JPH0346563Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a branched MIC circulator constructed by forming a conductor pattern on a ferrimagnetic substrate.

In recent years, there has been a strong demand for the miniaturization of microwave communication equipment, and measures are being taken to make the devices inside the equipment smaller, lighter, and more compact by using microwave integrated circuits. , have been used in many devices together with isolators.

On the other hand, the range in which devices can be converted to MIC has expanded in recent years, and due to the increase in frequency limits, it has extended from the sub-millimeter wave band to the millimeter wave band. However, as the frequency increases, the effects of such effects, such as variations in electrical performance due to variations in MIC manufacturing precision, are becoming too large to be ignored. Therefore,
In order to maintain good electrical characteristics beyond the limits of manufacturing accuracy, it is required to adjust the capacitance of joints and transmission line sections.

Therefore, first, the problems in the conventional prior art will be explained using drawings to clarify the drawbacks.

FIG. 1 is a diagram showing an example of a MIC circulator according to the prior art. FIG. 1 shows an example in which conductor patterns such as joints and transmission lines are formed on a single ferrimagnetic substrate. On the other hand, FIG. 2 shows a second example in which the joint portion is formed on a ferrimagnetic substrate and the transmission line portion is formed on a high dielectric constant dielectric substrate. In Fig. 1, 1 is a ferrimagnetic substrate, 2 is a joint conductor pattern, 3 is a magnet, 4 is a subcarrier,
6 is a transmission line section.

In FIG. 1, the operation of the MIC circulator is determined primarily by the dimensions of the junction conductor pattern and the applied magnetic field provided by the magnet. The applied magnetic field can be varied by moving the magnet up and down. On the other hand, since conductor patterns are often formed using photoetching techniques,
It is difficult to easily change dimensions or improve dimensional accuracy. Therefore, it is necessary to adjust the electrical characteristics by increasing or decreasing the capacitance at the junction and the transmission line. This example is intended to simplify the structure, and has a structure in which a transmission line and the like are provided on a ferrimagnetic substrate that is essential to the circulator. In order to adjust the electrical characteristics, for example, the capacitance component can be increased or decreased by adjusting the transmission line, but since the dielectric constant of the ferrimagnetic substrate is 10 to 16, which is extremely high, minute capacitance adjustments are difficult. However, it has the disadvantage that it is difficult to obtain uniform performance.

The purpose of the present invention is to construct a MIC circulator in which a dielectric substrate with a low permittivity is in contact with a ferrimagnetic substrate, and a transmission line is formed across both substrates. The objective of the present invention is to provide a MIC circulator that provides excellent performance.

The MIC circulator according to the present invention includes a branched MIC circulator body including a first type of transmission line and a second type of transmission line. That is, the main body of the branched MIC circulator is constructed by forming a conductor pattern on a ferrimagnetic substrate and including a first type of transmission line leading to an input/output terminal. On the other hand, the second type of transmission line is connected to the input/output terminal of the MIC circulator body, and is formed on a dielectric substrate having a relative dielectric constant of 1.5 to 5.

Hereinafter, the MIC circulator according to the present invention will be explained in detail with reference to the drawings.

FIG. 2 is a structural diagram showing the MIC circulator according to the present invention. In Fig. 2, 1 is a ferrimagnetic substrate, 2 is a joint conductor pattern, 3 is a magnet, 4 is a subcarrier, 6 is a transmission line section, and 61 and 62 are the first and second types of transmission lines, respectively. , 7 is an inter-substrate connection conductor, and 8 is a low dielectric constant dielectric substrate. FIG. 2 shows a structure in which a second type of transmission line 62 formed on a dielectric substrate 8 having a low dielectric constant is connected to a first type of transmission line 61 on a ferrimagnetic substrate. It is a MIC circulator. Further, as shown in FIG. 2, the ferrimagnetic substrate 1 and the dielectric substrate 8 are formed on the subcarrier 4 so as to be in contact with each other.

According to such a configuration, changes in characteristics due to variations in dimensional accuracy of the joint conductor pattern 2 and the transmission line 61 are caused by capacitance components formed by the subcarrier 4, the dielectric substrate 8, and the transmission line 62. It can be adjusted by reducing it. Since the dielectric substrate 8 has a low dielectric constant, the capacitance component changes slowly with respect to changes in the area of the transmission line 62, and therefore, the capacitance can be easily adjusted.

In addition, the capacity adjustment is specifically explained by Masamitsu Nakajima,
"Microwave Engineering", Morikita Publishing Co., Ltd., 1975, p. 176. As can be seen from the relationship between transmission line width and characteristic impedance shown in Figures 6 and 5, the transmission line width can be changed. It goes without saying that the width of the transmission line 62 in FIG. 2 may be adjusted as appropriate by cutting the transmission line 62 or applying conductive paint to the transmission line 62. According to the configuration of the circulator shown in Fig. 2, the dielectric constant of the dielectric substrate 8 in the capacitance adjustment portion is approximately 1/2 to 1/10 of that of the ferrimagnetic substrate shown in Fig. 1, so the MIC circulator It is also possible to easily make delicate adjustments peculiar to the above, making it easier to obtain uniform electrical characteristics. In particular, in the quasi-millimeter wave frequency band, the effect of equivalent capacitance is large, so the MIC circulator according to the present invention is extremely effective. It goes without saying that the optimal frequencies when using the conventional example shown in FIG. 1 and the MIC circulator of the present invention shown in FIG. 2 are not necessarily the same due to their structural differences.

Although the MIC circulator has been described above, it is clear that similar effects can be obtained with a MIC isolator configured by terminating one terminal of the MIC circulator.

As explained above, by connecting the second transmission line section formed on the dielectric substrate having a low dielectric constant to the first transmission line section formed on the ferrimagnetic substrate, electrical It is easy to adjust and optimize the performance, uniform electrical performance is obtained, and the cost can be reduced by shortening the adjustment factory. Furthermore, since the ferrimagnetic substrate and the dielectric substrate with a low dielectric constant are formed so as to be in contact with each other on a common subcarrier, the circulator is small and has sufficient strength even when applied to the quasi-millimeter wave band. is obtained.

[Brief explanation of the drawing]

FIG. 1 is a structural diagram showing an example of a MIC circulator using a ferrimagnetic substrate according to the prior art. Figure 2 is a structural diagram of the MIC circulator according to the present invention. DESCRIPTION OF SYMBOLS 1... Ferrimagnetic substrate, 22... Junction conductor pattern, 3... Magnet, 4... Subcarrier, 6... Transmission line, 7... Inter-board connection conductor, 8
...Dielectric substrate with low dielectric constant.

Claims (1)

[Scope of utility model registration request] Forming a conductor pattern on a ferrimagnetic substrate,
A branched MIC circulator body configured with a first type of transmission line leading to an input/output terminal, and a dielectric substrate connected to the input/output terminal of the MIC circulator body and having a relative permittivity of 1.5 to 5. a second type of transmission line formed above, and wherein the ferrimagnetic substrate and the dielectric substrate are formed on a common subcarrier so as to be in contact with each other.