JPH11308026A - Rat race hybrid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a rat race hybrid to be easily laid out and with superior isolation between input and output by making each of fifth and fourth transmission lines crossed by spatially avoiding each other, at a point where electric length from a junction of first, fourth and eighth transmission lines is prescribed on the fourth transmission line. SOLUTION: An input terminal and an output terminal are separated and layout of a high frequency circuit is facilitated by making the fifth transmission line 5 crossed with the fourth transmission line 4. Signals inputted from a terminal 11 do not leak to a terminal 12, even if a part of them leaks to the fourth transmission line 4 at the junction of the fifth transmission line 5 and the fourth transmission line 4, since the difference in the electric length of two routes from the junction to the terminal 12 is 180 deg.. Conversely, signals inputted in the terminal 12 are compensated each other at the intersection and will not leak to the fifth transmission line 5, since the difference of the electric length of two routes from the terminal 12 to the intersection is 180 deg.. Therefore, the terminal 11 and the terminal 12 are isolated from each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a rat race hybrid used for a high frequency circuit.

[0002]

[Prior Art 1] A rat race hybrid is a circuit for performing phase difference power distribution or power synthesis including the same phase in a high-frequency circuit, and is used as a component such as a balanced mixer. FIG. 7 shows a conventional rat race hybrid. Rat Race Hybrid
Characteristic impedance 2 ^0.5 × Zo, the first transmission line 71 of electrical length 90 °, one of the characteristics one terminal of which is connected to the terminal impedance of the first transmission line 71 2 ^0.5 × Z
o, a second transmission line 72 of electrical length 90 °, a second transmission line other one terminal connected characteristic impedance 2 ^0.5 × Zo to the terminal 72, the third transmission line of electrical length 90 ° One terminal is connected to the other terminal of the third transmission line 73, and the first transmission line 7 is connected to the other terminal.
Characteristic impedance 2 ^0.5 × Z to which 1 terminal is connected
o, a fourth transmission line 74 having an electrical length of 270 °, a fifth transmission line 75 having a characteristic impedance Zo and one terminal connected to a connection point between the first transmission line 71 and the second transmission line 72. , A characteristic impedance Zo having one terminal connected to a connection point between the second transmission line 72 and the third transmission line 73.
A sixth transmission line 76, a seventh transmission line 77 having a characteristic impedance Zo having one terminal connected to a connection point of the third transmission line 73 and the fourth transmission line 74, and a fourth transmission line An eighth transmission line 7 having a characteristic impedance Zo and one terminal connected to a connection point between the first transmission line 74 and the first transmission line 71.
Consists of eight. The other terminals of the fifth transmission line, the sixth transmission line, the seventh transmission line, and the eighth transmission line are referred to as a terminal 11, a terminal 13, a terminal 12, and a terminal 14, respectively.

Next, the operation of the rat race hybrid will be described. The signal input to the terminal 11 is distributed to the terminals 13 and 14 and output. Terminal 11 to Terminal 1
3 and the path from the terminal 11 to the terminal 14 have the same electrical length, so that the signal output to the terminal 13 and the terminal 14
Are equal in phase. Also, the two paths from the terminal 11 to the terminal 12 have a difference of 180 ° in electrical length, and the signals input to the terminal 11 cancel each other out at the terminal 12 and are not output to the terminal 12.

On the other hand, the signal input to the terminal 12 is distributed to the terminals 13 and 14 and output. Terminal 12
Since the path from the terminal 13 to the terminal 13 is shorter than the path from the terminal 12 to the terminal 14 by an electrical length of 180 °, the signal output to the terminal 13 and the signal output to the terminal 14 have a phase difference of one.
80 °. Further, the two paths from the terminal 12 to the terminal 13 have a difference of an electrical length of 180 °, and the signals input to the terminal 12 cancel each other out at the terminal 11 and are not output to the terminal 12.

However, the conventional rat race hybrid has the following problems. First, in the case of [Prior Art 1], since input terminals and output terminals are alternately arranged, it is necessary to route the lines when laying out a high-frequency circuit such as a balanced mixer or a multiplier, and the layout becomes complicated. However, there is a problem that the occupied area increases. Therefore, the following rat race hybrid has been considered as a prior art 2 that solves these problems.

