JPH03165603A - Amplitude phase control circuit for high frequency signal - Google Patents

Abstract

PURPOSE:To control the phase of a high frequency signal to a prescribed value and to control the amplitude without giving effect on the phase by dividing an input high frequency signal equally and controlling the phase of both the signals independently so that the synthesized output signal resulting from both the signals has a desired phase. CONSTITUTION:An inputted high frequency signal is divided equally into two by a power distributor 1, they are inputted respectively to phase shifters 2, 3, where they are subject to phase control and they are synthesized by a power synthesizer 4, and the phase control is implemented in a way that the output high frequency signal of the power synthesizer 4 has a desired amplitude and phase. That is, the information of the amplitude and phase to be provided to the output high frequency signal of the power synthesizer 4 is fed externally to a decoder 6 as a control signal, the decoder 6 forms the amplitude control variable and the phase control variable upon the receipt of the control signal and they are outputted to a lag phase quantity generating circuit 8 and a lead phase quantity generating circuit 7. The circuits 7, 8 control the output of the phase shifters 2, 3 to control the phase and amplitude of the output high frequency signal expressed in the vector sum. Thus, the amplitude is controlled without giving effect onto the phase of the output high frequency signal.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to an amplitude/phase control circuit for high frequency signals.

(Prior art) As a circuit for controlling the amplitude and phase of a high frequency signal,
Conventionally, for example, as shown in FIG. 5, a phase shifter 9 and a variable attenuator 11 are provided before and after the power amplifier 1G, or a
As shown in the figure, a circuit in which a phase shifter 9 and a variable attenuator 11 are provided in series before a power amplifier 10, the amplitude is controlled by the variable attenuator 11, and the phase is controlled by the phase shifter 9. It has been known.

(Problems to be Solved by the Invention) However, when controlling the amplitude and phase of a high frequency signal using a variable attenuator and a phase shifter, there are the following problems.

First, when the amplitude is controlled by a variable attenuator, the insertion phase of the variable attenuator changes, so even if the phase shifter is controlled so that the output high-frequency signal has the required phase, each time the amplitude is changed It is necessary to further correct the change in the intrusion phase of the variable attenuator, which complicates control.

Furthermore, a class 0 power amplifier is often used as an amplifier for high frequency signals. In this case, if the amplitude is controlled at the input stage of the amplifier, the amplitude variable range cannot be widened and the phase of the output signal changes, so it is necessary to control the amplitude at the output stage.

However, the PIN diode used to electronically vary the amplitude of a high-frequency signal at high speed has low power resistance, so it cannot be used as a variable attenuator in the output stage of a class C power amplifier. Therefore, it is desired to develop a variable attenuator that can control the amplitude at high speed in a high-power output stage.

The present invention was made in view of these problems, and its purpose is to enable amplitude control without affecting the phase, and
An object of the present invention is to provide an amplitude/phase control circuit for a high frequency signal that can control the amplitude and phase of even a high power high frequency signal.

(Means for resolving the order of assignment) In order to achieve the above object, the high frequency signal amplitude/phase control circuit of the present invention has the following configuration.

That is, the high-frequency signal amplitude/phase control circuit of the present invention includes a power divider that divides an input high-frequency signal into two equal parts and outputs the same; two phase shifters controlled according to control signals;
a power combiner that combines the outputs of the two phase shifters;
a decoder that receives an externally applied control signal that indicates the amplitude and phase that the output high-frequency signal of the power combiner should have, and outputs an amplitude control value and a phase control value; In response to the phase control value, determine a delay phase shift amount that gives a suitably delayed phase from the phase of the output high-frequency signal, and send the phase shift control signal formed based on the delay phase shift amount to one of the two phase shifters. a delayed phase shift amount generating circuit to output, and the phase shift control that determines an advance phase shift amount that is the same as the phase shift amount to give a phase that is advanced by an appropriate amount from the phase of the output high frequency signal, and is formed based on the same amount of advance phase shift amount. The present invention is characterized by comprising: an advanced phase shift amount generation circuit that outputs a signal to the other of the two phase shifters;

(Function) Next, the function of the high frequency signal amplitude/phase control circuit of the present invention configured as described above will be explained.

The input high-frequency signal is divided into two parts by a power divider, each input to a corresponding phase shifter, which receives phase shift control, and is combined by a power combiner. This is done so that the high frequency signal has the desired amplitude and phase.

That is, the amplitude and phase information that the output high-frequency signal of the power combiner should have is supplied to the decoder from the outside as a control signal. Upon receiving this control signal, the decoder forms an amplitude control value and a phase control value, and outputs them to the delay phase shift amount generation circuit and the advance phase shift amount generation circuit.

