JP2722929B2 - Strip line - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a strip line used for a microwave circuit or a microwave antenna feed line.

[0002]

2. Description of the Related Art FIG.
FIG. 2 is a configuration diagram of a conventional stripline written based on the diagram shown in Japanese Patent Application Publication No. 2 (JP-A) No. 2; In the figure, reference numeral 1 denotes a triplate line ground conductor, 2 denotes a microstrip line ground conductor, 3 denotes a triplate line inner conductor, 4 denotes a microstrip line upper conductor, 5 denotes a dielectric substrate, 6 denotes a triplate line and a microstrip line. Is a conversion unit.

In this strip line, the inner conductor 3 of the triplate line is joined to the upper conductor of the microstrip line by a converter 6. In addition, the triplate line ground conductor 1 is short-circuited by the conversion unit 6, the triplate line ground conductor 1 and the microstrip line ground conductor 2 are set to the same potential, and the reflection at the conversion unit 6 is suppressed. In addition, the conductor 3 in the triplate line
And the dielectric substrate 5 on which the microstrip line upper conductor 4 is mounted is cut at the converter 6.

[0004]

In a conventional strip line, the dielectric substrate 5 is discontinuous in the conversion section 6, and the structure of the conversion section 6 between the triplate line and the microstrip line becomes complicated. There is little freedom in selecting the height of the inner conductor 3 and the microstrip line upper conductor 4 from the ground conductor, and the processing of the ground conductor short-circuited part of the microstrip line and triplate line converter 6 is complicated and economical. However, there are problems such as poor adjustment of the reflection characteristics at the converter 6 between the microstrip line and the triplate line.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and has a good reflection characteristic, a simple structure, and a conversion unit of a microstrip line and a triplate line which is easy to process. It is an object of the present invention to obtain a strip line having a large degree of freedom in selecting characteristic impedances of a microstrip line and a triplate line.

[0006]

In order to solve such a problem, a strip line according to the present invention is provided with a microstrip.
A lip line and a triplate line are connected
In the stripline, the above-mentioned triplate line has
One of the two ground conductors
Place the stripline ground conductor on the surface of the first dielectric substrate
The above microstrip line is shared as the provided conductor surface
As the upper conductor of the road and the inner conductor of the above triplate line.
The conductive strip conductor used by the second dielectric substrate
Of the microstrip line
The upper conductor, provided on the surface of the first dielectric substrate
Height from the conductor surface and the inner conductor of the triplate line
From the conductor surface provided on the first dielectric substrate surface
So that the height of the second
Above the microstrip line on a dielectric substrate of
For the conversion part of the inner conductor and the inner conductor of the triplate line
Here, the second dielectric substrate is bent. Ma
The upper conductor of the microstrip line and the upper conductor
In the conversion part of the inner conductor of the triplate line,
Two ground conductors of the triplate line are connected by conductors
Connect and short circuit, or the first having the conductor surface
A notch is provided in a part of the dielectric substrate, and
Turn the minutes back, and the two
The above-mentioned conductor surface, which is one ground conductor of the ground conductor, is connected to the other ground conductor.
Is short-circuited. Also, the above microstrip
Place the upper conductor of the line and the inner conductor of the triplate line above.
The same as the upper conductor and the inner conductor of the second dielectric substrate
Trapezoid formed on the surface, or, engaged against a rectangular conductor
Things. Further, the first dielectric substrate and the second
One or both of the dielectric substrates
It is a body film substrate .

