JPS609362B2 - non-reciprocal circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention generally relates to non-reciprocal circuits, and more particularly to non-reciprocal circuits for use in integrated circuits in high frequency bands above the millimeter wave band.

The non-reciprocal circuit according to the present invention can be used as an isolator or circulator used in communication line repeaters and broadcasting equipment.

Conventionally proposed non-reciprocal circuits are generally realized by inserting a magnetic material into a waveguide made of a metal conductor.

However, in millimeter wave integrated circuits and optical integrated circuits, the use of metal waveguides is undesirable because it increases loss. Therefore, conventional non-reciprocal circuits using metal waveguides are essentially unsuitable for use in high frequency bands above the millimeter wave band. On the other hand, as a non-reciprocal circuit that does not use a metal waveguide, a non-reciprocal circuit that uses a magnetic material and an anisotropic crystal (for example, Lino 03) is developed by S. It was published several years ago by Wang and Wanen. However, this technique has difficult problems, such as the degree of adhesion between the magnetic material and the anisotropic crystal, and the necessary machining precision of 1/1M of the wavelength. Furthermore, it is difficult to create a combination of magnetic material and anisotropic crystal in an integrated circuit format. As described above, it is difficult to use conventional non-reciprocal circuits in an integrated circuit format that can be used in millimeter wave bands and optical wave bands.

Therefore, the present invention is intended to improve the above-mentioned drawbacks of the conventional technology, and its purpose is to provide a millimeter-wave band that does not have strict requirements regarding the machining accuracy of circuit dimensions and can be configured without using metal waveguides or anisotropic materials. Another object of the present invention is to provide a non-reciprocal circuit suitable for use in the optical waveband and in integrated circuit format. The feature of the present invention for achieving this purpose is that, by applying an external magnetic field to a rectangular magnetic body, the magnetic body is made to propagate edge-guided mode waves. A non-reciprocal circuit is obtained by adding an electromagnetic wave absorber to the body or by making the magnetic material into a radiating shape. This will be explained in detail below with reference to the drawings. FIG. 1 shows the structure of the main part of a non-reciprocal circuit according to the present invention, and reference numeral 1 is an elongated magnetic material having a substantially rectangular cross section, and is made of, for example, ferrite. 2 is a dielectric material surrounding the magnetic material 1, which may be air or vacuum in special cases.

FIG. 2 shows an experimental setup for demonstrating that edge-guided mode waves can exist in the waveguide shown in FIG. 1. Reference number 1 is the magnetic waveguide shown in FIG. 5 is a magnet for applying a magnetic field to the magnetic waveguide 1, and 5 is a non-reflection load.

Figure 2 shows the magnetic field distribution in the width direction of the magnetic waveguide 1 (in the depth direction of the paper) when an electromagnetic wave was emitted from the electromagnetic horn 3 and an appropriate magnetic field was applied and released in an experiment that took about 1 day and 2. is measured using a small antenna as a probe. The measurement results are shown in Figure 3. Here, the horizontal axis is the distance in the width direction of the magnetic waveguide,
The one-dot chain line indicates the center of the magnetic waveguide, and a pair of perpendicular dotted lines indicate the range where the magnetic waveguide exists. In FIGS. 2 and 3, when there is no magnetic field in the magnetic waveguide (Ho
There is a so-called surface wave on the dielectric line, and its distribution is as shown by the solid line in FIG. 3, with the magnetic field being maximum at the center of the waveguide.

When the magnitude of the magnetic field (Hoc) is an appropriate value, the energy distribution on the waveguide is biased, and when the direction of the magnetic field (Hoc) is reversed, the energy distribution on the waveguide is also reversed. In Figure 3, it is the day. c=0.2 Oersted, 10.
2 Oersted, 4000 Oersted, and -400
The case of 0 Oelsted will be exemplified. The experimental frequency is 1
Yesterday 2, the change in frequency is theoretically unrelated to the distribution of energy on the waveguide. See you tomorrow. Depending on the value of c, the maximum point of the energy distribution may be located inside the waveguide rather than at the end of the waveguide. This point is one of the special features of the present invention; in the microwave band edge guided mode in a waveguide with a conventional metal conductor, if Hoc≠0, the maximum point of energy always exists at the end of the waveguide. do. As described above, the phenomenon in which the energy distribution changes when a magnetic field is applied to a magnetic waveguide was first revealed by the present inventor, and the non-reciprocal circuit according to the present invention utilizes this phenomenon.

Note that the propagation mode in the magnetic waveguide according to the present invention is EH, . , EH, mode exists, so there is a large margin in the accuracy of the circuit dimensions, and the characteristics will not deteriorate due to manufacturing errors. FIG. 4 shows an embodiment of the isolator according to the present invention, in which an electromagnetic wave absorber 6 (a film made by oxidizing the metal surface or carbon) is added to one side of the magnetic waveguide 1.

