JPS5986305A - Switching device of transmission line - Google Patents

Abstract

PURPOSE:To keep the impedance constant over a wide band by providing a slope to an outer conductor so that a gap at one end is narrow and a gap having a contact is wide. CONSTITUTION:When a current flows to an exciting coil 28, the tips of strip center conductors 21, 22 made by a magnetic substance are magnetized to different polarity. Then, the tips of the strip center conductors 21, 22 are attracted or repulsed by magnets 25, 26 of opposite polarity. The center conductors 21, 22 are brought into contact with a microstrip distribution circuit resistance thin film type attenuator 18 or 19. That is, the strip center conductors 21, 22 are connected electrically via the resistance thin film type attenuator. Even if the exciting current is interrupted, since the attractive or repulsive force by the magnets is storonger than the elastic force of the conductors 21, 22, the electric connection is kept. Since the shape of the outer conductor 15 is designed to be wider at the part of moving contact, the impedance of the transmission line is kept constant.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transmission line switching device, and particularly to a sieve frequency transmission line switching device that maintains a constant characteristic impedance even when switching transmission lines.

Broadband transmission line switching from DO to SHF bands is described in US Pat. No. 3,500,263, and a 9% distributed circuit resistive film attenuator is described in US Pat. No. 3,227,975.

A variable attenuator using this transmission line switching method and a distributed circuit resistive thin film attenuator has a constant attenuation of 1. It will have .

Conventional variable attenuators have structures shown in FIGS. 1 to 3N. - i.e. earth conductor l
The tip of the strip center conductor 2 extending from one end (not shown) of the strip center conductor 2 is sandwiched on both sides by an insulating guide member 3, and the guide member 41'3 is inserted into a sliding device f? 24
By moving the strip center conductor 2 from side to side, the center body 2 of the strip is bent, and the tip of the strip center conductor 2 (I
The leading edge of the strip center conductor 2 was brought into contact with the through conductor 5 side or the distributed circuit resistor thin film 6 side provided in J, and the transmission line was switched while maintaining the characteristic impedance constant. Note that the reference numeral 7.8 indicates a dielectric material.

The switching of the transmission line used in this variable attenuator is
It is based on the following principle. In Fig. 4, the strip center conductors 9 are arranged at equal intervals between the parallel ground conductors 10 and 11, and the long cross section of the strip center conductor 9 is perpendicular to the ground conductors 10, 11 and C. It becomes. In such a case, the electromagnetic field is
．． 11 and the ground conductor 10.1 of the strip center conductor 9
Concentrate on the part facing 1, that is, the edge part. Now, assuming that the distance between the earth 7J body 10 and 11 is the length of the long sleeve of the cross section of the central body 9 in the strip, that is, the width is W, then the impedance of the characteristic 1' shown in the 41st circle 1 is! Even if the strip center conductor 9 is moved horizontally in parallel, the edge n of the strip center conductor 9
The electromagnetic field distribution for B is the same as that of B, and its characteristic impedance changes by 1 (-no change).

By the way, in changing the transmission line of the FtJ variable attenuator shown in FIGS.
It is determined by the ratio of the width of the ground conductor 1 to the distance between the ground conductors, that is, the distance in the long axis direction of the cross section of the strip center conductor 2. For example, in order to miniaturize a variable attenuator, Conductor 20 width and ground conductor 1
There is a need to reduce the distance between Therefore, the distance between the strip center conductor 2 and the ground conductor 1 is set such that the width of the strip center conductor 2 is w = 2.3. , = wmm, when the distance between ground conductors h = 2.75 mm (2,75-2
, 3)/2"" 0.2.25 mart, and requires strict processing accuracy and π11 precision, and these errors increase the characteristic VC at high frequencies. J: +, +: The problem of not being able to see the effects was rare. Also, when we want to change the thickness of the strip center conductor 2, we have to change the distance between the ground conductors, so we have to make the ground 7h and the body IVC uneven, and the force 11 is 4', 14. prisoner 411
There was a drawback.