[Prior Art 2] FIG. 8 shows a rat race hybrid of Prior Art 2. As in the prior art 1, the rat race hybrid has a characteristic impedance of ^20.5 × Z
o, a first transmission line 81 of electrical length 90 °, one of the one terminal connected characteristic impedance 2 ^0.5 × Zo to a terminal of the first transmission line, the electrical length 90 ° the second transmission line 82 When, a second transmission line other one terminal connected characteristic impedance 2 ^{0. 5} × Zo to the terminal, the third transmission line having an electrical length 90 ° 83 82 of the other of the third transmission line 83 one terminal connected to the terminal, the other of the first terminal of the transmission line 81 is connected characteristic impedance 2 ^0.5 × Zo to the terminal, an electrical length 270 ° of the fourth transmission line 8
4, a fifth transmission line 85 having a characteristic impedance Zo whose one terminal is connected to a connection point between the first transmission line 81 and the second transmission line 82, a second transmission line 82 and a third transmission line A sixth transmission line 86 of characteristic impedance Zo in which one terminal is connected to a connection point of the line 83, and a characteristic in which one terminal is connected to a connection point of the third transmission line 83 and the fourth transmission line 84. Seventh transmission line 87 with impedance Zo
And an eighth transmission line 88 having a characteristic impedance Zo of which one terminal is connected to a connection point between the fourth transmission line 84 and the first transmission line 81. The fifth transmission line 85 and the fourth transmission line The line 84 crosses one transmission line while spatially avoiding the other transmission line. The other terminals of the fifth transmission line, the sixth transmission line, the seventh transmission line, and the eighth transmission line are referred to as terminals 11, 13, and 1, respectively.
2, terminal 14.

Next, the operation of the rat race hybrid will be described. The signal input to the terminal 11 is distributed to the terminals 13 and 14 and output. Since the path from the terminal 11 to the terminal 13 and the path from the terminal 11 to the terminal 14 have the same electrical length, the signal output to the terminal 13 and the terminal 1
4 have the same phase. Also, the two paths from the terminal 11 to the terminal 12 have a difference of 180 ° in electrical length, and the signals input to the terminal 11 cancel each other out at the terminal 12 and are not output to the terminal 12.

On the other hand, the signal input to the terminal 12 is distributed to the terminals 13 and 14 and output. Terminal 12
Since the path from the terminal 13 to the terminal 13 is shorter than the path from the terminal 12 to the terminal 14 by an electrical length of 180 °, the signal output to the terminal 13 and the signal output to the terminal 14 have a phase difference of one.
80 °. Further, the two paths from the terminal 12 to the terminal 13 have a difference of an electrical length of 180 °, and the signals input to the terminal 12 cancel each other out at the terminal 11 and are not output to the terminal 12.

Further, by crossing the fifth transmission line 85 with the fourth transmission line 84, the terminal 11 and the terminal
Are arranged and the terminals 13 and the terminals 14 are arranged side by side, so that the input terminal and the output terminal can be separated, and the layout of the high-frequency circuit becomes easy.

[0010]

However, also in the case of the rat race hybrid shown in the prior art 2, it is necessary to partially cross the two transmission lines, and one of the transmission lines is placed on the other transmission line in space. Even if the intersection is avoided, the capacitance component generated between the lines at the intersection causes
As the frequency increases, the signal passing through one line leaks into the other line. For this reason, there is a problem that a part of the signal input to one input terminal leaks from the other input terminal, and the isolation between the two input terminals deteriorates. In particular, in a millimeter wave band having a frequency of several tens of GHz, leakage at an intersection becomes remarkable.

In particular, an MMIC (Monoli) in which active elements such as transistors and passive elements such as capacitors, inductors, resistors, and transmission lines are integrated on the same semiconductor substrate.
thic Microwave Integrated
(Circuit), it is required to reduce the chip area, and the signal leakage when the transmission lines are crossed is remarkable. This is a particularly serious problem when integrating race hybrids.

The present invention has been made in order to solve these problems, and an object of the present invention is to provide a rat race hybrid having an easy layout and excellent input-output isolation. .

