JPH11234001A - Millimeter wave transmission line - Google Patents

Abstract

PROBLEM TO BE SOLVED: To transmit millimeter waves with high efficiency and a minimized loss by forming a dielectric waveguide, so as to continuously deform it into an expanding shape part that is partly opened in the distribution direction of an electric field from a cylindrical shape part. SOLUTION: A dielectric waveguide is formed so as to be continuously deformed into an expanding shape part, that is partly opened in the distribution direction of an electric field from a cylindrical shape part. For instance, the waveguide includes a planar shape part 20 which forms a rectangular waveguide, a cylindrical shape part 21 which forms a circular waveguide and a converting part 22 where the part 20 is changed into the part 21. The part 22 continuously deforms the sectional shape of the dielectric waveguide into a cyclindrical shape from a planar shape. Thus, the waveguide receives the electromagnetic waves propagating in a space via the part 20 in a rectangualr TE10 mode, that is approximate to the mode of the waves and then transmits these waves after converting them into a circular TE01 mode of the part 21 via the part 22. Thus, a millimeter wave transmission line can be miniaturized and the mechanical performance of the waveguide can be stabilized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a millimeter wave transmission line using a dielectric waveguide.

[0002]

2. Description of the Related Art Since a millimeter wave has a short wavelength and propagates linearly, a great application is expected in the future as a high-resolution radar or a radio wave for large-capacity short-range communication.

As a millimeter wave transmission line, a microstrip line, a waveguide, a coaxial tube, and the like have been conventionally used. Although these lines are widely used as transmission lines in the microwave band, they are hardly used in practical use except for the antenna portion because they have a large loss in millimeter waves and require high processing accuracy.

[0004] Instead of these lines, recently NRD
(Non Radiative Dielectric
c) A line, that is, a non-radiative dielectric line has been proposed and started to be practically used as a millimeter wave transmission line.

FIG. 1 shows an example of the structure of the NRD line. In FIG. 1, reference numerals 10 and 11 denote metal shield plates, and 12 denotes a dielectric (Teflon) inserted between these two metal shield plates 10 and 11. Waveguide made of fluororesin such as resin)
Reference numeral 13 denotes an electric flux. This NRD line is
It has the advantage that the loss is small and high processing accuracy is not required compared to the metal waveguide.

[0006]

In such an NRD line, the electric field is strong at the center of the line. Therefore, when attaching an element that exchanges energy by voltage, such as a semiconductor element, it is necessary to extract energy from the center of the waveguide 12 where the electric field is maximum. Therefore, when an element is mounted on the NRD line or when a connection terminal for connecting to an external circuit is provided on the NRD line, it is necessary to arrange the element or terminal so that it floats in a space at the center of the line. However, according to such a structure, a structure for holding the element and the terminal is required, and there is a problem that the electromagnetic influence greatly affects the operation of the line, for example, changing the operation mode.

[0007] In a practically used NRD line,
As described above, a fluororesin having a small dielectric loss is used. However, since this fluororesin has a low adhesive activity, a sufficient mechanical force is required for bonding the waveguide 12 to the metal shielding plates 10 and 11 sandwiching the waveguide. Insufficient mechanical strength, thermal expansion coefficient is several times larger than metal, so it is not only difficult to couple with other waveguides, but also sufficient mechanical stability against environmental tests cannot be obtained There were also problems such as.

Further, in the NRD line, since other transmission modes exist close to the basic transmission mode, the range of the optimum dimensions of the line must be narrowed in order to prevent an increase in loss due to the occurrence of the other transmission modes. There is also a problem that it cannot be obtained.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a millimeter wave transmission line which can efficiently transmit a millimeter wave with a loss as small as possible and has a simple structure.

Another object of the present invention is to provide a millimeter-wave transmission line which can be easily connected to an external circuit or a circuit element and has a small transmission loss.

[0011]

According to the present invention, there is provided a cylindrical shape portion and an expanded shape portion in which at least a part of the distribution direction of the electric field is open, and the continuous shape from the cylindrical shape portion to the expanded shape portion is provided. There is provided a millimeter-wave transmission line including a dielectric waveguide that is deformed in nature and a metal housing having the dielectric waveguide therein.

