JP2001320209A - High frequency hybrid circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To sufficiently reduce a distribution loss deviation without deteriorating an isolation quantity. SOLUTION: This circuit has a ring-shaped configuration cascade connecting a first distribution constant line 10 composed of a distribution constant line with the 1/4 wavelength of a set frequency, second distribution constant line 11 composed of a distribution constant line with the 1/4 wavelength, third distribution constant line 12 composed of a distribution constant line with the 1/4 wavelength, fourth distribution constant line 13 composed of a distribution constant line for the 1/4 wavelength and fifth distribution constant line 14 composed of a distribution constant line with the 1/2 wavelength. By connecting a sixth distribution constant line 15 made into short stub to a first terminal Po, the distribution loss deviation can be sufficiently reduced without deteriorating the isolation quantity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-terminal high-frequency hybrid circuit for synthesizing and distributing high-frequency power.

[0002]

2. Description of the Related Art A rat race circuit has been conventionally known as a typical circuit of a hybrid circuit for synthesizing and distributing high frequency power. Figure 1 shows the configuration of a conventional rat race circuit.
It is shown in FIG. As shown in FIG. 15, the rat race circuit 100 includes a first distributed constant line 110 composed of a distributed constant line having a length of １ ／ wavelength of the wavelength of the set frequency, and a distributed constant line having a length of ４ wavelength. Distributed constant line 111 made of
And a third distributed constant line 112 composed of a distributed constant line having a length of 1/4 wavelength and a fourth distributed constant line 113 composed of a distributed constant line having a length of 3/4 wavelength are cascade-connected. It has a configuration. Then, the first distributed constant line 11
A first terminal Po is derived from a connection point between the first distributed constant line 110 and the third distributed constant line 112, and a second terminal Pa is derived from a connection point between the first distributed constant line 110 and the third distributed constant line 112. 2 distributed constant line 111 and fourth distributed constant line 113
A third terminal Pb is led out from the connection point with. Further, a third distributed constant line 112 and a fourth distributed constant line 113
Is connected to a resistor R.

At this time, a fourth distributed constant line 113 having a length of ／ wavelength, a first distributed constant line 110, a second distributed constant line 111, and a third distributed constant line having length of １ ／ wavelength are provided. 1
The impedance 12 is determined by the power distribution ratio and the load impedance connected to each terminal. As an example, this is a case where a high-frequency signal input from the first terminal Po is distributed to the second terminal Pa and the third terminal Pb at a power distribution ratio of 1: 1, and the impedance of each terminal is 50Ω.
, The result is as shown in FIG. That is, the first distributed constant line 110 to the fourth distributed constant line 1
13 is {2 × 50Ω} 70.711
Ω. The electric phase angle θ of the first distributed constant line 110, the second distributed constant line 111, and the third distributed constant line 112
Is set to θ = 90 °, and the electric phase angle θ of the fourth distributed constant line 113 is set to θ = 270 °.

In the rat race circuit 100, when a high-frequency signal is input from the first terminal Po, a high-frequency signal whose power is distributed, for example, at a ratio of 1: 1 is output from the second terminal Pa and the third terminal Pb. . The high frequency signal is not consumed by the resistor R. This means that, at the second terminal Pa and the third terminal Pb, the high-frequency signal input from the first terminal Po and propagated by the two propagation paths arrives in phase, and the resistance R First
This is because the high-frequency signals input from the terminal Po and propagated by the two propagation paths arrive in opposite phases.
Further, since the rat race circuit 100 is a reversible circuit, the high-frequency signals input from the second terminal Pa and the third terminal Pb are combined and output from the first terminal Po.

The rat race circuit 100 is shown in FIG.
As is clear from FIG. 5, the circuit is not vertically symmetric. From this, the frequency of the high-frequency signal distributed and output from the second terminal Pa and the third terminal Pb is
It is expected that the distribution deviation of the power distribution ratio increases as the distance from the set frequency increases. Therefore, as a symmetric hybrid circuit capable of distributing and combining high-frequency power, there has been known a hybrid circuit proposed by Ullrich H. Gysel as a background art in US Pat. No. 4,163,955. FIG. 16 shows this hybrid circuit. Hereinafter, in this specification, the hybrid circuit shown in FIG. 16 is referred to as a Gaisel hybrid circuit.

A Gysel hybrid circuit 200 shown in FIG. 16 includes a first distributed constant line 210 composed of a distributed constant line having a length of １ ／ wavelength of a set frequency, and a distributed constant having a length of １ ／ wavelength. Second distributed constant line 21 composed of a line
1, a third distributed constant line 212 composed of a distributed constant line having a length of 1/4 wavelength, a fourth distributed constant line 213 composed of a distributed constant line having a length of 1/4 wavelength, and a It has a ring-like configuration in which a fifth distributed constant line 214 composed of a distributed constant line having a length is cascaded. And the first
A first terminal Po is derived from a connection point between the distributed constant line 210 and the second distributed constant line 211, and the first distributed constant line 2
A second terminal Pa is derived from a connection point between the third distributed constant line 212 and the third distributed constant line 212, and a third terminal Pb is derived from a connection point between the second distributed constant line 211 and the fourth distributed constant line 213. . Further, a first resistor R1 is connected to a connection point between the third distributed constant line 212 and the fifth distributed constant line 214, and the fourth distributed constant line 213 and the fifth distributed constant line 214
Is connected to a second resistor R2.

At this time, the fifth distributed constant line 214 having a length of 波長 wavelength, the first distributed constant line 210, the second distributed constant line 211, and the third distributed constant line having length of １ ／ wavelength 2
The impedance of the twelfth and fourth distributed constant lines 213 is determined by the power distribution ratio, the load impedance connected to each terminal, and the resistance values of the first resistor R1 and the second resistor R2. As an example, this is a case where a high-frequency signal input from the first terminal Po is distributed to the second terminal Pa and the third terminal Pb at a power distribution ratio of 1: 1. Resistance R1, the second resistance R2
Is set to 50Ω, VSW from each terminal
When the parameters are selected so that the R characteristic has as wide a band as possible, the result is as shown in FIG. That is, the impedances Z1 and Z2 of the first distributed constant line 210 and the second distributed constant line 210 are {2 × 50Ω} 70.711
And the impedances Z3 and Z4 of the third distributed constant line 212 and the fourth distributed constant line 213 are 50.000.
And the impedance Z of the fifth distributed constant line 214.
5 is about 21.200Ω. Note that the first distributed constant line 210, the second distributed constant line 211, and the
The electric phase angle θ of the third distributed constant line 212 and the fourth distributed constant line 213 is θ = 90 °, and the electric phase angle θ of the fifth distributed constant line 214 having a length of 波長 wavelength is θ = 180
°.

In this Geisel hybrid circuit 200, when a high-frequency signal is inputted from the first terminal Po,
From the second terminal Pa and the third terminal Pb, for example, 1:
The high-frequency signal to which the power is distributed in 1 is output. The high frequency signal is not consumed by the first resistor R1 and the second resistor R2. This is because, at the second terminal Pa and the third terminal Pb, the high-frequency signal input from the first terminal Po and propagated through the two propagation paths arrives in phase, and the first resistor R1 And the second resistor R2
In this case, the high-frequency signal input from the first terminal Po and propagated through the two propagation paths arrives in opposite phases. Also, Gaicel's hybrid circuit 2
Since 00 is a reversible circuit, the high-frequency signals input from the second terminal Pa and the third terminal Pb are combined and output from the first terminal Po.