In No. 5174, the strip center conductor 12 is arranged 6Vc between the parallel ground conductors 13.14, and the short axis of the cross section of the strip center conductor 12 is perpendicular to the ground conductor 13.14 by 1p. There's Tonatsuya.

That is, the central conductor surface 1.2a of the strip is parallel to the ground conductor 13. In this case, the electromagnetic field is distributed between the ground conductor 13.14 and the strip center conductor surface 1 opposite the ground conductor 13.14 of the strip center conductor 12.
2a, respectively. Now the strip center conductor 12
is placed in the center of the seven earth conductors 13.14, the distance between the earth conductors 13 and 14 is b, the length of the long sleeve of the cross section of the strip center conductor 12, that is, the width is wl, and its thickness is t. Then, the characteristic impedance tj shown in FIG.
: Determined by the ratio of w/b and t/b. In order to maintain the zero impedance at 50Ω, which is the same as explained in FIG.
Distance b = 2mTrL from the center conductor surface 1 of the filter strip, thickness t = 0.125mm of the strip center Nf body 12
The distance between 2a and ground conductor 13 is (2-0,125)/
2 = 0.9375 tomo, which is 0.225 as shown in Figure 4.
It becomes wider than mm. Therefore, it is suggested that the precision of processing accuracy and assembly accuracy may be reduced. Even if the strip center conductor 12 is moved vertically in parallel, the strip center conductor 12 and the ground conductor 12 are connected to each other as long as the magnetic impedance is determined by the distribution of the electromagnetic field between the strip center conductor surface 12m and the ground conductor 13, for example. 1
If the distance 1 to 3 is kept constant at 11'N, the distribution of the electromagnetic field will be similar to y, and its characteristic impedance will not change. In other words, the characteristic impedance remains constant.

In the present invention, when switching a transmission line, an electromagnetic field concentrated at the edge Fl1 minute VC of the strip center two bodies arranged at equal intervals between the parallel ground conductors shown in FIG. Depending on the movement, v times 1/
i#? :The characteristic impedance is maintained constant because the transmission is maintained constant.
By using a structure that maintains y constant despite the movement of the center conductor of the tube, the electromagnetic effect between the ground and the body facing the center conductor of the strip is distributed in the same way as y.
It is an object of the present invention to provide a transmission line switching device that eliminates the above-mentioned drawbacks by using a transmission line switching method that maintains a constant characteristic impedance. For this reason, the transmission line switching device of the present invention is arranged so that the gap at one end is narrow and the gap at the other end is wide, and the transmission line switching device is inclined and faces each other. ! i! The first one extending in the direction. an outer conductor having the same potential and having a second inner wall, one end of which is disposed between the inner wall of the one end in alignment with the axis, and the other end of the outer conductor is movable back and forth between the inner wall of the other end; , and at least the other end of the central conductor is made of a magnetic material; J attached to the second valley 9 and capable of contacting the other end of the front 1] middle 0 conductor
, a first microstrip line having a ψ point part and +
1", 2 (1) microstrip line), an excitation means disposed outside the outer conductor and magnetizing the magnetic part of the central conductor, and a ridge line on the first microstrip line side. 1.1: The magnetic material of the center conductor is placed in the north pole of the second microstrip line (in the case of Lull, it is arranged to be the south pole, and is magnetized by the excitation means). The present invention is characterized in that it includes a magnet for contacting and holding the contact point of the first microstrip line or the second microstrip line.Hereinafter, it will be explained with reference to the drawings from No. 61 No. 1 onwards. do.

FIG. 6 is a schematic internal sectional view for explaining the present invention, and FIG.
Figure (1) or duty is the 6th! 8 is a cross-sectional view of a variable attenuator according to an embodiment of the present invention, and FIG. 9 is a microstrip distributed circuit resistor thin film attenuation diagram. Figure 10 is a perspective view of the microstritz through element, Figure 11 is a diagram illustrating the operation of the variable attenuation filter shown in Figure 8, and Figure 12 is a perspective view of the device. 13 is a cross-sectional view of another embodiment of the variable attenuator using the present invention, FIG. The figure shows a partial cross-sectional view.