[0012] The dielectric waveguide has a developed shape portion in which at least a part of the cylindrical shape portion in the electric field distribution direction is open;
For example, it is configured to be continuously deformed into a semi-open waveguide having an opening or a planar shape part forming a rectangular waveguide. For this reason, the transmission loss at the transition from the cylindrical portion to the developed shape portion is very small, and the configuration of that portion is also simplified. In addition, connection with an external circuit or a circuit element can be easily performed.

It is preferable that the cylindrical portion is a circular waveguide that can propagate the circular _T01 mode with the least transmission loss.

It is preferable that the semi-open waveguide having an opening is a U-shaped waveguide having a substantially U-shaped axial cross section. It is preferable that a metal layer forming a connection terminal is formed in the opening of the U-shaped waveguide, and it is more preferable that a metal layer for impedance matching be formed. Thus, a terminal structure that facilitates connection with an external circuit or an active element can be easily realized.

The metal casing in the planar shape portion constituting the rectangular waveguide is preferably rectangular T ₁₀ mode is a rectangular waveguide which can propagate. In this case, the planar shape portion is composed of a flat plate having a width equal to the height of the inner surface of the rectangular waveguide, and the flat plate is disposed at the center of the rectangular waveguide and parallel to the side surface thereof. Is preferred. Accordingly, after receiving the electromagnetic waves propagating through space in a rectangular TE ₁₀ mode close to that mode, it is possible to transmit by converting most transmission loss is small circular TE ₀₁ mode, the miniaturization of the millimeter wave transmission line, the machine Stabilization of dynamic performance can be achieved.

More preferably, the flat plate terminates in the rectangular waveguide with a tapered tip having a length equal to or longer than a 1/4 guide wavelength. In this way, by making the vertical cross-sectional area of the tip of the flat plate gradually and continuously change over a length equal to or more than a quarter of the guide wavelength, the electromagnetic wave is transferred from the rectangular waveguide to the dielectric waveguide. When light is incident, no reflection occurs.

It is preferable that an opening hole is provided in the cylindrical portion, and a metal layer forming a connection terminal is formed in the opening hole, and a metal layer for impedance matching is further provided in the opening hole. More preferably, it is formed. Thereby, a terminal structure having the same function as the above-described semi-open waveguide can be realized more easily.

The metal housing in the cylindrical portion has a circular shape T _01.
A mode-suppressed circular waveguide that suppresses modes other than the mode is preferable. As its structure, for example, a circular waveguide having a slit extending in the circumferential direction,
It may be a circular waveguide with an insulated wire wound in a coil. As described above, if the dielectric line is installed in a metal case (mode-suppressed circular waveguide) having a large loss with respect to modes other than the circular TE ₀₁ mode, the line can be formed without being hindered by higher-order unnecessary modes. It can be operated stably.

It is also preferred that the dielectric waveguide is made of fired ceramic or quartz glass.

[0020]

FIG. 2 is a perspective view schematically showing a configuration of a part of a dielectric waveguide in an embodiment of a millimeter wave transmission line according to the present invention.

In FIG. 1, reference numeral 20 denotes a planar portion forming a rectangular waveguide, 21 denotes a cylindrical portion forming a circular waveguide, and 22 denotes a conversion portion from the planar portion 20 to a cylindrical portion 21. The conversion unit 22 is configured to continuously deform the cross-sectional shape from a plane to a cylinder. Planar shape part 2
After receiving the electromagnetic waves propagating through space in a rectangular TE ₁₀ mode close to this mode at 0, the conversion unit 22, and transmits the converted most circular TE ₀₁ mode transmission loss is small cylindrical portion 21, a millimeter wave transmission The line is downsized and the mechanical performance is stabilized.

This dielectric waveguide is formed of ceramic or quartz glass. For example, after mixing a ceramic raw material with a binder and a solvent to form a tape, the solvent evaporates to dry the tape. Prior to this, it is put into a mold and shaped as shown in FIG. It is formed by drying the shaped body and firing it by a usual ceramic technique to obtain a sintered body.

FIG. 3 is a perspective view showing a see-through example of the configuration of a transmission line obtained by housing a part of the dielectric waveguide shown in FIG. 2 in a metal housing.

In the figure, reference numeral 30 denotes a rectangular waveguide for accommodating the planar shape portion 20 of the dielectric waveguide, and 31 denotes a circular waveguide for accommodating the cylindrical shape portion 21. Rectangular waveguide 30 if there is no dielectric waveguide is a waveguide which operates in a rectangular TE ₁₀ mode circular waveguide 31 is a waveguide which operates in a circular TE ₀₁ mode. The planar shape portion 20 has a width equal to the height of the inner surface of the rectangular waveguide 30 (corresponding to the height in the figure).
Is installed in the center parallel to the side.