[0009]

In the above-described rat race circuit 100, the first terminal Po and the second terminal Pa
The impedance of the first to fourth distributed constant lines 110 to 113 when the power distribution ratio is used as a parameter, and the return loss characteristics, the insertion loss characteristics, The isolation characteristics will be described below. This is a case in which a high-frequency signal input from the first terminal Po is distributed to the second terminal Pa and the third terminal Pb at a power distribution ratio of 1: 1, and when the impedance of each terminal is set to 50Ω. The race circuit 100 is shown in FIG. In this case, the impedance of the first distributed constant line 110 to the fourth distributed constant line 113 constituting the rat race circuit 100 is about 70.711Ω as described above.
Further, the first distributed constant line 110 and the second distributed constant line 11
1, the electric phase angle θ of the third distributed constant line 112 is θ = 9
0 °, and the electrical phase angle θ of the fourth distributed constant line 113
Is set to θ = 270 °.

The return loss characteristic, the insertion loss characteristic, and the isolation characteristic of the rat race circuit 100 in the case of the parameter values shown in FIG. 17 are set to 750 MHz to 1250 MHz, which is a 50% band with a center frequency of 1000 MHz. FIG. 19 shows a chart of the characteristics in the above. Referring to FIG. 19, the return loss characteristics of each terminal and the isolation characteristics between the first terminal Pa and the second terminal Pb are 875 MHz or more, which is a 25% band.
Good characteristics are obtained at 1125 MHz. Referring to the insertion loss characteristic, the insertion loss of the first terminal Pa and the second terminal Pb is 3.01 dB at the center frequency of 1000 MHz. In the 20% band, the insertion loss of the first terminal Pa is 2.85 dB, the insertion loss of the second terminal Pb is 3.24 dB, and the distribution loss deviation is 0.39 dB. Furthermore, in the 25% band, the insertion loss of the first terminal Pa is 2.77 d.
B, the insertion loss of the second terminal Pb is 3.38d
B, and the distribution loss deviation reaches 0.61 dB. This distribution loss deviation is about 20% of the insertion loss of 3.01 dB at the center frequency, and is a large deviation that cannot be ignored.

Next, the rat race circuit 10 shown in FIG.
0, the high frequency signal input from the first terminal Po is divided into a second terminal Pa and a third terminal P at a power distribution ratio of 1: 3.
b, and the rat race circuit 100 when the impedance of each terminal is set to 50Ω is shown in FIG.
Shown in In this case, the first distributed constant line 110 and the fourth distributed constant line 11
3 has an impedance of 100.000Ω, and the impedance of the second distributed constant line 111 and the third distributed constant line 112 is approximately 57.735Ω. The electric phase angle θ of the first distributed constant line 110, the second distributed constant line 111, and the third distributed constant line 112 is set to θ = 90 °,
The electric phase angle θ of the fourth distributed constant line 113 is θ = 270
°.

The return loss characteristic, the insertion loss characteristic, and the isolation characteristic of the rat race circuit 100 in the case of the parameter values shown in FIG. 18 are set to 750 MHz to 1250 MHz, which is a 50% band with a center frequency of 1000 MHz. FIG. 20 shows a chart of the characteristics in the above. Referring to FIG. 20, the return loss characteristics of each terminal and the isolation characteristics between the first terminal Pa and the second terminal Pb are in the range of 875 MHz which is a 25% band.
Good characteristics are obtained at 1125 MHz. Referring to the insertion loss characteristics, at a center frequency of 1000 MHz, the insertion loss of the first terminal Pa is 6.02 dB, and the insertion loss with the second terminal Pb is 1.25 dB. And 20
In the% band, the insertion loss of the first terminal Pa is 5.
74 dB, the insertion loss of the second terminal Pb is 1.
38 dB, and the distribution loss deviation is 0.41 dB. Further, in the 25% band, the insertion loss of the first terminal Pa is 5.58 dB, the insertion loss of the second terminal Pb is 1.47 dB, and the distribution loss deviation reaches 0.66 dB. This distribution loss deviation is a large distribution loss deviation that cannot be ignored.

Next, the rat race circuit 10 shown in FIG.
0, the high frequency signal input from the first terminal Po is divided into a second terminal Pa and a third terminal P at a power distribution ratio of 1: 1.
b, the rat race circuit 100 when the impedance of each terminal is set to 75Ω is shown in FIG.
Shown in In this case, the first distributed constant line 110 to the fourth distributed constant line 11 constituting the rat race circuit 100
3 has an impedance of about 86.603Ω. Further, the first distributed constant line 110 and the second distributed constant line 11
1, the electric phase angle θ of the third distributed constant line 112 is θ = 9
0 °, and the electrical phase angle θ of the fourth distributed constant line 113
Is set to θ = 270 °.

The return loss characteristic, the insertion loss characteristic, and the isolation characteristic of the rat race circuit 100 in the case of the parameter values shown in FIG. 21 are set to 750 MHz to 1250 MHz which is a 50% band with the center frequency being 1000 MHz. FIG. 23 shows a chart of the characteristics in the above. Referring to FIG. 23, the return loss characteristics of each terminal and the isolation characteristics between the first terminal Pa and the second terminal Pb are in the range of 875 MHz which is a 25% band.
Good characteristics are obtained at 1125 MHz. Referring to the insertion loss characteristics, at a center frequency of 1000 MHz, the insertion loss of the first terminal Pa is 3.01 dB, and the insertion loss with the second terminal Pb is 3.01 dB. And 20
In the% band, the insertion loss of the first terminal Pa is 2.
86 dB, the insertion loss of the second terminal Pb is 3.
33 dB, and the distribution loss deviation is 0.47 dB. Furthermore, in the 25% band, the insertion loss of the first terminal Pa is 2.79 dB, the insertion loss of the second terminal Pb is 3.53 dB, and the distribution loss deviation reaches 0.74 dB. This distribution loss deviation is a large distribution loss deviation that cannot be ignored.

Next, the rat race circuit 10 shown in FIG.
0, the high frequency signal input from the first terminal Po is divided into a second terminal Pa and a third terminal P at a power distribution ratio of 1: 3.
b, and the rat race circuit 100 when the impedance of each terminal is set to 75Ω is shown in FIG.
Shown in In this case, the first distributed constant line 110 and the fourth distributed constant line 11
3 is about 122.474Ω and the second
The impedance of the distributed constant line 111 and the third distributed constant line 112 is about 70.711Ω. Also, the first
The electric phase angle θ of the distributed constant line 110, the second distributed constant line 111, and the third distributed constant line 112 is θ = 90 °, and the electric phase angle θ of the fourth distributed constant line 113 is θ = 2.
70 °.

The return loss characteristic, the insertion loss characteristic, and the isolation characteristic of the rat race circuit 100 in the case of the parameter values shown in FIG. 22 are set to 750 MHz to 1250 MHz, which is a 50% band with a center frequency of 1000 MHz. FIG. 24 shows a chart of the characteristics in the above. Referring to FIG. 24, the return loss characteristics of each terminal and the isolation characteristics between the first terminal Pa and the second terminal Pb are 875 MHz or more, which is a 25% band.
Good characteristics are obtained at 1125 MHz. Referring to the insertion loss characteristics, at a center frequency of 1000 MHz, the insertion loss of the first terminal Pa is 6.02 dB, and the insertion loss with the second terminal Pb is 1.25 dB. And 20
In the% band, the insertion loss of the first terminal Pa is 5.
75 dB, the insertion loss of the second terminal Pb is 1.
45 dB, and the distribution loss deviation is 0.47 dB. Further, in the 25% band, the insertion loss of the first terminal Pa is 5.60 dB, the insertion loss of the second terminal Pb is 1.57 dB, and the distribution loss deviation reaches 0.74 dB. This distribution loss deviation is a large distribution loss deviation that cannot be ignored.

