Device for measuring amplitude-frequency and phase-frequency characteristics of quadripoles with frequency converter

FIELD: measuring equipment engineering.

SUBSTANCE: generators of swaying frequency have first control inputs connected to output of control block, to first indicator block and input of adjustable generator of intermediate frequencies. One of outputs of intermediate frequencies generator is connected to second input of second phase detector. Output of first generator of swaying frequency is connected to one of inputs of first mixer of block for phase auto-adjustment of frequency, another input of which is connected to output of second swaying frequency generator. Signal input of supporting mixer is connected to moving contact of third switch, first fixed contact of which is connected to first fixed contact of fourth switch. Moving contact of switch is connected to amplifier output, input of which is connected to moving contact of first switch.

EFFECT: higher precision, higher efficiency.

1 dwg

 

The invention relates to the field of radio and can be used to control various devices of the microwave.

A well-known measure of complex coefficients of the transmission P4-36, P4-37/1, P4-38 (see Measurements in electronics. The Handbook. Edited by Kuznetsov. M.: Energoatomizdat. 1987. S.226-230)containing a sweep generator, the divider signal generator sweep on two channel measuring and reference measuring and reference faucets, heterodyne frequency Converter associated with the system phase-locked loop frequency generator sweep and out phase-sensitive indicator of the relationship of the levels of the signals in the measuring and reference channels.

The disadvantage of these measures is that they cannot measure the complex coefficients of the transmission of two, containing in its composition frequency converters, because the signals at the input and output of these two have different frequencies and for this reason cannot be included in the measuring channel of the device.

Here and further on by a quadrupole with a frequency Converter refers to a mixer in which heterodyne frequency conversion, which is the input signal, the input of the local oscillator and the output of the intermediate frequency (GTC), for which the local oscillator is an external device is, not belonging to the mixer.

Known measuring instruments under U.S. patent on a method (Patent number 6041077, Mar 21.2000, Int Cl7H 04 B 3/36, US cl 375/224) and the device (Patent number 6041694, May 16.2000, Int Cl7H 04 B 3/46, US cl 375/224) for measurement of the complex coefficients of the transmission device that contains the frequency Converter mixer, measurement capabilities are stated in the Internet on the website of Hewlett Packard, "Improving Network Analyzer Measurements of Frequency-translating Devices. Application-Note 1287-4". However, this method of measurement is identical to the previously declared methods in the USSR (as the USSR №1475347, CL G 01 R 27/28, 1986, and as of the USSR №1596278, CL G 01 R 27/28, 1988). The disadvantage of these devices is that they do not allow to measure the mixers with variable intermediate frequency. In addition, due to the lack of these devices of the amplifier and attenuator included in the measuring path of the test mixer, a measurement error due to different signal levels when determining the sum and difference of the phase shifts. In these devices is missing and stabilization of the absolute value of the frequency sweep generator.

The closest analogue to the proposed device is a device for measuring the amplitude-frequency and phase-frequency characteristics of four with a frequency Converter (A.S. USSR №1661682, IPC(5) G 01 R 27/28), containing two generators swinging frequent is you, the first control inputs of which are connected with the output of the control unit, the other end of which is connected to the third input of the indicator and the input of the tunable oscillator intermediate frequency third output of which is connected with the second input of the second phase detector, the output of the first oscillator sweep is connected to one of inputs of the first mixer unit phase-locked loop, another input connected to the output of the second generator sweep, at the same time connected with heterodyne reference input of the mixer signal input of which is connected to a movable contact of the third switch, the first stationary contact of which is connected with the first fixed contact of the fourth switch, the movable contact of which is connected to the output amplifier, whose input is connected to a movable contact of the first switch, the first stationary contact through which the attenuator is connected to one of the outputs of the first divider signal, the second output of which is connected with the first fixed contact of the second switch, the second stationary contact of which is connected to the second stationary contact of the fourth switch, the output of the first mixer, a phase-locked loop connected to the first inputs of the first phase detector and a second mixer unit phase is avtopodstroiki frequency, the output of which is connected to the first input of the second phase detector, the output of which is connected to the third input of the first oscillator oscillating frequency, a second input connected to the first output of the tunable oscillator intermediate frequency and the input of the second divider signal, the outputs of which are connected with the second fixed contact of the fifth and sixth switches, the first fixed contacts which are connected, the movable contact of the fifth switch coupled to the output of the reference mixer and the movable contact of the sixth switch is connected to the signal input of the mixer intermediate frequency of the reference channel, the output of which is connected to a second input of the indicator, the first input connected to the output of the mixer intermediate frequency measuring channel heterodyne input of which is connected to a second input of the mixer intermediate frequency reference channel, the second output of the tunable oscillator intermediate frequency and the second input of the second mixer unit phase-locked loop, the output of the indicator is connected to the input of the decision making unit, the input of the third divisor signal is connected to the output of the first generator sweep, one output of the third divider signal is connected to the input of the first divider signal, the other output to the signal input epithema the quadrupole with a frequency Converter, heterodyne input connected to the output of the second generator sweep, at the same time connected to one of the auxiliary inputs of the mixer, the other input of which is connected to a movable contact of the second switch and the output of the auxiliary mixer connected to the first input of the mixer intermediate frequency measuring channel, the output of two-port network with a frequency Converter connected to the third fixed contact of the sixth switch.