[0007]

In the present invention, the microstrip line and the triplate line are connected to each other.
In a strip line configured in succession,
One of two earth conductors of the plate line
Body and the ground conductor of the microstrip line,
Shared as a conductor surface provided on the dielectric substrate surface,
The upper conductor of the cross strip line and the above-mentioned triple play
Conducted strip conductor used as the inner conductor of the transmission line
On the same surface of the second dielectric substrate, and the microphone
The first dielectric material of the upper conductor of the loss strip line
The height from the conductor surface provided on the substrate surface and the triple
Of the inner conductor of the gate line on the surface of the first dielectric substrate
The height from the conductor surface provided at
As described above, the microstress on the second dielectric substrate
Above the upper conductor of the lip line and the triplate line
In the conversion section of the internal conductor, the second dielectric substrate is bent.
Since geta, triplate line inner conductor and the ground conductor spacing, by selecting the distance of the microstrip line the upper conductor and the ground conductor freely, while maintaining the degree of freedom in characteristic impedance selection of each line, in a simple process, A strip line in which a triplate line and a microstrip line are mixed is obtained.

[0008] In the strip line according to the second aspect, the my line
The upper conductor and the triplate of the cross trip line
In the conversion part of the inner conductor of the line, the triplate
Two ground conductors of a line are connected by a conductor and short-circuited
Therefore, reflection at the conversion unit is suppressed.

According to a third aspect of the present invention, in the strip line,
The upper conductor and the triplate of the cross trip line
In the conversion part of the inner conductor of the line, having the conductor surface
A cut is provided in a part of the first dielectric substrate,
Fold back the notch to make the above triplate line
The conductor surface , which is one of the two ground conductors
Since the short-circuit to the other ground conductor, reflection at the converter was suppressed.
Press.

In the strip line according to the fourth aspect, the my line
Upper conductor of cross-trip line and above triplate line
The inner conductor of the second dielectric substrate and the upper conductor.
Beauty inner conductor and the trapezoidal formed on the same surface, or by joining a rectangular conductor to facilitate impedance matching between the lines.

In the strip line according to a fifth aspect , the first
One or both of the dielectric substrate and the second dielectric substrate
Is a bendable dielectric film substrate, so that a light-weight, low-cost, easy-to-process, and easy-to-mount strip line that can be easily mounted on a housing can be realized.

[0012]

[Embodiment 1] FIG. 1 is a configuration diagram of the strip line according to the first embodiment of the present invention. In FIG. 1, 1 is a ground conductor of a triplate line, 2 is a ground conductor of a microstrip line, 3 is an inner conductor of a triplate line, 4 is an upper conductor of a microstrip line, 5 is a dielectric substrate, 6 is a triplate line and a microstrip. It is a conversion part of the line.

Next, the operation will be described. In FIG. 1, a triplate line composed of a triplate line ground conductor 1, a triplate line inner conductor 3, and a dielectric substrate 5 passes through a conversion unit 6, passes through a microstrip line ground conductor 2, a microstrip line upper conductor 4, and It is converted into a microstrip line composed of the dielectric substrate 5. The characteristic impedance of the triplate line is determined by the distance between the two triplate line ground conductors 1 and the triplate line inner conductor 3, the line width of the triplate line inner conductor 3, and the dielectric constant of the dielectric substrate 5. The characteristic impedance of the microstrip line is determined by the distance between the microstrip line ground conductor 2 and the microstrip line upper conductor 4, the line width of the microstrip line upper conductor 4, and the dielectric constant of the dielectric substrate 5. When converting the triplate line and the microstrip line, it is required to make the characteristic impedances equal to each other. However, the thickness and the material of the dielectric substrate 5 to be used are limited, and the conductor 3 in the triplate line and the microstrip line are used. When the upper conductor 4 is provided on the same plane, there may be no solution for the line width that satisfies the desired characteristic impedance. Further, even if a solution exists, for example, the line width may become extremely thin or wide, and the withstand power characteristics may not satisfy the required value or the loss may increase. In the present invention, since the dielectric substrate 5 is bent as shown in FIG. 1 by the conversion section 6 between the microstrip line and the triplate line, the distance between the triplate line ground conductor 1 and the triplate line inner conductor 3 can be arbitrarily set. The characteristic impedances of the triplate line and the microstrip line can be easily matched. Further, there are restrictions on the dielectric constant and thickness of the dielectric substrate 5, and in the structure of FIG. 1, when the width of the microstrip line upper conductor 4 is too narrow, a dielectric spacer is further added to the dielectric substrate 5. It is also possible to pinch. In the present invention, since the inner conductor 3 of the triplate line and the upper conductor 4 of the microstrip line are integrally formed on one substrate, for example, in the case of etching, after the etching is performed once, the conversion unit 6 is processed. The strip line can be obtained by a simple processing step such as forming the substrate by press working with a curvature, which is very economical. Note that a dielectric spacer may be inserted between the dielectric substrate 5 and the triplate line ground conductor 1 to reinforce the strip line, or the triplate line ground conductor 1 may be fixed by conductor pins or through holes.