[0013]

Means for Solving the Problems] rat race hybrid according to the invention of claim 1, the characteristic impedance 2 ^0.5 × Zo, a first transmission line of electrical length 90 °, one of the first transmission line one terminal of which is connected characteristic impedance 2 ^0.5 × Zo terminal, a second transmission line of electrical length 90 °, a second transmission line other one terminal connected characteristic impedance 2 ^0.5 × the terminal of Zo, electrical length 9
A characteristic impedance 2 ^0.5 × Z in which one terminal is connected to the third transmission line of 0 ° and the other terminal of the third transmission line, and the other terminal is connected to the terminal of the first transmission line.
o, a fourth transmission line having an electrical length of 270 °, a fifth transmission line having a characteristic impedance Zo having one terminal connected to a connection point between the first transmission line and the second transmission line, One terminal is connected to a connection point between the third transmission line and the fourth transmission line, and a sixth transmission line having a characteristic impedance Zo in which one terminal is connected to a connection point between the transmission line and the third transmission line. A seventh transmission line having a characteristic impedance Zo,
An eighth transmission line having a characteristic impedance Zo having one terminal connected to a connection point between the fourth transmission line and the first transmission line, and the first transmission line and the fourth transmission line on the fourth transmission line. The electrical length is 90 ° from the connection point of the transmission line and the eighth transmission line.
At the point of, the fifth transmission line and the fourth transmission line intersect spatially avoiding each other.

According to a second aspect of the present invention, in the rat race hybrid, the first, second, third, fourth, fifth, sixth, seventh, and eighth transmission lines are formed on a substrate. The fifth transmission line and the fourth transmission line intersect with each other, with one of the transmission lines spatially avoiding the other transmission line.

According to a third aspect of the present invention, in the rat race hybrid, the first, second, third, fourth, fifth, sixth, seventh, and eighth transmission lines are formed on a substrate. The fifth transmission line and the fourth transmission line intersect with each other while one of the transmission lines spatially avoids the other transmission line.

[0016]

[First Embodiment] FIG. 1 shows a rat race hybrid of the present invention. Rat Race hybrid characteristic impedance 2 ^0.5 × Zo, the electrical length 9
A first transmission line 1 at 0 ° and a characteristic impedance 2 ^0.5 having one terminal connected to one terminal of the first transmission line.
× Zo, a second transmission line 2 having an electric length of 90 °, and a third transmission line having a characteristic impedance of 2 ^0.5 × Zo and an electric length of 90 °, one terminal of which is connected to the other terminal of the second transmission line 2. One terminal is connected to the line 3 and the other terminal of the third transmission line 3, and the other terminal is connected to the terminal of the first transmission line 1. Characteristic impedance 2 ^0.5 × Zo, electrical length 270 °, a fifth transmission line 5 having a characteristic impedance Zo having one terminal connected to a connection point between the first transmission line 1 and the second transmission line 2, and a second transmission line A sixth transmission line 6 having a characteristic impedance Zo and one terminal connected to a connection point between the line 2 and the third transmission line 3
A seventh transmission line 7 having a characteristic impedance Zo having one terminal connected to a connection point between the third transmission line 3 and the fourth transmission line 4, a fourth transmission line 4, and a first transmission line. Characteristic impedance Z with one terminal connected to the connection point 1
o, including an eighth transmission line 8 on the fourth transmission line 4,
At a point where the electrical length is 90 ° from the connection point of the first transmission line 1, the fourth transmission line 4, and the eighth transmission line 8, the fifth transmission line 5 and the fourth transmission line 4 are spatially separated. Avoid and cross. As a method of spatially avoiding and crossing the fifth transmission line 5 and the fourth transmission line 4, a commonly used air bridge, ribbon wire, or the like is used.

Next, the operation of the rat race hybrid will be described. The signal input to the terminal 11 is distributed to the terminals 13 and 14 and output. Terminal 11 to Terminal 1
3 and the path from the terminal 11 to the terminal 14 have the same electrical length, so that the signal output to the terminal 13 and the terminal 14
Are equal in phase. Also, the two paths from the terminal 11 to the terminal 12 have a difference of 180 ° in electrical length, and the signals input to the terminal 11 cancel each other out at the terminal 12 and are not output to the terminal 12.

On the other hand, the signal input to the terminal 12 is distributed to the terminals 13 and 14 and output. Terminal 12
Since the path from the terminal 13 to the terminal 13 is shorter than the path from the terminal 12 to the terminal 14 by an electrical length of 180 °, the signal output to the terminal 13 and the signal output to the terminal 14 have a phase difference of one.
80 °. Further, the two paths from the terminal 12 to the terminal 13 have a difference of an electrical length of 180 °, and the signals input to the terminal 12 cancel each other out at the terminal 11 and are not output to the terminal 12.

