RU2534938C1 - Multifrequency functional generator - Google Patents

Abstract

FIELD: radio, communication.

SUBSTANCE: multifrequency functional generator comprises a first and second calculators of the module, a summing unit, a frequency synthesizer, and a phase modulator made of the control pulse generator and the commutation switch, the source of quadrature signals, the inverter, the adder and the bipolar rectangular pulse generator.

EFFECT: enhanced functional capabilities through formation of harmonic signals of several frequencies and signals of different forms of the same frequency and improvement of the metrological characteristics of the generated signals.

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Description

The invention relates to radio engineering and communication and can be used to form a frequency grid in communication equipment, measuring and computer technology, as well as to generate quadrature harmonic signals of several frequencies and signals of various shapes of the same frequency.

A device [1] is known, which contains a reference generator, a control unit, two memory registers, two multi-frequency generators, two keys, a load, a selector, two pulse edge allocation blocks, a counting trigger, and two delay lines. At a single output, signals of different frequencies alternately generated by the first and second multi-frequency generators are alternately formed. The device is not multifunctional, since only one form of signals is generated at its output.

A device [2] is known, which comprises a reference generator, a high-frequency generation unit, two frequency multipliers, and n-1 PLLs, each of which consists of a controlled oscillator, mixer, phase detector, and low-pass filter connected to a ring, when The output of the high-frequency generating unit and the outputs of the controlled generators are the outputs of the device. Each harmonic of the frequency grid corresponds to a separate PLL, which complicates the device, in which there is a complex algorithm for the interaction of functional devices, complicating the setup and tuning procedure and requiring highly qualified tuner [3]. The device generates n frequencies simultaneously at its outputs, but does not generate signals of various shapes, that is, it is not multifunctional.

A device [4] is known that contains a master oscillator, Schmitt trigger, integrator and adder, the first and second inputs of which are connected to the outputs of the master oscillator and Schmitt trigger, the input of which is connected to the output of the integrator connected between the output of the adder and the output of the functional generator. The device generates signals of various shapes, except for a sinusoidal, and only one frequency.

The closest device to the claimed invention in terms of essential features is a multi-frequency functional generator [5] adopted for the prototype, containing the first and second module calculators made of half-wave rectifiers, a summing unit made of the first subtractor and adder, a frequency synthesizer made of the first and the second multipliers, the quadrator and the second subtractor, as well as a phase modulator made of a control pulse shaper (amplitude comparator) and switch, the first input of the multi-frequency functional generator connected to the input of the first calculator module and the first input of the frequency synthesizer, the first and second outputs of which are connected to the corresponding inputs of the phase modulator, the output of which is connected to the third input of the summing unit, the output of which is connected to the output of the multi-frequency functional generator the second input of which is connected to the second input of the frequency synthesizer and the input of the second calculator module, the output of which is connected to the second input unit, the first input of which is connected to the output of the first calculator module.

Two harmonic sinusoidal signals are formed in the device, the frequency of one of them is two times, and the frequency of the second is four times higher than the frequency of the input quadrature signals, as well as a “quasilinear” signal of a triangular shape with a relatively low degree of linearity. In addition, the device does not have a rectangular pulse shaper or rectangular bipolar pulses, the necessary attributes of a full-fledged functional generator.

The task to which the invention is directed is to expand the functionality and improve the metrological characteristics of the generated signals.

The specified technical result in the implementation of the invention is achieved by the fact that in a multi-frequency functional generator containing the first and second module calculators, a summing unit, a frequency synthesizer and a phase modulator made of a control pulse shaper and a switch, the output of which is connected to the output of the phase modulator, the second input of which connected to the second input of the switch, the first input of which is connected to the output of the driver of the control pulses, the input of which is connected to the first input of the phase the modulator, the third input of the summing unit is connected to the output of the phase modulator, the output and the first input of which are connected respectively to the first output of the multi-frequency functional generator and to the output of the first computer of the module, the input of which is connected to the first input of the frequency synthesizer, the second input of which is connected to the input of the second module, the third output of the multi-frequency functional generator is connected to the first input of the phase modulator and to the first output of the frequency synthesizer, the second input of which connected to the fourth output of the multi-frequency functional generator, the source of quadrature signals, an inverter, an adder and a shaper of bipolar rectangular pulses, connected between the output of the summing unit and the second output of the multi-frequency functional generator, the fifth, sixth and seventh outputs of which are connected to the third, fourth and fifth respectively the outputs of the frequency synthesizer, the first and second inputs of which are connected to the corresponding outputs of the source of quadrature signals, the control the input of which is connected to the control bus of the multi-frequency functional generator, the eighth and ninth outputs of which are connected respectively to the first and second outputs of the quadrature signal source, while the inverter is connected between the output of the second module calculator and the second input of the summing unit, and the second and third outputs of the frequency synthesizer are connected, respectively with the first and second inputs of the adder, the output of which is connected to the second input of the phase modulator.

