JPH09321507A - Mode converter - Google Patents

Abstract

(57) Abstract: To reduce the radio wave loss between a microstrip line and a triplate-type stripline. A pair of ground conductors 41 are sandwiched between transmission line conductors 11 on a dielectric substrate 12 of the microstrip line 10 in the vicinity of a connecting surface 30 between the microstrip line 10 and a triplate type strip line 20. , 41
Spread out. Further, the conductor 34 connects the ground conductor 41 and the ground conductor 31. Mode converter 100 having such a configuration
According to the method, the mode can be gently converted, so that the joint surface 30
The reflection of radio waves in the vicinity can be prevented, and the radio waves can be reliably propagated. Therefore, the radio wave loss is reduced. In addition, since the mode converter with less radio wave loss can be configured in a plane, the arrangement on the plane of the substrate or the like becomes easy, and the configuration / arrangement of the electric circuit becomes simple.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mode converter, and more particularly to a mode converter for converting radio waves from a microstrip mode to a triplate type strip mode.

[0002]

2. Description of the Related Art FIG. 14 is a perspective view showing a conventional mode converter. FIG. 15 is a sectional view taken along line AA ′ of FIG. In the figure, 10 is a microstrip line. The microstrip line 10 has a structure in which a strip-shaped transmission line conductor 11 is spread on the upper surface of a dielectric substrate 12 and a ground conductor 31 is spread on the lower surface thereof. Transmission line conductor 1
1 and the ground conductor 31 face each other in parallel.

Reference numeral 20 is a triplate type strip line. This triplate type strip line 20 is
In this structure, a strip-shaped transmission line conductor 21 is embedded in the center of the dielectric substrate 13, and ground conductors 32 and 33 are spread on the upper and lower surfaces thereof. The transmission line conductor 21 opposes the conductors 32 and 33 in parallel.

A joining surface 30 is formed by joining the microstrip line 10 and the triplate type strip line 20. At the joint surface 30, the transmission line conductor 11 and the transmission line conductor 21 are connected to each other by the transmission line connecting conductor 5.
1 connected. Here, the mode converter 600 refers to the periphery of the bonding surface 30.

Next, the mode conversion operation of the mode converter 600 will be described. In the microstrip line 10, as shown in FIG.
The electric field is distributed between 1 and the ground conductor 31. The radio wave propagating through the microstrip line 10 is transmitted through the transmission line connecting conductor 51 to the triplate type strip line 2
Lead to zero.

The transmission mode of the radio wave guided to the triplate type strip line 20 is drastically converted from the microstrip mode (quasi-TEF mode) to the triplate type strip mode (TEF mode), as shown in FIG. 16 (b). , The ground conductors 32, 3 around the transmission line conductor 21
The electric field is distributed between 3 and 3.

[0007]

However, since the above-described conventional mode converter 600 is configured as described above, the transmission mode in the transmission line connecting conductor 51 is changed from the microstrip mode to the triplate type strip mode. It will be rapidly converted to, and the reflection of radio waves will occur in such a part. Therefore, there is a problem that the radio wave cannot be reliably propagated.

The present invention has been made in view of the above, and an object of the present invention is to obtain a mode converter capable of reducing the radio wave loss between the microstrip line and the triplate type strip line. .

[0009]

In order to achieve the above-mentioned object, a mode converter of the present invention comprises a microstrip line which supports a ground conductor facing one surface of a transmission line conductor, and a transmission line conductor. A mode converter for converting radio waves between a microstrip mode and a triplate type strip mode at a connection portion with a triplate type strip line that supports two ground conductors facing each other on both sides of In the vicinity of the connection portion, a mode conversion mitigating means is provided which further adds a ground conductor to change the line cross section of the microstrip line to bring the electric field distribution in the microstrip line closer to the electric field distribution in the triplate type strip line. It is a thing.

That is, any mode converter constituted by connecting a microstrip line and a triplate type strip line can be arranged on a plane, so that the electric circuit can be easily arranged and arranged. Highly used for mobile phones, etc. Furthermore, EMI resistance
When high performance is required, it is necessary to properly use the microstrip line and the triplate type strip line.

On the other hand, since there is no margin in the high frequency output power due to the limitation of the battery, it is desired to reduce the radio wave loss during mode conversion as much as possible. However, if the microstrip line and the triplate-type strip line are simply connected, the mode conversion at the connection portion becomes abrupt and the radio wave is reflected to cause a loss.

