JPS6135007A - Phase shifter - Google Patents

Abstract

PURPOSE:To attain broad band of a phase shifter independently of an input signal frequency by distributing a phase of an input signal, applying frequency conversion to the result and applying in-phase synthesis, then phase distribution, delay frequency conversion and opposite-phase synthesis. CONSTITUTION:The input signal is distributed by a phase difference of 90 deg. by a distributor 22, synthesized with a phase difference 0 at a synthesizer 23 via frequency converters 18, 19, distributed by a phase difference of 90 deg. by a distributor 24 and synthesized by an inverse phase synthesizer 25 via frequency converters 20, 21. In this case, a signal from a local oscillator 16 is given to the converters 18, 19 via a distributor 26 and an output of the oscillator 16 is given to the converters 20, 21 via a variable delay line 17 and a 90 deg. distributor 27. As a result, an output signal of the synthesizer 25 is a signal having a prescribed phase shift amount phi decided by the line 17 to an input signal.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a phase shifter with broadband characteristics.

(Prior Art) Generally, a phase shifter is used to arbitrarily set or vary the phase difference between an input signal and an output signal. Conventionally,
As this type of phase shift circuit, a configuration as shown in FIG. 3 or 4 has been considered.

In FIG. 3, a variable capacitor Cs (C) and an inductance Ls (Lx) and a variable reactance element connected in series with a 9δ hybrid 11 are used. In this case, capacitors C1 and C.

Here, Zo is the characteristic impedance of each terminal of the 9δ hybrid.

As can be seen from this equation, the amount of phase shift ψ is a function of the angular frequency W of the input signal, and the amount of phase shift ψ is approximately constant only within a certain range of the frequency of the input signal. As a phase shifter, it had a narrow band and had poor frequency characteristics that caused group delay distortion. .

Next, in the phase shifter having the configuration shown in FIG. 4, the input signal is converted to the input signal frequency f! by the local oscillation source 16 and the frequency converter 12. and the local oscillation source 160 frequency f, the sum and difference frequencies '1+'Ls and fl-fl.

is converted to After one of these frequencies is removed by the next band ψ wave converter 14, the frequency converter 13
As a result, a phase shift change proportional to the delay time of the variable delay line 17 is applied, and the frequency is returned to the original frequency fI. At this time, since the output of the frequency converter 3 contains unnecessary high frequencies other than the input signal station wave number, only the input signal frequency is extracted by the bandpass filter 15.

The amount of phase shift in this circuit is given by the product of the angular frequency of the local oscillation source 160 and the MIA time of the delay line 17, and does not depend on the frequency of the input signal, so a wideband phase shift characteristic can be obtained for the input signal. , a band ψ wave transducer was required, and wideband customization was dependent on the characteristics of this band ψ wave transducer.

(Object of the Invention) An object of the present invention is to provide a phase shifter that eliminates such drawbacks and can handle broadband customization without using a Teijo waver.

(Structure of the Invention) The phase shifter of the present invention includes a first branching means for branching an input signal into two, and first and second frequency signals for frequency-converting the branched outputs by first and second frequency signals, respectively. a converting means, a first combining means that suppresses and combines one of the @band waves of the outputs of the frequency converting means 1 and the second frequency converting means, and a second combining means that branches the output of the first combining means into two. a branching means; third and fourth frequency converting means for frequency converting each output of the second branching means using a second frequency signal; and each of the third and fourth frequency converting means. a second synthesizing means for synthesizing outputs and extracting input signal components; a local oscillator for generating a predetermined frequency signal; and a variable delay line for providing a variable delay corresponding to a predetermined phase shift amount to the output of the local oscillator; and means for supplying the output of the variable delay line or the output of the local oscillator to each of the frequency conversion means as the first and second frequency signals, respectively.

(Example) Next, please refer to the drawings regarding the present invention.1. This will be explained in detail.

FIG. 1 is a block diagram of one embodiment of a phase shifter according to the present invention. In the figure, 18 to 21 are frequency converters, 16 is a local oscillation source, 17 is a variable delay line, 22.24.26.
27 is a 9δ distributor, z3 is an O (in-phase) combiner, 25 is a 1
80 (reverse phase) combiner.

