JPH06283935A - Frequency converter - Google Patents

Abstract

PURPOSE:To provide a frequency converter which can eliminate a local wave and an odd-order higher harmonic of the local wave without limiting the frequency relation between the signal and local waves. CONSTITUTION:A local wave is supplied to a 1st terminal 17a of an input 90 deg.-hybrid circuit 17, and a 1st balance circuit 7 containing a Schottky barrier diode 11 is connected to a 2nd terminal 17b of the circuit 17. Then a 2nd balance circuit 8 which contains a Schottky barrier diode 12 and a signal wave input terminal 10a is connected to a 4th terminal 17d of the circuit 17. Meanwhile a 2nd terminal 22 b of an output 90 deg.-hybrid circuit 22 is connected to the output terminal of the circuit 7, and a 4th terminal 22d of the circuit 22 is connected to the output terminal of the circuit 8 respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a frequency converter called an up converter for converting a signal frequency into another high frequency in a communication device in the UHF band, the microwave band and the millimeter wave band.

[0002]

2. Description of the Related Art FIG. 3 shows the most basic configuration of a conventional frequency converter of this type using a Schottky barrier diode as a non-linear element for forming a mixed wave.

[0003] The frequency converter has an input terminal 1a, was combined by multiplexer 2 the local wave f _l signal wave f _s and the frequency f _l of a frequency f _s input from 1b, the Schottky barrier diode 3 It is designed to be input to the anode of. The Schottky barrier diode 3 has its cathode grounded. Schottky barrier diode 3
A bandpass filter 4 is connected to the anode of the, and an output end 5 is provided on the output side of the bandpass filter 4.

In such a frequency converter, when the signal wave f _s and the local wave f _l are input to the anode of the Schottky barrier diode 3, the following mixed wave signal f _M is obtained due to its nonlinear characteristics. To be

[0005] _{f M = ± mf s ± nf} l formula (1) wherein, m and n are integers comprised from 0, 1, 2, 3 ....

The state of this mixed wave signal f _M is shown in FIG.
Among the unnecessary waves in the mixed wave signal f _M , the local wave f _l has the highest level and is close to the desired wave f _i (= f _s + f _l ).

The mixed wave signal f _M output from the anode of the Schottky barrier diode 3 is filtered by the band pass filter 4 to obtain a desired wave f _i (= f _s + f _l ).

However, in the method of removing the unwanted wave by using the bandpass filter 4 as described above, the bandpass filter 4 has to be constructed in multiple stages, and there is a problem that the size becomes large and the cost becomes high.

As a frequency converter which solves such a problem and removes a part of unnecessary waves, a frequency converter as shown in FIG.
A balanced circuit configuration using two hybrid circuits has been proposed.

The input side of this frequency converter has first, second, third and fourth terminals 6a to 6d, and the line length between the adjacent first to fourth terminals 6a to 6d. Is provided with an input 180 ° hybrid circuit 6 having an electrical angle of 90 ° and a line length between the fourth terminal 6d and the first terminal 6a of 270 ° in electrical angle. When the signal wave f _s is input to the first terminal 6a of the input 180 ° hybrid circuit 6, the second terminal 6b and the fourth terminal 6d have the same amplitude, and the phase difference between them is small. A 180 ° signal wave f _s is output. When the local wave f _l is input to the third terminal 6c of the input 180 ° hybrid circuit 6, the second terminal 6b and the fourth terminal 6d have the same amplitude and a phase difference between them. There is no local wave f _l .

The second of the input 180 ° hybrid circuit 6
The first balance circuit 7 is connected to the terminal 6b, and the second balance circuit 8 is connected to the fourth terminal 6d of the input 180 ° hybrid circuit 6. These first and second balance circuits 7 and 8 include matching circuits 19 and 20, a Schottky barrier diode 11 as a non-linear element,
12 and output matching circuits 13 and 14 are provided. In both the first and second balance circuits 7 and 8, the Schottky barrier diode 11 forms a mixed wave of the signal wave f _s and the local wave f _l .

