RU2568771C1 - Phase shifter of triangular waveform - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: phase shifter of triangular waveform contains two pulse shapers, the logic circuit, two switches, two adders and the amplitude sensor.

EFFECT: formation of triangular waveform shifted by 90 degrees with reference to its input triangular waveform, the frequency and amplitude of which can be changed in a wide range.

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Description

The invention relates to the field of radio engineering and computer engineering and can be used in radar, in voltage-time interval converters, pulse-width modulators, time delay devices, etc.

A device [1] is known, which contains a phase-shifting element, a voltage divider (modulo and sign of the transmission coefficient), a first, second and third adders, first and second phase detectors, first and second integrators and a controlled amplifier, while the input of the device is connected to the input phase-shifting element, the first input of the controlled voltage divider, the first inputs of the second and third adders and the first phase detector, and the outputs of the phase-shifting element and the controlled voltage divider are connected to the inputs the first adder, the output of which is connected to the inputs of the first phase detector and the controlled amplifier, the output of which is connected to the output of the device and the second inputs of the second and third adders, the outputs of which are connected to the inputs of the second phase detector, the output of which is connected through the second integrator to the control input of the controlled amplifier, moreover, the first integrator is connected between the output of the first phase detector and the second input of the controlled voltage divider.

When harmonic oscillations are applied to the input, harmonic oscillations are also generated at the device output, but shifted by 90 electrical degrees relative to the input ones. The device cannot work with input signals whose form differs from harmonic ones.

A device [2] is known that contains input and output operational amplifiers, a diode limiter, first, second, third and fourth resistors, an input bus and a control bus that is connected to the inverting input of the first operational amplifier, the non-inverting input of which is connected to the input bus, between which and a non-inverting input of the second operational amplifier includes a first resistor, a second resistor is connected between the control bus of the inverting input of the second operational amplifier, the output of which is connected to the output second bus, said third resistor connected between the output of the diode limiter and the non-inverting input of the second operational amplifier, between the output and the inverting input of which a fourth resistor is included.

The disadvantage of this device is the low accuracy of the installation of a fixed phase shift due to possible changes in the amplitude of the voltage of a triangular shape and the magnitude of the control voltage.

The closest device to the claimed invention in terms of essential features is the signal frequency doubler [3] adopted as a prototype, comprising a control voltage source, first and second pulse shapers made of comparators, a logic circuit, first and second switches, an adder and an integrator included between the output of the first switch and the first output bus, while the output of the integrator is connected to the inputs of the first and second pulse shapers and the second input of the adder, to the output of which the first input of the second switch is connected, the second input of which is connected to the output of the logic circuit, the first input of which is connected to the first input of the adder, the second inputs of the first switch and the logic circuit connected to the output of the second shaper, the second output bus connected to the output of the second switch, and the first the input of the first switch is connected to the output of the control voltage source.

The device operates in self-oscillating mode and generates triangular-shaped signals at its outputs, shifted by 90 electrical degrees relative to each other.

The problem to which the invention is directed is to expand the functionality of the device by receiving at its output a triangular-shaped signal shifted 90 degrees from the input triangular-shaped signal, the frequency and amplitude of which can vary widely.

The technical result achieved by the implementation of the invention is to expand the functionality of the device by receiving at its output a triangular-shaped signal shifted 90 degrees from the input triangular-shaped signal, the frequency and amplitude of which can vary widely.

The specified technical result during the implementation of the invention is achieved by the fact that in the phase shifter of the signal is a triangular shape, containing the first and second pulse shapers, a logic circuit, the first and second switches and an adder, the output of which is connected to the second input of the second switch, the output of which is connected to the output of the phase shifter of the signal forms, the input bus of which is connected to the inputs of the first and second pulse shapers and the second input of the adder, while to the output of the first pulse shaper under the first input of the logic circuit is connected, the second input of which is connected to the output of the second pulse shaper and the second input of the first switch; an amplitude sensor and a second adder are additionally introduced, the first input of which is connected to the output of the logic circuit and the second input of the amplitude sensor, the first input of which is connected to the input bus the phase shifter of the signal is triangular in shape, while the output of the amplitude sensor is connected to the first input of the first switch, the output of which is connected to the first input of the adder, and the first input of the second to The switch is connected to the output of the second adder, the second input of which is connected to the voltage reference bus.

The amplitude sensor can be made of a module calculator, a sampling-storage device and a single-vibrator, the input of which is connected to the second input of the amplitude sensor, the first input of which is connected to the input of the module calculator, to the output of which the first input of the sampling-storage device, the second input of which is connected to the output of the one-shot, while the output of the sample-storage device is connected to the output of the amplitude sensor.

