JPH09214211A - Contactless coupling circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize the circuit at a low cost with an excellent workability that couples input and output signals in terms of DC contactless. SOLUTION: The circuit uses a coupling conductor 4 couples contactless other terminal of an input strip line 6 formed to one side 2a of a dielectric board 2 whose one terminal connects to an input connector 5 and other terminal of an output strip line 8 whose one terminal connects to an output connector 7 via an insulation board 3, and an ground circuit 9 is formed to the other side 2b of the dielectric board 2. The length of the coupling conductor 4 and the distance between the centers of the other terminals of the input and output strip lines 6, 8 are selected nearly the same as 1/4 of a wavelength λg with respect to the operating frequency of the dielectric board 2 and the other ends of the input and output strip lines 6, 8 are coupled while being somewhat overlapped respectively by the coupling conductor 4 via the insulation board 3 contactless in terms of static capacitance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-contact type coupling circuit capable of non-contactly transmitting a high frequency input signal to an output side, and more particularly to a phase shifter using the non-contact type coupling circuit. The present invention relates to a non-contact type coupling circuit which is constructed and has good workability when the beam tilt angle of an array antenna is continuously changed.

[0002]

2. Description of the Related Art Conventionally, various types of phase shift circuits for continuously changing the phase of a high frequency signal have been known, but a typical example is a line stretcher system formed by a coaxial tube. There is. This phase shift circuit has a structure in which the outer conductor and the inner conductor of the coaxial waveguide are slid on each other.
By continuously changing the lengths of the inner and outer conductors of the coaxial waveguide, the phase of the high frequency signal is continuously changed.

[0003]

However, since the inner and outer conductors of the coaxial tube are slid on each other, there is a problem in that noise and intermodulation are caused by poor contact. Also, when changing the beam tilt angle of the array antenna continuously, it is necessary to connect a line stretcher for each cable that feeds each element and finely adjust the length of each element, resulting in poor workability and man-hours. However, there is a problem that the cost increases due to increase in

The present invention has been made in view of the above points, and an object thereof is to solve the above-mentioned problems, to couple input and output signals in a direct current non-contact manner, and to continuously change the phase, and It is to provide a non-contact type coupling circuit which has good workability and can be realized at low cost.

Another object of the present invention is to provide a non-contact type coupling circuit having good workability when the beam tilt angle of the array antenna is continuously changed.

[0006]

SUMMARY OF THE INVENTION The above-mentioned problem is that an input-side strip line and an output-side strip line formed on the front surface of a dielectric substrate having a ground circuit formed on the back surface are separated by an insulator from the input-side strip line and In a non-contact type coupling circuit for coupling using a coupling conductor insulated from the output side strip line, the length of the coupling conductor is substantially equal to ¼ of the wavelength λg on the coupling conductor corresponding to the frequency used, A non-contact coupling circuit is characterized in that the impedance of the coupling conductor viewed from the input side strip line is substantially equal to the impedance of the coupling strip conductor viewed from the output side strip line.

According to the structure of the first aspect, the high frequency signal input from the input side strip line does not contact between the other end of the input side strip line and the other end of the output side strip line. Can be capacitively coupled and can be transmitted to the output side with low loss.

According to the second aspect of the present invention, the high-frequency signal input from the input side strip line is not in contact with the other end of the input side strip line and the output side strip line, and is capacitive. Is transmitted to the output side stripline in the shape of a semi-circle by the rotating coupling conductor coupled to
Here, the high frequency signal is equally distributed to the output terminals at both ends of the output side strip line.

When the rotary coupling conductor is rotated around the other end of the input side strip line, the rotary coupling conductor and the semi-arc shaped output side strip line are coupled to each other. There is a relative difference in the distance to the output terminals at both ends. Therefore, the high frequency signal also has a relative phase difference. At the same time, this phase difference can be continuously changed.

[0010]

The signal from the input side strip line is partially reflected by the coupling portion (first coupling portion) between the input side strip line and the coupling conductor and transmitted to the coupling conductor. Further, it is partially reflected by the coupling portion (second coupling portion) between the coupling conductor and the output side strip line and transmitted to the output side strip line.

Since the load impedance at the first coupling portion and the load impedance at the second coupling portion are equal, the reflected wave at the first coupling portion and the reflected wave at the second coupling portion have the same amplitude.

Since the length of the coupling conductor is approximately ¼ of the wavelength λg in the coupling conductor of the operating frequency, the reflected wave of the first coupling portion and the reflected wave of the second coupling portion are the first coupling portion. , The phases are almost opposite to each other and cancel each other, and almost all the electric power from the input side strip line is transmitted to the output side strip line.

That is, according to the structure of claim 1, the input side strip line and the output side strip line are matched.