The output side of this frequency converter has first, second, third and fourth terminals 15a to 15d, and the line length between adjacent first to fourth terminals 15a to 15d. Are 90 ° in electrical angle, and the fourth terminal 15d and the first terminal 1 are
The line length between 5a is 270 ° in electrical angle, and the terminating resistor 16 is connected to the third terminal 15c.
A 0 ° hybrid circuit 15 is provided. The second terminal 15b of the output 180 ° hybrid circuit 15 is connected to the output terminal of the first balance circuit 7, and the fourth terminal 1
5d is connected to the output terminal of the second balance circuit 8.

In such a frequency converter, when the signal wave f _s is input to the first terminal 6a of the input 180 ° hybrid circuit 6 and the local wave f _l is input to the third terminal 6c, A signal wave f _s having the same amplitude and a phase difference of 180 ° between them is output to the second terminal 6 b and the fourth terminal 6 d, and a local wave f _l having the same amplitude and phase is output.

The second of the 180 ° hybrid circuit 6 for input
The signal waves f _s and the local waves f _l output from the fourth terminals 6 b and 6 d are injected into the respective anodes of the Schottky barrier diodes 11 and 12 via the matching circuits 19 and 20, and these Schottky barrier diodes 11 are injected. , 12, a mixed wave of the signal wave f _s and the local wave f _l is formed.
The output of the first balance circuit 7 is input to the second terminal 15b of the output 180 ° hybrid circuit 15, and the output of the second balance circuit 8 is the output 180 ° hybrid circuit 15.
Is input to the fourth terminal 15d.

When these inputs are combined by the output 180 ° hybrid circuit 15, the frequency component f _ir f _ir = ± m _e f _s shown in the equation (2) among the mixed waves shown in the above equation (1). ± n _{o fl} equation (2) (where, m _e is an even number of 0, 2, 4, ..., n _o is 0, 1,
It is an odd number of 3. ) Is removed.

Such a frequency converter has an advantage of being able to remove the local wave f _l that is closest to the desired wave f _i and has a very high level among the unnecessary waves.

[0017]

However, in the conventional frequency converter shown in FIG. 5, both the signal wave f _s and the local wave f _l are input to the input 180 ° hybrid circuit 6. , The signal wave f _s and the local wave f _l
When the frequencies are significantly separated, the frequency band of the input 180 ° hybrid circuit 6 cannot cover this and there is a problem that a frequency converter using two 180 ° hybrid circuits cannot be adopted. . Regarding the band characteristics of the 180 ° hybrid circuit, in the case of the rat race ring as a 180 ° hybrid circuit that is often used in the microwave band, the usable band is approximately 2 as the ratio between the lower limit frequency and the upper limit frequency. It was below.

The object of the present invention is not limited by the frequency relationship between the signal wave and the local wave, and of the unnecessary waves, the local wave that is closest to the desired wave and has a high level and its higher harmonics. It is to provide a frequency converter capable of removing the noise.

[0019]

The constitution of the present invention which achieves the above object will be described as follows.

According to a first aspect of the present invention, there is provided a first, second, third and fourth terminal, the third terminal is non-reflection terminated, and a local wave is applied to the first terminal. 90 ° for input having a structure in which a local wave having a phase difference of 90 ° between the second terminal and the fourth terminal is output when is input.
A hybrid circuit, a first balance circuit connected to one output terminal of the input 90 ° hybrid circuit and forming a harmonic of the local wave with a Schottky barrier diode, and a signal wave input for inputting a signal wave End and a local wave input end connected to the other output terminal of the 90 ° hybrid circuit for input and a Schottky barrier diode, and the Schottky barrier diode forms a mixed wave of the signal wave and the local wave. A second balance circuit, and first, second, third and fourth terminals, wherein the third terminal is non-reflection terminated and the second terminal is the first terminal.
Is connected to the output terminal of the balance circuit and the fourth terminal is connected to the output terminal of the second balance circuit,
From the sum of the frequency of the local wave and the frequency of the signal wave, the local wave and its odd harmonics are eliminated from the output of the second balance circuit by the output of the first balance circuit. And a 90 ° hybrid circuit for output that obtains the desired wave output from the first terminal.

