JPH06310917A - Microstrip line device - Google Patents

Abstract

PURPOSE:To prevent the increase in the reflection and loss of a high frequency signal by decreasing a ground connection impedance between the microstrip line board and a drop-in shaped component. CONSTITUTION:A drop-in shaped component 2 having a high frequency signal transmission lead 3 mounted on a base plate 1 and a microstrip line board 4 made of a dielectric substance installed on the base plate 1 and having a transmission line 4a inputting or outputting the high frequency signal to/from the high frequency signal transmission lead 3 are provided. Then a finger plate 5 made of a resilient metal whose tip finger part 5a is in press contact with a ground face of the drop-in shaped component 2 is interposed between the microstrip line board 4 and the base plate 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microstrip line device for supplying a high frequency signal from a transmission line of a microstrip line substrate to a drop-in shaped part on a base plate.

[0002]

2. Description of the Related Art FIG. 11 is a cross-sectional view showing a general conventional microstrip line device, in which 1 is a base plate for mounting high frequency circuit components, and 2 is a drop-in shape mounted on the base plate 1. Parts, 3
Is a lead for high frequency signal transmission of the drop-in shaped component 2,
4 is a microstrip line substrate.

Further, a is a ground plane of the drop-in shaped component 2, b is a ground plane of the microstrip line substrate 4, and
c is the return current of the high frequency signal flowing between the ground planes a and b. The microstrip line substrate 4 is a dielectric, and a transmission line 4a of a conductor serving as a microstrip line is provided on the surface thereof, and the base plate 1 is made of a metal having a low electric resistance such as aluminum.

Next, the operation will be described. In the microstrip line device having such a configuration, the high-frequency signal passes through the transmission line 4a on the surface of the microstrip line substrate 4,
Power is supplied to the leads 3 of the drop-in shaped component 2. At this time, the return current c of the high-frequency signal flows from the ground plane a of the drop-in shaped component 2 to the ground plane b of the microstrip line substrate 4 which faces the drop current in the route shown in the figure.

[0005]

Since the conventional microstrip line device is constructed as described above, the ground plane a of the drop-in shaped component 2 and the ground plane b of the microstrip line substrate 4 are separated from each other. Therefore, the ground connection impedance becomes high, and there are problems such as signal reflection and increase in loss particularly in microwaves having a high frequency. A technology similar to the conventional microstrip line device is published by Ohmsha Co., Ltd., March 30, 1988, Electronic Information and Communication Handbook,
P26 and Japanese Utility Model Laid-Open No. 59-154915, Japanese Utility Model Laid-Open No. 60-25208, and Japanese Utility Model Laid-Open No. 4-107904.

The invention of claim 1 has been made to solve the above-mentioned problems. By lowering the ground connection impedance between the microstrip line substrate and the drop-in shaped component, signal reflection and An object is to obtain a microstrip line device that can prevent an increase in loss.

It is an object of the present invention to provide a microstrip line device which can be attached to a base plate without damage when the microstrip line substrate is made of ceramic or the like.

According to the third aspect of the present invention, the conductive rubber is used without using the finger plate, so that the distance between the ground planes of the drop-in component and the microstrip line substrate can be easily reduced, and the characteristic impedance of the connection point can be reduced. It is an object of the present invention to obtain a microstrip line device capable of suppressing the turbulence of the device.

It is an object of the invention of claim 4 to obtain a microstrip line device capable of connecting a microstrip line substrate and a drop-in component without disturbing the characteristic impedance.

According to a fifth aspect of the present invention, there is provided a microstrip line device capable of positioning a drop-in shaped component so that the connection between the microstrip line substrate and the drop-in shaped component can be performed without disturbing the characteristic impedance. To aim.

[0011]

According to a first aspect of the present invention, there is provided a microstrip line device having a drop-in component having a high-frequency signal transmission lead mounted on a base plate, and being installed on the base plate. A dielectric microstrip line substrate having a transmission line for inputting or outputting a high frequency signal to a high frequency signal transmission lead, and between the microstrip line substrate and the base plate, made of a spring metal, and having a tip end. The finger portion interposes a finger plate that comes into contact with the ground contact surface of the drop-in shaped component.

According to the second aspect of the present invention, there is provided a microstrip line device made of a spring metal soldered to the lower surface of the microstrip line substrate, and a finger portion at the tip of the microstrip line substrate is in contact with the ground surface of the drop-in shaped component. The finger plate is provided, and the mounting metal plate installed on the base plate is soldered to the lower surface of the finger plate.

In the microstrip line device according to a third aspect of the present invention, a mounting metal plate having one end protruding outward from the microstrip line substrate is provided between the microstrip line substrate and the base plate, and the mounting metal plate. Is provided with a conductive rubber in contact with the ground surface of the drop-in shaped component.

