JPS6236325Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a waveguide type ferrimagnetic phase shifter that suppresses resonance of unnecessary modes and reduces insertion loss as much as possible.

FIG. 1a is a perspective view of a conventional waveguide-type ferrimagnetic phase shifter that suppresses unnecessary modes.
This phase shifter is composed of a waveguide 1, a ferrimagnetic material 2, a magnetizing conductor 3, a matching dielectric 4, a dielectric plate 5, and a radio wave absorber 6.
A magnetizing conductor 3 drawn out from between the holes parallel to the waveguide H surface and diagonally crossing the waveguide E surface is taken out of the waveguide 1 through a small hole 7 provided in the waveguide E surface tube wall. ,
Further, a dielectric plate 5 coated with or vapor-deposited a radio wave absorber 6 is disposed along the magnetization conductive wire 3 in parallel to the waveguide H surface.

FIG. 1b is a sectional view taken along the line AA in FIG. 1a, and shows a structure in which the magnetizing conductive wire 3 is arranged in the hole 8 of the ferrimagnetic body 2.

FIG. 1c is a cross-sectional view taken along line B-B in FIG. Inside the waveguide, a step 10 is provided to lower the waveguide height.
A structure is shown in which a ferrimagnetic material 2 and a matching dielectric material 4 are arranged so as to be in contact with both walls of the H-plane of the waveguide.

Next, the operation of the conventional phase shifter will be explained. By switching the current flowing through the magnetizing conducting wire 3, the ferrimagnetic material 2 exhibits two different magnetic permeabilities to microwaves. Therefore, by switching the direction of current for an incident wave having a constant phase, a phase difference is created in the transmitted wave, and therefore it operates as a phase shifter.

In a waveguide type Ferrimagnetic phase shifter with this structure,
By using a thin conductor plate 9 on one side of the waveguide H-plane tube wall, the pressure applied to the ferrimagnetic material 2 is reduced, and the ferrimagnetism caused by expansion and contraction due to temperature changes under severe environmental conditions is reduced. This prevents damage to the body 2. Therefore, in order to lower the waveguide height so as to prevent the propagation of unnecessary waveguide modes that degrade the microwave characteristics of the phase shifter, it is difficult to create a step in the thin conductor plate 10. Therefore,
A step 10 is provided only on the other side of the H-plane wall of the waveguide, giving the waveguide a vertically asymmetrical structure.

FIGS. 2a and 2b are perspective views of the conventional phase shifter shown in FIG. 1, respectively, viewed from the top and side.
This figure shows a structure for suppressing the coaxial mode in which the magnetizing conductor 3 is used as an inner conductor and the waveguide 1 is used as an outer conductor, which cannot be suppressed by the method of lowering the waveguide height described above. The magnetizing conductor 3 is made parallel to the waveguide H plane and diagonally intersects the waveguide E plane, and the electric field of the coaxial mode indicated by the broken arrow in Fig. 2a is concentrated on the plane parallel to the waveguide H plane. The dielectric 5 coated with or vapor-deposited a radio wave absorber 6 arranged parallel to the waveguide H surface is brought close to the magnetization conducting wire 3 to effectively absorb the electric field of the coaxial mode.

However, in the above structure, since the waveguide 1 is provided with the step 10 so as to be vertically asymmetric, the electric field that satisfies the boundary condition at this portion is
As shown by the broken arrow in FIG. b, there is not only a component parallel to the E-plane of the waveguide, but also a component parallel to the H-plane of the waveguide. Therefore, in the conventional ferrimagnetic phase shifter, the dielectric plate 5 on which the magnetizing wire 3 and the radio wave absorber 6 are coated or deposited is placed in the region where an electric field having a component parallel to the waveguide H plane exists. is arranged, the electric field component parallel to the waveguide H plane is directly absorbed by the radio wave absorber 6, and is further absorbed by the radio wave absorber 6 after being combined with the magnetization conductor 3, increasing insertion loss. There was a drawback.

In order to solve these drawbacks, this invention aims to effectively suppress only the increase in loss caused by resonance in the coaxial mode by making improvements to the arrangement of the magnetizing conductor 3 and the position where the radio wave absorber 5 is coated or deposited. The drawings will be described in detail below.

