ring-shaped transmission line 21 is connected to the stubs 22 and 23.
Can be replaced with, and the line length of the entire resonator can be significantly reduced. Further, since it is not necessary to make the line lengths of the first and second stubs 22 and 23 the same, one side or both sides of the stub can be freely trimmed, the degree of freedom in design is increased, and the resonance frequency can be easily adjusted. Become.

As described above, according to the present embodiment, by connecting the stubs 22 and 23 having different line lengths to two points that equally divide the ring-shaped transmission line 24, the resonator line length can be made significantly larger than the conventional one. The size can be reduced and the resonance frequency can be easily adjusted.

(Embodiment 3) A third embodiment of the present invention will be described below with reference to the drawings.

FIG. 3 is a plan view of a resonator according to the third embodiment of the present invention. In FIG. 3, the components numbered 21 to 23 are the same as those in FIG. 3 is different from the configuration of FIG. 2 in that the first and second anti-grounding capacitances 31 and 32 based on the lumped constant are connected to the first and second stubs 2.
This is the point provided at the tip of Nos. 2 and 23.

The ring-shaped resonator 3 configured as described above
The operation of No. 3 will be described. The first anti-grounding capacitance 31 is connected to the tip of the first stub 22, and the second
By connecting the second grounding capacitance 32 to the tip of the stub 23, the line length of the two stubs 22 and 23 and the capacitance values of the two grounding capacitances 31 and 32 are adjusted to adjust the resonance frequency. be able to. The rest of the operation is the same as in the second embodiment, and will be omitted.

As described above, according to this embodiment, the stubs 22 and 23 having different line lengths are connected to two points that equally divide the ring-shaped transmission line 33, and each stub 2 is further connected.
By connecting the anti-grounding capacitances 31, 32 to the tips of 2, 23, the resonator line length can be made much smaller than in the past and the resonance frequency can be easily adjusted.

(Embodiment 4) A fourth embodiment of the present invention will be described below with reference to the drawings.

In FIG. 4, the components numbered 21 to 23 are the same as those in FIG. 4 is different from the configuration in FIG. 2 in that a varactor diode 41 that changes the capacitance value by an applied voltage is provided at the tip of the second stub 23, and a DC voltage application terminal 42 is provided in the ring-shaped transmission line 21. It is a point.

The ring-shaped resonator 43 configured as described above
The operation will be described below. First, the cathode terminal of the varactor diode 41 is connected to the tip of the second stub 23, and the anode terminal is grounded. Next, from the DC voltage application terminal 42 to the ring-shaped transmission line 21 and the second stub 2
By applying a DC voltage to the cathode terminal of the varactor diode 41 via 3, the varactor capacitance is determined by the DC potential of the varactor diode 41. The resonance frequency can be statically adjusted by laser trimming the length of the first stub 22, and the dynamic adjustment of the resonance frequency in actual use can be performed by the DC potential applied to the varactor diode 41. This is possible by changing the varactor capacity. Note that other operations are omitted because they are similar to those of the second embodiment.

As described above, according to this embodiment, the stubs 22 and 23 having different electric lengths are connected to two points that equally divide the ring-shaped transmission line 43, and the varactor diode 41 is provided at one end of the stubs 22 and 23. The resonance frequency can be adjusted statically or dynamically by connecting the.

In the second, third and fourth embodiments, the first and second stubs 22 and 23 are provided inside the ring-shaped transmission line, but one or both stubs are provided outside. Good. Although the ring-shaped transmission line is circular in the first to fourth embodiments, it may be an arbitrary closed curve.
Although the variable capacitance element is the varactor diode 42 in the fourth embodiment, it goes without saying that the varactor diode 42 may be any variable capacitance element.

[0027]

As described above, according to the present invention, by connecting the anti-grounding capacitance to each of the two points that equally divide the ring-shaped transmission line, an excellent resonator which is smaller than the conventional example and whose resonance frequency can be easily adjusted is provided. It can be realized.

[Brief description of drawings]

FIG. 1 is a plan view of a resonator according to a first embodiment of the present invention.

FIG. 2 is a plan view of a resonator according to a second embodiment of the present invention.

FIG. 3 is a plan view of a resonator according to a third embodiment of the present invention.

FIG. 4 is a plan view of a resonator according to a fourth embodiment of the present invention.

FIG. 5 is a plan view of a conventional resonator.

[Explanation of symbols]

 11 Ring Transmission Line 12 First Ground Capacitance 13 Second Ground Capacitance 14 Ring Resonator 21 Ring Transmission Line 22 First Stub 23 Second Stub 24 Ring Resonator 31 First Ground Capacitance 32 Second capacitance to ground 33 Ring-shaped resonator 41 Varactor diode 42 DC voltage application terminal 43 Ring-shaped resonator

Claims (5)

[Claims] 1. A resonator comprising a ring-shaped transmission line and two anti-grounding capacitors having different capacitance values which are respectively connected to two points equally dividing the ring-shaped transmission line. 2. A resonator in which a ring-shaped transmission line and stubs having different lengths are provided inside the ring-shaped transmission line at two points that equally divide the ring-shaped transmission line. 3. The resonator according to claim 2, wherein one or both stubs are provided outside the ring-shaped transmission line. 4. The resonator according to claim 2 or 3, wherein a capacitance to ground is provided at each tip of the stub. 5. The resonator according to claim 1 or 4, wherein a variable capacitance element is used as a capacitance to ground.