The invention according to claim 2 is provided with at least one input terminal and two output terminals, and when a local wave is input to the input terminal, the two output terminals output the same amplitude with the same amplitude. A 180 ° hybrid circuit for input having a structure in which the local wave having a phase difference of 180 ° is output, and a Schottky barrier diode connected to one of the output terminals of the 180 ° hybrid circuit for input to connect the local wave of the local wave. A first balance circuit for forming harmonics, a signal wave input end for inputting a signal wave, a local wave input end connected to the other output terminal of the input 180 ° hybrid circuit, and a Schottky barrier diode. A second balance circuit for forming a mixed wave of the signal wave and the local wave with the Schottky barrier diode; and at least two input terminals. The output of the first balance circuit input to one of the input terminals and the local wave from the output of the second balance circuit input to the other of the input terminals. An output common-mode hybrid circuit for eliminating the odd harmonics and obtaining a desired wave output composed of the sum of the frequency of the local wave and the frequency of the signal wave from the output terminal is provided. And

[0022]

When the local wave is input from the input 90 ° hybrid circuit and the signal wave is input from the second balance circuit, the frequency conversion is not limited by the frequency relationship between the signal wave and the local wave. Become a vessel.

In this frequency converter, if attention is paid only to local waves, the 90 ° hybrid circuit for input has the same amplitude in the first and second balance circuits having substantially the same performance, and the phase difference between them is 90. When a ° local wave is input, the 90 ° hybrid for output is output from these first and second balance circuits with the local wave and its odd harmonics having the same amplitude and a phase difference of 90 °. Second of the circuit
From the function of the 90 ° hybrid circuit, the local wave and its odd harmonics are output to the fourth terminal and guided to the third terminal of the 90 ° hybrid circuit for output and consumed by the non-reflective terminator. Even harmonics of the local wave are for the output
It is guided to the first terminal of the 90 ° hybrid circuit and output. That is, only the frequency obtained by removing the local wave and its odd harmonics is output to the first terminal of the 90 ° hybrid circuit for output. As a result, the desired wave f _i (= f _s + f
_It is possible to remove the local wave that is closest to _l ) and has a higher level and its higher harmonics.

Further, from the function of the 90 ° hybrid circuit,
The reflected waves of the local waves generated in the first and second balance circuits are all output to the third terminal of the 90 ° hybrid circuit for input and are absorbed by the non-reflecting terminator.
No reflected wave appears at the first terminal of the hybrid circuit.

Also in the case of claim 2, the local wave is for input 18
Since it is input from the 0 ° hybrid circuit and the signal wave is input from the second balance circuit, the frequency converter is not limited by the frequency relationship between the signal wave and the local wave.

Further, in this frequency converter, focusing on only the local wave, the input 180 ° hybrid circuit is changed to the first and second balance circuits having substantially the same performance with the same amplitude,
When a local wave with a phase difference of 180 ° is input,
From these first and second balance circuits, the local wave and its odd harmonics have the same amplitude, and their phase differences are different.
It is output to the two input terminals of the output in-phase hybrid circuit in the state of 180 °, of which the fundamental wave of the local wave and its odd harmonics are consumed by the output in-phase hybrid circuit and the even-order of the local wave. Is output from the output terminal of the output in-phase hybrid circuit. As a result, an output wave similar to that of claim 1 can be obtained.

The difference from the frequency converter of claim 1 is that the reflected wave of the local wave generated in the first and second balance circuits is directly discharged from the first terminal of the input 180 ° hybrid circuit. However, if the first and second balance circuits are matched with the local wave, no special problem will occur.

[0028]

Embodiments of the present invention will be described in detail below with reference to the drawings. In addition, in the portion corresponding to FIG. 5 described above,
The same reference numerals are given.

FIG. 1 shows a first frequency converter according to the present invention.
It shows an example. The frequency converter of the present embodiment is provided on the input side with an input 90 ° hybrid circuit 17 including a branch line coupler, a 3 dB directional coupler and the like. The input 90 ° hybrid circuit 17 includes
It has second, third, and fourth terminals 17a to 17d, the third terminal 17c is terminated by a non-reflection resistor 18 in a non-reflection manner, and the local wave f _l is input to the first terminal 17a. The second terminal 17b and the fourth terminal 17d output local waves f ₁ having the same amplitude and a mutual phase difference of 90 °.