In the embodiment of the present invention, wherein the coupling conductor is rotatable, the signals at the output terminals at both ends of the output side strip line, which is a part of the circular arc, have the same amplitude, and the rotation angle of the coupling conductor is large. The phase of the signal at one output terminal is advanced and the phase of the signal at the other output terminal is delayed by the electrical angle corresponding to.

This electrical angle can be continuously adjusted by changing the rotation angle of the coupling conductor.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will now be exemplarily described in detail with reference to the drawings. (First Embodiment) FIGS. 1 and 2 are views showing a first embodiment of a non-contact type coupling circuit of the present invention. FIG. 1 is a perspective view thereof, and FIG. 2 is an input / output strip of FIG. It is explanatory drawing of the cross-sectional structure in the longitudinal direction of a line. 1 and 2, this non-contact type coupling circuit 1 is composed of a dielectric substrate 2 having a circuit formed of metal foil on both sides, an insulating plate 3, and a coupling conductor 4.

On one surface 2a of the dielectric substrate 2 having a thickness of about 1.6 mm, an input side strip line (characteristic impedance is about 50Ω) 6 having one end connected to an input connector 5 as an input terminal is formed. , And an output side strip line (characteristic impedance of about 50Ω) 8 having one end connected to an output connector 7 as an output terminal, and the other end 6 of each of the input and output side strip lines 6, 8.
The a and 8a are capacitively coupled in a non-contact manner by the coupling conductor 4 via the insulating plate 3 having a relatively small thickness. A ground circuit 9 is formed on the entire other surface 2b of the dielectric substrate 2.

The center distance between the other ends 6a and 8a of the input and output side strip lines 6 and 8 is defined by the coupling conductor 4
And the length of the coupling conductor 4 is made substantially the same as the center distance. The coupling conductor 4 slightly overlaps the other ends 6a and 8a of the input and output side strip lines 6 and 8, for example, about 0.08 λg, and the thickness of the coupling conductor 4 is about 0.2 mm. The insulating plate 3 is inserted for capacitive coupling.

Such a coupling conductor 4 is connected to the other end 6a,
By coupling between 8a without contact, the high frequency signal input from the input connector 5 can be transmitted to the output connector 7 side with low loss.

3 and 4 show the return loss characteristic diagram and the pass loss characteristic diagram with respect to the frequency of this embodiment by the solid line, and in the 37% band, -14 dB (standing wave ratio 1.5). And a loss value as low as 0.3 dB is obtained. Further, in FIG. 3, it can be seen that if the length of the coupling conductor 4 is changed, the matching frequency changes according to the length. That is, the broken line shows the case where the length of the coupling conductor 4 is longer and the dashed-dotted line shows the case where it is shorter than the solid line in the figure.

(Second Embodiment) FIG. 5 is a perspective view showing a second embodiment of the present invention. In FIG. 5, the non-contact type coupling circuit 11 includes a dielectric substrate 12 having a circuit formed of metal foil on both sides, an insulating plate 13, and a rotary coupling conductor 14.

On one surface 12a of the dielectric substrate 12, one end is connected to an input connector 15 serving as an input terminal, and an input side strip line (characteristic impedance is about 5).
0Ω) 16 and output connector 1 with both ends as output terminals
An output-side strip line (characteristic impedance of about 50Ω) 18 connected to 7a and 17b is formed.
The input and output side strip lines 16 and 18 are capacitively coupled in a non-contact manner, and the rotary coupling conductor 14 is rotatably arranged. A ground circuit 19 is formed on the entire other surface 12b of the dielectric substrate 12.

The rotary coupling conductor 14 has one end 14a.
Is rotated about the other end 16a of the input-side strip line 16, and its length is equal to 1 of the wavelength λg of the operating frequency.
It is formed almost the same as / 4. One end 14a of the rotary coupling conductor 14 is connected to the input side strip line 1
The other end 16a of 6 is slightly overlapped with, for example, about 0.08 λg, and the insulating plate 13 having a thickness of about 0.2 mm is inserted therebetween, and capacitively coupled in a non-contact manner.

On the other hand, the output side strip line 18 is
The distance between the center of the width of the line 18 and the center of the other end 16a of the input-side strip line 16 is a semi-circular shape (semi-annular ring) centered on the other end 16a having the same radius as the length λg / 4. Is formed in. Then, the rotary coupling conductor 1
The other end 14b of 4 is slightly overlapped with the semi-circular output side stripline 18, for example, about 0.08λg, and the insulating plate 13 having a thickness of about 0.2 mm therebetween.
Is inserted and capacitively coupled in a non-contact manner.

By connecting the rotary coupling conductor 14 between the other end 16a of the input side strip line 16 and the output side strip line 18 in a non-contact manner, a high frequency wave inputted from the input connector 15 is obtained. The signal is transmitted to the output side with low loss, and the signal is equally distributed to both output connectors 17a and 17b of the output side stripline 18.