Therefore, the mode loss is reduced by gently performing the mode conversion. That is, since the electric field distribution is generated between the transmission line conductor and the ground conductor, by adding the ground conductor to an appropriate portion of the microstrip line, the line cross section of the microstrip line is changed to change the electric field distribution. I changed it gradually. Therefore, mode conversion is performed gently, the reflection of radio waves is prevented, and it is possible to reliably propagate the waves.

A mode converter according to the next invention supports a microstrip line formed by supporting a ground conductor facing one surface of a transmission line conductor and two ground conductors facing both surfaces of the transmission line conductor. In a mode converter for converting a radio wave between a microstrip mode and a triplate type strip mode at a connection portion with a triplate type strip line, the triplate is further provided in the vicinity of the connection portion. The mode conversion mitigating means is provided for changing the cross section of the die strip line to bring the electric field distribution in the microstrip line closer to the electric field distribution in the triplate type strip line.

That is, in the above-mentioned case, the line cross section of the microstrip line is changed by adding the ground conductor to an appropriate part of the microstrip line. The ground conductor was added to the to change the cross section of the line. Also in this configuration, similarly to the above, mode conversion is performed gently, and radio waves can be reliably propagated.

A mode converter according to the next invention supports a microstrip line formed by supporting a ground conductor facing one surface of a transmission line conductor and two ground conductors facing both sides of the transmission line conductor. In a mode converter for converting a radio wave between a microstrip mode and a triplate type strip mode at a connection portion with a triplate type strip line, the microstrip is further provided with a ground conductor near the connection portion. A mode conversion relaxation means is provided for changing the line cross section of the line and the triplate type strip line to bring the electric field distribution in the microstrip line closer to the electric field distribution in the triplate type strip line.

That is, by adding the ground conductor, the line cross sections of both the microstrip line and the triplate type strip line are changed. In such a configuration, mode conversion is performed more gently than in the above configuration, and radio waves are reliably propagated.

A mode converter according to the next invention comprises a transmission line conductor of a microstrip line formed by supporting one surface of a transmission line conductor and a ground conductor, and two transmission line conductors facing each other. A transmission line conductor connecting portion that connects the transmission line conductor of the triplate type strip line supporting the ground conductor, a ground conductor of the microstrip line, and one ground conductor of the triplate type strip line. In a mode converter for converting radio waves between a microstrip mode and a triplate-type strip mode, a ground conductor connection part for connecting the microstrip line is provided on both left and right sides of the conduction line conductor of the microstrip line. A ground conductor is further provided substantially parallel to the ground conductor of the strip line and in the vicinity of the transmission line conductor connection portion. It is.

That is, the line cross section of the microstrip line is changed in order to moderately convert the mode. As a concrete structure, it is substantially parallel to the ground conductor on both sides of the conduction line conductor of the microstrip line. To
Moreover, a ground conductor is further provided in the vicinity of the transmission line conductor connecting portion. As a result, mode conversion is performed gently, and radio waves are reliably propagated. Furthermore, since the mode converter can be easily and planarly configured, it becomes easy to dispose the mode converter on a plane, and the configuration / arrangement of the electric circuit also becomes simple.

A mode converter according to the next invention comprises a transmission line conductor of a microstrip line formed by supporting a ground conductor facing one surface of a transmission line conductor and two transmission line conductors facing each other. A transmission line conductor connecting portion that connects the transmission line conductor of the triplate type strip line supporting the ground conductor, a ground conductor of the microstrip line, and one ground conductor of the triplate type strip line. In a mode converter for converting radio waves between a microstrip mode and a triplate type strip mode, a ground conductor connecting portion for connecting the The ground conductor is further provided substantially parallel to the ground conductor of the triplate-type strip line and in the vicinity of the transmission line conductor connection portion. In which the provided.

In this case, the ground conductor is provided not on the microstrip line side but on the triplate type strip line side. That is, ground conductors were further provided on both the left and right sides of the conduction line conductor of the triplate type strip line substantially parallel to the ground conductor and near the transmission line conductor connection portion.

In this way, similarly to the above, mode conversion is performed gently, and radio waves are reliably propagated. Also,
Since the mode converter can be easily and planarly configured, it becomes easy to arrange the mode converter on a plane, and the configuration of the electric circuit
Placement is also easy.