At the same time, in the phase modulator, the control pulse generator can be made of an amplifier-limiter, and the switch can be made of an analog multiplier.

The frequency synthesizer can be made of the first, second and third amplifiers, the first, second and third multipliers, the first, second, third and fourth quadrators, the first and second subtracters, the first amplifier being connected between the first input of the frequency synthesizer and the first input of the first multiplier, a second amplifier is connected between the output of the first multiplier and the first input of the second multiplier, between the output of which and the first input of the third multiplier a third amplifier is connected, between the first input of the frequency synthesizer and the first input of the first subtractor includes the first quadrator, the second quadrator is connected between the second input of the frequency synthesizer and the second input of the first subtractor, between the output of which and the second input of the second subtractor the fourth quadrator is turned on, the third quadrator is connected between the output of the first multiplier and the first input of the second subtractor, the output of which is connected with the second input of the third multiplier, the input of the second multiplier is connected to the output of the first subtracter, and the second input of the first multiplier is connected to the second input of synt congestion frequency, the first, second and third outputs are connected respectively to the outputs of the first, second and third multipliers, fourth and fifth outputs of the frequency synthesizer connected to the outputs of the first and second subtractors.

The analysis of the prior art by the applicant, including a search by patent and scientific and technical sources of information, established 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."

Introduction to the proposed multi-frequency functional generator of a quadrature signal source, an inverter, an adder and a shaper of bipolar rectangular pulses, the implementation of a frequency synthesizer from the first, second and third amplifiers, the first, second and third multipliers, the first, second, third and fourth quadrators, the first and second subtractors The implementation of a phase modulator from a control pulse generator and a switch, as well as the organization of new connections between functional elements, allowed expand the functionality of the device, as well as improve the metrological characteristics of the generated signals.

The invention is illustrated by the structural diagram of a multi-frequency functional generator (figure 1), the structural diagram of a frequency synthesizer (figure 2) and graphs (figure 3 - figure 6) explaining the principle of operation of a multi-frequency functional generator.

The multi-frequency functional generator contains the first 1 and second 2 calculators of the module, the summing unit 3, the frequency synthesizer 4, the phase modulator 5, made of a control pulse shaper 6 and a switch 7, a quadrature signal source 8, an inverter 9, an adder 10, and a bipolar rectangular pulse shaper 11 connected between the output of the summing block 3 and the second output of the multi-frequency functional generator, the control bus 12 of which is connected to the control input of the source of quadrature signals 8, the first output which is connected to the input of the first calculator of module 1, the first input of the frequency synthesizer 4 and the eighth output of the multi-frequency functional generator, the second output of the quadrature signal source 8 is connected to the input of the second calculator of module 2, the second input of the frequency synthesizer 4 and the ninth output of the multi-frequency functional generator, third, the fourth, fifth, sixth and seventh outputs of which are connected respectively to the first, second, third, fourth and fifth outputs of the frequency synthesizer 4, to the first output of which the first input of the phase modulator 5, the second input of which is connected to the output of the adder 10, the first and second inputs of which are connected respectively to the second and third outputs of the frequency synthesizer 4, the first input of the summing unit 3, the third input and the output of which is connected respectively to the output of the phase modulator 5 and to the first output of the multi-frequency functional generator, and between the output of the second computer of module 2 and the second input of the summing unit 3, an inverter 9 is connected, a control pulse shaper 6 is connected between the first input of the phase modulator 5 and the first input of the switch 7, the output of which is connected to the output of the phase modulator 5, the second input of which is connected to the second input of the switch 7.

The driver pulse shaper 6 in the phase modulator 5 is made of an amplifier-limiter, and the switch 7 is made of an analog multiplier.

