JPH08186449A - Frequency converter - Google Patents

Abstract

PURPOSE: To reduce the number of circuit elements consisting of the frequency converter for simultaneously providing the suppression of local power leak and the suppression of an image frequency signal. CONSTITUTION: This device is provided with a first distributing means 112 for distributing a high frequency signal as the object of frequency conversion with the phase difference of almost γ, power distributor 100 for distributing a local signal with a prescribed phase, amplitude and phase adjusting means 102 for adjusting the amplitude and phase of one of distributed local signals, second distributing means 106 for branching the other one of distributed local signals with the phase difference of almost β, and first and second non-linear elements 108 and 110 for multiplying the respective local signals outputted from the second distributing means 106 and the respective high frequency signals outputted from the first distributing means 112. Then, a power synthesizer 104 is provided to synthesize two outputs from two non-linear elements 108 and 110 with the phase difference of almost δ and to further perform in-phase synthesization to the result with the output of the amplitude and phase adjusting means 102. Among β, γ and δ, specified relation is established according to whether converting the intermediate frequency to a radio frequency or converting the radio frequency to the intermediate frequency.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a frequency converter in a radio frequency band, and more particularly to a frequency converter that simultaneously suppresses local power leakage and image frequency (image) signal suppression.

[0002]

2. Description of the Related Art An example of a conventional frequency converter used for the same purpose is shown in FIG. In the circuit 1 of FIG. 4, since the image signals are combined in opposite phases, they are not output,
Only local power and the desired high frequency output is output.
The circuit 2 operates similarly. The outputs of the circuit 1 and the circuit 2 are combined by the power combiner 5, but the local power is combined in the opposite phase and the desired high frequency output is combined in the same phase, and only the desired high frequency output is output to the RF terminal.

[0003]

This conventional frequency converter requires nine hybrids and four non-linear elements for multiplication, and further requires a matching circuit for each non-linear element. Therefore, the structure is complicated and the circuit scale is large.

It is an object of the present invention to provide a frequency converter with a reduced number of circuit elements.

[0005]

The features of the present invention for achieving the above-mentioned object are the first distributing means for distributing a high frequency signal to be frequency-converted with a phase difference of approximately γ, and a predetermined local signal. A power distributor for distributing in phase, an amplitude / phase adjusting means for adjusting one amplitude and phase of the distributed local signal, and a second distributing means for branching the other of the distributed local signals with a phase difference of approximately β. And first and second non-linear elements for multiplying each of the local signals output from the second distributing means and each of the high frequency signals output from the first distributing means, and the two non-linear elements. When the two outputs of the elements are combined with a phase difference of approximately δ and the intermediate frequency is converted to a radio frequency, β + γ + δ = 2nπ and β−γ + δ = (2n + 1) π or β + γ + δ = (2n + 1) π and β−γ + δ =
2nπ n is an integer, and when converting a radio frequency to an intermediate frequency, β−γ + δ = 2nπ and −β + γ + δ = (2n + 1) π or β−γ + δ = (2n + 1) π and −β + γ + δ
= 2nπ n is an integer, and the frequency converter further includes a power combiner that performs in-phase combination with the output of the amplitude / phase adjusting means.

[0006]

Embodiment 1 FIG. 1 shows an embodiment of the present invention. The frequency converter of the present invention outputs a local signal input to the LO terminal to 2
The power divider 100 that branches into two, the dividing means 106 that branches one of the branched local signals into two local signals having a phase difference of approximately β, and the IF signal or the RF signal to be frequency-converted into approximately γ. Distribution means 112 for branching into two signals of phase difference and two distribution means 106, 112.
Two nonlinear elements 108, 110 for multiplying each output of
And a power combiner 104 that combines the outputs of the two nonlinear elements with a phase difference of approximately δ and combines the other of the local signals branched by the power distributor 100 via the amplitude / phase adjusting means 102. . The frequency-converted signal is output from the power combiner 104.

The following relationships are established between the phase differences β, γ and δ. (A) When converting the intermediate frequency to a radio frequency, β + γ + δ = 2nπ and β−γ + δ = (2n + 1) π or β + γ + δ = (2n + 1) π and β−γ + δ =
2nπ n is an integer (b) β-γ + δ = 2nπ and −β + γ + δ = (2n + 1) π or β−γ + δ = (2n + 1) π and −β + γ + δ when converting a radio frequency to an intermediate frequency
= 2nπ n is an integer.