Further, the planar shape portion 20 has a tapered tip 20a having a length equal to or longer than a 1/4 guide wavelength, and terminates in the rectangular waveguide 30 at the tip 20a. As described above, since the vertical cross-sectional area of the distal end 20a of the planar shape portion 20 is configured to change gradually and continuously over a length equal to or longer than the 1/4 guide wavelength, the rectangular waveguide 30 is formed.
When an electromagnetic wave enters the dielectric waveguide from above, no reflection occurs.

The dielectric waveguide is supported and fixed in the metal housing by annular supports 32 arranged at appropriate intervals around the cylindrical portion 21. The support 32 is desirably formed of a material having a small dielectric constant, such as styrene foam.

FIG. 4 is a perspective view showing another example of a transmission line obtained by housing a part of the dielectric waveguide shown in FIG. 2 in a metal housing.

In the same figure, reference numeral 40 denotes a rectangular waveguide accommodating the planar shape portion 20 of the dielectric waveguide, and 41 denotes a circular waveguide accommodating the cylindrical shape portion 21. In this case the rectangular waveguide 40 also is the absence of the dielectric waveguide is a waveguide which operates in a rectangular TE ₁₀ mode, the circular waveguide 41 is a waveguide which operates in a circular TE ₀₁ mode By providing a plurality of partial slits 41a provided in the circumferential direction in a partially connected state, it is configured to have an unnecessary mode suppressing function.

That is, the metal casing (circular waveguide 41) surrounding the dielectric waveguide is provided with the circular TE induced by the dielectric waveguide.
_In some cases, a mode other than the ₀₁ mode occurs, and transmission by the dielectric waveguide cannot be performed. In order to avoid such troubles, it is necessary to suppress the occurrence of modes other than the circular TE ₀₁ mode. In the circular TE ₀₁ mode, only the displacement current in the circumferential direction exists as shown in FIG. 2, and the current induced in the metal casing is only the current in the circumferential direction. In other modes, a current in the propagation axis direction is also generated on the metal casing, so if the metal casing has a structure that suppresses the current in the propagation axis direction, modes other than the circular TE ₀₁ mode are suppressed and transmission loss Transmission line with less noise.

Therefore, in the configuration example of FIG.
By the provision of the plurality of partial slits 41a in the circumferential direction, with each other to suppress the modes other than the circular TE ₀₁ mode by blocking current propagation axis.

When the transmission frequency is 60 GHz, the inner diameter of the circular TE ₀₁ mode circular waveguide having this frequency as a cutoff frequency is 6.1 mm. Actually, a dielectric constant of 7.5 and a thickness of 150 obtained by manufacturing a glass-alumina dielectric green sheet by a normal ceramic manufacturing method in a metal pipe having an inner diameter of 5 mm with a slit in the circumferential direction.
When a cylindrical dielectric having a diameter of 2 μm and an outer diameter of 2 mm is mounted, a dielectric waveguide transmitting a frequency of 60 GHz at a guide wavelength of 2.4 mm can be formed.

FIG. 5 is a perspective view of a transmission line obtained by housing a part of the dielectric waveguide shown in FIG. 2 in a metal housing.

In the figure, reference numeral 50 denotes a rectangular waveguide accommodating the portion of the planar shape portion 20 of the dielectric waveguide, and 51 denotes a circular waveguide accommodating the portion of the cylindrical shape portion 21, respectively. In this case the rectangular waveguide 50 also is the absence of the dielectric waveguide is a waveguide which operates in a rectangular TE ₁₀ mode, the circular waveguide 51 is a waveguide which operates in a circular TE ₀₁ mode Is configured to have an unnecessary mode suppression function.

In this configuration example, a circular waveguide 51 having an unnecessary mode suppressing function is realized by winding an insulated wire in a coil shape, and a current in the propagation axis direction is blocked to suppress modes other than the circular TE ₀₁ mode. doing.

In the configuration examples shown in FIGS. 3 to 5, the cross section of the metal housing in the cylindrical portion is the same circular shape as the dielectric waveguide for miniaturization. If the housing becomes a cut-off waveguide at the frequency transmitted by the dielectric waveguide when operated as, it may have another cross-sectional shape.