Further, by intersecting the fifth transmission line 5 with the fourth transmission line 4, the terminals 11 and 12 are arranged and the terminals 13 and 14 are arranged, so that the input terminal and the output terminal can be separated. The layout of the high-frequency circuit becomes easy.

Further, even if a signal input from the terminal 11 partially leaks to the fourth transmission line 4 at the intersection of the fifth transmission line 5 and the fourth transmission line 4, even if the fifth transmission line 5 and the fourth transmission line 4 Since the difference between the electrical lengths of the two paths from the intersection of the four transmission lines 4 to the terminal 12 is 180 °, no leakage occurs to the terminal 12.

Conversely, the signal input to terminal 12 is
Since the difference between the electrical lengths of the two paths from the second to the fifth transmission line 5 and the intersection of the fourth transmission line 4 is 180 °, the intersection of the fifth transmission line 5 and the fourth transmission line 4 is obtained. Then, they cancel each other and do not leak to the fifth transmission line 5. Therefore, the terminals 11 and 12 can be isolated from each other.

Second Embodiment FIG. 2 shows a rat race hybrid 100 using a microstrip line as a signal line as a second embodiment. Rat Race hybrid characteristic impedance 2 ^0.5 × Zo, electrical length 90
A first microstrip line 21 °, one of the one terminal connected characteristic impedance 2 ^0.5 × Zo to a terminal of the first microstrip line 21, the electrical length 90
A second microstrip line 22 °, the second of the other one terminal connected characteristic impedance 2 ^0.5 × Zo to the terminals of the microstrip line 22, the electrical length 90
And a characteristic impedance 2 in which one terminal is connected to the other terminal of the third microstrip line 23 and the other terminal of the third microstrip line 23 and the terminal of the first transmission line 21 is connected to the other terminal. ^0.5 x Zo, electrical length 2
A fourth microstrip line 24 of 70 °, and a fifth microstrip line 25 of characteristic impedance Zo having one terminal connected to a connection point between the first microstrip line 21 and the second microstrip line 22
A sixth microstrip line 26 having a characteristic impedance Zo having one terminal connected to a connection point between the second microstrip line 22 and the third microstrip line 23; a third microstrip line 23; A seventh microstrip line 27 having a characteristic impedance Zo having one terminal connected to a connection point of the four microstrip lines 24, and a fourth microstrip line 2
4 includes an eighth microstrip line 28 having a characteristic impedance Zo having one terminal connected to a connection point between the first microstrip line 21 and the first microstrip line 21. 2
At a point where the electrical length is 90 ° from the connection point of the first, fourth microstrip line 24 and eighth microstrip line 28, the fifth microstrip line 25 and fourth microstrip line 24 are spatially avoided. And cross.

Next, the operation of the rat race hybrid will be described. The signal input to the terminal 11 is distributed to the terminals 13 and 14 and output. Terminal 11 to Terminal 1
3 and the path from the terminal 11 to the terminal 14 have the same electrical length, so that the signal output to the terminal 13 and the terminal 14
Are equal in phase. Also, the two paths from the terminal 11 to the terminal 12 have a difference of 180 ° in electrical length, and the signals input to the terminal 11 cancel each other out at the terminal 12 and are not output to the terminal 12.

On the other hand, the signal input to the terminal 12 is distributed to the terminals 13 and 14 and output. Terminal 12
Since the path from the terminal 13 to the terminal 13 is shorter than the path from the terminal 12 to the terminal 14 by an electrical length of 180 °, the signal output to the terminal 13 and the signal output to the terminal 14 have a phase difference of one.
80 °. Further, the two paths from the terminal 12 to the terminal 13 have a difference of an electrical length of 180 °, and the signals input to the terminal 12 cancel each other out at the terminal 11 and are not output to the terminal 12.

The fifth microstrip line 25
Are crossed with the fourth microstrip line 24 so that the terminals 11 and 12 are aligned, and the terminals 13 and 1
Since four are arranged, the input terminal and the output terminal can be separated, and the layout of the high-frequency circuit becomes easy.

Further, even if the signal input from the terminal 11 partially leaks to the fourth microstrip line 24 at the intersection of the fifth microstrip line 25 and the fourth microstrip line 24, The difference between the electrical lengths of the two paths from the intersection of the line 25 and the fourth microstrip line 24 to the terminal 12 is 180
°, it does not leak to the terminal 12.