Therefore, in the delayed phase shift amount generation circuit, the amount of phase shift that gives the most delayed phase from the phase of the output high frequency signal is determined, and the amount of phase shift between the output high frequency signal and the input high frequency signal is added to the phase shift amount to obtain a predetermined phase shift. A control signal is formed and applied to one of the two phase shifters.

In addition, in the leading phase shift IIklF and Ikuchi path, the leading phase shift amount which is the same as the delay phase shift amount is determined, and the phase shift amount between the output high frequency signal and the input high frequency signal is subtracted from the leading phase shift amount. A predetermined phase shift control signal is formed and applied to the other phase shifter.

Since the output high frequency signal is given by the vector sum of the outputs of the two phase shifters, the phase and amplitude of the output high frequency signal are controlled. At this time, each phase shifter controls the phase of the corresponding input signal by a phase shift amount φ that is equal to the phase of the output high-frequency signal. If the amplitude of the input high-frequency signal is IXI, it is controlled independently of the phase of the input/output high-frequency signal of each phase shifter.

Thus, according to the present invention, it is possible to control the input high frequency signal to a predetermined phase and output it, and also to control the amplitude without affecting the phase of the output high frequency signal.

(Example) Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows a first embodiment circuit of the present invention. The high frequency signal amplitude/phase control circuit according to the first embodiment includes a T-type power divider 1, a phase shifter 2, a phase shifter 3, a T-type power divider 1, a phase shifter 2, a phase shifter 3, It basically consists of a power combiner 4, an isolator 5, a decoder 6, a leading phase shift amount generation circuit 7, and a lag phase shift amount generation circuit 8.

The high frequency signal input to the T-type power divider 1 is divided into two equal parts and input to the corresponding phase shifters 2 and 3, respectively. The phase shifter 2 receives a phase shift control signal from the leading phase shift amount generation circuit 7, and the phase shifter 3 receives a phase shift control signal from the lag phase shift amount generation circuit 8, and performs the required phase shift control on each input signal. do. The outputs of phase shifters 2 and 3 are input to a T-type power combiner 4 via an isolator 5 and are combined.

That is, the T-type power combiner 4 outputs a high frequency signal whose amplitude and phase are controlled. Note that the isolator 5 is a circuit that absorbs signals reflected without being combined by the T-type power combiner 4.

On the other hand, the decoder 6 receives a control signal from the outside that indicates the amplitude and phase that the output high-frequency signal of the T-type power combiner 4 should have, so it reads the amplitude control value and the phase control value, advances them, and shifts the phase. It is output to the amount generation circuit 7 and the delay phase shift amount generation circuit 8.

Then, a leading phase shift amount generation circuit 7 and a lag phase shift amount generation circuit 8
generates the phase shift control signal based on the input amplitude control value and phase control value.

A detailed explanation will be given below with reference to FIG. FIG. 2 is a vector diagram showing the relationship between the amplitude and phase of each signal. Vector A is the input high frequency signal (amplitude IA
I), based on the phase of this input high frequency signal,
A vector C of the output high frequency signal (amplitude CI) of the T-type power combiner 4 is shown separated from it by a phase φ. This vector C is the vector sum of vectors B and B'.

That is, vector B is the output signal of phase shifter 2 (amplitude I B
+ = "), vector B' is the output signal (amplitude IB', =;) of phase shifter 3. In the illustrated example, vector B is +φ2 ahead of vector C, and vector B' is - is the delayed phase of φ2, and as a result, the amplitude IC
This shows that a vector C of I is formed. In addition,
The amplitude 1cI is C1=2・IBI・COSφ2,
However, transmission loss is ignored.

Now, the amplitude control value that the decoder 6 reads from the externally applied control signal is IcI/IAI, and the phase control value is φ!
It is. This is supplied to a leading phase shift amount generation circuit 7 and a lag phase shift amount generation circuit 8.

The leading phase shift amount generating circuit 7 and the lagging phase shift amount generating circuit 8 calculate the phase shift amount φ2 based on the amplitude control value 1cI/IAI, taking into consideration the loss of the transmission line. Then, the advanced phase shift amount generation circuit 7 adds the phase φ1 to the phase shift amount φ2, and provides the result to the phase shifter 2 as a phase shift control signal. On the other hand, in the delayed phase shift generation circuit 8, the phase φ! The phase shift amount φ2 is subtracted from the phase shift amount φ2, and the result is given to the phase shifter 3 as a phase shift control signal.