FIG. 6 is a perspective view schematically showing the configuration of another part of the dielectric waveguide in the above embodiment.

In FIG. 6A, reference numeral 60 denotes a semi-open waveguide having an opening 60a formed by cutting a part of a circular waveguide, reference numeral 61 denotes a cylindrical portion forming a circular waveguide, and reference numeral 6 denotes a circular waveguide.
Reference numeral 2 denotes a conversion unit from the cylindrical portion 61 to the semi-open waveguide 60. The conversion section 62 continuously deforms the cross-sectional shape from a cylinder to a substantially U-shaped shape shown in FIG. 4B, so that the circular waveguide 61 and the semi-open waveguide 60 are electrically connected smoothly. Is configured. The opening 60a is
It is provided to connect circuit elements such as C and a diode to this portion and to connect to an external circuit. The cylindrical portion 61 is a waveguide through which an electromagnetic wave propagates in the circular TE ₀₁ mode. However, the electromagnetic wave also propagates through the semi-open waveguide 60 as shown in FIG. Accordingly, the signal transmitted in the circular TE ₀₁ mode in the cylindrical portion 61 is guided to the semi-open waveguide 60 with a minimum loss and inputted to the circuit element mounted thereon. The semi-open waveguide 60, the cylindrical portion 61, and the conversion portion 62 are the same as those in FIG.
Alternatively, as shown in FIG. 5, it is accommodated in a circular waveguide 41 or 51 which operates in a circular TE ₀₁ mode and has an unnecessary mode suppressing function.

This dielectric waveguide is also formed of ceramic or quartz glass. For example, after mixing a ceramic raw material with a binder and a solvent to form a tape, the solvent evaporates to dry the tape. Before performing the process, it is placed in a mold and a part of the cylindrical portion is cut open as shown in FIG. The shaped body is formed by drying and firing by a usual ceramic technique to obtain a sintered body.

FIG. 7 is a perspective view showing a state in which connection terminals are provided on the semi-open waveguide shown in FIG. 6A and other circuit elements are mounted.

As shown in the figure, a connection terminal 73 is formed by printing a metal on the edge of the opening 70a of the semi-open waveguide 70, and a circuit element 74 such as an IC or a diode is mounted on the connection terminal. . In a conventional waveguide or NRD line, other elements cannot be directly connected to the line. However, by adopting a structure as shown in FIG. 7, it is easy to configure a microwave / millimeter wave circuit including active elements. become. Although not shown, a metal may be baked before and after the attached element 74 to form an impedance matching circuit.

FIG. 8 is a perspective view showing another structural example for attaching another circuit element to the cylindrical portion of the dielectric waveguide.

As shown in the figure, an opening hole 81a is provided in the middle of the cylindrical portion 81, a metal is burned on the edge thereof to form a connection terminal 83, and a circuit element 84 such as an IC or a diode is connected to the connection terminal 83. Mount on terminals. This makes it easy to configure a microwave / millimeter wave circuit including active elements, as in the case of FIG. It is desirable to form the impedance matching circuit 85 by baking a metal before and after the attached element 84.

FIGS. 9A and 9B are a perspective view and a sectional view, respectively, showing a structure in which an element is attached to the planar shape portion of the dielectric waveguide shown in FIG.

In FIGS. 9A and 9B, reference numeral 90 denotes a stepped planar portion of the dielectric waveguide, 91 denotes a rectangular waveguide accommodating the portion of the planar portion 90 of the dielectric waveguide, and 92 denotes a rectangular waveguide. A gun diode 93 connected to the lower end of the step portion of the planar shape portion 90 and an impedance matching circuit 93 formed by baking a metal on the surface of the planar shape portion 90 are shown. Rectangular waveguide 91 if there is no dielectric waveguide is a waveguide which operates in a rectangular TE ₁₀ mode. For example, an active circuit such as a waveguide Gunn diode oscillator needs to dissipate heat by attaching one surface to a metal part. Therefore, this Gunn diode 9 is placed on the inner bottom surface of the rectangular waveguide 91.
By attaching 2 to a connection terminal formed by baking a metal on the lower surface of the end of the planar shape portion 90, connection of an active circuit such as a waveguide type Gunn diode oscillator can be easily performed.

FIG. 10 is a perspective view showing an example of the configuration of a circuit element formed on the cylindrical portion of the dielectric waveguide.