Second input 90 ° hybrid circuit 17
The first balance circuit 7 is connected to the terminal 17b, and the second balance circuit 8 is connected to the fourth terminal 17d of the input 90 ° hybrid circuit 17.

The first and second balance circuits 7 and 8 include multiplexing circuits 9 and 10, input matching circuits 19 and 20, and Schottky barrier diodes 11 and 12 as non-linear elements.
And output matching circuits 13 and 14 including a high pass filter. Particularly, in the present invention, the multiplexing circuits 9 and 10 are provided with the signal input terminals 9a and 10a,
The non-reflection terminator 21 is connected to the signal input terminal 9a of the multiplexing circuit 9 on the first balance circuit 7 side, and the signal input terminal 10 of the multiplexing circuit 10 on the second balance circuit 8 side is connected.
The signal wave f _s is input to a. In such a first balance circuit 7, the Schottky barrier diode 11 forms the local wave f _l and its harmonics. In addition, in the second balance circuit 8, the Schottky barrier diode 12 forms a mixed wave of the local wave f _l and the signal wave f _s .

The frequency converter of this embodiment is provided with an output 90 ° hybrid circuit 22 including a branch line coupler and a 3 dB directional coupler on the output side. For the output
The 90 ° hybrid circuit 22 includes the first, second, third and fourth
Second terminals 22a to 22d, the third terminal 22c is non-reflectively terminated by the non-reflective resistor 23, and the second terminal 22c
b is connected to the output terminal of the first balance circuit 7 and
22d is connected to the output terminal of the second balance circuit 8, and the output of the first balance circuit 7 is the local wave f _l and its odd harmonics from the output of the second balance circuit 8. By eliminating and, the frequency of the local wave f _l and the signal wave f
Desired wave f _i (= f _s + f _l ) consisting of the sum of _s and frequency
The output is output from the first terminal 22a.

In such a frequency converter, when the local wave f _l is input to the first terminal 17a of the input 90 ° hybrid circuit 17, the amplitude thereof is equally divided by 1/2 ^1/2 and the mutual waves are mutually divided. The local wave f _l having a phase difference of 90 ° between them is output from the second terminal 17b and the fourth terminal 17d and injected into the first and second balance circuits 7 and 8.

The local wave f _l injected into the first balance circuit 7 passes through the multiplexing circuit 9 and is guided to the input matching circuit 19 where it is subjected to a matching action and then is applied to the anode of the Schottky barrier diode 11. By being injected and subjected to the frequency conversion action of the Schottky barrier diode 11, a harmonic of the local wave f _l is formed. The obtained harmonic of the local wave f _{l and} the fundamental wave of the local wave f _l are
It is guided to the output matching circuit 13 including a high-pass filter, receives the matching action, and outputs the second 90 ° hybrid circuit 22 for output.
Is injected into the terminal 22b.

On the other hand, it was injected into the second balance circuit 8.
The local wave f _l delayed by 90 ° is a signal wave f _l in the combining circuit 10.
_s , is guided to the input matching circuit 20, undergoes a matching action, and then injected into the anode of the Schottky barrier diode 12
The mixed wave f _M (= ± mf _{s of the} local wave f _l and the signal wave f _s shown in the equation (1) by the frequency conversion action of
± nf _l) is formed. This mixed wave f _M is guided to the output matching circuit 14 including a high-pass filter, frequency components lower than the cut-off frequency of the high-pass filter are greatly attenuated, and other frequency components are desired wave f _i (= f _s + f
It is injected into the fourth terminal 22d of the 90 ° hybrid circuit 22 for output with a matching action centered on _l ).

Here, in order to simplify the explanation, the first and second
Focusing only on the local wave f _l that has passed through the balance circuits 7 and 8, the first and second balance circuits 7 and 8 have substantially the same performance. second output 90 ° hybrid circuit 22 from the output of 7,8, a fourth terminal 22b, led to 22d and the local wave f _l of its harmonics, the local wave f _l
And their odd harmonics have the same amplitude and a phase difference of 90
°. Among these local wave f _l and its harmonics, the local wave f _{l is}
And its odd harmonics are 90 ° hybrid circuit for output 2
2 is led to the third terminal 22c of No. 2 and is consumed by the non-reflection terminator 23, and the even harmonics of the local wave f _l are for output.
The 90 ° hybrid circuit 22 is guided to the first terminal 22a and output. That is, the output 90 ° hybrid circuit 22
Only the frequency from which the local wave f _l and its odd harmonics are removed is output to the first terminal 22a of. As a result, it is possible to remove the local wave f _I and the odd harmonics thereof that are closest to the desired wave f _i (= f _s + f _l ) and have a high level.