On the contrary, the signal input to the terminal 12 is
Since the difference between the electrical lengths of the two paths from the second to the fifth microstrip line 25 and the intersection of the fourth microstrip line 24 is 180 °, the fifth microstrip line 25 and the fourth microstrip line 25 At the intersection of the lines 24, they cancel each other out and do not leak to the fifth microstrip line 25. Therefore, the terminals 11 and 12 can be isolated from each other.

FIGS. 3A and 3B show a top view and a sectional view of the microstrip line, respectively. The microstrip line includes a signal line 31, a ground conductor 32, and a substrate 33. The characteristic impedance of the microstrip line is determined by the dielectric constant of the substrate 33 and the ratio of the thickness h of the substrate 33 and the width w of the signal line 31.

Third Embodiment FIG. 4 shows a rat race hybrid 110 using a coplanar line as a signal line as a third embodiment. Rat Race Hybrid
Characteristic impedance 2 ^0.5 × Zo, the first coplanar line 41 of electrical length 90 °, one of the one terminal connected characteristic impedance 2 ^0.5 × Zo to a terminal of the first coplanar line 41, the electrical length 90 ° second coplanar line 42, the second of the other is one terminal connected characteristic impedance 2 ^0.5 × Zo to the terminals of the coplanar line 42,
A third coplanar line 43 having an electrical length of 90 °, and one terminal connected to the other terminal of the third coplanar line 43;
The other terminal first transmission line 41 terminal connected characteristic impedance 2 ^0.5 × Zo of electrical length 270 °
A fourth coplanar line 44, a fifth coplanar line 45 having a characteristic impedance Zo having one terminal connected to a connection point between the first coplanar line 41 and the second coplanar line 42, and a second coplanar line A sixth coplanar line 46 having a characteristic impedance Zo in which one terminal is connected to a connection point of the second coplanar line 43 and the fourth coplanar line 43. Characteristic impedance Z to which the terminal is connected
a seventh coplanar line 47 having a characteristic impedance Zo having one terminal connected to a connection point of the fourth coplanar line 44 and the first coplanar line 41, and a fourth coplanar line 48 having a characteristic impedance Zo. On coplanar track 44,
First coplanar line 41 and fourth coplanar line 44
The electrical length is 90 from the connection point of the
At the point of °, the fifth coplanar line 45 and the fourth coplanar line 44 intersect. Air bridge 49
Is for equalizing the potential of the inner ground conductor and the outer ground conductor of the rat race hybrid, and is generally used in a coplanar line.

Next, the operation of the rat race hybrid will be described. The signal input to the terminal 11 is distributed to the terminals 13 and 14 and output. Terminal 11 to Terminal 1
3 and the path from the terminal 11 to the terminal 14 have the same electrical length, so that the signal output to the terminal 13 and the terminal 14
Are equal in phase. Also, the two paths from the terminal 11 to the terminal 12 have a difference of 180 ° in electrical length, and the signals input to the terminal 11 cancel each other out at the terminal 12 and are not output to the terminal 12.

On the other hand, the signal input to the terminal 12 is distributed to the terminals 13 and 14 and output. Terminal 12
Since the path from the terminal 13 to the terminal 13 is shorter than the path from the terminal 12 to the terminal 14 by an electrical length of 180 °, the signal output to the terminal 13 and the signal output to the terminal 14 have a phase difference of one.
80 °. Further, the two paths from the terminal 12 to the terminal 13 have a difference of an electrical length of 180 °, and the signals input to the terminal 12 cancel each other out at the terminal 11 and are not output to the terminal 12.

The fifth coplanar line 45 intersects the fourth coplanar line 44 so that the terminal 11
And the terminal 12 are arranged, and the terminal 13 and the terminal 14 are arranged. Therefore, the input terminal and the output terminal can be separated, and the layout of the high-frequency circuit becomes easy.

Further, even if the signal input from the terminal 11 partially leaks to the fourth coplanar line 44 at the intersection of the fifth coplanar line 45 and the fourth coplanar line 44, the fifth coplanar line 45 and the fourth Since the difference between the electrical lengths of the two paths from the intersection of the four coplanar lines 44 to the terminal 12 is 180 °, no leakage occurs to the terminal 12.