The first pulse shaper may be made of an operational amplifier, a third adder, a two-anode zener diode and a capacitor connected between a common bus and an inverting input of an operational amplifier, a non-inverting input of which is connected to the first input of the third adder, the second input of which is connected to the output of the operational amplifier, while the two-anode a zener diode is connected between the inverting input and the output of the operational amplifier, and the output of the third adder is connected to the output of the first impu sov, whose input is connected to the first input of the third adder.

The second pulse shaper may be made of an amplifier-limiter, the logic circuit may be made of an exclusive OR circuit, and the first and second switches may be made of multipliers.

The analysis of the prior art by the applicant, including a search by patent and scientific and technical sources of information, allowed to establish that the applicant did not find an analogue characterized by features identical to all the essential features of the claimed invention. Therefore, the claimed invention meets the condition of "novelty."

The introduction of the amplitude sensor and the second adder into the proposed device, as well as the organization of new connections between the functional elements, made it possible to expand the device’s functionality by receiving at its output a triangular-shaped signal shifted by 90 electrical degrees with respect to the triangular-shaped input, the frequency and amplitude of which can vary widely.

The invention is illustrated by the structural diagram of the phase shifter of the signal of a triangular shape (Fig. 1) and graphs (Fig. 2, Fig. 3), explaining the principle of operation of the phase shifter of a signal of a triangular shape.

The phase shifter of the triangular signal (Fig. 1) contains the first 1 and second 2 pulse shapers, logic 3, the first 4 and second 5 switches, an adder 6, an amplitude sensor 7 and a second adder 8, to the output of which the first input of the second switch 5 is connected, the output of which is connected to the output of a phase shifter of a triangular waveform, the input bus of which is connected to the second input of the adder 6, the first input of the amplitude sensor 7, the input of the first driver 1 and the input of the second driver 2, the output of which is connected to the second the first switch 4 and the second input of the logic circuit 3, the output of which is connected to the first input of the second adder 8 and the second input of the amplitude sensor 7, the output of which is connected to the first input of the first switch 4, the output of which is connected to the first input of the adder 6, the output of which is connected to the second input of the second switch 5, while the second input of the second adder 8 is connected to the voltage reference bus.

Amplitude sensor 7 can be made from a calculator of module 9, a sample-storage device 10 and a single-vibrator 11, the input of which is connected to the second input of the amplitude sensor 7, the first input of which is connected to the input of the calculator of module 9, to the output of which the first input of the sample-storage device is connected 10, the second input of which is connected to the output of the single-shot 11, while the output of the sample-storage device 10 is connected to the output of the amplitude sensor 7.

The first pulse shaper 1 can be made of an operational amplifier 12, a third adder 13, a two-anode zener diode 14, and a capacitor 15 connected between a common bus and an inverting input of an operational amplifier 12, the non-inverting input of which is connected to the first input of the third adder 13, the second input of which is connected to the output of the operational amplifier 12, while the two-anode zener diode 14 is connected between the inverting input and the output of the operational amplifier 12, and the output of the third adder 13 is connected to the output of the first pho pulse rider 1, the input of which is connected to the first input of the third adder 13.

The second pulse shaper 2 can be made of an amplifier-limiter, the logic circuit 3 can be made of the logic circuit EXCLUSIVE OR, and the first 4 and second 5 switches are made of multipliers.

The phase shifter of the triangular waveform operates as follows.

A periodic signal N ₁ (t) of a triangular shape (Fig. 2, a) with an amplitude value A fed to the input bus of the phase shifter is also fed to the input of the first pulse shaper 1 (Fig. 1) made of operational amplifier 12, adder 13, two-anode zener diode 14 and capacitor 15.

The gain (constant current) of the operational amplifier 12 can reach very large values (K ₀ ≥1 * 10 ⁶ ), so the corresponding voltages e ₁ (t) and e ₂ (t) present on the inverting and non-inverting inputs will be approximately equal , i.e., e ₁ (t) ≈ е ₂ (t). The non-inverting input of the operational amplifier 12 receives a signal N ₁ (t), therefore, almost the same signal will be present at the inverting input of the operational amplifier 12.

But for large values of K _{0, a} very small difference in the signals δ (t) = e ₂ (t) -e ₁ (t) is sufficient for the voltage at the output of amplifier 12 to very quickly reach the saturation voltage of operational amplifier 12.

Due to the fact that in the feedback circuit (between the output and the inverting input of the amplifier 12) a two-anode zener diode is connected, a bipolar rectangular signal U _Z (t) with limiting voltages U _0l and U ₀₂ is formed on it (Fig. _2a ) determined by the parameters of the two-anode zener diode 14.