Frequency synthesizer 4 is made of the first 13, second 14 and third 15 amplifiers, the first 16, second 17 and third 18 multipliers, the first 19, second 20, third 21 and fourth 22 quadrants, the first 23 and second 24 subtracters, while the first amplifier 13 is connected between the first input of synthesizer 4 and the first input of the first multiplier 16, the second amplifier 14 is connected between the output of the first multiplier 16 and the first input of the second multiplier 17, between the output of which and the first input of the third multiplier 18 a third amplifier 15 is connected, between the first synthesis input torus 4 and the first input of the first subtractor 23 includes the first quadrator 19, the second quadrator 20 is connected between the second input of the frequency synthesizer 4 and the second input of the first subtractor 23, between the output of which and the second input of the second subtractor 24 the fourth quadrator 22 is connected, the third quadrator 21 is connected between the output the first multiplier 16 and the first input of the second subtractor 24, the output of which is connected to the second input of the third multiplier 18, the input of the second multiplier 17 is connected to the output of the first subtractor 23, and the second input of the first multiplier 16 oedinen to a second input of frequency synthesizer 4, a first, second and third outputs are connected respectively to the outputs of the first 16, second 17 and third multipliers 18, fourth and fifth outputs of the frequency synthesizer 4, respectively connected to the outputs of the first 23 and second subtractors 24.

Multi-frequency functional generator operates as follows.

When applying the control voltage E _y to the input of the source of quadrature signals 8 at its outputs after the end of the transient process, harmonic signals are set, shifted relative to each other by 90 el hail.

where A is the amplitude and ω ₀ is the circular frequency of the signals V ₁ (t) and V ₂ (t) associated with the cyclic frequency f _{0 by the} known relation ω ₀ = 2πf ₀ .

The calculators of the modules 1 and 2 provide (Fig.3) receiving the signal modules V ₁ (t) and V ₂ (t)

The second input of adder 3 receives a signal M ₁ (t), and its third input receives an inverted signal M ₃ (t) = - M ₂ (t).

As a result of summing the signals M ₁ (t) and M ₃ (t), a signal is generated (Fig. 3)

S _sint (t) = k ₁ M ₁ (t) -k ₂ M ₃ (t) = k ₁ mod [V ₁ (t)] - k ₂ mod [V ₂ (t)], (3)

where k ₁ and k ₂ are the transmission coefficients of the summing block 3 at the first and second inputs, respectively.

When k ₁ = k ₂ = 1, the amplitude of the signal S _sint (f) will be equal to the amplitude value A of the signals V ₁ (t) and V ₂ (t).

In Fig. 3, the graphs are plotted for the normalized value A ^* = 1. The value of the current angle x = ω ₀ t is expressed in radians. The period T _{0 of the} fundamental harmonic is determined by the frequency ω ₀

T ₀ = 1 / f ₀ = 2π / ω ₀ ,

therefore, the fundamental frequency ω _{1 of the} synthesized triangular waveform S _sint (t) is equal to twice the frequency ω _{0 of the} quadrature signals V ₁ (t) and V ₂ (t)

ω ₁ = 2ω ₀ (or f ₁ = 2f ₀ ).

In the areas of “forward travel” (from zero to π / 2) and “reverse travel” (from π / 2 to π), the signal S _sint (t) has S-shaped characteristics, that is, it is “quasilinear”.

To assess the nonlinearity of the synthesized signal S _sint (t), we calculate the error value e ₀ (t), i.e., the deviation of the synthesized signal S _sint (t) from the reference signal S _et (t)

e ₀ (t) = S _et (t) -S _sint (t).

The dependence of e ₀ (t) on the current value of the angle x is shown in Fig.3. The maximum deviation e ₀ (t) modulo exceeds 4% (e _1max = 42.5 mV with a normalized amplitude value A = 1000 mV).

If we form a correction signal S _k (t) that exactly matches the shape and size of the error signal e ₀ (t), and then add it to the signal S _sint (t) in antiphase, the resulting signal N ₁ (t) will be in accuracy is equal to the reference signal S _et (t).

The task of generating the correction signal S _k (t) is performed by a frequency synthesizer 4 and a phase modulator 5. At the first output of the frequency synthesizer 4, a doubled frequency signal S ₁ (t) = Asin (2ω ₀ t) = Asin (ω ₁ t) is generated, at the second the output is the signal S ₂ (t) = Asin (4ω ₀ t) = Asin (2ω ₁ t), whose frequency is four times the frequency ω ₀ , and at the third, the signal S ₃ (t) = Asin (8ω ₀ t) = Asin (4ω ₁ t), the frequency of which is 8 times higher than the frequency ω ₀ (Figure 4).

As a result of the summation of the signals S ₂ (t) and S ₃ (t) at the output of the adder 10, a signal is generated

where k ₄ and k ₅ are the transfer coefficients of the adder 10 at the first and second inputs, respectively.