On the contrary, the signal input to the terminal 12 is
The difference between the electrical lengths of the two routes from the second to the fifth coplanar line 45 and the intersection of the fourth coplanar line 44 is 180.
°, the crossings cancel each other at the intersection of the fifth coplanar line 45 and the fourth coplanar line 44 and do not leak to the fifth coplanar line 45. Therefore, the terminals 11 and 12 can be isolated from each other.

FIGS. 5A and 5B are a top view and a cross-sectional view of the coplanar line, respectively. The coplanar line includes the signal line 51, the ground conductors 50a and 50b, and the substrate 5
It consists of two. The characteristic impedance of the coplanar line is determined by the dielectric constant of the substrate 52, the width W of the signal line 51, and the ratio of the distance S between the signal line 51 and the ground conductors 50a and 50b. Since the potential of the ground conductors on both sides of the coplanar line is different depending on the layout, particularly at discontinuous portions, the potentials of the ground conductors on both sides are often equalized using the air bridge 49.

Embodiment 4 FIG. 6 shows an example of a down converter as an example of integration of the rat race hybrid of the present invention and an amplifier or a frequency converter.

The down converter includes the rat race hybrid 120 of the present invention, the capacitors 60a, 60b, 6
1a, 61b, 61c, 61d, matching circuits 62a, 62
b, and transistors 63a, 63b, reflector 64
a, 64b, via holes 65a, 65b, 65c, 6
5d, 66a, 66b, 66c and 66d. Each terminal of the rat race hybrid 120 is the same as that of the second embodiment.
And the respective terminals of the rat race hybrid 100 described above. The capacitors 60a and 60b have a function of blocking a DC bias and allowing a high-frequency signal to pass. The capacitors 61a, 61b, 61c, and 61d function to ground at high frequencies. The matching circuits 62a and 62b are constituted by transmission lines and have a function of inputting the input signal to the transistors 63a and 63b without reflecting the input signal.

The reflectors 64a and 64b are also constituted by transmission lines, and have a function of reflecting the input signal leaked to the output side of the transistors 63a and 63b to the transistors 63a and 63b. Various transistors can be considered as the transistor, such as a field effect transistor, a bipolar transistor, and a heterojunction bipolar transistor. The transistor is turned on by applying a DC bias from terminals 15, 16, 17, and 18. Via holes 65a, 65b, 65c, 65d, 66a, 66b,
66c and 66d are connected to the ground conductor on the back surface of the substrate to provide a ground surface on the surface of the substrate, and are generally used in a circuit using a microstrip line.

The operation of the down converter will be described. Each frequency terminals 11 and the terminal 12 for inputting an input signal of the input signal and f ₂ of f _1. The frequency of the terminal 11 in accordance with the input signal operating principle of the rat race hybrid f _1, is distributed in phase to the terminal 13 and the terminal 14. On the other hand, the input signal 2 frequency f ₂ from terminal 12 according to the operation principle of the rat-race hybrid is distributed in opposite phase to the terminal 13 and the terminal 14. The divided input signals are input to the transistor 63 through the matching circuit. The two signals input to the transistors 63a and 63b are mixed due to the non-linearity of the transistors, and a signal having a frequency difference | f ₁ −f ₂ | between the _two signals is output. This signal is applied to DC bias terminals 17 and 18
Taken out of Moreover, the reflectors 64a, the input signals and terminals 12 of frequency f ₁ from the terminal 11 by 64b
The input signal having the frequency f ₂ from the transistor 63a is
Since it is returned to 63b, the non-linearity of the transistor becomes stronger, and the efficiency of frequency conversion is increased. Terminal 17,
Since the two output signals output to 18 have opposite phases, they are in-phase synthesized using components such as a balun. Usually, one of the input signals 1 and 2 is a modulation signal, the other is a local oscillation signal, and the output signal is an intermediate frequency signal.

The rat race hybrid 120 is shown in FIG.
The structure is the same as that of the rat race hybrid 100 already shown in FIG. Therefore, as already described with reference to FIG. 2, by crossing the fifth transmission line 25 with the fourth transmission line 24, the terminals 11 and 12 are arranged and the terminals 13 and 14 are arranged. And the output terminal can be separated, and the layout becomes easy.

Further, even if the signal input from the terminal 11 partially leaks to the fourth transmission line 24 at the intersection of the fifth transmission line 25 and the fourth transmission line 24, even if the fifth transmission line 25 and the fourth Since the difference between the electrical lengths of the two paths from the intersection of the four transmission lines 24 to the terminal 12 is 180 °, the terminal 1
2 does not leak.