Further, from the function of the 90 ° hybrid circuit,
The reflected waves of the local wave f _I generated in the first and second balance circuits 7 and 8 are all output to the third terminal 17c of the input 90 ° hybrid circuit 17 and absorbed by the non-reflection terminator 18. Therefore, the reflected wave does not appear at the first terminal 17a of the input 90 ° hybrid circuit 17.

Therefore, according to the invention of the first embodiment,
Since the local wave f _I is input from the input 90 ° hybrid circuit 17 and the signal wave f _s is input from the second balance circuit 8, there is no restriction on the frequency relationship between the signal wave f _s and the local wave f _I. Therefore, it is possible to provide a frequency converter that can remove the local wave f _I and the odd harmonics thereof that are closest to the desired wave f _i and have a high level among the unnecessary waves.

FIG. 2 shows a second frequency converter according to the present invention.
It shows an example. The frequency converter of the present embodiment has an input terminal called a rat race ring.
A 0 ° hybrid circuit 6 is provided. 180 ° for the input
The hybrid circuit 6 has first, second, third, and fourth terminals 6a to 6d, and the line lengths between the adjacent terminals 6a to 6d are 90 ° in electrical angle, respectively, and the fourth terminal 6d. First
The line length between the terminals 6a is 270 ° in electrical angle,
When the third terminal 6c is non-reflection terminated by the non-reflecting terminator 24 and the local wave f _I is input to the first terminal 6a, the second terminal 6b and the fourth terminal 6d have the same amplitude. so,
The structure is such that local waves f _I having a mutual phase difference of 180 ° are output.

Second input 180 ° hybrid circuit 6
The first balance circuit 7 is connected to the terminal 6b, and the second balance circuit 8 is connected to the fourth terminal 6d of the input 180 ° hybrid circuit 6. The internal configurations of the first and second balance circuits 7 and 8 are similar to those of the first embodiment described above.

The frequency converter of this embodiment is provided with an output in-phase hybrid circuit 25 called a Wilkinson distributor on the output side. The output in-phase hybrid circuit 25 includes a second terminal 3 and a third terminal 2 that function as input terminals.
5b, 25c and the first terminal 2 acting as an output terminal
5a, and the line length from the first terminal 25a to each of the second and third terminals 25b and 25c is 90 ° in electrical angle.
The resistor 26 is connected between the second terminal 25b and the third terminal 25c, the second terminal 25b is connected to the output terminal of the first balance circuit 7, and the third terminal 25c is connected.
c is connected to the second balance circuit 8, and the output of the first balance circuit 7 eliminates the local wave f _l and its odd harmonics from the output of the second balance circuit 8. The output of the desired wave f _i (= f _s + f _l ) which is the sum of the frequency of the local wave f _{l and} the frequency of the signal wave f _s is obtained from the first terminal 25a.

Next, the operation of such a frequency converter will be described. First 180 ° hybrid circuit 6 for input
When the local wave f _l is input to the terminal 6a of
0 ° second and fourth terminals 6b and 6d of the hybrid circuit 6
Output local waves f _l having the same amplitude and a phase difference of 180 ° from each other. The output of these local waves f _l is
It is input to the first and second balance circuits 7 and 8. Since the configurations of the first and second balance circuits 7 and 8 are the same as those of the first embodiment as described above, these first and second balance circuits 7 and 8 are the same.
The description of the operation of the second balance circuits 7 and 8 is omitted.