As described above, the conventional rat race circuit 10
At 0, the power distribution ratio of the high-frequency signal distributed and output from the second terminal Pa and the third terminal Pb increases as the distance from the set frequency increases, and the usable frequency band becomes narrower. There was a problem of becoming. In the rat race circuit 100, the problem that the usable frequency band is narrow even if the power distribution ratio or the impedance of each terminal is changed is not solved.
This is considered to be due to the fact that the rat race circuit 100 is not a vertically symmetric circuit.

Next, in the above-mentioned Gaicel hybrid circuit 200, the impedance at the first terminal Po, the second terminal Pa, and the third terminal Pb is used as a parameter, and the power distribution ratio is used as a parameter. The impedance, the return loss characteristic, the insertion loss characteristic, and the isolation characteristic of the first to fifth distributed constant lines 210 to 214 will be described below. A case where a high-frequency signal input from the first terminal Po is distributed to the second terminal Pa and the third terminal Pb at a power distribution ratio of 1: 1 and when the impedance of each terminal is set to 50Ω. The hybrid circuit 200 of FIG.
Shown in In this case, the Geisel hybrid circuit 20
The impedance of the first distributed constant line 210 and the second distributed constant line 211 constituting 0 is approximately 70.711Ω, and the impedance of the third distributed constant line 212 and the fourth distributed constant line 213 is 50.000Ω. , The impedance of the fifth distributed constant line 214 is about 21.20.
It is set to 0Ω. The electric phase angle θ of the first distributed constant line 210, the second distributed constant line 211, the third distributed constant line 212, and the fourth distributed constant line 213 is set to θ = 90 °,
The electric phase angle θ of the fifth distributed parameter line 214 is θ = 180
°.

The return loss characteristics, insertion loss characteristics, and isolation characteristics of the Gysel hybrid circuit 200 when the parameter values are set as shown in FIG.
FIG. 27 shows a chart of characteristics in the 0% band of 750 MHz to 1250 MHz. Referring to FIG. 27, the return loss characteristic of each terminal is 875 MHz, which is a 25% band.
Good characteristics are obtained at z to 1125 MHz.
Referring to the insertion loss characteristic, the insertion loss of the first terminal Pa and the second terminal Pb is 3.01 dB at the center frequency of 1000 MHz. In the 20% band, the insertion loss of the first terminal Pa is 3.05 dB, the insertion loss of the second terminal Pb is 3.05 dB, and the distribution loss deviation is 0 dB. Further, in the 25% band, the insertion loss at the first terminal Pa is 3.07 dB, the insertion loss at the second terminal Pb is 3.07 dB, and the distribution loss deviation is 0 dB. But the first
The isolation characteristic between the terminal Pa and the second terminal Pb is only 18.8 dB in the 875 MHz to 1125 MHz which is a 25% band, which is a sufficient amount of isolation compared to the rat race circuit 100. Not.

Next, a case is described in which the high frequency signal input from the first terminal Po is distributed to the second terminal Pa and the third terminal Pb at a power distribution ratio of 1: 3, and the impedance of each terminal is set to 50Ω. FIG. 26 shows a Geisel hybrid circuit 200 when the setting is made. In this case, the impedance of the first distributed constant line 210 configuring the Gaicel hybrid circuit 200 is set to 100.000Ω, and the impedance of the second distributed constant line 211 is approximately 57.735Ω.
And the impedance of the third distributed constant line 212 is
The impedance of the fourth distributed constant line 213 is about 70.7111Ω, and the impedance of the fifth distributed constant line 214 is about 27.700Ω. The electric phase angle θ of the first distributed constant line 210, the second distributed constant line 211, the third distributed constant line 212, and the fourth distributed constant line 213 is set to θ = 90 °. The electric phase angle θ is set to θ = 180 °.

With the parameter values shown in FIG. 26, the return loss characteristic, insertion loss characteristic, and isolation characteristic of Gaicel's hybrid circuit 200 are set to 5
FIG. 28 shows a chart of characteristics in a 0% band of 750 MHz to 1250 MHz. Referring to FIG. 28, the return loss characteristic of each terminal is 875 MHz which is a 25% band.
Good characteristics are obtained at z to 1125 MHz.
Referring to the insertion loss characteristics, at a center frequency of 1000 MHz, the insertion loss of the first terminal Pa is 60.2 dB, and the insertion loss of the second terminal Pb is 1.25 dB. And 20
In the% band, the insertion loss of the first terminal Pa is 6.
09 dB, the insertion loss of the second terminal Pb is 1.
28 dB and the distribution loss deviation is only 0.04 dB
B. Further, in the 25% band, the first terminal P
The insertion loss of a is 6.14 dB, and the second terminal P
The insertion loss of b is 1.30 dB, and the distribution loss deviation is only 0.07 dB. However, the isolation characteristic between the first terminal Pa and the second terminal Pb is 875 MHz to 1125 MHz which is a 25% band.
, Only 21.6 dB is obtained, and the isolation amount is not sufficient as compared with the rat race circuit 100.

Next, a case is described in which the high frequency signal input from the first terminal Po is distributed to the second terminal Pa and the third terminal Pb at a power distribution ratio of 1: 1. FIG. 29 shows the Geisel hybrid circuit 200 when the setting is made as follows. In this case, the impedance of the first distributed constant line 210 and the second distributed constant line 211 configuring the Gaicel hybrid circuit 200 is about 8
6.603Ω, and the impedance of the third distributed constant line 212 and the fourth distributed constant line 213 is about 61.2
37Ω, and the impedance of the fifth distributed constant line 214 is about 14.000Ω. The electric phase angle θ of the first distributed constant line 210, the second distributed constant line 211, the third distributed constant line 212, and the fourth distributed constant line 213 is θ
= 90 °, and the electric phase angle θ of the fifth distributed constant line 214 is set to θ = 180 °.

The return loss characteristics, insertion loss characteristics, and isolation characteristics of the Gysel hybrid circuit 200 when the parameter values are set as shown in FIG.
FIG. 31 shows a chart of characteristics in the 0% band of 750 MHz to 1250 MHz. Referring to FIG. 31, the return loss characteristic of each terminal is 875 MHz which is a 25% band.
Good characteristics are obtained at z to 1125 MHz.
Referring to the insertion loss characteristics, at a center frequency of 1000 MHz, the insertion loss of the first terminal Pa is 3.01 dB, and the insertion loss of the second terminal Pb is 3.01 dB. And 20
In the% band, the insertion loss of the first terminal Pa is 3.
06 dB, the insertion loss of the second terminal Pb is also 3.
06 dB, and the distribution loss deviation is 0 dB. Furthermore, in the 25% band, the insertion loss of the first terminal Pa is 3.09 dB, the insertion loss of the second terminal Pb is 3.09 dB, and the distribution loss deviation is 0 d.
B. However, the isolation characteristic between the first terminal Pa and the second terminal Pb is a 25% band 8
In the range of 75 MHz to 1125 MHz, only 15.6 dB is obtained, and the isolation amount is not sufficient as compared with the rat race circuit 100.