In the mode converter according to the next invention, the transmission line conductor of the microstrip line, which is opposed to one surface of the transmission line conductor and supports the ground conductor, and two of the transmission line conductor are opposed to each other. A transmission line conductor connecting portion that connects the transmission line conductor of the triplate type strip line supporting the ground conductor, a ground conductor of the microstrip line, and one ground conductor of the triplate type strip line. In a mode converter for converting radio waves between a microstrip mode and a triplate type strip mode, a ground conductor connecting portion for connecting the Flat on both left and right sides to the ground conductor of the microstrip line and the triplate type strip line. Becomes, and, in the vicinity of the transmission line conductor connection portion, in which further provided with a ground conductor.

In this case, ground conductors are provided on the microstrip line side and the triplate type strip line side. That is, ground conductors are further provided substantially parallel to the ground conductor on both left and right sides of the transmission line conductors of the microstrip line and the triplate type strip line, and near the transmission line conductor connection portion.

By doing so, similarly to the above, mode conversion is performed more gently, and the radio wave is reliably propagated.
Further, since the mode converter can be easily and planarly configured, it becomes easy to dispose the mode converter on a plane, and the configuration / arrangement of the electric circuit is also simplified.

A mode converter according to the next invention supports a microstrip line formed by supporting a ground conductor facing one surface of a transmission line conductor and two ground conductors facing both sides of the transmission line conductor. In the mode converter for converting the electric wave between the microstrip mode and the triplate type strip mode in the connection part with the triplate type strip line, the connection point between the microstrip line and the triplate type strip line is An external electromagnetic wave shielding conductor for connecting the ground conductors of the triplate-type strip line and shielding an electromagnetic wave from the outside is provided.

That is, an external electromagnetic wave shield conductor for connecting the ground conductors of the triplate type strip line is provided in the connection portion so as to shield the electromagnetic wave from the outside. Therefore, it is less likely to be affected by the external environment. Also,
In the past, circuits such as transmission and reception systems and their transmission lines were placed apart to prevent interference, but such a configuration makes it less likely to be affected by the external environment, so circuits and transmission lines should be close to each other. Can be placed in Therefore, the device becomes compact.

A mode converter according to the next invention comprises a transmission line conductor of a microstrip line formed by supporting a ground conductor facing one surface of a transmission line conductor, and two transmission line conductors facing each other. A transmission line conductor connecting portion that connects the transmission line conductor of the triplate type strip line supporting the ground conductor, a ground conductor of the microstrip line, and one ground conductor of the triplate type strip line. , And a ground conductor connecting portion that connects the microstrip line and the tristrip type strip mode on the left and right sides of the conduction line conductor. The triple line is provided substantially perpendicular to the ground conductor of the plate-type strip line and near the transmission line conductor connection part. A connection between the ground conductor of preparative stripline is provided with a external radio wave blocking conductor to block radio waves from the outside.

Similarly to the above, an external electromagnetic wave shielding conductor for connecting between ground conductors of a triplate type strip line is provided in the transmission line conductor connecting portion so as to shield the electromagnetic wave from the outside. Therefore, it is less likely to be affected by the external environment.
Further, the circuit and the transmission line can be arranged in the vicinity because they are not easily affected by the external environment. Therefore, the device becomes compact.

In the mode converter according to the next invention, in the above mode converter, the ground conductors of the triplate-type strip line are connected to the connecting portion between the microstrip line and the triplate-type strip line from the outside. An external radio wave blocking conductor for blocking radio waves is provided.

In such a structure, similarly to the above, the influence of the external environment is suppressed, and the mode conversion is performed gently. Therefore, the device is not affected by the external environment and the device becomes compact. Further, the reflection of radio waves is prevented, and the radio waves can be reliably propagated.

In the mode converter according to the next invention, in the above mode converter, the transmission line conductors are provided on both side surfaces thereof perpendicularly to the ground conductors of the microstrip line and the triplate type strip line, and the transmission is performed. In the vicinity of the line conductor connecting portion, an external electromagnetic wave shield conductor is provided for connecting the ground conductors of the triplate-type strip line to shield the electromagnetic wave from the outside.

Similar to the above, the influence of the external environment is reduced, and the mode conversion is performed gently. Therefore, the device is not affected by the external environment and the device becomes compact. Further, the reflection of radio waves is prevented, and the radio waves can be reliably propagated.