In the internal schematic cross-sectional view of FIG. 6 for explaining the present invention, the outline of the transmission line switching 4 station according to the present invention is shown as a variable range [U'+] in which two transmission line switching stations are connected in series, excluding the excitation means. Illustrated. The earth conductor 15, which is an external conductor, has a narrow gap at one end and a first inner wall 15a and a second inner wall 15b which are inclined so that the gap at one end is wide. 1゜The second inner walls 15at15b each have an opening (st).゛1-A rectangular cross-sectional force supervisory conductor 16 is provided on the central axis inside the 1-st conductor 15. , the above) One end of the IJ tube center conductor 16 is supported by the -f'+4 part of the ground conductor 15 (the 8th
(see figure) is fixed by a circular strip center conductor 17.

The other end of the strip center conductor 16 is a free end of a conductive material made of at least a magnetic material. 61 of the inner wall where the ground conductor 150 gap is the widest. At the Wd end face q at the free end of the front R strip center conductor 15, there is a microstrip distributed circuit resistance thin-shaped attenuation 8i+18 which is the first microstrip line and a microstrip which is the second microstrip line. Each through element 19 is
t is provided.

The strip center conductor 15 has a flexible opening 3, and the magnetism at the tip of the strip center conductor 16 is returned to the center 75 by an excitation means not shown in FIG. 8R11G 1.8 side,
Alternatively, it is bent and electrically connected to the microstrip through element 19@1. At this time, the strip rp I17 conductor surface of the strip center conductor 16 and the ground conductor 15
1st. The distance from the second 8M 15a, 15b is the same as that of the first 8M 15a, 15b at any position of the IO conductor 16 in the IJ tube. Since the second inner walls 15a and 15b are sloped, the 41 views are the same.

Figure 7 (I) to ω are arrows A-A and B-11 in Figure 6.
．． 0-0. In the same figure (1), since the circular strip center conductor 17 is fixed at the center of the ground conductor 15, the electromagnetic field is connected to the outer periphery of the circular strip center conductor 17. The distribution is concentrated between the opposing earth shield bodies.

In the same figure (II), since the strip center conductor 16 is located at the center of the ground conductor 15, the electromagnetic field is transmitted along the length of the rectangular strip center conductor 16, that is, at the ground conductor facing the strip center conductor surface. The distribution is concentrated at intervals.

The same figure (In ID, the strip center conductor 16 has a deviation and is shifted from the center of the ground conductor 17, so the electric current (+1
The field is between the rectangular strip center conductor 16 and the strip center 7! The I-body 16 is distributed in a concentrated manner between the ground conductors that are close to each other. However, in reality, an electromagnetic field is generated and distributed between the ground conductors on the opposite side and between the upper and lower edge parts of the strip center 25 body 16 and the ground conductor, so the spacing is wider than the design value of the microstrip line. It is common to take

In the figure ω, the dielectric 20 is inserted between the strip center conductor 16 and the ground conductor 15, so the electromagnetic field is
The distribution is concentrated between the IJ center conductor 16 and the ground conductor.

Here, the strip center conductor 16, the circular strip center conductor 17, the microstrip distributed circuit resistance thin film type damping pin 18, the microstrip through element 19, etc. are -1-
Together with the conductor 15, the dimensions are determined and arranged to satisfy a characteristic impedance of a predetermined value.

Therefore, the distribution of the electromagnetic field as described above is exactly the same even when the rectangular strip center conductor 16 is moved from the microstrip distributed circuit resistance thin film attenuation band 18 side to the microstrip through element 19 side. Therefore, switching can be performed without changing the characteristic impedance.

FIG. 8 shows a cross-sectional view of a variable attenuation mirror according to an embodiment of the present invention, with reference numeral 15.15a in N.

15b, 17 to 19 correspond to those in FIG.

Reference numerals 21e and 22 indicate strip center conductors having a rectangular cross section, which correspond to the strip center conductor 16 in FIG. Therefore, 196,512 bodies 21.22
The tip of the holder is made of at least a metal wire made of magnetic material.