In the figure, reference numeral 100 denotes a cylindrical portion of the dielectric waveguide, and 101 denotes a half-wavelength (λ
/ 2) coupling gaps (slits provided in the circumferential direction) provided at intervals of 102, which are inserted so as to penetrate through the cylindrical portion 100, and support each cylindrical portion separated by the slit. Each shows a dielectric.
By cutting the cylindrical portion 100 at a length of a half wavelength, an open-ended resonator can be obtained. The dielectric 102
, A resonant circuit formed in the transmission line can be obtained.

FIG. 11 is a perspective view showing another configuration example of the circuit element formed on the cylindrical portion of the dielectric waveguide.

In the figure, reference numeral 110 denotes a cylindrical portion of the dielectric waveguide, and 111 denotes a half-wavelength (λ
/ 2) a plurality of coupling gaps (slits provided in the circumferential direction), 112, which are inserted so as to penetrate through the cylindrical portion 110, and support each cylindrical portion separated by the slit. Reference numeral 113 denotes a plurality of resonators. As described above, a band-pass filter can be formed by coupling a plurality of resonators 113 shown in FIG.

FIG. 12 is a perspective view showing still another configuration example of the circuit element formed in the cylindrical portion of the dielectric waveguide.

In the figure, reference numeral 120 denotes a cylindrical portion of the dielectric waveguide, and 121 denotes a half-wavelength (λ
/ 2), a plurality of gaps (partial slits provided in the circumferential direction) in which a part is connected, and 123 indicate a plurality of resonators, respectively. The inside of the cylindrical portion 120 is hollow. As described above, by forming a cut-off waveguide in which a part of the waveguide is cut off and the part is cut off at the operating frequency, resonance occurs in the waveguide cut and separated by the slit as shown in FIGS. A resonator and a bandpass filter can be formed without forming a resonator.

FIG. 13 is a perspective view schematically showing a configuration of a dielectric waveguide according to still another embodiment of the millimeter wave transmission line of the present invention.

In the same figure, reference numeral 130 denotes a first planar shape part forming a rectangular waveguide, 131 denotes a first cylindrical part forming a circular waveguide, and 132 denotes a first planar shape part from the first planar shape part 130. A first conversion section into the cylindrical section 131, 133 is a semi-open waveguide having a shape obtained by cutting a part of a circular waveguide, and 134 is a second conversion section from the first cylindrical section 131 to the semi-open waveguide 133. , 135 is a second planar portion forming a rectangular waveguide, 136 is a second cylindrical portion constituting a circular waveguide, and 137 is a second cylindrical portion from the second planar portion 135 to a second cylindrical portion. The third conversion part 136 into the semi-open waveguide 133 from the second cylindrical part 136
Is a conversion unit. First and third conversion units 132 and 13
7 is configured to continuously deform the cross-sectional shape from a plane to a cylinder. The second and third converters 134 and 138 continuously deform the cross-sectional shape from a cylinder to a substantially U-shape to form the first and second circular waveguides 131.
136 and the semi-open waveguide 133 are electrically connected to each other smoothly.

First and second planar shape portions 130 and 13
After receiving the electromagnetic waves propagating through space in a rectangular TE ₁₀ mode close to this mode at 5, the conversion unit 1 of the first and third
32 and 137, the first and second cylindrical portions 131 and 136 having the least transmission loss are respectively converted into circular TE ₀₁ mode and transmitted, and the millimeter wave transmission line is reduced in size.
It is designed to stabilize mechanical performance. Also, the first
And a circular T at the second cylindrical portions 131 and 136.
The signal transmitted in the _E01 mode is converted into a semi-open waveguide 133.
And input to the circuit element mounted thereon with the minimum loss.

This dielectric waveguide is also formed of ceramic or quartz glass. For example, after mixing a ceramic raw material with a binder and a solvent to form a tape, the solvent evaporates to dry the tape. Prior to the process, it is put into a mold and a part of the cylindrical portion is cut open to form as shown in FIG. It is formed by drying the shaped body and firing it by a usual ceramic technique to obtain a sintered body.

FIG. 14 is a perspective view showing an example of a millimeter-wave converter constructed in a metal housing by combining the various structures and circuit elements described above.