[0033]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. The present invention is not limited to this embodiment.

(Embodiment 1) FIG. 1 is a perspective view showing a mode converter 100 of the present invention. FIG. 2 shows A of FIG.
It is a -A 'sectional view. In the figure, 10 is a microstrip line. This microstrip line 10
Is a structure in which the band-shaped transmission line conductor 11 is spread on the upper surface of the dielectric substrate 12 and the ground conductor 31 is spread on the lower surface thereof.
The transmission line conductor 11 and the ground conductor 31 face each other in parallel.

Further, a pair of ground conductors 41, 41 are spread on the dielectric substrate 12 with the transmission line conductor 11 interposed therebetween. Reference numeral 34 is a conductor that connects the ground conductor 41 and the ground conductor 31.

Reference numeral 20 is a triplate type strip line. This triplate type strip line 20 is
In this structure, a strip-shaped transmission line conductor 21 is embedded in the center of the dielectric substrate 13, and ground conductors 32 and 33 are spread on the upper and lower surfaces thereof. The transmission line conductor 21 opposes the conductors 32 and 33 in parallel.

The joining surface 3 is formed by joining the microstrip line 10 and the triplate type strip line 20.
0 is formed. At the joint surface 30, the transmission line conductor 11 and the transmission line conductor 21 are connected by the transmission line connecting conductor 51. Here, the mode converter 100 refers to the periphery of the joint surface 30.

Next, the mode conversion operation of the mode converter 100 will be described. In the microstrip line 10, as shown in FIG.
The electric field is distributed between the ground conductor 31 and the ground conductor 31.

Next, in the range where the ground conductor 41 is spread, it is converted into a transmission mode which is substantially intermediate between the microstrip mode and the triplate type strip mode, and as shown in FIG. An electric field is distributed between the ground conductor 31 and the ground conductors 41, 41 centering on the line conductor 11.

Subsequently, the radio wave propagating through the microstrip line 10 is guided to the triplate type strip line 20 through the transmission line connecting conductor 51. The transmission mode of the radio wave guided to the triplate type stripline 20 is completely converted from the microstrip mode to the triplate type strip mode, and as shown in FIG.
An electric field is distributed around the transmission line conductor 21 and between the ground conductors 32 and 33.

As described above, according to the mode converter 100,
Since the ground conductors 41, 41 are provided as described above, mode conversion from the microstrip mode to the triplate type strip mode can be performed gently. For this reason,
Radio waves are prevented from being reflected in the vicinity of the joint surface 30, and the radio waves can be reliably propagated, reducing radio wave loss. In addition, since the mode converter with less radio wave loss can be configured in a plane, the arrangement on the plane of the substrate or the like becomes easy, and the configuration / arrangement of the electric circuit becomes simple.

On the contrary, in the case of mode conversion from the triplate type strip mode to the microstrip mode, the same effect as above can be obtained.

(Second Embodiment) FIG. 4 is a perspective view showing a mode converter of the present invention. FIG. 5 shows AA ′ of FIG.
It is sectional drawing. This mode converter 200 includes a ground conductor 4
It is characterized in that 2, 42 are provided on the triplate-type stripline 20 side.

That is, a pair of ground conductors 42, 42 are embedded in the dielectric substrate 13 with the transmission line conductor 21 interposed therebetween. Reference numeral 35 is a conductor that connects the ground conductor 42 and the ground conductors 32 and 33. Other configurations are the same as those in the first embodiment.

Next, the mode conversion operation of the mode converter 200 will be described. In the microstrip line 10, as shown in FIG.
The electric field is distributed between the ground conductor 31 and the ground conductor 31.

Subsequently, the radio wave propagating through the microstrip line 10 is guided to the triplate type strip line 20 via the transmission line connecting conductor 51. Ground conductor 42,
In the range in which 42 is embedded, it is not completely converted to the triplate type strip mode, and as shown in FIG. 6B, between the ground conductor 31 and the ground conductors 41, 41 with the transmission line conductor 11 as the center. Electric field is distributed.

Next, when the range in which the ground conductors 42, 42 are buried is exceeded, the transmission mode of the radio wave is completely converted from the microstrip mode to the triplate type strip mode. In this case, as shown in FIG. 6C, an electric field is distributed between the ground conductors 32 and 33 centering on the transmission line conductor 21.