In this case, at the output of the operational amplifier 12, a signal U (t) is generated (Fig. 2b), the values of which change stepwise at the moments corresponding to the maximum (extreme) values of the input signal N ₁ (t). Thus, the pulse shaper 1 is nothing more than an extremator, that is, a device that generates a signal with abruptly changing values at moments corresponding to the extreme values of the input signal of the extremator.

We assume that the stabilization voltages U ₀₁ and U _{02 of the} two-anode zener diode 14 are equal, that is, U ₀₁ = U ₀₂ = U ₀ , then the values of L ₁ and L ₂ (Fig. 2, b) of the generated signal U (t) will be equal

The levels L ₃ and L ₄ , to which there is an abrupt change in the signal U (t), are determined as follows

To find the analytical expressions of the signals N ₁ (t) and U (t) we use the general expression for the line y = kx + b passing through two points with coordinates (x ₁ , y ₁ ) and (x ₂ , y ₂ )

where x is the current value of the angle in radians.

At x = π, the signal U (t) abruptly changes its value (Fig. 2b) from the level L ₁ to the value L ₃ , and at x = 2π (x = 0) the signal values change to the level L ₄ .

Substituting in (3) the coordinates of the two boundary points [x ₁ = 0, y ₁ = -A; x ₂ = π, y ₂ = A], we obtain

Substituting in (3) the coordinates of the boundary points [x ₁ = 0, y ₁ = L ₄ ; x ₂ = π / 2, y ₂ = L ₁ ] for the signal U (t), we obtain

The output of the adder 13 is formed (Fig. 2, c) a signal

where k ₃₁ and k ₃₂ are the transfer coefficients of the adder 13, respectively, at the first and second inputs.

Substituting (4) and (5) into equation (6), we obtain

When k ₃₁ = k ₃₂ = k _3, expression (7) is simplified

For the second interval x∈ [π; 2π], the equations for signals N ₁ (t) and U (t) will take the following expressions

Substituting (8) and (9) into equation (6), we obtain

With the equality of the coefficients k ₃₁ = k ₃₂ = k ₃ we get

Analysis of (8) and (12) shows that in the first interval x∈ [0; π] the signal K ₁ (x) takes a constant value of positive polarity, independent of the current value of the angle x, and in the second interval x∈ [π; 2π], a constant signal of negative polarity is formed (Fig. 2, c).

, равных единице, необходимо выполнить условиеTo obtain normalized amplitude values

equal to unity, it is necessary to fulfill the condition

может быть получено при любых значениях напряжений двуханодного стабилитрона 14, при этом необходимо выполнить лишь одно условие, что k₃=1/U₀.It follows from (13) that the normalized value

can be obtained at any voltage values of the two-anode zener diode 14, and it is necessary to fulfill only one condition that k ₃ = 1 / U ₀ .

Thus, at the output of the adder 13, and consequently, at the output of the first pulse shaper 1, a rectangular bipolar signal K ₁ (t) is generated (Fig. 2, c), which is fed to the first input of the EXCLUSIVE OR circuit 3, to the second the input of which is supplied (Fig. 2, d) from the output of the second driver 2, a rectangular bipolar signal K ₂ (t).

The pulse shaper 2 can be performed, for example, from an amplifier-limiter, with normalized amplitude values equal to unity (Fig. 2, d).

At the output of the “EXCLUSIVE OR” logic circuit 3, a sequence of unipolar pulses F (t) with a normalized amplitude value equal to one is formed (Fig. 2e).

Amplitude sensor 7 is made of a calculator of module 9, a sample-storage device 10 and a single-vibrator 11. At the first input of amplitude sensor 7, signal N ₁ (t) is received (Fig. 1), and signal F (t) from the logic output is received at the second input EXCLUSIVE OR schemes 3.

The one-shot 11, which is part of the amplitude sensor 7, is triggered on the leading edge of the pulses F (t) received at its input. At the output of the single-vibrator, narrow gating pulses D (t) are formed (Fig. 2f), which are fed to the second input of the sampling-storage device 10, the first input of which (Fig. 2g) receives the signal M (t )

The strobe pulses D (t) are input to the sample-storage device 10 at time points corresponding to the maximum values of the signal M (t). Thus, at the output of the sample-storage device 10, and hence at the output of the amplitude sensor 7, a constant voltage E _{m is formed} , the value of which is exactly equal to the amplitude value A of the input signal N ₁ (t), that is, E _m = A.

Since the interrogation of the sample-storage device 10 occurs twice (Fig. 2f) for the period of the input signal N ₁ (t), the amplitude sensor 7 has a high speed and can operate in the low and infra-low frequencies of the input signals, which is its advantage.