In the figure, 140 is a horn antenna,
141 is a rectangular waveguide formed of a plate-shaped portion, 142 is a conversion portion, 143 is a rectangular waveguide-type metal housing that houses the rectangular waveguide 141 and the conversion portion 142 therein, and 144 is a circular waveguide formed of a cylindrical portion. , 145 is a band-pass filter, 14
6 is a converter, 147 is a semi-open waveguide having a substantially U-shaped cross section, 148 is a semiconductor IC mounted on the semi-open waveguide 147, 149 is a coaxial line for extracting an intermediate frequency output from the semiconductor IC, and 150 is a converter. , 151 is a circular waveguide having a cylindrical shape, 152 is a band-pass filter, 153 is circular waveguides 144 and 151, semi-open waveguide 147, converters 146 and 150, and band-pass filters 145 and 15
2 and a semiconductor IC 148 are accommodated inside, and a circular waveguide type metal housing with an unnecessary mode suppression function, 154 is a conversion unit,
Reference numeral 55 denotes a rectangular waveguide formed of a plate-shaped portion, 156 denotes a Gunn diode connected to the rectangular waveguide 155, 157 denotes an impedance matching circuit provided in the rectangular waveguide 155, 1
Reference numeral 58 denotes a rectangular waveguide-type metal housing that houses the Gunn diode 156, the rectangular waveguide 155, and the converter 154, respectively.

The signal incident from the left horn antenna 140 is mode-converted into a circular waveguide 144, passed through a band-pass filter 145, and applied to a converter IC 148. On the other hand, the local oscillation signal generated by the gun diode oscillator 156 on the right side is also supplied to the converter IC 148 through the band-pass filter 152. IC148
A signal dropped to an intermediate frequency is produced from both signals mixed in the coaxial line 149 which also serves as a support for the waveguide.
Is taken out to the outside.

The embodiments described above are merely examples of the present invention, and do not limit the present invention. The present invention can be embodied in various other modified forms and modified forms. Therefore, the scope of the present invention is defined only by the appended claims and their equivalents.

[0059]

As described above in detail, according to the present invention, the dielectric waveguide has a developed shape portion, for example, an opening, which is at least partially opened from the cylindrical shape portion in the electric field distribution direction. It is configured to be continuously deformed into a planar shape portion forming a semi-open waveguide or a rectangular waveguide.
For this reason, the transmission loss at the transition from the cylindrical portion to the developed shape portion is very small, and the configuration of that portion is also simplified. In addition, connection with an external circuit or a circuit element can be easily performed.

By processing a ceramic sheet or a quartz glass sheet before firing to form a dielectric waveguide having a flat cross section and a dielectric circular waveguide and a change portion where both are electrically connected smoothly, loss can be reduced. Resonators and bandpass filters can be easily formed on the waveguide. If a semi-open waveguide is formed by cutting a part of the circular waveguide, a transmission line on which an active element or the like can be easily attached can be formed by printing a terminal on the open surface. Such a waveguide forming method is,
It utilizes the plastic deformation characteristic of ceramic or quartz glass, and it is relatively difficult to form a waveguide by such a method using other materials. Since the actual current does not flow through this waveguide and only the displacement current is present, no resistance loss due to the skin effect occurs, and a low-loss line can be easily formed.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a structural example of an NRD line.

FIG. 2 is a perspective view schematically showing a configuration of a part of a dielectric waveguide in the embodiment of the millimeter wave transmission line of the present invention.

FIG. 3 is a perspective view showing in perspective a configuration example of a transmission line obtained by housing a part of the dielectric waveguide shown in FIG. 2 in a metal housing.

FIG. 4 is a perspective view showing another example of the configuration of a transmission line obtained by housing a part of the dielectric waveguide shown in FIG. 2 in a metal housing.

FIG. 5 is a perspective view of a transmission line obtained by housing a part of the dielectric waveguide shown in FIG. 2 in a metal housing and showing still another configuration example;

FIG. 6 is a perspective view schematically showing a configuration of another part of the dielectric waveguide in the embodiment of FIG. 2;

FIG. 7 is a perspective view showing a state in which connection terminals are provided on the semi-open waveguide shown in FIG. 6A and other circuit elements are mounted.

FIG. 8 is a perspective view showing another structural example for attaching another circuit element to the cylindrical portion of the dielectric waveguide.

9A and 9B are a perspective view and a cross-sectional view showing a structure in which an element is attached to a planar shape portion of the dielectric waveguide shown in FIG.

FIG. 10 is a perspective view showing one configuration example of a circuit element formed in a cylindrical portion of a dielectric waveguide.

FIG. 11 is a perspective view showing another configuration example of the circuit element formed on the cylindrical portion of the dielectric waveguide.