As described above, according to this mode converter 200,
Since the ground conductors 42, 42 are provided as described above, mode conversion from the microstrip mode to the triplate type strip mode can be performed gently. For this reason,
Radio waves are prevented from being reflected in the vicinity of the joint surface 30, and the radio waves can be reliably propagated, reducing radio wave loss. Further, since the mode converter with a small radio wave loss can be configured in a plane, the arrangement on the plane of the substrate becomes easy, and the configuration and arrangement of the electric circuit are simplified.

On the contrary, in the case of the mode conversion from the triplate type strip mode to the microstrip mode, the same effect as described above can be obtained.

(Third Embodiment) FIG. 7 is a perspective view showing a mode converter of the present invention. FIG. 8 shows AA ′ of FIG. 7.
It is sectional drawing. The mode converter 300 has a configuration in which the mode converter 100 and the mode converter 200 are combined.

That is, a pair of ground conductors 41, 41 are spread on the dielectric substrate 12 on the side of the microstrip line 10 with the transmission line conductor 11 interposed therebetween. 34 is a conductor that connects the ground conductor 41 and the ground conductor 31. Further, in the dielectric substrate 13 on the side of the triplate type strip line 20, a pair of ground conductors 42, 42 are embedded with the transmission line conductor 21 interposed therebetween. 35 is a ground conductor 42 and a ground conductor 32,
33 is a conductor for connecting with 33.

Next, the mode conversion operation of the mode converter 300 will be described. In the microstrip line 10, as shown in FIG.
The electric field is distributed between the ground conductor 31 and the ground conductor 31.

Next, in the range where the ground conductor 41 is spread, it is converted into a transmission mode which is substantially intermediate between the microstrip mode and the triplate type strip mode, and as shown in FIG. An electric field is distributed between the ground conductor 31 and the ground conductors 41, 41 centering on the line conductor 11.

Subsequently, the radio wave propagating through the microstrip line 10 is guided to the triplate type strip line 20 through the transmission line connecting conductor 51. And, in the range where the ground conductors 42, 42 are buried, it is not completely converted to the triplate type strip mode, and FIG.
As shown in FIG.
An electric field is distributed between 1 and the ground conductors 41, 41.

When the range in which the ground conductors 42, 42 are buried is exceeded, the transmission mode of the radio wave is completely converted from the microstrip mode to the triplate type strip mode, and as shown in (d) of FIG. An electric field is distributed between the line conductor 21 and the ground conductors 32 and 33.

As described above, according to this mode converter 300,
Mode conversion is performed more gently than the mode converter 100 and the mode converter 200. For this reason,
Radio waves are prevented from being reflected in the vicinity of the joint surface 30, and the radio waves can be reliably propagated, reducing radio wave loss. In addition, since the mode converter with less radio wave loss can be configured in a plane, the arrangement on the plane of the substrate or the like becomes easy, and the configuration / arrangement of the electric circuit becomes simple.

On the contrary, in the case of the mode conversion from the triplate type strip mode to the microstrip mode, the same effect as described above can be obtained.

(Fourth Embodiment) FIG. 10 is a perspective view showing a mode converter of the present invention. FIG. 11 shows A of FIG.
It is a -A 'sectional view. 12 is a sectional view taken along line BB ′ of FIG. The configuration of the mode converter 400 is substantially the same as that of the mode converter 200, except that conductors 43, 43 for preventing the entry of external radio waves are provided. FIG.
As shown in FIG. 2, the conductors 43, 43 are connected to the transmission line conductor 21.
The ground conductors 33 and 34 are connected to each other by being spread on the joint surface 30 with the pinch interposed therebetween.

Next, the mode conversion operation of the mode converter 400 will be described. In the microstrip line 10, as shown in FIG.
The electric field is distributed between 1 and the ground conductor 31.

Subsequently, the radio wave propagating through the microstrip line 10 is guided to the triplate type strip line 20 through the transmission line connecting conductor 51. At this time, electric waves from the outside are blocked by the conductors 43, 43 and do not enter the triplate-type stripline 20.

Next, in the range in which the ground conductors 42, 42 are embedded, the conversion is not completely performed up to the triplate type strip mode, and as shown in FIG. 13B, the ground conductor 31 is centered on the transmission line conductor 11. And ground conductors 41, 41
The electric field is distributed between and.