Next, a case is described in which the high frequency signal input from the first terminal Po is distributed to the second terminal Pa and the third terminal Pb at a power distribution ratio of 1: 3, and the impedance of each terminal is 75Ω. FIG. 30 shows the Geisel hybrid circuit 200 when the setting is made. In this case, the impedance of the first distributed constant line 210 forming the Gaisel hybrid circuit 200 is 122.474Ω, and the impedance of the second distributed constant line 211 is about 70.711Ω.
And the impedance of the third distributed constant line 212 is
50.000Ω, the impedance of the fourth distributed constant line 213 is about 86.603Ω, and the impedance of the fifth distributed constant line 214 is about 19.400Ω. Also, the first distributed constant line 210, the second distributed constant line 211, the third distributed constant line 212, the fourth distributed constant line 2
13, the electrical phase angle θ is 90 °, and the electrical phase angle θ of the fifth distributed constant line 214 is 180 °.

The return loss characteristic, the insertion loss characteristic, and the isolation characteristic of the Gaicell hybrid circuit 200 when the parameter values shown in FIG.
FIG. 32 shows a chart of characteristics in the 0% band of 750 MHz to 1250 MHz. Referring to FIG. 32, the return loss characteristic of each terminal is 875 MHz which is a 25% band.
Good characteristics are obtained at z to 1125 MHz.
Referring to the insertion loss characteristics, at a center frequency of 1000 MHz, the insertion loss of the first terminal Pa is 60.2 dB, and the insertion loss of the second terminal Pb is 1.25 dB. And 20
In the% band, the insertion loss of the first terminal Pa is 6.
08 dB, the insertion loss of the second terminal Pb is 1.
30 dB and the distribution loss deviation is only 0.01 dB
B. Further, in the 25% band, the first terminal P
The insertion loss of a is 6.12 dB, and the second terminal P
The insertion loss of b is 1.32 dB, and the distribution loss deviation is only 0.03 dB. However, the isolation characteristic between the first terminal Pa and the second terminal Pb is 875 MHz to 1125 MHz which is a 25% band.
, Only 19.1 dB is obtained, and the isolation amount is not sufficient as compared with the rat race circuit 100.

As described above, in the conventional Gaicell hybrid circuit 200, since it is a vertically symmetrical circuit, the power distribution of the high-frequency signal distributed and output from the second terminal Pa and the third terminal Pb is performed. A good distribution loss deviation is obtained even in a frequency band having a ratio of 25%. However, the conventional rat race circuit 100 has a problem that the isolation amount is not sufficient with respect to the isolation amount in a 25% frequency band. Accordingly, an object of the present invention is to provide a high-frequency hybrid circuit that can sufficiently reduce the distribution loss deviation over a wide band without deteriorating the isolation amount.

[0027]

In order to achieve the above object, a high frequency hybrid circuit according to the present invention comprises a cascaded first distributed constant line and a third distributed constant line, and a cascaded second distributed constant line. A line and a fourth distributed constant line;
A fifth distributed constant line connected between an end of the third distributed constant line and an end of the fourth distributed constant line;
A first terminal connected to a start end of the distributed constant line, a start end of the second distributed constant line, and the first distributed constant line;
A second terminal derived from a connection point with the third distributed parameter line, a third terminal derived from a connection point with the second distributed parameter line, and a fourth terminal; A connection point between the third distributed constant line and the fifth distributed constant line, a first impedance element connected between grounds,
A connection point between the distributed constant line and the fifth distributed constant line, a second impedance element connected between the ground, and a connection point between the start end of the first distributed constant line and the start end of the second distributed constant line A short stub connected to the first distributed constant line, the second distributed constant line, and the third distributed constant line.
The distributed constant line, the fourth distributed constant line, and the short stub have an electric phase angle of approximately 90 at a set frequency.
°, and the fifth fractional constant line has a length such that the electric phase angle becomes approximately 180 ° at the set frequency.

According to the present invention, the short stub is connected to the first terminal which is the connection point between the start end of the first distributed constant line and the start end of the second distributed constant line. By connecting the short stub to the first terminal in this way, a sufficient isolation amount can be ensured even in, for example, a 25% frequency band. Moreover, even if the short stub is provided, the distribution loss deviation can be maintained at a sufficiently small value in the 25% frequency band.

[0029]

FIG. 1 shows an example of a configuration of an embodiment of a high-frequency hybrid circuit according to the present invention. The high-frequency hybrid circuit 1 shown in FIG.
First distributed constant line 1 composed of a distributed constant line having a wavelength length
0, a second distributed constant line 11 composed of a distributed constant line having a length of 1/4 wavelength, a third distributed constant line 12 composed of a distributed constant line having a length of 1/4 wavelength, and a A fourth distributed constant line 13 composed of a distributed constant line having a length, and a fifth distributed constant line 14 composed of a distributed constant line having a length of 波長 wavelength
Are connected in cascade. Then, a first terminal Po is derived from a connection point between the first distributed constant line 10 and the second distributed constant line 11, and a second terminal Po is derived from a connection point between the first distributed constant line 10 and the third distributed constant line 12. A terminal Pa is derived, and a third terminal Pb is derived from a connection point between the second distributed constant line 11 and the fourth distributed constant line 13. Further, a first resistor R1 is connected to a connection point between the third distributed constant line 12 and the fifth distributed constant line 14, and a second resistor is connected to a connection point between the fourth distributed constant line 13 and the fifth distributed constant line 14. The resistor R2 is connected.

Here, the high-frequency hybrid circuit 1 according to the present invention is characterized by a first terminal Po which is a connection point between the first distributed constant line 10 and the second distributed constant line 11.
And a sixth distributed constant line 15 which is a short stub. The sixth distributed constant line 15 is composed of a distributed constant line having a length of １ ／ wavelength of the wavelength of the set frequency. The first distributed constant line 10, the second distributed constant line 11, the third distributed constant line 12, and the fourth distributed constant line 13 having a length of 1/4 wavelength in the high-frequency hybrid circuit 1 of the present invention thus configured. , Sixth distributed parameter line 1
5 and the fifth of the half wavelength length
The impedance of the distributed constant line 14 is the first terminal Pa
And the power distribution ratio at the second terminal Pb and the load impedance connected to each terminal.

In the high-frequency hybrid circuit 1 of the present invention, when a high-frequency signal is input from the first terminal Po,
For example, from the second terminal Pa and the third terminal Pb:
The high-frequency signal to which the power is distributed in 1 is output. The high frequency signal is not consumed by the first resistor R1 and the second resistor R2. This is because, at the second terminal Pa and the third terminal Pb, the high-frequency signal input from the first terminal Po and propagated through the two propagation paths arrives in phase, and the first resistor R1 And the second resistor R2
In this case, the high-frequency signal input from the first terminal Po and propagated through the two propagation paths arrives in opposite phases. Further, since the high-frequency hybrid circuit 1 of the present invention is a reversible circuit, the high-frequency signals input from the second terminal Pa and the third terminal Pb are combined and output from the first terminal Po. become.