FIG. 12 is a perspective view showing still another configuration example of the circuit element formed in the cylindrical portion of the dielectric waveguide.

FIG. 13 is a perspective view schematically showing a configuration of a dielectric waveguide in still another embodiment of the millimeter wave transmission line of the present invention.

FIG. 14 is a perspective view showing an example of a millimeter-wave converter configured in a metal housing by combining the above-described structure and circuit elements.

[Explanation of symbols]

20, 130, 135, 141, 155 Planar shape portion 20a Tip 21, 61, 81, 100, 110, 120, 131,
136, 144, 151 Cylindrical portion 22, 62, 132, 134, 137, 138, 14
2, 146, 150, 154 Converter 30, 40, 50, 91, 143 Rectangular waveguide 31, 41, 51 Circular waveguide 32 Support 41a Partial slit 60, 70, 133, 147 Semi-open waveguide 60a 70a Openings 73,83 Connection Terminals 74,84 Circuit Element 81a Openings 85,93,157 Impedance Matching Circuit 90 Stepped Planar Parts 92,156 Gunn Diode 101,111 Coupling Gap 102,112 Dielectric 113,123 Resonator 121 Partial slit 140 Horn antenna 145, 152 Bandpass filter 148 Semiconductor IC 149 Coaxial line 153 Circular waveguide type metal housing 158 Rectangular waveguide type metal housing

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Ryoichi Kondo 1-13-1 Nihonbashi, Chuo-ku, Tokyo Inside TDK Corporation

Claims (16)

[Claims] 1. A dielectric body having a cylindrical portion and a developed portion having at least a part of the electric field distributed in an open direction, and continuously deforming from the cylindrical portion to the developed shape portion. A millimeter-wave transmission line comprising: a waveguide; and a metal housing having the dielectric waveguide therein. 2. The method according to claim 1, wherein the cylindrical portion of the dielectric waveguide comprises:
2. The millimeter wave transmission line according to claim 1, wherein the transmission line is a circular waveguide capable of transmitting a circular _T01 mode. 3. The developed shape portion of the dielectric waveguide,
3. The millimeter wave transmission line according to claim 1, wherein the transmission line is a semi-open waveguide having an opening. 4. The millimeter wave transmission line according to claim 3, wherein the semi-open waveguide is a U-shaped waveguide having a substantially U-shaped axial cross section. 5. The millimeter wave transmission line according to claim 4, wherein a metal layer forming a connection terminal is formed in the opening of the U-shaped waveguide. 6. The millimeter wave transmission line according to claim 5, wherein a metal layer for impedance matching is further formed in the opening of the U-shaped waveguide. 7. The development shape portion of the dielectric waveguide,
3. The millimeter wave transmission line according to claim 1, wherein the millimeter wave transmission line is a planar shape portion forming a rectangular waveguide. Wherein said metal housing in the planar shape portion, the millimeter wave transmission line according to claim 7, characterized in that the rectangular T ₁₀ mode is a rectangular waveguide which can propagate. 9. The planar shape portion is formed of a flat plate having a width equal to a height of an inner surface of the rectangular waveguide,
The millimeter wave transmission line according to claim 8, wherein the flat plate is disposed at the center of the rectangular waveguide in parallel with a side surface thereof. 10. The millimeter wave transmission line according to claim 9, wherein the flat plate terminates in the rectangular waveguide with a tapered tip having a length equal to or longer than a 1/4 guide wavelength. . 11. An opening according to claim 7, wherein an opening is provided in said cylindrical portion, and a metal layer forming a connection terminal is formed in said opening. 2. The millimeter wave transmission line according to 1. 12. The millimeter wave transmission line according to claim 11, wherein a metal layer for impedance matching is further formed in the opening. The metal housing of claim 13, wherein the cylindrical portion, to any one of claims 1, characterized in that the inhibit mode suppression circular waveguide modes other than the circular T ₀₁ mode 12 Millimeter wave transmission line as described. 14. The millimeter wave transmission line according to claim 13, wherein the mode suppressing circular waveguide is a circular waveguide having a slit extending in a circumferential direction. 15. The millimeter wave transmission line according to claim 13, wherein the mode-suppressing circular waveguide is a circular waveguide in which an insulated wire is wound in a coil shape. 16. The millimeter wave transmission line according to claim 1, wherein said dielectric waveguide is formed of fired ceramic or quartz glass.