Next, the operation of this circuit will be explained. Assuming that the input signal at the input terminal 1 is coswit and the signal from the local oscillation source is coswlt, the input signal is first distributed by the distributor 22 with a phase difference of 9δ, and the input signal is distributed at points 41 and 42 on the outputs of the frequency converters 18 and 19. The signals in are expressed as follows.

+ cos (wi-wl) t) ・ ... (2) cos (wit + 96)・cos (wlt +
9δ): Sin Wii m5jn wlt ...... (3) The outputs of these frequency converters 18 and 19 are combined in a synthesizer 23 with a phase difference of 0, and the signal at this output point 43 (2)
The sum of Equation and Equation (3) is as follows.

Cog (Wi-Wl)t...
(4) Next, the output of the synthesizer 23 is distributed by the distributor 24 with a phase difference of 9d, and is input to the frequency converter 20.degree.21. Point 44. on the output of frequency converter 20.21.
Signals 45 are expressed as shown in the following equations, assuming that the amount of phase shift by the variable delay line 17 is ψ.

cos (wi-wl)t・cos (wlt+g+)
......(5) Cog((Wi"-Wl)t+99)"
C05(Wlt+9'+96)=sin(
wi-Wl) t-sin (wit + 9+)...
...(6) The outputs of these frequency converters 20 and 21 are sent to the anti-phase synthesizer 25.
and is synthesized at output terminal 2 of this circuit. (5)
, (6) can be obtained as follows.

cog (wet+ψ)...1 (7) That is, according to this embodiment, the unnecessary waves seen in the process of FIG. 2 are removed, and a constant phase shift determined by the variable delay line is achieved with respect to the input signal COSWit. This means that the quantity ψ has been obtained.

FIG. 2 is a block diagram of another embodiment of the invention. Second
- In the figure, the signals at points 51 to 55 on the path and at the output terminal 2 are expressed simultaneously in FIG. 1 as shown in the following equations.

coswit fist cos (wit + ψ
)...(8) -cos wit -sin (wlt+f)...
・(9) cos(wit -w low 9) ・・・・・・(
10) -cos(wit-wit-ψ) -cos w
lt...(11) -cos(with-wl t-91) -sin
wl t-cos (wit-ψ) ... so + (1
3) In the end, equation (13) is obtained at the output terminal 2. Although this equation has a different sign from equation (7), it is clear that the same effect can be obtained as a phase shifter.

(Effects of the Invention) As explained above, according to the present invention, the phase difference between the input signal and the output signal does not depend on the input signal frequency, and no bandpass filter is used. It has the advantage of achieving a wide band and not generating group delay characteristics.

[Brief explanation of drawings]

1 and 2 are block diagrams of first and second embodiments of the present invention, and FIGS. 3 and 4 are block diagrams of two examples of conventional phase shifters. In the figure, 1...input terminal, 2...output terminal, 11...90 hybrid, 12, 13.18-21...frequency converter, 14, 15...Band filter, 16.
...Local oscillation source, 17...Variable delay line, 22゜24.26, 27...90 distributor, 2
3... In-phase (e) combiner, 25... Out-of-phase (180') combiner, 28... 0 distributor, 2
9.30...90' combiner, 30...
180 distributor, 41-45.51-55...4
This is a point on route No. 3. Orange /1gJ Sen 2 Figure 3 Drunk Leather 4 Field

Claims (1)

[Claims] a first branching means for branching an input signal into two; first and second frequency converting means for frequency-converting the branched outputs by respective first frequency signals;
and a first combining means for suppressing and combining one sideband of the output of the second frequency converting means; a second branching means for branching the output of the first combining means into two; third and fourth frequency converting means for frequency converting each output of the branching means with a second frequency signal, and synthesizing each output of the third and fourth frequency converting means to extract an input signal component. a second combining means, a local oscillator that generates a predetermined frequency signal, and a variable delay line that provides a variable delay corresponding to a predetermined phase shift amount to the output of the local oscillator;
and means for supplying the output of the variable delay line or the output of the local oscillator to each of the frequency converting means as each of the first and second frequency signals.