FIG. 2 is a table comparing the electrical characteristics of the high-frequency hybrid circuit 1 of the present invention with those of the conventional rat race circuit 100 and the conventional Gaicell hybrid circuit 200. These electrical characteristics will be described with reference to FIG. FIG. 2 (a)
The drawings and numbers indicate the configuration and electrical characteristics of the conventional rat race circuit 100, the conventional Geisel hybrid circuit 200, and the high-frequency hybrid circuit 1 of the present invention in any of the drawings in this document. These configurations and electrical characteristics are based on the input impedance of the first terminal Po, the output impedance of the second terminal Pa and the third terminal Pb, and the distribution ratio.
FIG. 2B is a table comparing electrical characteristics of the conventional rat race circuit 100, the conventional Gaisel hybrid circuit 200, and the high-frequency hybrid circuit 1 of the present invention. In this comparison table, the input impedance of the first terminal Po, the second terminal Pa, and the third terminal P
The output impedance of b and the electrical characteristics in a 25% frequency band are compared for each distribution ratio.

Referring to FIG. 2B, the first terminal Po
, The output impedance of the second terminal Pa and the output impedance of the third terminal Pb are set to 50Ω, and the distribution ratio is set to 1: 1, in the conventional rat race circuit 100 in the 25% frequency band. The distribution loss deviation is set to 0.61 dB, and the conventional Geisel hybrid circuit 200 and the high-frequency hybrid circuit 1 of the present invention are used.
Is significantly degraded from the distribution loss deviation of 0 dB in the 25% frequency band. Further, when the impedance condition is the same and the distribution ratio is 1: 3, the distribution loss deviation in the conventional rat race circuit 100 in the 25% frequency band is 0.66 dB, and the conventional Gaisel hybrid is used. The distribution loss deviation in the 25% frequency band of the circuit 200 is 0.07 dB, and the distribution loss deviation in the 25% frequency band of the high frequency hybrid circuit 1 of the present invention is 0.09 dB.

Referring to the isolation characteristics when the impedance condition is the same and the distribution ratio is 1: 1, the conventional Gaisel hybrid circuit 20
The minimum amount of isolation in a frequency band of 25% of 0 is 18.8 dB, and the conventional rat race circuit 10
In addition, it is deteriorated from the minimum isolation amount of 22.4 dB in the frequency band of 25% of 0, and is significantly deteriorated from the minimum isolation amount of 24.3 dB in the 25% frequency band of the high frequency hybrid circuit 1 of the present invention. . Further, when the impedance condition is the same and the distribution ratio is 1: 3, the minimum isolation amount in the 25% frequency band of the conventional Gaicel hybrid circuit 200 is 21.6 dB, and the conventional ratchet cell is used. It degrades from the minimum isolation amount of 25.5 dB in the 25% frequency band of the race circuit 100 and significantly degrades from the minimum isolation amount of 26.7 dB in the 25% frequency band of the high-frequency hybrid circuit 1 of the present invention. ing.

Further, referring to the minimum return loss characteristic when the impedance condition is the same and the distribution ratio is 1: 1, the conventional Gaisel hybrid circuit 2
The conventional rat race circuit 100 and the high-frequency hybrid circuit 1 of the present invention have almost the same minimum return loss in a 25% frequency band. When the impedance condition is the same and the distribution ratio is 1: 3, the minimum return loss in the 25% frequency band of the conventional rat race circuit 100 is 20.8 dB, and the conventional Gaisel hybrid is used. It is slightly deteriorated from the minimum return loss of 22.4 dB in the frequency band of 25% of the circuit 200 and the high-frequency hybrid circuit 1 of the present invention.

Next, the input impedance of the first terminal Po is set to 50Ω, and the second terminal Pa and the third terminal P
b, the output impedance is 75Ω and the distribution ratio is 1: 1.
The distribution loss deviation in the 25% frequency band at 00 is 0.74 dB, which is much worse than the distribution loss deviation of 0 dB in the 25% frequency band of the conventional Gaicell hybrid circuit 200 and the high-frequency hybrid circuit 1 of the present invention. I have. Further, when the impedance conditions are the same and the distribution ratio is 1: 3, the distribution loss deviation in the 25% frequency band in the conventional rat race circuit 100 is 0.74 dB, and the conventional Gaisel hybrid is used. The distribution loss deviation is 0.03 dB in the 25% frequency band of the circuit 200 and the distribution loss deviation is 0.06 dB in the 25% frequency band of the high-frequency hybrid circuit 1 of the present invention.

Referring to the isolation characteristics when the impedance condition is the same and the distribution ratio is 1: 1, the conventional Gaisel hybrid circuit 20
The minimum amount of isolation in a frequency band of 25% of 0 is 15.6 dB.
In addition to the fact that the minimum isolation amount in a frequency band of 25% of 0 is 23.7 dB, it is much worse than the minimum isolation amount of 28.2 dB in a 25% frequency band of the high-frequency hybrid circuit 1 of the present invention. . Further, when the impedance condition is the same and the distribution ratio is 1: 3, the minimum isolation amount in the 25% frequency band of the conventional Gaicel hybrid circuit 200 is 19.1 dB, and the conventional ratchet cell is used. It degrades from the minimum isolation amount of 26.4 dB in the 25% frequency band of the race circuit 100, and deteriorates significantly from the minimum isolation amount of 30.3 dB in the 25% frequency band of the high frequency hybrid circuit 1 of the present invention. ing.

Further, referring to the minimum return loss characteristic when the impedance condition is the same and the distribution ratio is 1: 1, the conventional rat race circuit 100 has a 25% return loss.
% In a frequency band of 15.4 dB, which is lower than the minimum isolation amount 18.2 dB in the 25% frequency band of the conventional Gaisel hybrid circuit 200 and the high-frequency hybrid circuit 1 of the present invention. When the impedance condition is the same and the distribution ratio is 1: 3, the minimum isolation amount in the 25% frequency band of the conventional rat race circuit 100 is 15.9 dB, which is the same as the conventional Gaicel. The minimum isolation amount in the 25% frequency band of the hybrid circuit 200 and the high frequency hybrid circuit 1 of the present invention is 18.7 dB.

As described above, referring to FIG.
It can be seen that only the high-frequency hybrid circuit 1 of the present invention has a sufficiently small value of the distribution loss deviation in the% frequency band and a large amount of isolation in the 25% frequency band. Next, in the high-frequency hybrid circuit 1 of the present invention, the first
The impedance of the first distributed constant line 10 to the sixth distributed constant line 15 when the power distribution ratio is a parameter while the impedance of the terminal Po, the second terminal Pa, and the third terminal Pb are used as parameters, and The return loss characteristics, insertion loss characteristics, and isolation characteristics will be described below. First, a case where a high-frequency signal input from the first terminal Po is distributed to the second terminal Pa and the third terminal Pb at a power distribution ratio of 1: 1. FIG. 3 shows the high-frequency hybrid circuit 1 of the present invention when both the resistor R1 and the second resistor R2 are set to 50Ω. In this case, the first distributed constant line 1 constituting the high-frequency hybrid circuit 1 of the present invention.
The impedance of the zero and second distributed constant lines 11 is about 70.711 Ω, and the impedance of the third distributed constant line 12 and the fourth distributed constant line 13 is 50.000.
, The impedance of the fifth distributed constant line 14 is approximately 28.100Ω, and the impedance of the sixth distributed constant line 15 is approximately 69.000Ω. The first distributed constant line 10, the second distributed constant line 11, the third distributed constant line 12, the fourth distributed constant line 13, and the sixth distributed constant line 15
Is set to θ = 90 °, and the electric phase angle θ of the fifth distributed parameter line 14 is set to θ = 180 °.