A microstrip distributed circuit resistive thin film attenuator 18 and a microstrip through element 19 are provided in the center of the ground conductor 15V3, respectively. As shown in FIG. 9, the microstrip distributed circuit resistor thin film 32 is attached to the surface of a dielectric 31, and a ground conductor 33 is attached to the back of the dielectric 31. It is being In addition, code 34
．． 35 is a ground conductor, and 25 is a magnet.

The microstrip through element 19 has a microstrip through conductor 2 on the surface of the dielectric 36 as shown in FIG.
4 is attached, and a ground conductor 37 is attached to the back side of the dielectric body 36.
The thickness of the dielectric material 31 is made to be the same as the thickness of the dielectric material 31 shown in FIG.

For example, the eighth (second
) 25 and 26 having the illustrated polarities are respectively arranged via ground conductors 33 and 37, which are electrically connected to the ground conductor 15 and connected to the first. Second inner wall 15a.

It has the same potential as 15b.

An excitation coil 28 wound around a zebin 27 is provided at the center of the outer 11y of the earth conductor 15, and a strip center conductor 21, 22 made of a magnetic material is provided depending on the direction of the excitation current flowing through the excitation coil 28. Magnetize the tip of the A reciprocal attraction occurs between the tip of the magnetized strip center conductor 21.22 and the magnetic pole of the magnet 25°26, causing the strip center conductor 21.22 to bend,
The tips of the strip center conductors 21 , 22 are brought into contact with either side of the microstrip distributed circuit resistive film attenuator 18 or the microstrip through element 19 . At this time, as explained above, the distance between the bent strip center conductor surface, for example, the strip center conductor surface of 21, and the ground conductor 33 and the first inner wall 15a, or the distance between the ground conductor 3
7 and the second I'l wall 15b are formed to be equal in distance, so that the characteristic impedance is maintained constant. The same goes for the strip center conductor 22 in the style of A11, and the impedance (/l) is also kept constant.Moreover, since the thicknesses of the inductors 31 and 36 are the same, the effect of the excitation coil 28 is Therefore, no matter how many times the strip center conductor 21, 22 contacts the microstrip distributed circuit resistance thin film attenuator 18 side, or the microstrip through element 19 ft11, the distance tj to the ground conductor 33 or 37 remains constant. It is maintained,
Therefore, the characteristic impedance is also always constant.

Next, the operation of the variable range device shown in FIG. 8 will be explained using FIG. 11. In the same figure - C1 code 17 to 1
9 corresponds to that in FIG. 6, 21, 22° 25.26.
28 corresponds to that in FIG.

The excitation coil 28 is originally wound around the center of the ground conductor 15, but is drawn below the magnet 26 to make the explanation easier to understand.

An excitation current flows through the terminal 38.39 VC DC power supply line 28 of the assisting machine 28 in the direction of the arrow shown in the figure.

The excitation current flowing in this direction causes the excitation coil 2 to
The tip of the strip center conductor 22 made of a magnetic material disposed inside the magnetic material is magnetized to the north pole, and the tip of the strip center conductor 21 made of a magnetic material is opposite to the strip center conductor 22. Therefore, it is magnetized to the south pole. Due to this magnetization L-, the tip of the strip center conductor 21 is attracted to the N pole of the magnet 25, and
A repulsive action occurs at the 8 poles of the magnet 26, and the strip center conductor 21 is bent, and the strip center conductor 2]
The tip of the microstrip distributed circuit resistor makes contact with a thin film type damping cap 18. On the other hand, at the tip of the strip center conductor 22, an attraction action occurs at the 8 poles of the magnet 25, and a repulsion action occurs at the N pole of the magnet 26, and the strip center conductor 22 is bent.
The tip of 2 makes contact with the 11 microstrip distributed circuit resistor model attenuator 18. That is, the strip center conductor 21 and the strip center conductor 22 are connected to the microstrip distributed circuit resistance thin film type reduction i! : Electrically connected via ÷18. Even when the excitation current flowing through the excitation coil 28 is cut off, the attractive force with which the N and S poles of the magnet 25 attract the tips of the strip center conductor 21 and the strip center conductor 22, respectively, is as follows.
Since the elastic force is greater than the elastic force of each strip center conductor 21, 22 which is being bent, the electrical connection between the strip center conductor 21 and the strip center conductor 22 via the microstrip distributed circuit resistive thin film attenuator 18 is maintained. Ru.