FIG. 3 is a perspective view showing an embodiment of this invention, and FIGS. 4a and 4b are enlarged views of the vicinity of the step 8, each of which is a perspective view of the phase shifter from the upper side.
A waveguide H is inserted between the ferrimagnetic material 2 and the matching dielectric material 4.
The magnetizing conductor 3 drawn out parallel to the plane and obliquely to the E plane of the waveguide is passed through a small hole 7 provided in the wall of the E plane of the waveguide where the height of the waveguide is low to the outside of the waveguide 1. Further, a dielectric plate 5 is placed along the magnetization conducting wire 3 in parallel with the waveguide H surface. Furthermore, this dielectric plate 5 has a structure in which a radio wave absorber 6 is coated or vapor-deposited only on the portion inserted into the low-height portion of the waveguide and along the magnetization conducting wire 3.

As shown in Figure 4b, the electric field has a component parallel to the H-plane of the waveguide in areas where the waveguide height is high, and a component that is almost parallel to the H-plane of the waveguide in areas where the waveguide height is low. Therefore, even if the dielectric plate 5 with the radio wave absorber 6 attached is placed only in the low-height portion of the waveguide, the coaxial mode can be efficiently absorbed without causing an increase in insertion loss. .

Therefore, even in a vertically asymmetrical structure, it is possible to suppress the resonance phenomenon due to the coaxial mode without causing loss to the power of the fundamental mode, and it is possible to prevent characteristic deterioration of the phase shifter.

In addition, although the case where the number of magnetization conducting wires 3 is one has been described above, this invention is not limited to this, and can also be applied to a case where there are a plurality of magnetization conducting wires 3.

As described above, in the waveguide type ferrimagnetic phase shifter according to this invention, the waveguide H-plane component of the electric field generated by the step 10 provided on one side of the waveguide H-plane tube wall is located at a position where the waveguide H-plane component does not exist. Magnetizing conductor 3 and radio wave absorber 6
By arranging this, it becomes possible to suppress coaxial mode resonance without causing an increase in loss of passing power, and it is possible to obtain a phase shifter that provides good microwave characteristics.

[Brief explanation of the drawing]

FIG. 1a is a perspective view of a conventional waveguide type ferrimagnetic phase shifter, FIG. 1b is a sectional view taken along line A-A in FIG. 1a,
Fig. 1c is a cross-sectional view taken along line BB in Fig. 1a, Fig. 2a is a perspective view of the vicinity of the step of a conventional waveguide type ferrimagnetic phase shifter seen from above, and Fig. 2b is a FIG. 2 is a perspective view of the part shown in FIG. FIG. 4b is a perspective view of the portion shown in FIG. 4a seen from the side. In the figure, 1 is a waveguide, 2 is a ferrimagnetic material, 3 is a magnetization conductor, 4 is a matching dielectric, 5 is a dielectric plate, 6 is a radio wave absorber, 7 is a small hole on the E side of the waveguide, 8 9 is a ferrimagnetic hole, 9 is a thin conductor plate, and 10 is a step. In the drawings, the same or corresponding parts are denoted by the same reference numerals.

Claims (1)

[Scope of utility model registration request] A magnetizing conductor is passed through the hole in the toroid-shaped ferrimagnetic material, and a matching dielectric is attached to both ends of the ferrimagnetic material. One surface of the waveguide H-plane tube wall is flat and the other surface has a predetermined length. The ferrimagnetic material and the matching dielectric material are arranged so as to be in contact with both walls of the H-plane of the waveguide in a waveguide with steps provided so that the height of the waveguide is lowered. A magnetization guide wire drawn out from between the bodies parallel to the waveguide H plane and diagonally crossing the waveguide E plane was installed on the waveguide E plane tube wall of the waveguide with a low waveguide height. The dielectric plate is taken out of the waveguide through a small hole, and the dielectric plate is placed parallel to the H-plane of the waveguide along the magnetization conductive wire, and the dielectric plate is inserted into the waveguide with a low waveguide height. A waveguide-type ferrimagnetic phase shifter characterized in that a radio wave absorber is coated or vapor-deposited.