The formation of a triangular waveform N ₂ (t), shifted by 90 electrical degrees with respect to the input signal N ₁ (t), occurs (Fig. 3) as follows.

The amplitude A of the input signal N ₁ (t) can vary in a wide range (Fig. 3, a), the amplitude of a rectangular bipolar signal K ₂ (t) is always equal to the normalized value (Fig. 3, b), so switch 4, made for example, from the multiplier, the signal R (t) is generated, the amplitude of which will always be equal to (Fig. 3, c) the amplitude of the input signal N ₁ (t), that is, E _m = A.

The inputs of the first adder 6 receives signals N ₁ (t) and R (t), as a result of the summation of which at its output a signal is generated (Fig. 3, d)

where k ₁₁ and k ₁₂ are the transfer coefficients of the adder 6, respectively, at the first and second inputs.

The second adder 8 acts as a signal level Converter. The first input of the adder 8 receives a sequence of unipolar rectangular pulses (Fig. 2, e), and the second input is a constant reference voltage E _{0 of} negative polarity. The output of the adder 8 is formed (Fig. 3, d) signal

where k ₂₁ and k ₂₂ are the transfer coefficients of the adder 8, respectively, at the first and second inputs.

When k _2l = 2, k ₂₂ = 1 and E ₀ = -1

a rectangular bipolar signal S ₁ (t) with normalized amplitude values equal to unity will be generated at the output of the signal level converter.

Using a switch 5, which can be made, for example, from a multiplier, a signal N ₂ (t) = S ₁ (t) · S ₂ (t) is formed (Fig. 3f), phase-shifted by 90 electrical degrees relative to the input signal N ₁ (t).

Using the present invention will expand the functionality of the device by receiving at its output a signal of a triangular shape, shifted relative to the input signal of a triangular shape by 90 electrical degrees, the frequency and amplitude of which can vary widely.

Information sources

1. A.S. USSR No. 1800006, G01R 25/04. Parkhomenko N.G., Botashev B.M. 90 ° phase shift device 01.24.1991, publ. 03/07/1993. Bull. No. 9.

2. A.S. USSR No. 822326, H03K 4/06. Averbukh V.D. Device for controlling the phase of the voltage of a triangular shape, decl. 07/29/1977, publ. 04/15/1981. Bull. Number 14.

3. A.S. USSR No. 1480087, Н03В 27/00. Begalov V.A., Talankin A.A., Chernykh I.V. Controlled two-phase triangular oscillator 10.28.1987, publ. 05/15/1989. Bull. No. 18 (prototype).

Claims (4)

1. The phase shifter of the signal of a triangular shape, containing the first and second pulse shapers, a logic circuit, the first and second switches and an adder, the output of which is connected to the second input of the second switch, the output of which is connected to the output of the phase shifter of the signal of a triangular shape, the input bus of which is connected to the inputs of the first and the second pulse shaper and the second input of the adder, while the output of the first pulse shaper is connected to the first input of the logic circuit, the second input of which is connected to the output of the second pulse generator and the second input of the first switch, characterized in that it additionally includes an amplitude sensor and a second adder, the first input of which is connected to the output of the logic circuit and the second input of the amplitude sensor, the first input of which is connected to the input bus of the phase shifter of the signal of triangular shape, while the output of the amplitude sensor is connected to the first input of the first switch, the output of which is connected to the first input of the adder, and the first input of the second switch is connected to the output of the second adder, the second the input of which is connected to the voltage reference bus. 2. The phase shifter of the triangular waveform according to claim 1, characterized in that the amplitude sensor is made of a module calculator, a sample-storage device and a single-vibrator, the input of which is connected to the second input of the amplitude sensor, the first input of which is connected to the input of the module calculator, to the output of which the first input of the sample-storage device is connected, the second input of which is connected to the output of a single-shot, while the output of the sample-storage device is connected to the output of the amplitude sensor. 3. The phase shifter of the triangular waveform according to claim 1, characterized in that the first pulse shaper is made of an operational amplifier, a third adder, a two-anode zener diode and a capacitor connected between a common bus and an inverting input of an operational amplifier, the non-inverting input of which is connected to the first input of the third adder , the second input of which is connected to the output of the operational amplifier, while the two-anode zener diode is connected between the inverting input and the output of the operational amplifier, and the output is third first adder connected to the output of the first pulse generator having an input coupled to a first input of the third adder. 4. The tri-phase signal phase shifter according to claim 1, characterized in that the second pulse shaper is made of an amplifier-limiter, the logic circuit is made of an EXCLUSIVE OR logic circuit, and the first and second switches are made of multipliers.

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