The return loss characteristics, insertion loss characteristics, and isolation characteristics of the high-frequency hybrid circuit 1 of the present invention when the parameter values shown in FIG.
FIG. 5 is a table showing characteristics in the% band of 750 MHz to 1250 MHz. Referring to FIG. 5, the return loss characteristic of each terminal is 875 MHz to 1 which is a 25% band.
Good return loss characteristics of 21.7 db or more at 125 MHz are obtained. Referring to the insertion loss characteristic, the insertion loss of the first terminal Pa and the second terminal Pb is 3.01 dB at the center frequency of 1000 MHz. And 20%
In the band, the insertion loss of the first terminal Pa is 3.0.
6 dB, the insertion loss of the second terminal Pb is also 3.0.
6 dB, and the distribution loss deviation is 0 dB. Further, in the 25% band, the insertion loss of the first terminal Pa is 3.10 dB, the insertion loss of the second terminal Pb is 3.10 dB, and the distribution loss deviation is 0 d.
B and a good distribution loss deviation are obtained. Furthermore, the first
As for the isolation characteristics between the terminal Pa and the second terminal Pb, a sufficient isolation amount of 24.3 dB is obtained in the 25% band of 875 MHz to 1125 MHz.

Next, a case is described where the high frequency signal input from the first terminal Po is distributed to the second terminal Pa and the third terminal Pb at a power distribution ratio of 1: 3, and the impedance of each terminal is set to 50Ω. , The first resistor R1 and the second resistor R2 are both 5
High frequency hybrid circuit 1 of the present invention when set to 0Ω
Is shown in FIG. In this case, the impedance of the first distributed constant line 10 constituting the high-frequency hybrid circuit 1 of the present invention is 100.000Ω, and the second distributed constant line 1
1 is about 57.735Ω, and the third
The impedance of the distributed constant line 12 is about 40.825
And the impedance of the fourth distributed constant line 13 is
The impedance of the fifth distributed constant line 14 is about 31.300 Ω, and the impedance of the sixth distributed constant line 15 is about 62.000 Ω.
The first distributed constant line 10, the second distributed constant line 11,
The electric phase angle θ of the third distributed constant line 12, the fourth distributed constant line 13, and the sixth distributed constant line 15 is set to θ = 90 °,
The electric phase angle θ of the fifth distributed parameter line 14 is θ = 180 °
It has been.

The return loss characteristics, insertion loss characteristics, and isolation characteristics of the high-frequency hybrid circuit 1 according to the present invention when the parameter values are set as shown in FIG.
FIG. 6 is a table showing characteristics in the% band of 750 MHz to 1250 MHz. Referring to FIG. 6, the return loss characteristic of each terminal is 875 MHz to 1 which is a 25% band.
Good return loss characteristics of 22.4 db or more at 125 MHz are obtained. Referring to the insertion loss characteristic, the insertion loss of the first terminal Pa is 6.02 d at the center frequency of 1000 MHz.
B, the insertion loss of the second terminal Pb is 1.25d
B. In the 20% band, the first terminal P
The insertion loss of a is 6.10 dB, and the second terminal P
The insertion loss of b is 1.28 dB, and the distribution loss deviation is only 0.05 dB. Further, in the 25% band, the insertion loss at the first terminal Pa is 6.17 dB, the insertion loss at the second terminal Pb is 1.31 dB, and the distribution loss deviation is only 0.0%.
A good distribution loss deviation of 9 dB is obtained. further,
The isolation characteristic between the first terminal Pa and the second terminal Pb is 875 MHz to 1125 MHz which is a 25% band.
In z, a sufficient isolation amount of 26.7 dB is obtained.

Next, there is a case where the high-frequency signal input from the first terminal Po is distributed to the second terminal Pa and the third terminal Pb at a power distribution ratio of 1: 1. The impedance is 50Ω, the impedance of the second terminal Pa and the third terminal Pb is 75Ω, the first resistor R1, the second
FIG. 7 shows the high-frequency hybrid circuit 1 of the present invention when both the resistors R2 are set to 50Ω. In this case, the impedance of the first distributed constant line 10 and the second distributed constant line 11 constituting the high-frequency hybrid circuit 1 of the present invention is about 86.603Ω, and the third distributed constant line 12 and the fourth distributed constant line 13 has an impedance of about 6
1.237Ω, the impedance of the fifth distributed constant line 14 is about 22.200Ω, and the sixth distributed constant line 1
5 has an impedance of about 30.700Ω. The electric phase angle θ of the first distributed constant line 10, the second distributed constant line 11, the third distributed constant line 12, the fourth distributed constant line 13, and the sixth distributed constant line 15 is set to θ = 90 °, The electric phase angle θ of the fifth distributed constant line 14 is set to θ = 180 °.

The return loss characteristics, insertion loss characteristics, and isolation characteristics of the high-frequency hybrid circuit 1 of the present invention when the parameter values are set as shown in FIG.
FIG. 9 shows a chart of characteristics in the% band of 750 MHz to 1250 MHz. Referring to FIG. 9, the return loss characteristic of each terminal is 875 MHz to 1 which is a 25% band.
Good return loss characteristics of 18.2 db or more at 125 MHz are obtained. Referring to the insertion loss characteristic, the insertion loss of the first terminal Pa and the second terminal Pb is 3.01 dB at the center frequency of 1000 MHz. And 20%
In the band, the insertion loss of the first terminal Pa is 3.0.
6 dB, the insertion loss of the second terminal Pb is also 3.0.
6 dB, and the distribution loss deviation is 0 dB. Further, in the 25% band, the insertion loss of the first terminal Pa is 3.11 dB, the insertion loss of the second terminal Pb is 3.11 dB, and the distribution loss deviation is 0d.
B and a good distribution loss deviation are obtained. Furthermore, the first
As for the isolation characteristics between the terminal Pa and the second terminal Pb, a sufficient isolation amount of 28.2 dB is obtained in the 25% band of 875 MHz to 1125 MHz.

Next, there is a case where the high frequency signal input from the first terminal Po is distributed to the second terminal Pa and the third terminal Pb at a power distribution ratio of 1: 3. The impedance is 50Ω, the impedance of the second terminal Pa and the third terminal Pb is 75Ω, the first resistor R1, the second
FIG. 8 shows the high-frequency hybrid circuit 1 of the present invention when both the resistors R2 are set to 50Ω. In this case, the impedance of the first distributed constant line 10 constituting the high-frequency hybrid circuit 1 of the present invention is 122.474Ω,
The impedance of the second distributed constant line 11 is about 70.7
11Ω, the impedance of the third distributed constant line 12 is 50.000Ω, the impedance of the fourth distributed constant line 13 is approximately 86.602Ω, and the impedance of the fifth distributed constant line 14 is approximately 23.700Ω. The impedance of the sixth distributed parameter line 15 is about 30.
500Ω. In addition, the first distributed constant line 10, the second
The electric phase angle θ of the distributed constant line 11, the third distributed constant line 12, the fourth distributed constant line 13, and the sixth distributed constant line 15 is
θ = 90 °, and the electric phase angle θ of the fifth distributed parameter line 14 is set to θ = 180 °.