Embodiment 2 FIG. FIG. 2 is a configuration diagram of the strip line according to the second embodiment of the present invention. In FIG. 2, reference numeral 7 denotes a triplate line ground conductor short-circuited portion, and reference numerals 1 to 6 denote the same as those in FIG.

Next, the operation will be described. In this embodiment, the effect of bending the substrate of the conversion part 6 of the triplate line and the microstrip line is the same as that of the first embodiment, but the conversion part 6 is provided with the triplate line ground conductor short-circuit part 7. Generally, when a triplate line and a microstrip line are joined, the two triplate line ground conductors 1 of the triplate line and the microstrip line ground conductor 2 of the microstrip line are short-circuited by the conversion unit 6, and the potential between the ground conductors is reduced. Are equal, the reflection is reduced. In this embodiment, a triplate line ground conductor short-circuit portion 7 is provided to obtain the effect. In the example of FIG. 2, a part of the dielectric substrate on which the ground conductor is mounted is cut out as the triplate line ground conductor short-circuiting portion 7, and it is folded back as shown in FIG. Conducted. Thus, the reflection loss at the conversion unit 6 can be reduced. Further, if a structure in which a part of the dielectric substrate including the ground conductor is cut off and folded back as in this embodiment, there is no need to newly provide an extra short-circuit conductor part, and the cost is reduced. Also, the triplate line ground conductor short-circuit portion 7
In this case, there is only an area where the continuity processing is required only at a joint part of the triplate line to the other ground conductor, and there is an advantage that the processing process is simplified. However, when a material that is difficult to be bent is used as the dielectric substrate 5 on which the ground conductor is mounted,
A pin, a through hole, a conductor plate, or the like may be used as the short-circuit conductor.

Embodiment 3 FIG. FIG. 3 is a configuration diagram of the strip line according to the third embodiment of the present invention. In FIG. 3, reference numeral 8 denotes a conductor 3 in a triplate line.
The joining conductors 1 and 3 to 7 of the microstrip line upper conductor 4 are the same as those in FIG.

Next, the operation will be described. The embodiment of FIG. 3 differs from the embodiment of FIG. 2 in that the triplate line inner conductor 3 and the strip line upper conductor 4 and the strip line upper conductor 4 and the triplate It has a structure in which it is joined by a trapezoidal joint conductor 8 formed on the same plane as the line conductor 3. The advantages of providing such a joint conductor 8 are as follows. Even if the triplate line and the microstrip line are designed to have the same characteristic impedance, the characteristic impedances of the converters 6 are generally not equal due to the discontinuity of connecting lines having different shapes. Further, in the present invention, the height of the conductor 3 in the triplate line and the upper conductor 4 of the microstrip line from the ground plane are not equal. The substrate must be bent to the height of the line upper conductor 4, and the characteristic impedance deviates from the design value. If the joint conductor 8 is provided, such a displacement of the impedance can be corrected, and the triplate line and the microstrip line can be connected well. It has been experimentally confirmed that the shape of the joint conductor 8 is preferably a trapezoid or a rectangle as shown in FIG.

Embodiment 4 FIG. FIG. 4 is a configuration diagram of the strip line according to the fourth embodiment of the present invention. In FIG. 4, 9 is a film substrate, 10 is a dielectric spacer, and 1-4 and 7 are the same as those in FIG.

Next, the operation will be described. In the embodiment of FIG. 4, the electrical characteristics are the same as those described in the first, second, and third embodiments. However, a foldable film substrate 9 is used as the dielectric substrate. Further, a dielectric spacer 10 is provided as a support member for the triplate line. The advantages of using the film substrate 9 are as follows. First, the film substrate 9 is very light and the cost is low. Furthermore, since it is freely bendable, the bending of the substrate in the conversion unit 6 can be easily performed. In FIG. 4, a dielectric spacer 10 is provided to fix the bending. The use of the film substrate 9 has the following advantages. When it is desired to crawl the strip line along the surface of the housing, it is difficult to process with a hard substrate. However, if the bendable film substrate 9 is used, the problem is eliminated, and the strip line can be mounted on the case surface having a complicated shape. In the present embodiment, the film substrate 9 is used as the dielectric substrate in the first and second embodiments.
This is a difference from the second and third embodiments, and all the advantages of the first, second, and third embodiments can be applied to the present embodiment as they are.

[0020]

As described above, according to the present invention, in the strip line according to the first aspect, the tri-plate and the tri-plate can be formed by simple processing while maintaining the degree of freedom in selecting the characteristic impedance of each line. A strip line in which the line and the microstrip line are mixed can be obtained.
In the strip line according to claim 2 or 3 , the reflection loss at the converter between the strip line and the triplate line can be reduced. In the strip line according to the fourth aspect , impedance matching between the strip line and the triplate line can be easily obtained. According to the strip line of the fifth aspect , in addition to the above-described effects, a strip line that is lightweight, low-cost, easy to process, and has good attachment to the housing can be obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a strip line according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a strip line according to a second embodiment of the present invention.

FIG. 3 is a configuration diagram of a strip line according to a third embodiment of the present invention.

FIG. 4 is a configuration diagram of a strip line according to a fourth embodiment of the present invention.

FIG. 5 is a configuration diagram of a conventional strip line.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Triplate line ground conductor 2 Microstrip line ground conductor 3 Triplate line inner conductor 4 Microstrip line upper conductor 5 Dielectric substrate 6 Conversion part 7 Triplate line ground conductor short-circuit part 8 Joining conductor 9 Film substrate 10 Dielectric spacer

Claims (5)

(57) [Claims] 1. A strip line configured by connecting a microstrip line and a triplate line,
One of the two ground conductors of the triplate line and the ground conductor of the microstrip line are shared as a conductor surface provided on the surface of the first dielectric substrate, and the ground conductor of the microstrip line is A conductive strip conductor used as the upper conductor and the inner conductor of the triplate line is formed on the same surface of the second dielectric substrate,
The height of the upper conductor of the microstrip line from the conductor surface provided on the surface of the first dielectric substrate, and the height of the inner conductor of the triplate line provided on the surface of the first dielectric substrate. In the converter of the upper conductor of the microstrip line and the inner conductor of the triplate line, on the second dielectric substrate, A strip line obtained by bending a second dielectric substrate. 2. The upper part of the microstrip line
Between the conductor and the conversion part of the inner conductor of the triplate line.
And the two ground conductors of the triplate line,
2. A short circuit connected by a conductor.
The described stripline. 3. The upper part of the microstrip line.
Between the conductor and the conversion part of the inner conductor of the triplate line.
A part of the first dielectric substrate having the conductor surface
A notch is provided, and the above-mentioned notch is folded back.
One of the two ground conductors of the triplate line
Check that the conductor surface, which is a conductor, has been short-circuited to the other ground conductor.
The strip line according to claim 1, wherein: 4. An upper conductor of the microstrip line.
And the inner conductor of the triplate line, the second dielectric
Formed on the same plane as the upper and inner conductors of the board
It is characterized by being joined by a trapezoidal or rectangular conductor
The strip line according to claim 1. 5. The first dielectric substrate and the second dielectric substrate.
Place one or both of the body substrates on a foldable dielectric
5. A substrate according to claim 1, wherein said substrate is a lum substrate.
2. The strip line according to claim 1.