When the range in which the ground conductors 42, 42 are buried is exceeded, the transmission mode of the radio wave is completely converted from the microstrip mode to the triplate type strip mode, and as shown in FIG. An electric field is distributed around the conductor 21 and the ground conductors 32 and 33.

As described above, according to the mode converter 400,
Since the conductors 43, 43 are provided as described above, electric waves from the outside can be transmitted from the joint surface 30 to the triplate type strip line 20.
Never enter inside. Therefore, it is less likely to be affected by the external environment. Furthermore, since it is less likely to be affected by the external environment, the electric circuit and the mode converter 400 can be arranged in the vicinity. Therefore, the device becomes compact.

Further, mode conversion from the microstrip mode to the triplate type strip mode can be performed gently. Therefore, the reflection of the radio wave in the vicinity of the joint surface 30 is prevented, and the radio wave can be reliably propagated, and the radio wave loss is reduced. Further, since the mode converter with a small radio wave loss can be configured in a plane, the arrangement on the plane of the substrate becomes easy, and the configuration and arrangement of the electric circuit are simplified.

On the contrary, in the case of the mode conversion from the triplate type strip mode to the microstrip mode, the same effect as above can be obtained.

[0066]

As described above, according to the mode converter of the present invention, the ground conductor is added to an appropriate portion of the microstrip line to change the line cross section and gradually change the electric field distribution. did. Therefore, mode conversion is gently performed between the microstrip mode and the triplate-type strip mode, radio waves are prevented from being reflected, and radio wave loss is reduced. In addition, since it can be configured in a plane, it can be easily arranged on the plane of the substrate, etc., and the structure and arrangement of the electric circuit can be simplified.

In the mode converter according to the next invention, the ground conductor is added to an appropriate portion of the triplate type strip line to change the line cross section so that the electric field distribution is gradually changed. The conversion is slowed down, the reflection of radio waves is prevented, and the radio wave loss is reduced. Also,
Since it can be configured in a plane, it can be easily arranged on the plane of the substrate and the like, and the structure and arrangement of the electric circuit can be simplified.

A mode converter according to the next invention is a combination of the above-mentioned configurations. Ground conductors are provided on both the microstrip line and the triplate-type strip line to change the line cross section and gradually increase the electric field distribution. I changed it. Therefore, mode conversion is performed more gently than in the above configuration, and radio wave loss is reduced.

In the mode converter according to the next invention, as the above-mentioned concrete structure, on the left and right sides of the conduction line conductor of the microstrip line, substantially parallel to the ground conductor, and in the vicinity of the transmission line conductor connection portion, Further, a ground conductor is provided. Therefore, the cross section of the route changes, mode conversion is performed gently, and radio waves are reliably propagated. In particular, in such a configuration, since the mode converter can be made planar, it becomes easy to dispose on the plane of the substrate and the like, and the structure and disposition of the electric circuit can be simplified.

In the mode converter according to the next invention, the ground conductor is provided on the triplate type strip line side. That is, the ground conductor is further provided on both the left and right sides of the conduction line conductor of the triplate type strip line substantially parallel to the ground conductor and near the transmission line conductor connection portion.
For this reason, similarly to the above, the line cross section changes, mode conversion is gently performed, and radio waves are reliably propagated. Further, since the mode converter can be made planar, it becomes easy to arrange it on the plane of the substrate and the like, and the configuration and arrangement of the electric circuit can be made simple.

In the mode converter according to the next invention, ground conductors are provided on both the microstrip line and the triplate type strip line. Therefore, mode conversion is performed more gently than in the above configuration, and radio waves are reliably propagated.

In the mode converter according to the next invention, the external radio wave cutoff for cutting off the radio wave from the outside by connecting the ground conductors of the triplate type stripline to the connecting portion of the microstrip line and the triplate type stripline. A conductor is provided. Therefore, it is less likely to be affected by the external environment. Further, the circuit and the transmission line can be arranged in the vicinity because they are less likely to be affected by the external environment. Therefore, the device becomes compact.

In the mode converter according to the next invention, similarly to the above, an external electromagnetic wave shielding conductor for connecting the ground conductors of the triplate type strip line is provided at the connection portion of the transmission line conductors so as to shield the electromagnetic wave from the outside. did. Therefore, it is less likely to be affected by the external environment. Further, the circuit and the transmission line can be arranged in the vicinity because they are not easily affected by the external environment. Therefore, the device becomes compact.