Here, the first and second balance circuits 7 and 8
Focusing only on the local wave f _l that has passed through, the first and second balance circuits 7 and 8 have almost the same performance.
Among the local wave f _l and its harmonics respectively injected into the third terminals 25b and 25c, the local wave f _l and its odd harmonics have the same amplitude, and their phase difference is 180 °.
Is. Of these local waves f _l and its harmonics,
The local wave f _l and its odd-order harmonics are consumed by the resistor 26 of the output in-phase hybrid circuit 25, and the even-order harmonic of the local wave f _{l is} the first harmonic of the output in-phase hybrid circuit 25. It is output from the terminal 25a. As a result, an output wave similar to that of claim 1 can be obtained.

The difference from the frequency converter of the first embodiment is that the local wave f generated in the first and second balance circuits 7 and 8 is generated.
The reflected wave of _l is discharged from the first terminal 6a of the input 180 ° hybrid circuit 6 as it is, but the first and second balance circuits 7 and 8 are matched with the local wave f _l . If this is done, no special problems will occur.

Also in the case of the second embodiment, the local wave f _l
Is input from the input 180 ° hybrid circuit 6 and the signal wave f _s is input from the second balance circuit 8. Therefore, the frequency converter is not limited by the frequency relationship between the signal wave f _s and the local wave f _l. .

The frequency converters of the first and second embodiments as described above have been described above when the device is constituted by the microwave integrated circuit MIC or the microwave monolithic integrated circuit MMIC, which requires miniaturization and cost reduction. There is an advantage that the external filter can be small and simple.

Further, each 180 ° hybrid circuit is not limited to the rat race ring, but a balun or the like using a magic T or a toroidal core can be used.

Further, the output in-phase hybrid circuit 25 is not limited to the Wilkinson type distributor, but may be the one shown in FIG.
It is also possible to use the 180 ° hybrid circuit 15 or the like for output of. In this case, the second terminal 15b and the fourth terminal 15d of the output 180 ° hybrid circuit 15 are used as two input terminals, the third terminal 15c is used as an output terminal, and the first terminal 15a is used. Is non-reflectively terminated by the terminating resistor 16.

[0049]

As described above, according to the frequency converter of the present invention, the following excellent effects can be obtained.

In the frequency converter according to the first aspect, since the local wave is input from the input 90 ° hybrid circuit and the signal wave is input from the second balance circuit, the frequency relationship between the signal wave and the local wave. It is possible to provide a frequency converter that is not limited to the above.

Further, this frequency converter has the same first and second performances as the 90 ° hybrid circuit for input.
When a local wave with the same amplitude and a phase difference of 90 ° is input to the balance circuit of, the local wave and its odd harmonics have the same amplitude from the first and second balance circuits, respectively. The phase difference of 90 ° is output to the second and fourth terminals of the 90 ° hybrid circuit for output, and due to the function of the 90 ° hybrid circuit, the local wave and its odd harmonics are ° The higher harmonics of the local wave, which are guided to the third terminal of the hybrid circuit and consumed by the non-reflective terminator, are the first harmonics of the 90 ° hybrid circuit for output.
Will be output to the terminal of. That is, for output
Only the frequency from which the local wave and its odd harmonics are removed is output to the first terminal of the 90 ° hybrid circuit. As a result, according to the first aspect of the present invention, it is possible to remove the local wave that is closest to the desired wave and has a high level, and the odd harmonics thereof.

Further, from the function of the 90 ° hybrid circuit,
The reflected waves of the local waves generated in the first and second balance circuits are all output to the third terminal of the 90 ° hybrid circuit for input and are absorbed by the non-reflecting terminator.
There is an advantage that the reflected wave does not appear at the first terminal of the hybrid circuit.

Further, in the present invention, since the Schottky barrier diode is used as the nonlinear element, there is an advantage that a bias circuit for the nonlinear element is unnecessary.

In the frequency converter according to the second aspect, since the local wave is input from the input 180 ° hybrid circuit and the signal wave is input from the second balance circuit, the frequency relationship between the signal wave and the local wave is limited. It is possible to provide a frequency converter that does not receive the voltage.

Further, this frequency converter has an input 180 °
From the hybrid circuit to the first and second balance circuits having almost the same performance, the amplitude is the same and the phase difference between them is 18
A 0 ° local wave is input, and the local wave and its odd harmonics have the same amplitude from these first and second balance circuits, and the phase difference between them is 180 °. The local wave and its odd harmonics are output to two input terminals, and the local harmonics and the odd harmonics thereof are consumed by the output in-phase hybrid circuit, and the even harmonics of the local wave are output from the output terminal of the output in-phase hybrid circuit. Will be output. As a result, an output wave similar to that of claim 1 can be obtained.