On the contrary, the signal input to the terminal 12 is
Since the difference between the electrical lengths of the two paths from the second to the fifth transmission line 25 and the intersection of the fourth transmission line 24 is 180 °, the intersection of the fifth transmission line 25 and the fourth transmission line 24 is obtained. Then, they cancel each other out and do not leak to the fifth transmission line 25. Therefore, the terminals 11 and 12 can be isolated from each other.

In the rat race 120, the terminals 11 and 12 can be isolated from each other.
Input signal 2 frequency f ₂ from the input signal 1 and the terminal 12 of the frequency f ₁ from the terminal 11 can be input to the transistor without affecting the other.

The rat race hybrid 120 shown in FIG. 6 is bent to reduce the occupied area. The rat race hybrid 120 is not limited to the example shown in FIG. FIG. 4
Then rat race hybrid 120, matching circuit 62
Although a and 62b and reflectors 64a and 64b show examples using microstrip lines, coplanar lines may be used. FIG. 4 shows an example of integration,
The present invention is not limited to this, and various rat race hybrids and an integrated circuit of an amplifier or a frequency converter can be considered.

[0045]

According to the above configuration, a rat race hybrid having two input terminals and two output terminals separated from each other and having excellent isolation between input and output can be constructed. By using the present invention, a small high-frequency circuit having excellent characteristics can be realized.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a rat race hybrid according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a rat race hybrid according to a second embodiment of the present invention.

FIG. 3 is a top view of a microstrip line according to a second embodiment of the present invention.

FIG. 4 is a configuration diagram of a rat race hybrid according to a third embodiment of the present invention.

FIG. 5 is a top view of a coplanar waveguide according to a third embodiment of the present invention.

FIG. 6 is a top view of a down converter according to a fourth embodiment of the present invention.

FIG. 7 is a configuration diagram of a conventional rat race hybrid.

FIG. 8 is a configuration diagram of a conventional rat race hybrid.

[Explanation of symbols]

1, 2, 3, 4, 5, 6, 7, 8 Transmission line 11, 12, 13, 14, 15, 16, 17, 18 Terminal 21, 22, 23, 24, 25, 26, 27, 28 Microstrip Line 31, 51 Signal line 32, 50a, 50b Ground conductor 33, 52 Substrate 41, 42, 43, 44, 45, 46, 47, 48 Coplanar line 49 Air bridge

Claims (3)

[Claims] 1. A characteristic impedance 2 ^0.5 × Zo, the first transmission line and one of one terminal connected characteristic impedance 2 ^0.5 × Zo to a terminal of the first transmission line of electrical length 90 °, the electrical length a second transmission line of 90 °, and a second to the other terminal of the transmission line is one terminal connected characteristic impedance 2 ^0.5 × Zo, electrical length 90 ° of the third transmission line, the third transmission One terminal is connected to the other terminal of the line,
The other terminal of the first connected to the terminal of the transmission line characteristic impedance 2 ^0.5 × Zo, and the fourth transmission line of electrical length 270 °, to the connection point of the first transmission line and a second transmission line A fifth transmission line having a characteristic impedance Zo to which one terminal is connected; a sixth transmission line having a characteristic impedance Zo having one terminal connected to a connection point between the second transmission line and the third transmission line; A seventh transmission line having a characteristic impedance Zo in which one terminal is connected to a connection point between the third transmission line and the fourth transmission line, and one connection point between the fourth transmission line and the first transmission line. The eighth transmission line of the characteristic impedance Zo to which the terminal of the first transmission line, the fourth transmission line, and the eighth transmission line are connected on the fourth transmission line. At 90 °, the fifth transmission line and the fourth transmission line Is a rat race hybrid characterized by crossing spatially. 2. The first, second, third, fourth, fifth, sixth,
The seventh and eighth transmission lines are microstrip lines formed on a substrate, and the fifth transmission line and the fourth transmission line are arranged such that one of the transmission lines has a space on the other transmission line. The rat race hybrid according to claim 1, wherein the hybrid crosses while avoiding the obstacle. 3. The first, second, third, fourth, fifth, sixth,
The seventh and eighth transmission lines are coplanar lines formed on a substrate, and the fifth transmission line and the fourth transmission line are configured such that one of the transmission lines is spatially separated from the other transmission line. The rat race hybrid according to claim 1, wherein the intersection crosses while avoiding the above.