Since the other end 14b of the rotary coupling conductor 14 is coupled in a non-contact manner so as to slide on the output side strip line 18, from this coupling portion, the output connectors 17a, 17b at the both ends. For each distance to
In addition to the relative difference, the high frequency signal also causes the relative phase difference. Therefore, by rotating the rotating coupling conductor 14, this phase difference can be continuously changed.

FIG. 6 shows a return loss characteristic diagram with respect to the frequency of this embodiment. In the band of 14.6%, −14 dB (standing wave ratio 1.5) is obtained. At the same time, FIG. 7 shows a pass loss characteristic diagram with respect to the frequency in this case, and the pass loss characteristic values of the high frequency signals I and II respectively output to both connectors 17a and 17b are exactly the same.

Note that the technique of the present invention is not limited to the technique in the above-described embodiment, and may be implemented by means of another aspect that achieves the same function, and the technique of the present invention can be variously modified within the scope of the above configuration. Can be changed or added.

[0029]

As is apparent from the above description, according to the non-contact type coupling circuit of the present invention, according to claim 1, the length of the coupling conductor and the center of each of the other ends of the input and output strip lines. The distance between them is the wavelength λ of the frequency used in the coupled conductor.
It is almost equal to 1/4 of g, and the other ends of the input and output strip lines are capacitively coupled through the insulating plate so that they are slightly overlapped by the coupling conductors. It is possible to combine the output signals in a non-contact manner in terms of direct current, to improve workability, and to realize at low cost.

With respect to claim 2, the wavelength λ at the frequency used.
One end of a rotary coupling conductor having a length substantially equal to 1/4 of g is disposed so as to rotate around the other end of the input side strip line, and is slightly overlapped with the other end of the input side strip line. In the same manner, capacitive coupling is performed via the insulating plate, while the output side strip line has a radius of ¼ of the wavelength λg in the rotary coupling conductor, and the other end of the input side strip line is the center. Is formed in a semi-circular shape, and capacitive coupling is performed through the insulating plate so that the other end of the rotary coupling conductor is slightly overlapped with the semi-circular strip line. It is possible to combine the input and output signals in a direct current contactless manner and continuously change the phase. The workability is good and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a perspective view showing a first embodiment of a non-contact type coupling circuit of the present invention.

FIG. 2 is a cross-sectional explanatory view in the longitudinal direction of the input and output side strip lines of FIG.

FIG. 3 is a return loss characteristic diagram with respect to frequency in the first embodiment.

FIG. 4 is a pass loss characteristic diagram with respect to frequencies of the first embodiment.

FIG. 5 is a perspective view showing a second embodiment of the non-contact type coupling circuit of the present invention.

FIG. 6 is a return loss characteristic diagram with respect to frequency in the second embodiment.

FIG. 7 is a pass loss characteristic diagram with respect to frequencies of the second embodiment.

[Explanation of symbols]

1,11,12,22 Non-contact type coupling circuit 2,12 Dielectric substrate 2a, 12a One side 2b, 12b The other side 3,13 Insulating plate 4 Coupling conductor 5,15 Input connector 6,16 Input side strip line 7, 17a, 17b Output connector 8, 18 Output side stripline 6a, 8a, 14b Other end 9, 19 Ground circuit 14 Rotation coupling conductor 14a One end λg On coupling conductor or rotation coupling conductor corresponding to frequency used wavelength

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yuko Saito 3-3-1 Marunouchi, Chiyoda-ku, Tokyo Inside Denki Kogyo Co., Ltd. (72) In-house Masayoshi Serizawa 3-3-1 Marunouchi, Chiyoda-ku, Tokyo Ki Kogyo Co., Ltd. (72) Inventor Hirokazu Tsunoda 3-3-1, Marunouchi, Chiyoda-ku, Tokyo Denki Kogyo Co., Ltd. (72) Inventor Yoshio Ebene 2-10-1, Toranomon, Minato-ku, Tokyo N-TE IT Mobile Communication Network Co., Ltd.

Claims (2)

[Claims] 1. An input side strip line and an output side strip line formed on the surface of a dielectric substrate having a ground circuit formed on the back side are insulated from the input side strip line and the output side strip line by an insulator. In the non-contact type coupling circuit for coupling using the coupling conductor, the length of the coupling conductor is substantially equal to ¼ of the wavelength λg on the coupling conductor corresponding to the operating frequency, A non-contact type coupling circuit, wherein the impedance of the coupling conductor is substantially equal to the impedance of the output side strip line viewed from the coupling conductor. 2. The coupling conductor is rotatable about a coupling portion with the input-side strip line, and the output-side strip line is a part of an arc about a rotation center of the coupling conductor. 2. The non-contact coupling circuit according to claim 1, wherein the output ends of the output side strip lines are provided at both ends of a part of the arc.