The return loss characteristics, insertion loss characteristics, and isolation characteristics of the high-frequency hybrid circuit 1 of the present invention when the parameter values are set as shown in FIG.
FIG. 10 shows a chart of characteristics in the% band of 750 MHz to 1250 MHz. Referring to FIG. 10, the return loss characteristic of each terminal is 875 MHz which is a 25% band.
Good return loss characteristics of 18.7 db or more are obtained at ~ 1125 MHz. Referring to the insertion loss characteristics, the insertion loss of the first terminal Pa is 6.02 at the center frequency of 1000 MHz.
dB, insertion loss of the second terminal Pb is 1.25
dB. In the 20% band, the insertion loss at the first terminal Pa is 6.09 dB, the insertion loss at the second terminal Pb is 1.29 dB, and the distribution loss deviation is only 0.03 dB. Furthermore, in the 25% band, the insertion loss of the first terminal Pa is 6.16 dB, the insertion loss of the second terminal Pb is 1.33 dB, and the distribution loss deviation is only 0.0.
A good distribution loss deviation of 6 dB is obtained. further,
The isolation characteristic between the first terminal Pa and the second terminal Pb is 875 MHz to 1125 MHz which is a 25% band.
In z, a sufficient isolation amount of 30.3 dB is obtained.

As described above, the high-frequency hybrid circuit 1 according to the present invention includes the Geisel hybrid circuit 200.
Despite being able to obtain an excellent distribution loss deviation over a wide band equivalent to the above, it is possible to obtain an isolation characteristic over a wide band superior to that of the rat race circuit 100, and further excellent over a wide band equivalent to the hybrid circuit 200 of Gaicel. Minimum return loss specification. The impedance of the fifth distributed parameter line 14 is determined by cut-and-try so as to improve the return loss characteristic (minimum reflection loss), and the impedance of the sixth distributed parameter line 15 is determined so as to improve the isolation characteristic. Determined by cut and try.
The fifth embodiment shown in FIG. 3, FIG. 4, FIG. 7 and FIG.
As the impedance value of the distributed constant line 14 and the impedance value of the sixth distributed constant line 15, an impedance value that gives the best return loss characteristics and isolation characteristics in a 25% frequency band is selected.

As described above, desired electrical characteristics can be obtained by changing the impedance value of the fifth distributed constant line 14 and the impedance value of the sixth distributed constant line 15. Thus, in the high-frequency hybrid circuit 1 of the present invention, an example of the high-frequency hybrid circuit 1 in which the impedance value of the fifth distributed constant line 14 and the impedance value of the sixth distributed constant line 15 are selected so as to obtain a return loss characteristic equivalent to that of the rat race circuit 100 is obtained. Hybrid circuit 1 shown in FIG.
FIG. 13 shows a return loss characteristic, an insertion loss characteristic, and an isolation characteristic of the high-frequency hybrid circuit 1 of the present invention in a center frequency of 1000 MHz in a 50% band of 750 MHz to 1250 MHz. Show.

The high-frequency hybrid circuit 1 of the present invention shown in FIG. 11 converts a high-frequency signal input from the first terminal Po into
This is a case where the power is distributed to the second terminal Pa and the third terminal Pb at a power distribution ratio of 1: 1.
Ω, the first resistor R1, and the second resistor R2 are both set to 50Ω. In this case, the impedance of the first distributed constant line 10 and the second distributed constant line 11 constituting the high-frequency hybrid circuit 1 of the present invention is about 70.711 Ω, and the third distributed constant line 12 and the fourth distributed constant line 1
The impedance of the third distributed constant line 15 is about 28.300 Ω, and the impedance of the sixth distributed constant line 15 is about 6
0.300Ω. Also, the first distributed constant line 10,
Electrical phase angle θ of second distributed constant line 11, third distributed constant line 12, fourth distributed constant line 13, and sixth distributed constant line 15
Is set to θ = 90 °, and the electric phase angle θ of the fifth distributed constant line 14 is set to θ = 180 °.

The electrical characteristics of the high-frequency hybrid circuit 1 according to the present invention shown in FIG. 11 are as shown in FIG.
At 125 MHz, a good return loss characteristic equivalent to the rat race circuit 100 of 21.3 db or more is obtained. Referring to the insertion loss characteristics, at a center frequency of 1000 MHz, the insertion loss of the first terminal Pa is 3.01 dB, and the insertion loss of the second terminal Pb is 3.01 dB. In the 20% band, the insertion loss of the first terminal Pa is 3.06 dB, the insertion loss of the second terminal Pb is 3.06 dB, and the distribution loss deviation is 0 dB. Furthermore, in the 25% band, the insertion loss of the first terminal Pa is 3.10 dB, the insertion loss of the second terminal Pb is 3.10 dB, and the distribution loss deviation is 0 dB, which is a good distribution loss deviation. ing. Further, the isolation characteristic between the first terminal Pa and the second terminal Pb is 875 MHz to 1125 which is a 25% band.
In MHz, the isolation amount is 25.1 dB, which is an improvement in the amount of isolation as compared with the case where the impedance value shown in FIG. As described above, when the return loss characteristics are slightly deteriorated, the isolation characteristics are improved.

Further, the high-frequency hybrid circuit 1 of the present invention
FIG. 12 shows an example of the high-frequency hybrid circuit 1 in which the impedance value of the fifth distributed constant line 14 and the impedance value of the sixth distributed constant line 15 are selected so as to obtain the same isolation characteristics as the rat race circuit 100 in FIG. The return loss characteristic, the insertion loss characteristic, and the isolation characteristic of the high-frequency hybrid circuit 1 of the present invention are set assuming that the center frequency is 1000 MHz.
FIG. 14 shows a chart of the characteristics in the 50% band of 750 MHz to 1250 MHz.

The high-frequency hybrid circuit 1 of the present invention shown in FIG. 12 converts a high-frequency signal input from the first terminal Po into
This is a case where the power is distributed to the second terminal Pa and the third terminal Pb at a power distribution ratio of 1: 1.
Ω, the first resistor R1, and the second resistor R2 are both set to 50Ω. In this case, the impedance of the first distributed constant line 10 and the second distributed constant line 11 constituting the high-frequency hybrid circuit 1 of the present invention is about 70.711 Ω, and the third distributed constant line 12 and the fourth distributed constant line 1
3, the impedance of the fifth distributed parameter line 14 is about 26.700 Ω, and the impedance of the sixth distributed parameter line 15 is about 10
8.000Ω. Also, the first distributed constant line 10,
Electrical phase angle θ of second distributed constant line 11, third distributed constant line 12, fourth distributed constant line 13, and sixth distributed constant line 15
Is set to θ = 90 °, and the electric phase angle θ of the fifth distributed constant line 14 is set to θ = 180 °.

The electrical characteristics of the high-frequency hybrid circuit 1 of the present invention shown in FIG. 12 are as follows: As shown in FIG. 14, the isolation characteristic between the first terminal Pa and the second terminal Pb is 2
In the 5% band of 875 MHz to 1125 MHz, the isolation amount is 22.4 dB, which is as good as the rat race circuit 100. Also, referring to the insertion loss characteristics, the center frequency is 1000 MHz.
At z, the insertion loss at the first terminal Pa is 3.01 dB, and the insertion loss at the second terminal Pb is 3.01 dB. In the 20% band, the insertion loss of the first terminal Pa is 3.05 dB, the insertion loss of the second terminal Pb is 3.05 dB, and the distribution loss deviation is 0 dB. In the 25% band, the insertion loss of the first terminal Pa is 3.09.
dB, the insertion loss of the second terminal Pb is also 3.09.
dB, and a good distribution loss deviation of 0 dB was obtained. Further, the return loss characteristic of each terminal in the 875 MHz to 1125 MHz, which is a 25% band, is more improved than the case where the impedance value is 22.3 db or more as shown in FIG. 3. As described above, when the isolation characteristics are slightly deteriorated, the return loss characteristics are improved.