Next, the terminal 38 of the excitation coil 28. When the negative (・In addition, the tips of the strip center conductors 22 are magnetized with the tiS poles.As a result, a repulsive force is generated between the tips of the strip center conductors 21 and 22 with the N and 8 poles of the magnet 25, and the microstrip distribution The electrical connection between the strip center conductor 21 and the strip center conductor 22 via the circuit resistor thin film type conductor 18 is released. While being repulsed by the N pole, the magnet 26
An attractive action occurs between the 8 poles, the strip center conductor 21 is bent, and the tip of the strip center conductor 21 comes into contact with the microstrip through element 19. Similarly, the tip of the strip center conductor 22, which is magnetized to 8 rc poles, is repelled by the 8 poles of the magnet 25, and an attractive action is generated between it and the ON pole of the magnet 26, causing the strip center conductor 22 to bend. The tip of the center conductor 22 makes contact with the microstrip through element 19. That is, by passing an excitation current in the opposite direction to the excitation coil 28, the strip center conductor 21 and the strip center conductor 22 are electrically connected again via the microstrip through element 19. Then, as explained above, the excitation current flowing through the excitation coil 28 is cut off, and a) the S and N poles of the magnet 26 are located 6 points ahead of the strip center conductor 21 and the strip center conductor 22;
Since the suction force that attracts each portion is greater than the elastic force of each bent strip center conductor 21, 22, the electrical connection between the strip center conductors 21 and 22 is maintained.

Here, when the strip center conductor 21 and the strip center conductor 22 are electrically connected via the microstrip distributed circuit resistive thin film attenuator 18, the microstrip distributed circuit resistive thin film attenuator 18 has After attenuating the power of the attenuation amount, the strip center conductor 2
1 to the strip center conductor 22 or vice versa. Further, when the strip center conductor 21 is electrically connected to the strip center conductor 22 via the microstrip through element 19, it is possible to transfer the transmitted power from the strip center conductor 21 to the strip center conductor 22 or vice versa without attenuating the transmitted power. 1E force is transmitted to.

In the above explanation, the transmission lines are switched in pairs, but it goes without saying that only one of the transmission lines can be switched.

FIG. 12 shows a sectional view of another embodiment of the variable attenuator according to the present invention, and FIG. 8 corresponds to one in which the variable attenuator shown in FIG. .

Reference numbers 15.15a, 15b, 17 correspond to those in FIG. 6, and numbers 18.19, 27 to 30 correspond to those in FIG. Reference numerals 40, 41, and 42 are strip center conductors whose tips are made of at least a magnetic material, and 43 is a strip center conductor holder J1. The strip center conductor 41 is riveted to the strip center conductor holder 431 as shown in FIG.

Therefore, by appropriately combining the directions of the excitation currents flowing through the two excitation coils 28, the strip center conductor 4
0.41.42 is microstrip distributed circuit resistance thin film type reducer 18 or microstrip through element 19
It is rc-connected, and the attenuation of the transmitted power, l and l, can be varied while maintaining the characteristic impedance constant.

No. 141A is a portion Nl of another embodiment of the inner wall of the ground conductor.
The i-plane t:'-1, the code 15.17 corresponds to that in FIG. 6, and 18, 19, 21, 22.29 are the 81st! ;
It corresponds to 4. 15'o represents the first t wall, 1 s' b tJ2 represents the second inner wall, and the 6th
The first of the smoothly sloping curves shown in Figure 8 and 1.
It has been experimentally confirmed n3 that there is no problem in replacing the second inner walls 15a and 15b with a shape that can be easily machined. It is also possible to switch the practical soil transmission line using the first inner wall 15'a and the second inner wall 15'b having approximate shapes as shown in No. 141 and J.

In the above description, the magnets 25 and 26 are not limited to the rod-shaped magnets shown in the drawings, but a plurality of magnets may be used to provide the polarities shown in the drawings. It goes without saying that all the poles n of the magnets 25 and 26 may be opposite poles t'bct.

As described above, according to the present invention, the distance between the strip center conductor surface of the strip center conductor having a rectangular cross section and the inner wall of the ground conductor is maintained constant, and switching of the transmission line is performed. Since the distance between the strip center conductor and the ground conductor is close, the machining accuracy and assembly M accuracy can be improved.
This makes it possible to create a more sophisticated transmission line switching device with less effort required. The transmission line can be switched with the characteristic impedance kept constant, and the switching means has sufficient isolation and isolation loss at high frequencies.

The strip center conductor can be switched without contact depending on the direction of the excitation current flowing through the excitation coil when switching the transmission side path.
Switching operation becomes stable.

Furthermore, by using the transmission line switching device of the present invention in a variable attenuator, it is possible to attenuate the attenuation constant over a wide range of frequencies from DC to high frequencies.
This results in a variable attenuator with excellent r'i characteristics.

[Brief explanation of drawings]

Figure 1 is a partial cross-sectional view of a conventional transmission line switching device.
is viewed from the X-X arrow in Figure 1.
Y-arrow view, Figures 4 and 5- are l-chronochronal inbees. Principle explanation for explaining dance 1 No. 1% No. 61 J explains the present invention The internal schematic cross section for l'J (Kyo, No. 71 flash or 1lJ) is; \r, each arrow in Figure 6 Look+
An explanatory diagram explaining the distribution of the +1 magnetic field, No. 8 is a sectional view of a variable attenuation type according to an embodiment of the present invention, and No. 9 is a perspective view of a microstrip distribution circuit resistive thin film type attenuator. ,
No. 101-1 is a perspective view of a microstrip through element, FIG. 11 is an explanatory diagram illustrating the variable attenuation type m1 operation shown in FIG. A sectional view of another embodiment, FIG. 13 is a perspective view of a strip center conductor holder, and FIG. 14 is a partial sectional view of another embodiment of the inner wall of the ground conductor. In the figure, 15 is a ground conductor;
15a, 15'a are first inner walls, 15b, 15'b are second inner walls, 16 is a strip center conductor, 17 is a circular strip center conductor, 18 is a microphone strip distributed circuit resistor thin film attenuator, 19 is a strip center conductor; Microstrip through element, 20 is a dielectric, 21.22 is a strip center 26 is a magnet, 27 is a FJZ pin, 28 is an excitation coil, 29
．． 30 is an input/output plug, 31 is a dielectric, 32 is a microstrip distribution circuit (((anti-thin film, 33 to 35 FJ,
a ground conductor, 36 a dielectric, 37 a ground conductor, 38.
39 is a terminal, 40 to 42 are strip center conductors, 4
3 each represent a strip center conductor holder. Patent applicant: Anritsu πwoki Co., Ltd. Figure 1 Figure 152 Figure 4 i'I5U7J 114;4'); Figure 6 (I[) (IV)24'58
Go to Figure 9'S10 Figure 11

Claims (1)

[Claims] Q: 'jThe gap at one end is narrow and the gap at the other end is wide.
an outer conductor O11 having an inner wall at the same potential; one end thereof is disposed between the inner walls of the one end portion in accordance with the Inl+ gland, and the other end is capable of passing between the inner walls of the other end ttls; , and at least the other end is '6f
a central conductor (a) made of an i-type substance; 2nd each 8
a first microstrip line 01 and a second microstrip line 01 each having a contact portion that can be reached at the center conductor (A) and can contact the other end of the center conductor (A); disposed outside the outer conductor OrJ; and excitation means (c) for magnetizing the magnetic part of the central conductor (g); the first microstrip line 0 has an N pole on the eno side and the second microstrip line 0 has an S pole on the wharf side; The magnetic material portion of the center conductor (a) magnetized by the excitation means is repelled and attracted, and the first microstrip line θ or the second microstrip line is OLI contact 1M5K magnet for holding contact (
A transmission line switching device comprising (c) and (c).