In the mode converter according to the next invention, in the above mode converter, an external electromagnetic wave cutoff for connecting the ground conductors of the triplate type strip line to the connecting portion of the microstrip line and the triplate type strip line. A conductor is provided. For this reason, radio waves from the outside are blocked and are less likely to be affected by the external environment, and the circuit and the transmission line can be arranged in the vicinity. Therefore, the device becomes compact. Further, since the mode conversion is performed gently, the reflection of radio waves is prevented and the radio waves can be reliably propagated.

In the mode converter according to the next invention, as the above-mentioned specific configuration, the left and right sides of the conduction line conductor are perpendicular to the ground conductors of the microstrip line and the triplate type strip line, and An external electromagnetic wave shielding conductor that connects between the ground conductors of the triplate-type strip line is provided near the transmission line conductor connecting portion.
For this reason, radio waves from the outside are blocked and are less likely to be affected by the external environment, and the circuit and the transmission line can be arranged in the vicinity. Therefore, the device becomes compact. Further, since the mode conversion is performed gently, the reflection of radio waves is prevented and the radio waves can be reliably propagated.

[Brief description of drawings]

FIG. 1 is a perspective view showing a mode converter according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along the line A-A ′ shown in FIG.

FIG. 3 is an explanatory diagram showing a distribution of an electric field according to the first embodiment.

FIG. 4 is a perspective view showing a mode converter according to a second embodiment of the present invention.

5 is a cross-sectional view taken along the line A-A ′ shown in FIG.

FIG. 6 is an explanatory diagram showing electric field distribution according to the second embodiment.

FIG. 7 is a perspective view showing a mode converter according to a third embodiment of the present invention.

8 is a cross-sectional view taken along the line A-A ′ shown in FIG.

FIG. 9 is an explanatory diagram showing a distribution of an electric field according to the third embodiment.

FIG. 10 is a perspective view showing a mode converter according to a fourth embodiment of the present invention.

11 is a cross-sectional view taken along the line A-A ′ shown in FIG.

12 is a sectional view taken along line B-B ′ shown in FIG.

FIG. 13 is an explanatory diagram showing an electric field distribution according to the fourth embodiment.

FIG. 14 is a perspective view showing a conventional mode converter.

15 is a cross-sectional view taken along the line A-A ′ shown in FIG.

FIG. 16 is an explanatory diagram showing a conventional electric field distribution.

[Explanation of symbols]

100 mode converter, 10 microstrip line, 12 dielectric substrate, 11 transmission line conductor, 31 ground conductor, 12 dielectric substrate, 41 ground conductor, 34 conductor, 2
0 tri-plate type strip line, 13 dielectric substrate, 21 transmission line conductor, 32, 33 ground conductor, 30
Junction surface, 51 transmission line connecting conductor, 200 mode converter, 42 ground conductor, 35 conductor, 300 mode converter, 400 mode converter, 43, 44 conductor

Claims (10)