In the microstrip line device according to the invention of claim 4, the finger portion of the finger plate is constituted by the inductance of the high frequency signal transmission lead and the capacitance between the finger portion and the high frequency signal transmission lead. The shape is such that the characteristic impedance and the characteristic impedance of the microstrip line match.

In the microstrip line device according to a fifth aspect of the present invention, a recess formed in the base plate for dropping and installing the drop-in shaped component is provided with a recess between the finger portion of the finger plate and the high frequency signal transmission lead. So that the characteristic impedance including the capacitance matches the characteristic impedance of the microstrip line,
The shape is such that the drop-in shaped component is positioned.

[0016]

In the microstrip line device according to the present invention, the finger portion of the finger plate inserted between the microstrip line substrate and the base plate is brought into contact with the drop-in shaped component, so that the drop-in shaped component and the micro It is possible to reduce the ground connection impedance with the strip line substrate.

In the microstrip line device according to the second aspect of the present invention, the finger plate and the microstrip line substrate are sequentially soldered on the mounting metal so that the material of the microstrip line substrate is a fragile member such as ceramic. Even if there is, it is not necessary to fix it with a screw, for example, and it is possible to avoid the occurrence of cracks.

In the microstrip line device according to the third aspect of the present invention, the conductive rubber attached to the mounting metal plate is brought into contact with the drop-in shaped component to ground the drop-in shaped component and the microstrip line substrate. Enables reduction of connection impedance.

A microstrip line device according to a fourth aspect of the present invention comprises an inductance component of a high frequency signal transmission lead, and a capacitance component between a finger portion of a finger plate and a high frequency signal transmission lead of a drop-in shaped component. To match the characteristic impedance of the microstrip line with the characteristic impedance
The shape of the finger portion is determined.

In the microstrip line device according to a fifth aspect of the present invention, the drop-in shaped component is dropped into the recess formed in the base plate and positioned, whereby
The corresponding positions of the finger parts of the finger plate and the high-frequency signal transmission leads of the drop-in shaped parts can be positioned with a constant and high precision, and the microstrip line and the high-frequency signal transmission leads can be connected without disturbing the characteristic impedance. To do so.

[0021]

EXAMPLES Example 1. Hereinafter, an embodiment of the invention of claim 1 will be described with reference to the drawings. In FIG. 1, 1 is a base plate for mounting high frequency circuit components, 2 is a drop-in shaped component which is one of the high frequency circuit parts mounted on the base plate 1, and 3 is a lead for high frequency signal transmission of the drop-in shaped component 2. Reference numeral 4 is a microstrip line substrate.

Further, a is a ground plane of the drop-in shaped component 2, b is a ground plane of the microstrip line substrate 4, and
c is the return current of the high frequency signal flowing between the ground planes a and b.

Reference numeral 5 denotes a finger plate, which is made of metal such as beryllium copper or phosphor bronze, which has a spring property and a low electric resistance, and is a microstrip line as shown in FIG. The base plate 1 is placed on the lower surface of the substrate 4 together with the microstrip line substrate 4 by screws or the like.
It is fixed to. The drop-in component 2 is also fixed to the base plate 1 with a screw or the like, and the finger portion 5a of the tip of the finger plate 5 bent in a U shape is in contact with the ground surface a.

Next, the operation will be described. In this embodiment, the finger portion 5a of the finger plate 5 put under the microstrip line substrate 4 is brought into contact with the ground plane a of the drop-in shaped component 2, so that the ground plane a of the drop-in shaped component 2 is removed from the ground plane a. The ground plane b of the microstrip line substrate 4 is connected by a short circuit via the finger portions 5a. The finger portions 5a are provided with slits at sufficiently short intervals with respect to the wavelength λ.

As a result, the ground connection impedance of the ground circuit can be lowered, and even when a microwave signal having a high frequency is handled, it is possible to suppress signal reflection and increase in loss. Since the finger portions 5a are provided with the slits, the finger portions 5a are reliably connected to the ground planes a at a plurality of points, and the ground connection impedance is stabilized.

Example 2. In the embodiment, the finger plate 5 is laid under the microstrip line substrate 4, but as shown in FIG. 3, the microstrip line substrate 4 and the finger plate 5 are separately prepared for mounting metal. The plate 6 and the plate 6 may be integrated by soldering. By doing so, for example, when the material of the microstrip line substrate 4 is ceramic, cracking occurs at the time of mounting, as compared with the case of screw fixing. Can be prevented.