As a result, phase shifter 2 shifts the input signal to φ1+φ2 and outputs it, and phase shifter 3 outputs the input signal to φ1+φ2.
Since the phase is shifted to -φ2 and output, the T-type power combiner 4 outputs the required amplitude 1cI and phase φ1 corresponding to the vector C.
A high frequency signal that is controlled to be obtained. At this time, by changing only φ2 without changing φ1, the amplitude value can be freely varied without changing the phase of the composite output high-frequency signal.

Note that the phase shifters 2 and 3 are composed of PIN diodes, and since the PIN diodes in this case operate as switches, their power durability is considerably high. That is,
The amplitude and phase can be controlled at the output stage of the class C power amplifier. Therefore, it can be applied to an array antenna as shown in FIG.

In FIG. 3, the antenna module 15 includes the first
The power divider 1 is mainly based on the example circuit, and includes a power amplifier lO provided on the input side of the T-type power divider 1, and an element antenna I3 provided on the output side of the T-type power combiner 4.
2 distributes and outputs the high frequency signal from the signal generator 14 to each power amplifier 10 in a plurality of antenna modules 15. Further, the beam scanning control signal from the beam controller 16 is transmitted to each decoder 6 in the plurality of antenna modules 15.
is supplied to

This allows each element antenna! The amplitude and phase distribution of electromagnetic waves radiated from 3 are controlled.

Next, FIG. 4 shows a second embodiment circuit. This second embodiment circuit uses a Wilkinson type power divider 17 as a power divider that equally divides the power into two, and functions as a power combining circuit and a reflected wave absorption circuit. A hybrid coupler 18 equipped with a terminating resistor 20 is used to perform both functions, and a correction is performed to compensate for a difference in phase between two input signals in the hybrid coupler 18 due to a transmission path difference to the output end. A phase shift amount generation circuit 19 is added.

Since the operation is similar to that of the first embodiment, its explanation will be omitted.

(Effects of the Invention) As explained above, according to the high frequency signal amplitude/phase tAfR circuit of the present invention, the input high frequency signal is divided into two equal parts, and the combined output signal of both signals is shifted so that the combined output signal has the desired phase. A phase amount and a delayed phase shift amount centered on that phase are given to one signal, and a leading phase shift amount of the same amount as the delayed phase shift amount is given to the other signal, and both signals are combined, and Since these phase shift amounts can be controlled independently, it is possible to control the high frequency signal to a desired phase, and at the same time, it is possible to control the amplitude without changing the controlled phase.

In addition, since the phase shifter has high power resistance, it can be used on the output side of circuits where amplitude control is difficult, such as class C power amplifiers, and high-output amplitude control can be performed at high speed. .

[Brief explanation of the drawing]

Fig. 1 is a block diagram of the configuration of a first embodiment circuit which is a high frequency signal amplitude/phase M control circuit according to the present invention, Fig. 2 is a diagram of the relationship between the phase and amplitude of each signal (operation explanatory diagram), and Fig. 3 4 is a configuration block diagram of an array antenna as an application example of the first embodiment circuit, FIG. 4 is a configuration block diagram of a second embodiment circuit of the present invention, and FIGS. 5 and 6 are configuration block diagrams of a conventional circuit. It is. 1...T-type power divider, 2,3...
Phase shifter, 4...T-type power combiner, 5-...
...Isolator, 6...Decoder, 7...
... Leading phase shift amount generation circuit, 8... Lagging phase shift amount generation circuit, 9... Phase shifter, 12...
・Power divider, 13...element antenna,! 4
... Signal generator, 15 ... Antenna module, 16 ... Beam controller, 17.
...Wilkinson type power divider, l...
...Hybrid coupler, 19...Correction phase shift generation circuit, 20...Terminal resistor.

Claims (1)

[Claims] A power divider that equally divides an input high frequency signal and outputs it; Two phase shifters that control the phase of each of the two outputs of this power divider according to a corresponding phase shift control signal; A power combiner that combines the outputs of the phase shifters; Amplitude control value and phase control in response to a control signal given from the outside that indicates the amplitude and phase that the output high frequency signal of the power combiner should have. a decoder that receives the amplitude control value and the phase control value, determines a delay phase shift amount that gives a phase delayed by an appropriate amount from the phase of the output high frequency signal, and forms the shift based on the delay phase shift amount; a delay phase shift generation circuit that outputs a phase control signal to one of the two phase shifters; and a delay phase shift generation circuit that outputs a phase control signal to one of the two phase shifters; An amplitude/phase control circuit for a high frequency signal, comprising: an advanced phase shift amount generation circuit that determines a phase amount and outputs the phase shift control signal formed based on the phase shift amount to the other of the two phase shifters; .