Also, in the present invention, since the Schottky barrier diode is used as the non-linear element, there is an advantage that a bias circuit for the non-linear element is unnecessary.

[Brief description of drawings]

FIG. 1 is a block circuit diagram of a first embodiment of a frequency converter according to the present invention.

FIG. 2 is a block circuit diagram of a second embodiment of the frequency converter of the invention.

FIG. 3 is a block circuit diagram of a frequency converter using a conventional bandpass filter.

FIG. 4 is a frequency spectrum diagram of a local wave and a signal wave whose frequency is converted by a Schottky barrier diode.

FIG. 5 is a block circuit diagram of a conventional frequency converter using two 180 ° hybrid circuits.

[Explanation of symbols]

 1a, 1b Input terminal 2 Multiplexer 3 Schottky barrier diode 4 Bandpass filter 5 Output terminal 6 180 ° hybrid circuit for input 6a to 6d 1st, 2nd, 3rd and 4th terminals 7 1st balance circuit 8 Second balance circuit 9,10 Multiplexing circuit 11,12 Schottky barrier diode 13,14 Output matching circuit 15 Output 180 ° hybrid circuit 15a to 15d First, second, third and fourth terminals 16 Termination Resistor 17 90 ° hybrid circuit for input 17a to 17d 1st, 2nd, 3rd and 4th terminal 18 Non-reflective resistor 19 and 20 Input matching circuit 21 Non-reflective terminator 22 90 ° hybrid circuit for output 22a to 22d 1st, 2nd, 3rd and 4th terminals 23, 24 Non-reflective resistor 25 In-phase hybrid circuit for output 25a to 25c 1st, 1st, 2nd and 3rd terminals 26 Resistance

Claims (2)

[Claims] 1. A first terminal, a second terminal, a third terminal and a fourth terminal,
When the third terminal is non-reflection terminated and a local wave is input to the first terminal, a local phase difference of 90 ° is generated between the second terminal and the fourth terminal. A 90 ° hybrid circuit for input having a structure for outputting a wave, and a first 90 ° hybrid circuit connected to the second terminal of the 90 ° hybrid circuit for input to form a harmonic of the local wave with a Schottky barrier diode. A balance circuit, a signal wave input end for inputting a signal wave, a local wave input end connected to the fourth terminal of the input 90 ° hybrid circuit, and a Schottky barrier diode are provided. A second balance circuit that forms a mixed wave of the signal wave and the local wave; and first, second, third, and fourth terminals, wherein the third terminal is non-reflection terminated, and The second terminal is the front The first balance circuit is connected to the output terminal and the fourth terminal is connected to the output terminal of the second balance circuit,
The desired wave composed of the sum of the frequency of the local wave and the frequency of the signal wave by eliminating the local wave and its odd harmonics from the output of the second balance circuit by the output of the second balance circuit. For output to obtain output from the first terminal
A frequency converter having a 90 ° hybrid circuit. 2. The apparatus having at least one input terminal and two output terminals, wherein when a local wave is input to the input terminals, the two output terminals have the same amplitude and a phase difference of 180 ° from each other. For input of a structure that outputs a local wave 18
A 0 ° hybrid circuit, a first balance circuit connected to one of the output terminals of the input 180 ° hybrid circuit and forming a harmonic of the local wave by a Schottky barrier diode, and a signal wave are input. A signal wave input end and a local wave input end connected to the other output terminal of the input 180 ° hybrid circuit and a Schottky barrier diode,
A second balance circuit that forms a mixed wave of the signal wave and the local wave with the Schottky barrier diode; and at least two input terminals and one output terminal,
The output of the first balance circuit that is input to one of the input terminals, and the second output that is input to the other of the input terminals
Output from the output terminal by eliminating the local wave and its odd harmonics from the output of the balance circuit, and obtaining a desired wave output consisting of the sum of the frequency of the local wave and the frequency of the signal wave And a common-mode hybrid circuit for use with the frequency converter.