[0008]

[Embodiment 2] FIG. 2 shows an embodiment of the present invention. here,
The phase difference between the input and output of the hybrid 5 is α and α + π /
2, the phase difference between the input and output of the nonlinear elements 6 and 7 is θ, and the phase difference between the input and output of the power combiner 8 is φ, and ψ = α + θ +
φ + 5 / 4π. Further, the amplitude of the local leakage power output from the non-linear elements 6 and 7 when the local power having the amplitude A is given is a.

The IF signal is bifurcated by the hybrid 1 with a phase difference of 90 degrees and supplied to the non-linear elements 6 and 7, respectively. The local power is split into two by the power distributor 2, one of which is split into two by the hybrid 5 with a phase difference of 90 degrees and supplied to the nonlinear elements 6 and 7, respectively. The outputs of the non-linear elements 6 and 7 are combined by the power combiner 8. At this time, the image frequency components are combined in anti-phase and attenuated.

The other output of the power distributor 2 is output by the amplitude / phase adjusting means 3 as a local signal having the same power as the output of the power combiner 8 and a phase difference π with the output of the power combiner 8.

FIG. 3 shows the vector relation of the local power in this embodiment. Assuming that the input amplitude of the hybrid 5 is A and the phase is 0, the input amplitude A / √2 of the nonlinear element 6, the phase α, the input amplitude A / √2 of the nonlinear element 7, and the phase α + π /
It is 2. Since the phases of the non-linear elements 6 and 7 change by θ, the amplitude a / √2 of the output of the non-linear element 6 and the phase α + θ,
The amplitude a / √2 of the output of the non-linear element 7 and the phase α + θ + π /
It is 2. Therefore, the output combined by the power combiner 8 has the amplitude a and the phase α + θ + φ + π / 4.

On the other hand, the other output of the power distributor 2 is output by the amplitude / phase adjusting means 3 as a local signal of amplitude a and phase ψ.

Due to the effects described above, in the power combiner 9, the local signals are combined in opposite phases and attenuated, and only the desired wave is obtained.

[0014]

Third Embodiment FIG. 6 shows another embodiment of the present invention. The IF signal is branched into two by the hybrid 1 with a phase difference of 90 degrees and supplied to the nonlinear elements 6 and 7, respectively. The local power is split into two by the power distributor 2, one of which is split into two by the hybrid 5 with a phase difference of 90 degrees and supplied to the nonlinear elements 6 and 7, respectively. The outputs of the non-linear elements 6 and 7 are combined by the power combiner 8. At this time, the image frequency components are combined in anti-phase and attenuated.

The other output of the power divider 2 is the attenuator 10
3 and the phase shifter 104 output the same power as the output of the power combiner 8 and a local signal having a phase difference π with the output of the power combiner 8. Therefore, in the power combiner 9, the local signals are combined in the opposite phase and attenuated to obtain only the desired wave.

[0016]

Fourth Embodiment FIG. 7 shows another embodiment of the present invention. The IF signal is branched into two by the hybrid 1 with a phase difference of 90 degrees and supplied to the nonlinear elements 6 and 7, respectively. The local power is split into two by the power distributor 2, one of which is split into two by the hybrid 5 with a phase difference of 90 degrees and supplied to the nonlinear elements 6 and 7, respectively.

The other output of the power distributor 2 is output by the amplitude / phase adjusting means 3 as a local signal of power and phase shown in FIG.

In the power combiner 4, the outputs of the non-linear elements 6 and 7 and the amplitude / phase adjusting means 3 are combined in the vector relation of FIG. Therefore, the image frequency component and the local frequency component are combined in opposite phases and attenuated to obtain only the desired wave.

[0019]

Fifth Embodiment FIG. 8 shows another embodiment of the present invention. The IF signal is branched into two by the hybrid 1 with a phase difference of 90 degrees and supplied to the nonlinear elements 6 and 7, respectively. The local power is split into three by the power distributor 205, and one of them is output as a local signal of the power and phase shown in FIG.

Others have a non-linear element 6 having a phase difference of 90 degrees,
7 are supplied respectively. The outputs of the nonlinear elements 6 and 7 are
The power frequency combiner 8 combines the image frequency components in the opposite phase and attenuates.

In the power combiner 9, the output of the amplitude / phase adjusting means 3 and the output of the power combiner 8 are combined. At this time, the local frequency components are combined and attenuated in a vector relationship as shown in FIG. 3, and only the desired wave is obtained.

[0022]

Sixth Embodiment FIG. 9 shows another embodiment of the present invention. The IF signal is branched into two by the hybrid 1 with a phase difference of 90 degrees and supplied to the nonlinear elements 6 and 7, respectively. The local power is split into two by the power distributor 2, one of which is split into two by the hybrid 5 with a phase difference of 90 degrees and supplied to the nonlinear elements 6 and 7, respectively. The outputs of the non-linear elements 6 and 7 are combined by the power combiner 8. At this time, the image frequency components are combined in anti-phase and attenuated.

