JPS62216402A - Concentrated constant type circulator and isolator - Google Patents

Abstract

PURPOSE:To obtain an optimum thin structure of less insertion loss by having specific relations between the thickness of an upper soft magnetic body and the diameter of a permanent magnet. CONSTITUTION:If the insertion loss and the ratio ti/Dm of a thickness (ti) of the upper soft magnetic body to a diameter Dm of the permanent magnet should be read along ordinates and abscissas respectively, the insertion loss is reduced quickly in accordance with increase of (ti) when Dm is constant. Consequently, the insertion loss is about <=0.6dB and practicability is attained if ti>=0.01Dm is true when the thin structure is used. Thus, a small-sized concentrated constant type circulator and isolator sized concentrated constant type circulator and isolator of small loss is obtained if ti>=0.01Dm is made true in case of the very simple thin structure.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in compact lumped constant circulators and isolators used in the VHF, UHF and microwave bands.

Lumped constant circulators and lumped constant isolators, etc., are the most important components of microwave equipment and are used in a wide range of microwave fields for purposes such as protecting transistors during high-power operation, matching between legs, and removing unnecessary radiation. .

With the recent dramatic downsizing of other microwave elements, the space occupied by circulators and isolators in the entire microwave device has become quite noticeable.

For example, in some types of devices, it is not uncommon for these space factors to exceed 50%. Furthermore, in terms of the overall cost of the microwave device, the prices of the circulator and isolator account for a considerable amount.

For this reason, demands for smaller size, lower cost, and wider bandwidth for circulators and isolators are becoming stronger day by day. The present invention provides a lumped constant type circulator to meet the demands of the industrial world for downsizing and lowering the price.
This paper relates to structural improvements to isolators.

Generally, the structure of conventional circulators and isolators is as follows:
As shown in FIG. 1, two permanent magnets 3a are placed inside the case 1 to serve as both a magnetic circuit and an electrical shield.
, 3b are attached above and below, and the ferrite core 6 and the center conductor 7 are surrounded by the shield Fi5 exactly in the central space,
It is also placed on the grounding stand 4 via an insulating material 15. Further, the upper permanent magnet 3b is moved vertically by the rotating screw 2, and the magnetic field applied to the ferrite core 6 is finely adjusted. However, in lumped constant type circulators and isolators, approximately 10% of the power is generally lost in the ferrite core 6, but in conventional products with the above structure, this loss heats the ferrite core and changes the characteristics of the element. There was a drawback to that.

In order to solve the above-mentioned problems, the present inventors have proposed that one or more ferrite cores 6 and two or more center conductors 7 are housed on the lower soft magnetic body 10, as shown in FIG. A simple shield plate 5 is placed close to the center of the upper part of the lower soft magnetic body 10, and a permanent magnet 9 is placed on the top of the ferrite core 6 in close contact with the shield plate 7 and the upper soft magnetic body. 8 and 12 are magnetic shunt steel for compensating temperature characteristics. 13 is a flat plate type dummy.

This structure is called a thin structure because it is thinner than the conventional structure. This thin structure is represented by the basic configuration shown in Figure 3, and further investigation revealed that there is a special relationship between each variable shown in the figure in order to obtain the desired characteristics to withstand use. This became clear.

In the figure, Di, Dl, DO, and De represent the diameters of the upper soft magnetic material, permanent magnet, ferrimagnetic material, and lower soft magnetic material, respectively, and ti, tm, tg, and te represent the respective thicknesses, and t is This is the distance between the upper soft magnetic material and the lower soft magnetic material, and is the sum of the thickness ts of the shield plate, the thickness tc of the center conductor, and the thickness tg of the ferrimagnetic material.

An object of the present invention is to provide an optimal thin structure that reduces insertion loss in the lumped constant circulator and isolator described above.

In order to achieve the above object, the present invention applies a DC magnetic field to one or more ferrimagnetic materials (diameter = DQ, thickness = 10), and uses two soft magnetic materials as a method for applying the DC magnetic field. A lumped constant circulator having a configuration in which the ferrimagnetic material housed in a shield plate and two or more center conductors are arranged between them, and a permanent magnet is arranged from the outside of either one of the soft magnetic materials. The isolator is characterized in that it has a structure satisfying the relationship ti≧0.01Dm, where ti is the thickness of the upper soft magnetic body and On+ is the diameter of the permanent magnet.

Hereinafter, the present invention will be explained in detail according to examples.

FIG. 4 is a diagram showing the results of the first example of the present invention. When the vertical axis is the insertion loss and the horizontal axis is the ratio Di/Da of the thickness ti of the upper soft magnetic body and the diameter DI11 of the permanent magnet, D
Under the condition that +m is constant, the insertion loss decreases rapidly as ti increases. From this result, when using a thin structure, if the relationship ti≧0.01Dm, the insertion loss will be approximately 0.6 dB or less, which can be used for practical purposes, but if the thickness of the upper soft magnetic body is less than this, the insertion loss It can be seen that the loss increases and it becomes unusable.

As explained above in detail using the first embodiment of the present invention, in a thin structure with an extremely simple structure, ti≧0, 01Dm
By doing so, it is possible to obtain a compact, low-loss lumped constant type circulator and isolator. It is clear from this that the effects of the present invention are significant.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a conventional product, FIG. 2 is a sectional view of a known isolator with a thin structure, FIG. 3 is a basic thin structure diagram, and FIG. 4 is a structural diagram of an embodiment of the present invention. FIG. 3 is a diagram showing the relationship between the dimensions of . +-7 t5 grandson Ω person Une enters I-fii sa9〉h6
f 1-3 figure

Claims (1)

[Claims] One or more ferrimagnetic materials (diameter = D_G, thickness = t_
G) applying a DC magnetic field, and as a method for applying the DC magnetic field, the ferrimagnetic material housed in a shield plate and two or more center conductors are arranged between two soft magnetic materials, In the lumped constant type circulator and isolator, in which a permanent magnet is arranged from the outside of either one of the soft magnetic bodies, when the thickness of the upper soft magnetic body is t_i and the diameter of the permanent magnet is D_m. t_i≧0
．． A lumped constant circulator and isolator characterized by having a structure having a relationship of 01D_m.