Example 3. Further, although the finger plate 5 is used in the above-mentioned embodiment, as shown in FIG. 4, the finger plate 5 is eliminated and the microstrip line substrate 4 is directly mounted on the mounting metal plate 7, and further, as shown in FIG.
As shown in, the conductive rubber 8 is fitted to one end of the mounting metal plate 7 having a smaller electric resistance than the microstrip line substrate 4 so as to come into contact with the ground plane a of the drop-in shaped component 2. However, the same effect as that of the above-described embodiment may be obtained.

Example 4. If the processing accuracy is not constant with respect to the shape, size, etc. of the finger portions 5a of the finger plate 5, the high frequency signal transmission leads 3
And the characteristic impedance formed by the electrostatic capacitance between the finger portion 5a and the high frequency signal transmission lead do not match the characteristic impedance of the microstrip line of the microstrip line substrate, and the wavelength of the high frequency signal in this non-coincidence section. If the ratio to λ becomes too large to be ignored, the characteristic impedance will be disturbed and will not be constant. Therefore, the finger portion is formed in a shape such that the characteristic impedances described above match. For example, the arcuate shape and size of the finger portion are set with high accuracy in advance.

Example 5. 6 and 7 are a cross-sectional view and a partial exploded perspective view showing a microstrip line device having such a finger plate 5. Instead of the arcuate finger portion 5a shown in FIGS. A plurality of finger portions 5b that stand upright and are horizontal at the top are provided. It should be noted that slits 5c are provided so that these finger portions 5b have a sufficient spring property, and the drop-in shaped component 2 and the microstrip substrate 4 face each other with a gap D therebetween.

In this way, the processing accuracy of each finger portion 5b can be increased, and the characteristic impedance formed by the inductance of the high frequency signal transmission lead 3 and the capacitance between the finger portion 5b and the high frequency transmission lead 3 can be improved. Can be matched with the characteristic impedance of the microstrip line, and the disturbance of the characteristic impedance can be prevented even when the ratio of the high frequency signal to the wavelength is large.

Example 6. 8 and 9 show a case where the gap D shown in FIG. 6 is small and the bending margin of the finger portion 5b cannot be sufficiently secured. In this case, the finger portions 5d alternately provided with respect to the slits 5c are simply erected obliquely, and the tips are brought into contact with the ground contact surface a of the drop-in shaped component 2.

According to this, the return circuit is further shortened, and the inductance of the high frequency signal transmission lead 3 is
Since the characteristic impedance composed of the finger portion 5d and the capacitance between the high frequency transmission lead 3 does not largely deviate from the characteristic impedance of the microstrip line, the characteristic impedance of the entire connection portion can be optimized. Further, in this case, since the contact portion is an edge of the finger portion 5d, even if the ground plane a of the drop-in shaped component 2 is made of a metal such as aluminum whose surface is covered with an oxide film, it is fine. A good connection is achieved by biting into the ground plane a.

Example 7. In addition, in the mounting structure of the drop-in shaped component 2 shown in FIG. 1, the arcuate shape of the finger portions 5a of the finger plate 5 is difficult to obtain dimensional accuracy due to springback, and in some cases shorts to the high-frequency signal transmission lead 3. Because there is a risk of
The drop-in shaped component 2 is configured so that the contact amount of the finger portion 5a with respect to the ground contact surface a of the drop-in shaped component 2 becomes a predetermined value with a constant width that does not cause the short circuit.
Position.

Therefore, as shown in FIG. 10, the side surface 11a of the recess 11 for dropping the drop-in shaped component 2 formed in the base plate 1 opposite to the side where the finger plate 5 is provided is shown in FIG. The drop-in shaped part 2 is used as a positioning part. In this case, the shape 11a of the recess may be a step shape in which the drop-in shaped component 2 can be easily dropped, or a shape in which a padding for performing the positioning adjustment can be easily installed.

[0035]

As described above, according to the invention of claim 1, the drop-in shaped component having the high frequency signal transmission lead mounted on the base plate and the high frequency signal transmission installed on the base plate. And a microstrip line substrate of a dielectric having a transmission line for inputting or outputting a high frequency signal to a lead for use, between the microstrip line substrate and the base plate, made of a spring metal, and a finger portion at the tip. Since the finger plate abutting against the ground plane of the drop-in shaped component is interposed, the ground connection impedance between the microstrip line and the drop-in shaped component can be lowered with an extremely simple structure. There is an effect that can be obtained.

According to the second aspect of the present invention, a finger made of a spring-like metal soldered to the lower surface of the microstrip line substrate, and the finger portion at the tip is in contact with the ground surface of the drop-in shaped component. Since the plate is provided and the mounting metal plate to be installed on the base plate is soldered to the lower surface of the finger plate, it is possible to mount the microstrip line substrate made of ceramic or the like on the base plate without damage. There is an effect to be obtained.