The power combiner 203 combines the other output of the power distributor 2 and the output of the power combiner 8 in a power ratio and a phase relationship so as to have the same amplitude and opposite phase. Therefore, the local signals are combined and attenuated by the vector relationship shown in FIG. 3, and only the desired wave is obtained.

[0024]

Seventh Embodiment FIG. 10 shows another embodiment of the present invention. IF
The signal is split into two by the hybrid 1 with a phase difference of 90 degrees and supplied to the nonlinear elements 6 and 7, respectively. The local power is branched into two by the power distributor 2, one of which is branched into two by the hybrid 5 with a phase difference of 90 degrees and supplied to the nonlinear elements 6 and 7, respectively. The outputs of the nonlinear elements 6 and 7 are combined by the power combiner 8,
At this time, the image frequency components are combined in opposite phases and attenuated.

The other output of the power distributor 2 is output as a local signal of power and phase as shown in FIG. 3 by the variable phase shifter 101, the variable attenuator 102 and the amplitude / phase adjusting means 3.

In the power combiner 9, the output of the amplitude / phase adjusting means 3 and the output of the power combiner 8 are combined. Therefore, the local signals are combined and attenuated in a vector relationship as shown in FIG. 3, and only the desired wave is obtained.

[0027]

Eighth Embodiment FIG. 11 shows another embodiment of the present invention. RF
The signal is split into two in the same phase and at the same level by the hybrid 208 and supplied to the non-linear elements 6 and 7, respectively.
The local power is split into two by the power distributor 2, one of which is split into two by the 90-degree hybrid 5 with a 90-degree phase difference and supplied to the non-linear elements 6 and 7, respectively. The outputs of the non-linear elements 6 and 7 are 90 degree hybrid 2
09, but at this time, the image frequency components are combined in anti-phase and attenuated.

The other output of the power distributor 2 is output by the amplitude / phase adjusting means 3 as a local signal of power and phase shown in FIG. Therefore, in the power combiner 210,
The local signals are combined in anti-phase and attenuated to obtain only the desired wave.

[0029]

Ninth Embodiment FIG. 12 shows another embodiment of the present invention. Here, the phase difference between the input and output of the hybrid 5 is α and α +
π / 2, the phase difference between the inputs and outputs of the nonlinear elements 3, 6, 7 is θ, the phase difference between the inputs and outputs of the power combiner 8 is φ, and ψ =
α + φ + 5 / 4π. Further, the amplitude of the local leakage power output from the non-linear elements 3, 6 and 7 when the local power having the amplitude A is given is a.

The IF signal is bifurcated by the hybrid 1 with a phase difference of 90 degrees and supplied to the non-linear elements 6 and 7, respectively. The local power is supplied to the power divider 2 and the phase difference ψ
And it is branched into two with the same electric power, and one of them is branched into two with a phase difference of 90 degrees by the hybrid 5, and the nonlinear element 6,
7 are supplied respectively. The outputs of the nonlinear elements 6 and 7 are
The power frequency combiner 8 combines the image frequency components in the opposite phase and attenuates.

The other output of the power distributor 2 is supplied to the non-linear element 3. In the power combiner 9, the output of the power combiner 8 and the output of the nonlinear element 3 are combined. FIG. 13 shows the vector relationship of the local power at this time.

Assuming that the input amplitude of the hybrid 5 is A and the phase is 0, the input amplitude A / √2 of the nonlinear element 6, the phase α, the input amplitude A / √2 of the nonlinear element 7, and the phase α + π /
It is 2. Since the phases of the non-linear elements 6 and 7 change by θ, the amplitude a / √2 of the output of the non-linear element 6 and the phase α + θ,
The amplitude a / √2 of the output of the non-linear element 7 and the phase α + θ + π /
It is 2. Therefore, the output combined by the power combiner 8 has the amplitude a and the phase α + θ + φ + π / 4.

On the other hand, the amplitude A of the input of the nonlinear element 3 and the phase ψ = α + φ + 5π / 4. Since the phase of the non-linear element 3 changes by θ, the amplitude a of the output of the non-linear element 3 and the phase α
It becomes + θ + φ + 5π / 4.

Therefore, as shown in FIG. 13, in the power combiner 9, the output of the non-linear element 3 and the output of the power combiner 8 are combined and attenuated by the same amplitude and opposite phase.

Due to the effects described above, only the desired wave is output from the power combiner 9.