The transmission coefficient k ₄ is selected in such a way as to ensure equality of the amplitude value of the signal k ₄ S ₂ (t) and the maximum value E _0max (Fig. 3) of the error signal e ₀ (t), that is, k ₄ A = E _0max , the transmission coefficient k ₅ should be approximately seven times less than the coefficient k ₄ .

Shaper of control pulses 6 under the action of signal S ₁ (t) generates (Fig. 4) a square-shaped signal S _y (t) acting on the control input of switch 7, at the output of which a correction signal S _k (t) is supplied to the first input summing block 3.

The correction signal S _k (t) practically does not differ from the error signal e ₀ (t), therefore, at the output of the summing block 3, a “quasilinear” signal of triangular shape with slight deviations from the reference signal S _et (t) is formed.

A quantitative estimate of the linearization residual error can be calculated using the formula e ₂ (t) = S _et (t) -N ₁₂ (t), where N ₁₂ (t) is the “quasilinear" signal of a triangular shape obtained as a result of correction using the signal S ₀₂ (t) = k ₄ Asin (2ω ₁ t) + k ₅ Asin (4ω ₁ t).

In the prototype [5], the value of the residual error e ₁ (t) = S _et (t) -N ₁₁ (t), where N ₁₁ (t) is the “quasilinear” signal of a triangular shape, obtained as a result of correction using the signal S ₀₁ ( t) = k ₄ Asin (2ω ₁ t).

The results of analytical calculations and mathematical modeling for determining the residual error are presented in Fig. 5, whence it follows that when adjusting only for one harmonic with a frequency (2ω ₁ t), the value of the residual error e ₁ (t) decreased by about 7 times and amounted to 0, 62% of the normalized amplitude A ^* , and when corrected for two harmonics with frequencies (2ω ₁ t) and (4ω ₁ t), the value of the residual error e ₂ (t) decreased by about 24 times and amounted to 0.18% of the normalized amplitude values A ^* .

The frequency synthesizer 4 operates as follows. At the output of the first multiplier 16, a signal is generated

where m ₁ is the transfer coefficient of the first amplifier 13.

When m ₁ = 2, at the first output of the frequency synthesizer 4, a signal S ₁ (t) = sin (2ω ₀ t) = sin (ω ₁ t) is formed, and at the third output (Out3) of the multi-frequency functional generator (Fig.6, b) - signal N ₃ (t) = sin (2ω ₀ t) = sin (ω ₁ t).

The output of the first subtractor 23 generates a signal

When k ₆ = k ₇ = 1, a signal is generated at the fourth output of the frequency synthesizer 4

which arrives (Fig.6, b) at the sixth output (Out6) of the multi-frequency functional generator.

At the output of the second multiplier 17, a signal is generated

where m ₂ is the transfer coefficient of the second amplifier 14.

When m ₂ = 2, the signal S ₂ (t) = sin (4ω ₀ t) = sin (2ω ₁ t) is formed at the second output of frequency synthesizer 4, which is fed (Fig. 6, d) to the fourth output (Out4) of the multi-frequency functional generator.

At the output of the second subtractor 24, a signal is generated

With k ₈ = k ₉ = 1, a signal is generated at the fifth output of frequency synthesizer 4

which arrives (Fig.6d) at the seventh output (Out7) of the multi-frequency functional generator.

A signal is generated at the third output of frequency synthesizer 4

where m ₃ is the transfer coefficient of the third amplifier 18.

When m ₃ = 2, the signal S ₃ (t) = sin (8ω ₀ t) = sin (4ω ₁ t) is formed at the third output of the frequency synthesizer 4, which is fed (Fig. 6, e) to the fifth output (Out5) of the multi-frequency functional generator.

On the eighth (Out8) and ninth (Out9) outputs of the multi-frequency functional generator arrive (Fig.6, a) signals V ₁ (t) and V ₂ (t), respectively, from the first and second outputs of the source of quadrature signals 8.

The quasilinear signal of a triangular shape N ₁ (t) from the output of the summing block 3 is fed to the first output (Out1) of the multi-frequency functional generator, as well as to the input of the generator of bipolar rectangular pulses 11, from the output of which the signal N ₂ (t) goes to the second output (Out2 ) multi-frequency functional generator.

Using the proposed invention will expand the functionality of the device and improve the metrological characteristics of the generated signals.