The disadvantages of this device is the lack of stabilization of the absolute value of the frequency sweep generator. Change the absolute value of the frequency of these generators during the measurement result of the two components of the total error in the measurement of phase shifts.

1. Due to the nonlinearity of the phase-frequency characteristic (PFC) of the test quadrupole with a frequency Converter. Change in time of the absolute value of the frequency of the probing signal from the sweep generators 1 and 2 (GCC 1 and GCC 2) leads to a change in the measured phase shift due to the different magnitude in each frequency point of the FR. The specific value of the phase shift in the frequency point is determined by the type of nonlinear resistance, is used as a frequency-converting element and mo is et to reach 5-7° at frequencies of 2-6 GHz.

2. Due to the continuous variation (jitter) frequency in time. This error describes the known expression

where Δϕ - the phase change over a period of time from t1to t2;

f - frequency probing signal.

When frequency stability 10-4at a frequency of 1·109Hz Δϕ can reach several degrees.

The total measurement error of the phase due to the instability of the two sweep generators equal to twice the value of the sum of both errors and up to 20°.

To reduce this error, you need to stabilize the frequency of one of the sweep generators. Because the first and second sweep generators covered by the total system phase-locked loop, therefore, stabilization of one of them leads to the automatic stabilization and the second oscillator oscillating frequency.

The technical objective of the proposed technical solution is to improve the accuracy of the measurement phase-frequency characteristics of two-conversion frequency mixer by improving the frequency stability of one of the two sweep generators.

For the technical solution proposed in the known device for measuring the ampli is odno-frequency and phase-frequency characteristics of four with a frequency Converter, containing the first and second sweep generators, the control unit, the first and second divisor signal, the attenuator, the first switch, the first mixer of the phase-locked loop, the second switch, the third switch, the amplifier, the second mixer phase-locked loop, the first phase detector, an auxiliary mixer, reference mixer, the fourth switch, the second phase detector, a tunable oscillator intermediate frequency, the fifth switch, the intermediate frequency divider, the test quadrupole with a frequency Converter, the sixth switch, the mixer intermediate frequency measuring and reference channel indicator and a crucial block, optionally enter a divider with variable division factor the divider lo signal, the third phase detector and the reference generator.

The first control inputs of the sweep generator is connected to the output of the control unit, the third input of the indicator and the input of the tunable oscillator intermediate frequency third output of which is connected to a second input of the second phase detector. The output of the first generator sweep simultaneously connected to the first divider signal and one of the inputs of the first mixer, a phase-locked loop, the other input of which is connected to the n with the output of the second generator sweep, which is simultaneously connected to the input of the divider lo signal, one output of which is connected to one of the inputs of the divider with a variable division ratio, and the other input of the divider lo signal is connected simultaneously with heterodyne auxiliary inputs, the reference and the test mixers. Signal reference input of the mixer is connected to a movable contact of the third switch, the first stationary contact of which is connected with the first fixed contact of the fourth switch, the movable contact of which is connected to the amplifier output, the input of which is connected to a movable contact of the first switch, the first stationary contact through which the attenuator is connected to one of the outputs of the second divider signal, an input connected to the first output of the first divider signal, the second output of which is connected to the signal input of the test quadrupole with a frequency Converter. The second output of the second divider signal is connected to the first fixed contact of the second switch, the second stationary contact of which is connected to the second stationary contact of the fourth switch. Second fixed contacts of the first and third switches are interconnected. The output of the first mixer, a phase-locked loop connected to the first input of the second mixture is the determinant of the block phase-locked loop and the first input of the first phase detector, the second input is connected to the first output of the tunable oscillator intermediate frequency and the entrance to the third divisor signal, the first output of which is connected to the second stationary contact of the fifth switch, the first stationary contact connected to a second output of the third divider signals. The movable contact of the fifth switch coupled to the output of the reference mixer. The third stationary contact of the sixth switch is connected to the output of the test quadrupole with a frequency Converter. The output of the second mixer phase-locked loop is connected to one of inputs of the second phase detector, another input connected with the second input of the second mixer phase-locked loop and frequency heterodyne input of the mixer intermediate frequency measuring and reference channels. Signal input of the mixer intermediate frequency measuring channel is connected to the output of the auxiliary mixer. Signal input of the mixer intermediate frequency of the reference channel is connected to a movable contact of the sixth switch. The output of the mixer intermediate frequency measuring channel is connected to one of inputs of the indicator, a second input connected to the output of the mixer intermediate frequency of the reference channel. The third input of the indicator is connected to the output of tunable is the first intermediate frequency generator, the output of the control unit, the first inputs of the first and second sweep generators and the second input of the divider with a variable division ratio, the output of which is connected to the first input of the third phase detector, a second input connected to the output of the reference oscillator. The output of the third phase detector connected to the second input of the second generator sweep. The output of the first phase detector connected to the third input of the first oscillator oscillating frequency, a second input connected to the output of the second phase detector. The output indicator is connected to the input of a casting device.

