JPH0219643B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a distributor/mixer used for distributing or mixing high frequency radio waves.

[Prior Art and Its Disadvantages] Conventionally, there are distributors having configurations as shown in FIGS. 3 to 5. 3 is a Wilkison type distributor, FIG. 4 is a directional coupler type distributor, and FIG. 5 is a hybrid ring type distributor. In these distributors, 11 is an input terminal, and 12 and 13 are distribution terminals, respectively.

However, in these distributors, the distribution terminal 1
The disadvantage is that the coupling attenuation between 2 and 13 is usually only about 20 to 30 dB. Furthermore, even when finely adjusted and manufactured, the limit was to achieve a coupling attenuation of about 40 dB.

Furthermore, in order to obtain an inter-terminal coupling attenuation of 60 to 70 dB or more, conventionally the method of using isolators 14 to 17 as shown in Figure 6 has been often used, but as the size increases, The drawback was that it was very expensive.

[Object of the Invention] The present invention was made in view of the above-mentioned circumstances, and its purpose is to provide an inexpensive and small-sized distributor/mixer that can easily obtain an inter-terminal coupling attenuation of 60 to 70 dB with simple adjustment. Our goal is to provide the following.

[Summary of the Invention] When the distributor/mixer according to the present invention is used, for example, as a distributor, a sub-circuit consisting of a series circuit of a coupling element and a phase-shifting element is provided between the distribution terminals to prevent leakage radio waves passing through the main circuit. The radio waves passing through the sub-circuit and the same amplitude,
A high coupling attenuation between distribution terminals of 60 to 70 dB or more is obtained by synthesizing the signals with reverse phase shifts and canceling each other out.

[Embodiment of the Invention] Hereinafter, an embodiment in which the present invention is used as a distributor will be described with reference to the drawings. In FIG. 1, 21 indicates an input terminal, and 22 and 23 each indicate a distribution terminal. Further, 29 and 30 are connection points between the main circuit and the sub circuit. Input terminal 21 and connection point 29, 3
A main circuit 24 is provided between the distribution terminal 2 and the distribution terminal 2.
A subcircuit 25 is provided between 2 and 23. The main circuit 24 includes a line 24a having a length of a quarter wavelength,
24b and a balance resistor 24c. On the other hand, sub circuit 2
5 is a variable coupling capacitor 26 and a variable phase shifter 27
and a variable coupling capacitor 28 in series.

In such a distributor, for example, input terminal 2
When a 50Ω load is connected to the terminal 1, when a high frequency radio wave is inputted from the distribution terminal 22, a leakage radio wave that is normally attenuated by 20 to 30 dB is outputted to the distribution terminal 23 via the main circuit 24.

In the present invention, the coupling degree of the variable coupling capacitors 26 and 28 of the sub-circuit 25 is adjusted so that the amplitude is the same as that of this radio wave, and the variable phase shifter of the sub-circuit 25 is adjusted so that the two radio waves have the opposite phase shift. 27. That is, from the distribution terminal 22 to the main circuit 24
The radio waves that passed through the subcircuit 25 and the radio waves that passed through the subcircuit 25 are combined at the distribution terminal 23 with the same amplitude and opposite phase shift,
They cancel each other out, resulting in 60 to 70 dB
As described above, a very large amount of coupling attenuation between terminals can be obtained.

FIG. 2 is a characteristic diagram of the amount of coupling attenuation between terminals, comparing the conventional distributor and the distributor of the present invention. In the figure, a shows an example of the characteristic in the conventional case, and b shows an example of the characteristic in the case of the present invention.

In the above embodiment, the variable coupling capacitors 26 and 28 are used as elements constituting the sub-circuit 25.
Although a variable phase shifter 27 and a variable phase shifter 27 are used, other elements may be used as long as the same effect can be obtained. Moreover, each element does not necessarily have to be a variable element, and of course may be a fixed element.

Further, in the above embodiment, an example of a Wilkinson type distribution circuit in which the present invention is applied to a distributor has been described, but the present invention is not limited to this, and a directional coupler,
The same applies to distribution circuits constructed from rat trace circuits, hybrid rings, and the like. In addition,
By using the input terminal 21 as a mixing terminal and the distribution terminals 22 and 23 as input terminals, it is also possible to use it as a mixer.

[Effects of the Invention] As described above, according to the present invention, with a simple configuration,
A distributor/mixer that can obtain a large amount of coupling attenuation between terminals can be realized.

Furthermore, since there is no need to add expensive parts such as an isolator, a small and inexpensive product can be obtained.

[Brief explanation of drawings]

FIG. 1 is a circuit configuration diagram showing a distributor according to an embodiment of the present invention, FIG. 2 is a terminal-to-terminal coupling attenuation characteristic diagram comparing the present invention and a conventional distributor, and FIGS. Each figure is a circuit configuration diagram showing a conventional distributor. 21...Input terminal, 22, 23...Distribution terminal, 24
...Main circuit, 25...Subcircuit, 26, 28...Variable coupling capacitor, 27...Variable phase shifter.

Claims (1)

[Claims] 1. A first terminal that serves as an input or output terminal for high-frequency radio waves, second and third terminals that serve as output or input terminals for high-frequency radio waves, and the first terminal and the second terminal. connected between the terminal and the third terminal,
the second for distributing or mixing the high frequency radio waves;
A main circuit having a coupling attenuation between a terminal and a third terminal, and a series circuit of a coupling element and a phase shift element, and is configured to prevent leakage of radio waves from the second terminal to the third terminal of the main circuit. A distributor/mixer comprising a sub-circuit for canceling the level. 2. The distributor/mixer according to claim 1, wherein a variable phase shifter is used as a phase shift element of the sub-circuit.