Information sources

1. Ac. USSR 964965, IPC ³ H03B 21/02. A device for forming a frequency grid / Ryzhkov A.V. and others No. 2910583 / 18-09; declared 04/16/80; publ. 10.10.82, bull. Number 37. - 2 p.: 1 ill.

2. Ac. USSR 845262, IPC ³ H03B 21/02. Multi-frequency generator / Ryzhkov A.V. and others No. 2615100 / 18-09; declared 05/15/78; publ. 07.07.81, bull. Number 25. - 2 p.: 1 ill.

3. Pat. 2108655, Russian Federation, IPC ⁶ H03B 19/00. Digital multi-channel frequency grid synthesizer / Efimov S.A .; applicant and patent holder “Computing Center SB RAS”. No. 95101294/09; declared 01/30/95; publ. 04/10/98, bull. No. *. - 9 p.: 2 ill.

4. Pat. 2221327, Russian Federation, IPC ⁷ H03K 3/02. Functional Generator / Kim K.K. and etc.; applicant and patent holder “Petersburg State University of Railway Engineering”. No. 2001121641/09; declared 08/01/01; publ. 06/27/03, bull. No. *. - 7 p.: 5 ill.

5. Pat. 83669 Russian Federation, IPC ⁷ H03K 4/06 Additive driver of a signal of a triangular shape / Dubrovin BC, Zyuzin AM; applicant and patent holder Non-governmental scientific and educational institution “Saransk House of Science and Technology of the Russian Union of Scientific and Engineering Public Organizations” (NNOU “Saransk House of Science and Technology RSNIIOO”). No. 200910332; declared 02.02.2009; publ. 06/10/09, bull. No. 16. - 8 p.: 5 ill.

Claims (3)

1. A multi-frequency functional generator containing the first and second module calculators, a summing unit, a frequency synthesizer and a phase modulator made of a control pulse shaper and a switch, the output of which is connected to the output of a phase modulator, the second input of which is connected to the second input of the switch, the first input of which connected to the output of the driver of the control pulses, the input of which is connected to the first input of the phase modulator, while the output of the phase modulator is connected to the third input of the summing unit, the output and the first input of which are connected respectively with the first output of the multi-frequency functional generator and with the output of the first computer calculator, the input of which is connected to the first input of the frequency synthesizer, the second input of which is connected to the input of the second computer of the module, the third output of the multi-frequency functional generator is connected to the first the input of the phase modulator and with the first output of the frequency synthesizer, the second input of which is connected to the fourth output of the multi-frequency functional generator, characterized in that a quadrature signal source, an inverter, an adder, and a bipolar rectangular pulse generator, connected between the output of the summing unit and the second output of the multi-frequency functional generator, the fifth, sixth, and seventh outputs of which are connected to the third, fourth, and fifth outputs of the frequency synthesizer, respectively, are introduced into it the first and second inputs of which are connected to the corresponding outputs of the quadrature signal source, the control input of which is connected to the multi-frequency control bus functional generator, the eighth and ninth outputs of which are connected respectively to the first and second outputs of the quadrature signal source, while the inverter is connected between the output of the second module calculator and the second input of the summing unit, and the second and third outputs of the frequency synthesizer are connected respectively to the first and second inputs of the adder , the output of which is connected to the second input of the phase modulator. 2. The multi-frequency functional generator according to claim 1, characterized in that in the phase modulator the driver of the control pulses is made of an amplifier-limiter, and the switch is made of an analog multiplier. 3. The multi-frequency functional generator according to claim 1, characterized in that the frequency synthesizer is made of the first, second and third amplifiers, the first, second and third multipliers, the first, second, third and fourth quadrators, the first and second subtracters, the first amplifier is connected between the first input of the frequency synthesizer and the first input of the first multiplier, the second amplifier is connected between the output of the first multiplier and the first input of the second multiplier, between the output of which and the first input of the third multiplier the third amplifier, between the first input of the frequency synthesizer and the first input of the first subtractor, the first quadrator is turned on, the second quadrator is connected between the second input of the frequency synthesizer and the second input of the first subtractor, between the output of which and the second input of the second subtractor the fourth quadrator is turned on, the third quadrator is connected between the output of the first multiplier and the first input of the second subtractor, the output of which is connected to the second input of the third multiplier, the second input of the second multiplier is connected to the output of the first subtractor and the second input of the first multiplier is connected to the second input of the frequency synthesizer, the first, second and third outputs of which are connected to the outputs of the first, second and third multipliers, the fourth and fifth outputs of the frequency synthesizer are connected to the outputs of the first and second subtracters, respectively.

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