[0036]

As described above, the frequency converter of the present invention requires no more than five hybrids or the like for distributing / combining electric power and only two non-linear elements for multiplying, and thus the conventional frequency converter. You can get the same effect as the container (Fig. 5). Moreover, since the number of nonlinear elements is small, the number of matching circuits can be small.
Further, since the attenuation amount of the attenuator and the phase amount of the phase shifter are determined by the characteristics of the non-linear element, they can be changed by adjusting the power distribution ratio and the phase difference of the power distributor 2 in advance. Therefore, it is possible to reduce the size and cost of the conventional frequency converter that can obtain the same effect. In addition to the above effects, when a non-linear element having the same characteristics as the first and second non-linear elements is used as one means of the amplitude / phase adjusting means, it also has a temperature correction effect.

[Brief description of drawings]

FIG. 1 is an example of the present invention.

FIG. 2 is a configuration diagram showing an embodiment of the present invention.

FIG. 3 is a vector diagram showing a phase relationship of local power.

FIG. 4 is a diagram showing a conventional frequency converter.

FIG. 5A is a diagram showing characteristics of this example.

FIG. 5B is a diagram showing characteristics of a conventional frequency converter.

FIG. 6 is a configuration diagram showing an embodiment of the present invention.

FIG. 7 is a configuration diagram showing an embodiment of the present invention.

FIG. 8 is a configuration diagram showing an embodiment of the present invention.

FIG. 9 is a configuration diagram showing an embodiment of the present invention.

FIG. 10 is a configuration diagram showing an embodiment of the present invention.

FIG. 11 is a configuration diagram showing an embodiment of the present invention.

FIG. 12 is a configuration diagram showing an embodiment of the present invention.

FIG. 13 is a vector diagram showing the phase relationship of local power.

[Explanation of symbols]

 100 Power Distributor 102 Amplitude and Phase Adjusting Means 104 Power Combiner 106 Distributing Means 108, 110 Nonlinear Element 112 Distributing Means

[Procedure amendment]

[Submission date] February 24, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 1

[Correction method] Change

[Correction content]

Claims (8)

[Claims] 1. A high-frequency signal to be frequency-converted is approximately γ
First distributing means for distributing with a phase difference of, a power distributor for distributing a local signal with a predetermined phase, and amplitude / phase adjusting means for adjusting one amplitude and phase of the distributed local signal, Second distributing means for branching the other of the local signals to approximately β with a phase difference; each of the output local signals of the second distributing means and the first
The first and second non-linear elements that multiply each of the high-frequency signals of the output of the distributing means and the two outputs of the two non-linear elements are combined with a phase difference δ, where the intermediate frequency is wireless. When converting to frequency, β + γ + δ = 2nπ and β−γ + δ = (2n + 1) π or β + γ + δ = (2n + 1) π and β−γ + δ =
2nπ n is an integer, and when converting a radio frequency to an intermediate frequency, β−γ + δ = 2nπ and −β + γ + δ = (2n + 1) π or β−γ + δ = (2n + 1) π and β + γ + δ =
2nπ n is an integer, and further has a power combiner for performing in-phase combination with the output of the amplitude / phase adjusting means. 2. The power combiner comprises a first power combiner for in-phase combining the two outputs of the two nonlinear elements, and a second power combiner for in-phase combining the output thereof with the output of the amplitude / phase adjusting means. 2. A frequency converter according to claim 1, comprising a power combiner according to claim 1. 3. The frequency converter according to claim 1, wherein the power distributor and the second distributor are realized by a single power distributor having three outputs. 4. The frequency converter according to claim 1, wherein the power distributor is realized by a power distributor that distributes in-phase and a unit that gives a predetermined phase difference to each distribution output. 5. When converting the intermediate frequency to a radio frequency, β = π / 2, γ = π / 2, δ = 0 or β = 0, γ = π / 2, δ = π / 2 are satisfied, and The frequency converter according to claim 1, wherein β = 0, γ = π / 2, δ = π / 2 or β = π / 2, γ = 0, δ = π / 2 when the frequency is converted to the intermediate frequency. . 6. The phase divider and the power combiner or the phase difference and the power divider of either one or both of the phase change amount and the amplitude change amount given by the amplitude / phase adjusting means are small, or both. The frequency converter according to claim 1, wherein the frequency converter is provided by a synthesis ratio. 7. The frequency converter according to claim 1, wherein the amount of change in the phase and / or the amplitude provided by the amplitude / phase adjusting means is variable. 8. The frequency converter according to claim 1, wherein a non-linear element having the same characteristics as those of the first and second non-linear elements is used as one means of the amplitude / phase adjusting means.