JPS63164502A - Microwave bipolar double-throw switch - Google Patents

Abstract

PURPOSE:To constitute the titled switch of the small number of switching elements on plane structure by connecting signal terminals mutually through distribution constant lines and two switching elements. CONSTITUTION:Two pairs of signal terminals 1, 2 and 3, 4 are connected to each other respectively through half-wavelength (or their integertimes length) lines 8, 9 having equal characteristic impedance and their intermediate points are connected to 1/4 wavelength (or its odd-numbers length) line 6. The synergistic average of the characteristic impedance of the line 6 and that of the line 5 or 7 is set up to the characteristic impedance of the line 8 or 9 and the intermediate point of the lines 8, 9 is earthed through switching elements 10, 11. When the elements 10, 11 are turned on, a parallel mode is set up, and at the time of turning off the elements 10, 11, a cross mode is set up. Consequently, the simple structure consisting of one plane can be obtained and integration can be easily executed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a microwave double-pole double-throw switch, and more particularly to a double-pole double-throw switch suitable for microwave planar circuits.

[Conventional technology]

An example of a conventional double-pole double-throw switch is shown in FIG.

In FIG. 2, 51 to 54 represent signal terminals, 55 to 58 switching elements, and 59 a three-dimensional intersection.

When switching elements 55 and 56 are ON and switching elements 57 and 58 are OFF, terminals 51 and 52 and terminals 53 and 54 are connected, respectively (this state will be referred to as parallel mode).

In addition, when the switching elements 55 and 56 are OFF and the switching elements 57 and 58 are ON, the terminal 51 and the terminal 54
, terminals 52 and 53 are connected (this state will be referred to as cross mode).

[Problem that the invention seeks to solve]

In the conventional double-pole double-throw switch as mentioned above, the circuit manufacturing process is complicated because the intersection is three-dimensional.
In addition, mechanical strength and vibration resistance are poor.

■0N10FF caused by stray capacitance at grade crossings
There is a deterioration in the degree of separation.

■A large number of switching elements (four) are required.

There were drawbacks such as.

In view of these conventional problems, the present invention has a planar structure,
Another object of the present invention is to provide a double-pole, double-throw switch that can be configured with a small number of switching elements.

[Means for solving problems]

According to the invention, the above objects are achieved by the means specified in the claims.

In other words, the microwave double-pole double-throw switch of the present invention has the 4I feature of connecting signal terminals using a distributed constant line and two switching elements, and eliminates the need for the conventionally required grade-level intersection. , which is different from conventional devices in that it can form a double-pole, double-throw switch with a single-plane structure.

〔Example〕

Figure tI&1 is a diagram showing an embodiment of the present invention, and shows the configuration of a microwave planar circuit double-pole double-throw switch,
1 to 4 represent signal terminals, 5 to 7 represent quarter wavelength lines, and 8 and 9 represent half wavelength lines.

A track 6 connects the midpoints of a track 8 and a track 9.

These midpoints are each grounded via a switching element 10.11. The line 5 and the line 7 have the same characteristic impedance, which is designated as Za. The line 8 and the line 9 have the same characteristic impedance, which is designated as zb. railroad track 6
Let Zc be the characteristic impedance of

The characteristic impedances of these lines have a geometric mean relationship, that is, a relationship shown in equation (1).

zb=FT “77 ・・・・・・・・・・・・ (1
) The operation of the microwave double-pole double-throw switch of this embodiment will be explained below.

First, when the switching elements 10.11 are turned ON (conducting or short-circuited), the lines 8.9 each become 1/4 of the two lines.
The wave becomes a short-circuit stub.

Therefore, the track 8.9 seen from the track 5 and the track 7
The impedance of becomes infinite, and eventually all the microwave signal current from terminal 1 flows to terminal 2 through line 5.
It will be done.

Similarly, all microwave signal current from terminal 3 is transferred to line 7.
It flows to terminal 4 through. In this way, the present circuit becomes in a state equivalent to the parallel mode in the circuit of FIG.

Next, it will be explained below that when the switching elements 1.0 and 11 are turned off (cut off or opened), the main circuit enters a state equivalent to the crossing mode in the circuit of FIG. 12.

In general, the 7 domitance matrix when considering a 1/4 wave of characteristic impedance Z and the line as a two-terminal pair network is (2)
As shown in the formula.

j in equation (2) is an imaginary unit.

Set the signal voltage at terminals 1 to 4 to ■■2 and ■8, respectively.
, ■, and the signal voltages at the midpoints of the half-covered lines 8 and 9 are Vs and Vs, respectively.

When Kirchhoff's first law is applied to these six nodes and equation (2) is applied to the seven branches, a six-element simultaneous equation, Za Zb Za Zb Za Zb is obtained.

Here, I and ~I are signal currents flowing from terminals 1 to 4, respectively. Equations (7) and (8) are converted into equations (3) to (6
) and eliminate ■, and va to obtain the west terminal admittance matrix Y of this circuit.

Substituting relational expression (1) into this equation results in a diagonal matrix. That is, no coupling occurs between adjacent terminals.

When this west terminal admittance matrix is converted into a four-terminal scattering matrix S in which the signal source and load impedances are multiplied by 2 degrees, the following is obtained.

Especially Z here. In the case of =Za, it becomes. That is, this circuit is matched to a signal source/load impedance equal to Za, and all input signal power is output to diagonal terminals. In this way, the circuit is in cross mode.

〔Effect of the invention〕

As explained above, the micro double-pole double-throw switch according to the present invention has a one-plane structure, which makes it easy to manufacture circuits and incorporate it into integrated circuits, and has excellent mechanical strength and vibration resistance. , high reliability can be achieved. Therefore, it is suitable for switching microwave communication equipment mounted on an artificial satellite, for example.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of the present invention, and FIG. 12 is a diagram showing an example of a conventional double-pole double-throw switch. 1~4.51~54...Signal terminal, 5゜6
．． 7 ・・・・・・ 1/4 length line, 8.9 ・
...Half-wave gcM path, 10. 11. 55-
58...Switching element, 59...
...Grade Intersection Agent Patent Attorney Takayoshi Honma 2 Figure

Claims (1)

[Claims] It has four terminals, and among these four terminals, adjacent terminals (
1) and terminal (2), and terminal (3) and terminal (4), respectively, are connected by a 1/4 wavelength line with equal characteristic impedance or a line (5) or (7) of an odd multiple of the length, and ) and the terminal (3), and the terminal (2) and the terminal (4), respectively, are connected by a line (8) or (9) of half a wavelength or an integral multiple thereof with equal characteristic impedance, and these two lines (8) and The midpoints of each of (9) are 1
/4 wavelength or an odd multiple thereof, and the geometric mean value of the characteristic impedance of the line (6) and the characteristic impedance of the line (5) or (7) is determined as the line (8).
) or (9), and the midpoint of the lines (8) and (9) is grounded via a switching element.