[Claims] 1. A microstrip line formed by supporting a ground conductor facing one surface of a transmission line conductor, and a triplate type strip line formed by supporting two ground conductors facing both surfaces of the transmission line conductor. In a mode converter for converting radio waves between a microstrip mode and a triplate-type strip mode at a connection portion with, a line conductor is further added near the connection portion to change the line cross section of the microstrip line. Accordingly, the mode converter is provided with a mode conversion relaxing means for bringing the electric field distribution in the microstrip line closer to the electric field distribution in the triplate-type strip line. 2. A microstrip line formed by supporting one side of a transmission line conductor and supporting a ground conductor, and a triplate type strip line formed by supporting two ground conductors on both sides of the transmission line conductor. In a mode converter for converting a radio wave between a microstrip mode and a triplate type strip mode at a connection portion with, a line cross section of the triplate type strip line is further added in the vicinity of the connection portion by adding a ground conductor. A mode converter comprising a mode conversion relaxing means for changing the electric field distribution in the microstrip line to the electric field distribution in the triplate strip line by changing the electric field distribution. 3. A microstrip line formed by supporting one side of a transmission line conductor and supporting a ground conductor, and a triplate type strip line formed by facing two sides of the transmission line conductor and supporting two ground conductors, respectively. In a mode converter for converting radio waves between a microstrip mode and a triplate type strip mode at a connection portion with the microstrip line and the triplate type strip line, a ground conductor is further added in the vicinity of the connection portion. 2. A mode converter, which is provided with a mode conversion relaxing means for making the electric field distribution in the microstrip line closer to the electric field distribution in the triplate-type strip line by changing the line cross section. 4. A transmission line conductor of a microstrip line, which is opposed to one surface of a transmission line conductor and supports a ground conductor, and two ground conductors, which are opposed to both surfaces of the transmission line conductor. The transmission line conductor of the triplate type strip line, and a transmission line conductor connecting portion for connecting,
A ground conductor connecting portion that connects the ground conductor of the microstrip line and one ground conductor of the triplate type strip line is provided, and radio waves are converted between a microstrip mode and a triplate type strip mode. In the mode converter, a ground conductor is further provided on the left and right sides of the conduction line conductor of the microstrip line, substantially parallel to the ground conductor of the microstrip line, and in the vicinity of the transmission line conductor connection portion. A mode converter characterized in that 5. A transmission line conductor of a microstrip line, which is opposed to one surface of a transmission line conductor and supports a ground conductor, and two ground conductors, which are opposed to both surfaces of the transmission line conductor, respectively. The transmission line conductor of the triplate type strip line, and a transmission line conductor connecting portion for connecting,
A ground conductor connecting portion that connects the ground conductor of the microstrip line and one ground conductor of the triplate type strip line is provided, and radio waves are converted between a microstrip mode and a triplate type strip mode. In the mode converter, the left and right sides of the conduction line conductor of the triplate type strip line are substantially parallel to the ground conductor of the triplate type strip line, and in the vicinity of the transmission line conductor connection portion. A mode converter characterized in that a conductor is provided. 6. The transmission line conductor of a microstrip line formed by supporting one side of a transmission line conductor and supporting the ground conductor, and two ground conductors facing each side of the transmission line conductor. The transmission line conductor of the triplate type strip line, and a transmission line conductor connecting portion for connecting,
A ground conductor connecting portion that connects the ground conductor of the microstrip line and one ground conductor of the triplate type strip line is provided, and radio waves are converted between a microstrip mode and a triplate type strip mode. In the mode converter, the transmission line conductor connection is made parallel to the ground conductors of the microstrip line and the triplate strip line on both left and right sides of the conduction line conductor of the microstrip line and the triplate strip line. A mode converter characterized in that a ground conductor is further provided near the portion. 7. A microstrip line formed by supporting one side of a transmission line conductor and supporting a ground conductor, and a triplate type strip line formed by facing two sides of a transmission line conductor and supporting two ground conductors, respectively. In a mode converter for converting a radio wave between a microstrip mode and a triplate type strip mode at a connection portion with, the triplate type strip line is provided at a connection portion between the microstrip line and the triplate type strip line. A mode converter characterized in that an external electromagnetic wave shielding conductor for connecting the ground conductors of (3) and shielding the electromagnetic wave from the outside is provided. 8. A transmission line conductor of a microstrip line that supports a ground conductor so as to face one surface of the transmission line conductor, and two ground conductors that face both sides of the transmission line conductor. The transmission line conductor of the triplate type strip line, and a transmission line conductor connecting portion for connecting,
A ground conductor connecting portion that connects the ground conductor of the microstrip line and one ground conductor of the triplate type strip line is provided, and radio waves are converted between a microstrip mode and a triplate type strip mode. In the mode converter, the triplate type is provided on the left and right sides of the conduction line conductor substantially perpendicular to the ground conductors of the microstrip line and the triplate type strip line, and in the vicinity of the transmission line conductor connection portion. A mode converter characterized in that an external radio wave blocking conductor is provided to connect ground conductors of a strip line and to block radio waves from the outside. 9. An external radio wave blocking conductor for blocking a radio wave from the outside by connecting between ground conductors of the triplate type strip line at a connecting portion between the microstrip line and the triplate type strip line. The mode converter according to any one of claims 1 to 3, which is characterized. 10. The triplate-type strip on both the left and right sides of the conduction line conductor, substantially perpendicular to the ground conductors of the microstrip line and the triplate-type strip line, and near the transmission line conductor connection portion. 7. The mode converter according to claim 4, further comprising an external radio wave blocking conductor that connects ground conductors of the line and blocks radio waves from the outside.