The first distributed constant line 10 and the second distributed constant line 1 in the above-described high-frequency hybrid circuit 1 of the present invention.
Although the electric phase angle θ of the first, third, and fourth distributed constant lines 12, 13, and 15 is 90 °, and the electric phase angle θ of the fifth distributed constant line 14 is 180 °, it is strict. In addition, it is difficult to form a distributed constant line at 90 ° or 180 °, and the above-described good electric characteristics can be obtained even if the electric phase angle is slightly deviated from 90 ° or 180 °. Thus, in the high-frequency hybrid circuit 1 of the present invention, the first distributed constant line 10,
Electrical phase angle θ of second distributed constant line 11, third distributed constant line 12, fourth distributed constant line 13, and sixth distributed constant line 15
May be about 90 °, and the electric phase angle θ of the fifth distributed constant line 14 may be about 180 °. 3 and 4
The same applies to the impedance value of the fifth distributed constant line 14 and the impedance value of the sixth distributed constant line 15 shown in FIGS. 7 and 8, and it is not necessary to strictly set the impedance values.

[0055]

As described above, according to the present invention, the short stub is connected to the first terminal which is the connection point between the beginning of the first distributed constant line and the beginning of the second distributed constant line. By connecting the short stub to the first terminal in this way, a sufficient isolation amount can be ensured even in, for example, a 25% frequency band. Moreover, even if the short stub is provided, the distribution loss deviation can be maintained at a sufficiently small value in the 25% frequency band.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an embodiment of a high-frequency hybrid circuit of the present invention.

FIG. 2 is a table comparing electrical characteristics of a high-frequency hybrid circuit of the present invention with electrical characteristics of a conventional rat race circuit and a conventional Gaicell hybrid circuit.

FIG. 3 shows a first example of the high-frequency hybrid circuit of the present invention.
FIG. 4 is a diagram showing a configuration in the case of using the parameters of FIG.

FIG. 4 shows a second example of the high-frequency hybrid circuit of the present invention.
FIG. 4 is a diagram showing a configuration in the case of using the parameters of FIG.

FIG. 5 shows a first high-frequency hybrid circuit of the present invention.
4 is a table showing electric characteristics when the parameters are set as follows.

FIG. 6 shows a second example of the high-frequency hybrid circuit of the present invention.
4 is a table showing electric characteristics when the parameters are set as follows.

FIG. 7 shows a third embodiment of the high-frequency hybrid circuit according to the present invention.
FIG. 4 is a diagram showing a configuration in the case of using the parameters of FIG.

FIG. 8 shows a fourth embodiment of the high-frequency hybrid circuit according to the present invention.
FIG. 4 is a diagram showing a configuration in the case of using the parameters of FIG.

FIG. 9 shows a third example of the high-frequency hybrid circuit of the present invention.
4 is a table showing electric characteristics when the parameters are set as follows.

FIG. 10 is a table showing electric characteristics when a fourth parameter is set in the high-frequency hybrid circuit of the present invention.

FIG. 11 is a diagram showing a configuration when a fifth parameter is set in the high-frequency hybrid circuit of the present invention.

FIG. 12 is a diagram showing a configuration when a sixth parameter is used in the high-frequency hybrid circuit of the present invention.

FIG. 13 is a table showing electric characteristics when a fifth parameter is set in the high-frequency hybrid circuit of the present invention.

FIG. 14 is a table showing electric characteristics when a sixth parameter is set in the high-frequency hybrid circuit of the present invention.

FIG. 15 is a diagram showing a configuration of a conventional rat race circuit.

FIG. 16 is a diagram showing a configuration of a conventional Gaicell hybrid circuit.

FIG. 17 is a diagram showing a configuration when a first parameter is used in a conventional rat race circuit.

FIG. 18 is a diagram showing a configuration when a second parameter is used in a conventional rat race circuit.

FIG. 19 is a table showing electric characteristics when a first parameter is used in a conventional rat race circuit.

FIG. 20 is a table showing electric characteristics when a second parameter is used in a conventional rat race circuit.

FIG. 21 is a diagram illustrating a configuration when a third parameter is used in a conventional rat race circuit.

FIG. 22 is a diagram showing a configuration when a fourth parameter is used in a conventional rat race circuit.

FIG. 23 is a table showing electric characteristics when a third parameter is used in a conventional rat race circuit.

FIG. 24 is a table showing electric characteristics when a fourth parameter is set in a conventional rat race circuit.

FIG. 25 is a diagram showing a configuration when a first parameter is used in a conventional Gaicell hybrid circuit.

FIG. 26 is a diagram showing a configuration when a second parameter is used in a conventional Gaicell hybrid circuit.

FIG. 27 is a table showing electric characteristics when a first parameter is used in a conventional Gaicell hybrid circuit.

FIG. 28 is a table showing electrical characteristics when a second parameter is used in a conventional Geisel hybrid circuit.

FIG. 29 is a diagram showing a configuration when a third parameter is used in a conventional Gaicell hybrid circuit.

FIG. 30 is a diagram showing a configuration when a fourth parameter is used in a conventional Gaicell hybrid circuit.

FIG. 31 is a table showing electrical characteristics when a third parameter is used in a conventional Gaicel hybrid circuit.

FIG. 32 is a table showing electric characteristics when a fourth parameter is used in a conventional Gaicel hybrid circuit.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 High frequency hybrid circuit, 10 1st distributed constant line, 11 2nd distributed constant line, 12 3rd distributed constant line, 13 4th distributed constant line, 14 5th distributed constant line, 15 6th distributed constant line, 100 rat race Circuit, 110 first distributed constant line, 111 second distributed constant line, 112 third distributed constant line, 113 fourth distributed constant line, 200 hybrid circuit, 210 first distributed constant line, 211 second distributed constant line, 212 3 distributed constant line, 213 fourth distributed constant line, 214 fifth distributed constant line, Pa second terminal, Pb third terminal, P
o 1st terminal, R resistance, R1 1st resistance, R2
Second resistance

Claims (1)

[Claims] A cascaded first distributed constant line and a third distributed constant line; a cascaded second distributed constant line and a fourth distributed constant line; an end of the third distributed constant line; A fifth terminal connected to an end of the fourth distributed constant line, a first terminal connected to a start of the first distributed constant line, and a start of the second distributed constant line; A second terminal derived from a connection point between the first distributed constant line and the third distributed constant line; and a second terminal derived from a connection point between the second distributed constant line and the fourth distributed constant line. A third terminal, a connection point between the third distributed constant line and the fifth distributed constant line, a first impedance element connected between the ground, a fourth distributed constant line and the fifth distributed constant line A second impedance connected between the line connection point and ground A short stub connected to a connection point between a start end of the first distributed constant line and a start end of the second distributed constant line, wherein the first distributed constant line, the second distributed constant line, The third distributed constant line, the fourth distributed constant line, and the short stub have a length at which an electric phase angle is substantially 90 ° at a set frequency, and the fifth distributed constant line has a setting. 180 ° electrical phase angle at frequency
A high frequency hybrid circuit characterized in that the length is such that: