JPS5919441Y2 - Waveguide-microstrip line conversion circuit - Google Patents

Description

[Detailed description of the invention] This invention combines a rectangular waveguide and a microstrip line (unbalanced strip line) by terminating the end of the rectangular waveguide with a strip line, and connecting the waveguide to the strip line. The present invention relates to a waveguide-to-microstrip line conversion circuit having a configuration for directly converting lines.

In the past, conversion between stripline and waveguide was generally performed via a coaxial line.

In other words, first connect the strip line and the coaxial line,
Moreover, by coupling this coaxial line and a waveguide, conversion between a strip line and a waveguide was performed.

FIGS. 1a and 1l) show examples of conventional strip line/coaxial line conversion circuits and coaxial line/waveguide conversion circuits, respectively.

In FIG. 1a, 1 is a strip line, 2 is a coaxial line, 3 is a housing for supporting and fixing both, and 4 is a strip center conductor.

Further, in the figure, 5 is a waveguide, 6 is a coaxial line, and 7 is a coaxial center conductor.

In such a configuration, it is necessary to connect the coaxial line 2 shown in FIG. 1a and the coaxial line 6 shown in FIG. 1 with a connecting coaxial line (not shown). (
(not shown), which results in an increase in loss for each conversion (coaxial waveguide conversion, coaxial stripline conversion, connector conversion, etc.), increases cost, and increases the overall size. It had the following drawbacks.

The present invention aims to provide a waveguide-to-microstrip line conversion circuit that prevents losses caused by such many conversions and obtains a small and inexpensive waveguide-to-IJ tube line conversion.

FIG. 2 shows the configuration of an embodiment of the present invention.

In the figure, a is a cross-sectional view, and b is a plan view.

In each figure, 8 is a waveguide, 9 is a microstrip line, and 10
is its center conductor, 11 is a dielectric substrate, 12 is a ground plane, and 13 is a metal wall that is in contact with the ground plate 12 and is used to connect the waveguide and the microstrip line 9 with screws 14.

15 are four parts provided on the H surface 22 of the waveguide so that the external lead-out part of the IJ tube center conductor does not come into contact with the waveguide wall.

In this embodiment, one terminal surface of the waveguide is terminated with a microstrip line, and the central conductor 10 of this microstrip line is electrically short-circuited directly to the E plane at the termination, so that As shown by the broken line, the magnetic field distribution of the waveguide 8 and the magnetic field distribution of the microstrip line 9 are smoothly coupled, and the length 1 of the strip center conductor 10 in the cross section of the waveguide is set to an appropriate length, e.g. When λg is the wavelength on the microstrip line, if the length is chosen to be λg/2, the conversion between the waveguide 8 and the microstrip line 9 can be performed with good matching, and the microstrip line inside the waveguide can be Wave signals can be efficiently transmitted to microstrip lines.

In addition, if the length of the part 1 of the strip center conductor is selected to be close to λg/2, the point where the strip center conductor 10 and the waveguide H plane intersect is located at the very edge of the short-circuit plane, as shown in FIG. Since they can be placed close to each other, it is possible to minimize the size of the concave portion of the waveguide 15, thereby suppressing disturbances in the waveguide mode and improving conversion efficiency.

In addition, the configuration itself is very simple, just cutting one side of the H surface of the waveguide end into a concave shape approximately equal to the thickness of the microstrip line and providing a screw hole, so it is easy to manufacture and inexpensive. be.

FIG. 3 shows another embodiment, in which a second microstrip line 16 is brought into close contact with the H surface of the waveguide, and the first microstrip line 9 and the respective center conductors 10 and 17 are made of metal. The connection is made by connecting with a jumper 21.

With this configuration, if the waveguide signal is taken out to the microstrip line 16 on the H plane and a microwave active element and a filter are configured in this microstrip line 16, a microwave amplifier, mixer circuit, etc. can be configured. Overall, it is possible to form a very simple and compact microwave transmitter/receiver.

In addition, in the figure, 18 is a dielectric substrate, and 19 is a ground plane.

In this embodiment, the end of the center conductor is electrically connected to the E plane via a ground plane.

As described above, according to the present invention, it is possible to efficiently transmit signals from a waveguide to a microstrip line, and it can be manufactured at low cost due to its extremely simple configuration. It is also possible to form .

[Brief explanation of the drawing]

FIG. 1 is a perspective view and a cross-sectional view showing the conversion section of a conventional waveguide-to-microstrip line conversion circuit, FIG. 2 is a cross-sectional view of a main part showing one embodiment of the present invention, and FIG. FIG. 3 is a sectional view of a main part showing an example. 8...Waveguide, 9...First microstrip line, 16...Second microstrip line, 10°17...Strip center Conductor, 12.19...Ground plane.

Claims (1)

[Scope of utility model registration request] One end of a waveguide composed of an E plane and an H plane is terminated with a microstrip line, and the microstrip line in the waveguide is
The center conductor of the IJ tube line is arranged parallel to the E plane of the waveguide, perpendicular to the H plane, and at the center with respect to the E plane at a predetermined length, and one end is connected to the waveguide. A recess is formed in the H-plane end of the waveguide facing the external lead-out part of the center conductor, and the waveguide signal is extracted from the external lead-out part. A waveguide-microstrip line conversion circuit characterized by converting a waveguide line and a strip line.