When a magnetic field Hoc is applied, a wave traveling from A to B is not affected by the absorber 6 because the maximum point of energy is shifted to the right end when looking from A to B. Since the maximum point of energy of the wave propagating to is shifted to the left end when looking from A to B, it is absorbed by the absorber 6 located at the left end.In other words, a unidirectional waveguide, that is, an isolator is formed. FIG. 5A shows an embodiment of a circulator according to the present invention, in which three magnetic waveguides as shown in FIG. 1 are radially coupled.

The wave from Sekiguchi (#1) passes through the right end of the circuit and opens □ (#
2), the wave from Sekiguchi (#2) is similar to Sekiguchi (#3).
), and the wave from open □ (#3) similarly opens □ (#1
). Therefore, a circular operation is performed.
Generally, when N magnetic waveguides are coupled radially, the wave from Sekiguchi (#1) passes through the right end of the circuit and exits to Sekiguchi (#2), as shown in Figure 5B. , Sekiguchi (#2
) similarly goes out to open □ (#3). In this way, generally the wave from open□(#i) is from open□(#i11)
The wave from the last opening (#N) is the closing one (#1).
I will be appearing in A circulator operation is therefore performed. FIG. 6 shows an example of the configuration of an isolator integrated into an integrated circuit using electromagnetic materials.

Reference numeral 7 designates an integrated circuit board, which is a flexible body; 8, a ridge-shaped waveguide made of a magnetic material formed on the board; and 9, an electromagnetic wave absorber placed on one side of the waveguide 1.

FIG. 7 shows another example of the structure of an isolator integrated circuit using a magnetic material.

1. An embedded waveguide made of a magnetic material is formed on a part of the surface of the substrate 7. Reference numeral 11 is an electromagnetic wave absorber attached to the substrate 7 so as to cover the waveguide 10.

FIG. 8 shows an example of the configuration of a circulator formed into an integrated circuit using a magnetic material.

Here, 12 is a waveguide made of a magnetic material and having three terminals configured in a ridge shape on the substrate 7. The operating principle of the configuration examples shown in FIGS. 6 to 8 is the same as that of FIG. 4 or 5. As explained in detail in the examples above, the present invention was made possible by the discovery that edge-guided mode waves can exist in a magnetic waveguide to which a magnetic field is applied. Since a universal crystal is not used, there are no strict requirements for machining accuracy, and since it can be formed on a magnetic material or a magnetic substrate, it is suitable for an integrated circuit format.

Although the non-reciprocal circuit according to the present invention can be used in any frequency band, it can particularly exhibit its characteristics in the millimeter wave band or the optical wave band.

[Brief explanation of the drawing]

Figure 1 is an example of the structure of the main part of a non-reciprocal circuit according to the present invention, Figure 2 is an example of the configuration of an experimental apparatus for confirming the operation of the present invention, and Figures A and B are experiments using the apparatus shown in Figure 2. Example results,
FIG. 4 shows an embodiment of the isolator according to the present invention, FIG. 5A
6 shows another embodiment of the isolator according to the invention, FIG. 7 shows a further embodiment of the isolator according to the invention, and FIG. 8 shows an embodiment of the circulator according to the invention. This is another example. 1, 8, 10, 12; magnetic waveguide; 2; dielectric; 3;
Electromagnetic horn, 4; Magnet, 6; Non-reflective load, 6, 9, 11
; Electromagnetic wave absorber; 7; Integrated circuit board. Fig./Fig. Murasaki Fig. 2 Tsutomu Fig. 3 'A' Fig. 3 'B) Fig. 4 Shig 5 Fig. (A) Fig. 5 Fig. 5 (B) Fig. 5 Fig. 7 Rust Fig.

Claims (1)

[Scope of Claims] 1. A substrate made of a dielectric material, a waveguide made of an elongated magnetic material with a substantially rectangular cross section provided on the substrate, and a magnetic field applied in a direction perpendicular to the longitudinal direction of the magnetic material. 1. A non-reciprocal circuit comprising: a device for propagating edge guided mode waves; and an electromagnetic wave absorber provided on one piece in the longitudinal direction of the magnetic body. 2. A substrate made of a dielectric material, a waveguide made of three or more elongated magnetic materials with a substantially rectangular cross section, and a waveguide made of three or more elongated magnetic materials provided on the substrate, and a magnetic field applied in a direction perpendicular to the longitudinal direction of each magnetic material to create edge guide mode on the magnetic materials. 1. A non-reciprocal circuit comprising: a device for propagating a magnetic wave; and a waveguide made of a magnetic material for radially coupling the magnetic materials.