According to the third aspect of the present invention, a mounting metal plate having one end protruding outward from the microstrip line substrate is provided between the microstrip line substrate and the base plate, and the one end of the mounting metal plate is provided. Since the conductive rubber that comes into contact with the ground surface of the drop-in shaped component is provided, the ground connection impedance between the microstrip line and the drop-in shaped component can be reduced by simply mounting the conductive rubber. There is an effect that can be obtained.

According to the fourth aspect of the invention, the finger portion of the finger plate has a characteristic impedance composed of the inductance of the high-frequency signal transmission lead and the capacitance between the finger portion and the high-frequency signal transmission lead, and a microscopic impedance. Since the shape is matched with the characteristic impedance of the strip line, there is an effect that the microstrip line and the drop-in shaped component can be connected without disturbing the characteristic impedance.

According to the fifth aspect of the present invention, the recess formed in the base plate for mounting the drop-in shaped component by dropping it includes the capacitance between the finger portion of the finger plate and the high frequency signal transmission lead. Since the drop-in shaped component is positioned so that the characteristic impedance and the characteristic impedance of the microstrip line match, the microstrip line substrate and the drop-in shaped component are connected using a simple positioning structure. There is an effect that what can be done without disturbing the characteristic impedance is obtained.

[Brief description of drawings]

FIG. 1 is a sectional view showing a microstrip line device according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view showing an arrangement relationship between a microstrip line substrate and finger plates in FIG.

FIG. 3 is a perspective view showing a microstrip line device according to an embodiment of the present invention.

FIG. 4 is a sectional view showing a microstrip line device according to an embodiment of the present invention.

FIG. 5 is an exploded perspective view showing a mounting relationship of the conductive rubber in FIG. 4 to a mounting metal plate.

FIG. 6 is a sectional view showing a microstrip line device according to an embodiment of the invention of claim 4;

7 is an exploded perspective view showing an arrangement relationship between a microstrip line substrate and finger plates in FIG.

FIG. 8 is a sectional view showing a microstrip line device according to another embodiment of the invention of claim 4;

9 is an exploded perspective view showing an arrangement relationship between a microstrip line substrate and finger plates in FIG.

FIG. 10 is a sectional view showing a microstrip line device according to an embodiment of the present invention.

FIG. 11 is a cross-sectional view showing a conventional microstrip line device.

[Explanation of symbols]

 1 base plate 2 drop-in shaped component 3 high frequency signal transmission lead 4 microstrip line substrate 4a transmission line 5 finger plate 5a, 5b, 5d finger part 6, 7 mounting metal plate 8 conductive rubber 11 recess

Claims (5)

[Claims] 1. A drop-in component having a high-frequency signal transmission lead mounted on a base plate, and a transmission line installed on the base plate for inputting or outputting a high-frequency signal to the high-frequency signal transmission lead. In the microstrip line device including a dielectric microstrip line substrate, between the microstrip line substrate and the base plate, a finger-like portion made of a spring metal and having a tip finger portion is a ground plane of the drop-in shaped component. A microstrip line device characterized in that a finger plate abutting on the substrate is interposed. 2. A drop-in component having a high-frequency signal transmission lead mounted on a base plate, and a transmission line installed on the base plate for inputting or outputting a high-frequency signal to the high-frequency signal transmission lead. In a microstrip line device having a dielectric microstrip line substrate, the microstrip line substrate is made of a spring-like metal soldered to the lower surface of the microstrip line substrate, and the finger portion at the tip is the ground plane of the drop-in shaped component. A microstrip line device comprising: a finger plate that is in contact with the base plate; and a mounting metal plate that is soldered to the lower surface of the finger plate and that is installed on the base plate. 3. A drop-in component having a high-frequency signal transmission lead mounted on a base plate, and a transmission line installed on the base plate for inputting or outputting a high-frequency signal to the high-frequency signal transmission lead. In a microstrip line device comprising a dielectric microstrip line substrate, provided between the microstrip line substrate and the base plate,
A mounting metal plate whose one end projects outward from the microstrip line substrate, and a conductive rubber which is mounted on the one end of the mounting metal plate and contacts the ground plane of the drop-in shaped component are provided. A microstrip line device characterized by the above. 4. The finger portion of the finger plate,
The characteristic impedance formed by the inductance of the high frequency signal transmission lead and the capacitance between the finger portion and the high frequency signal transmission lead and the characteristic impedance of the microstrip line are matched with each other. Item 2. The microstrip line device according to Item 2. 5. A microstrip and a characteristic impedance constituted by a capacitance formed between a finger portion of a finger plate and a high frequency signal transmission lead, in which a recess formed in a base plate for dropping and installing a drop-in shaped component is installed. The microstrip line device according to claim 1 or 2, wherein the drop-in shaped component is positioned so as to match the characteristic impedance of the line.