A distinctive feature of the proposed device for measuring the amplitude-frequency and phase-frequency characteristics of four with a frequency Converter includes the introduction of an additional unit of the system phase-locked loop consisting of a divider lo signal, a divider with a variable division ratio of the third phase detector and the reference oscillator, allowing stabilization of the absolute value of the frequency of the second oscillator oscillating frequency, which together with existing and new relationships and blocks help to achieve the desired technical result. As a result of this reduced measurement error phase with the et increase the stability of the frequency of the second and first sweep generator, which are connected by a system of phase-locked loop consisting of the first and second mixers, phase-locked loop frequency, the first and second phase detectors. A collection of newly commissioned and existing nodes can improve the stability of the frequency of the second oscillator sweep mode variable intermediate frequency when the frequency is constant, but relatively it is rebuilt first intermediate frequency generator, and thus increases the accuracy of phase measurement in this mode.

The drawing shows a block diagram of the proposed device for measuring the amplitude-frequency and phase-frequency characteristics of four with a frequency Converter.

The device contains the generators 1 and 2 oscillating frequency, the control unit 3, the divider 4 with a variable division ratio of the first divider signal 5, the second divider signal 6, the attenuator 7, the first switch 8, the first mixer of the phase-locked loop 9, the third phase detector 10, the second switch 11, the divider signal of the local oscillator 12, the third switch 13, an amplifier 14, a second mixer, a phase-locked loop 15, the first phase detector 16, the reference generator 17, an auxiliary mixer 18, the reference mixer 19, the fourth switch 20, the second phase detector 21, prestrain the Amy the intermediate frequency generator 22, the fifth switch 23, the third divisor signal 24, the test mixer 25, the sixth switch 26, the mixer intermediate frequency measuring channel 27, the mixer intermediate frequency of the reference channel 28, the indicator 29, the deciding unit 30.

The first control inputs of oscillators 1 and 2 sweep connected to the output of the control unit 3, the third input of the indicator 29 and the input of the tunable intermediate frequency generator 22, the third output of which is connected to a second input of the second phase detector 21; the output of the generator 1 sweep is connected to one of inputs of the first mixer unit phase-locked loop 9, the other input connected to the output of the second generator sweep 2; signal reference input of the mixer 19 is connected to a movable contact of the third switch 13, the first stationary contact of which is connected with the first fixed contact of the fourth switch 20, the movable contact of which is connected with the output of the amplifier 14, the input of which is connected to a movable contact of the first switch 8, the first stationary contact of which through the attenuator 7 is connected to one of the outputs of the second divider signal 6, the inlet of which is connected to the first output of the first divider signal 5, the second output of the second divider signal 6 is connected with the first still contactingthe switch 11, the second stationary contact of which is connected to the second stationary contact of the fourth switch 20, the output of the first mixer, a phase-locked loop 9 is connected to the first input of the first phase detector 16 and the first input of the second mixer phase-locked loop 15, the output of which is connected to the first input of the second phase detector 21, the output of which is connected with the second input of the generator 1 sweep, a third input connected to the output of the first phase detector 16, a second input connected to the first output of the tunable intermediate frequency generator 22 and the entrance to the third divisor signal 24, the outputs of which are connected with the second fixed contact 23 and the fifth sixth 26 switches the first fixed contacts which are connected, the movable contact of the fifth switch 23 is connected to the output of the reference mixer 19 and the movable contact of the sixth switch 26 is connected to the signal input of the mixer intermediate frequency of the reference channel 28, the output of which is connected to a second input of the indicator 29, the first input connected to the output of the mixer intermediate frequency measuring channel 27, heterodyne input of which is connected to heterodyne the input of the mixer intermediate frequency of the reference channel 28, the second input of the tunable gene is atora intermediate frequencies 22 and the second input of the second mixer unit phase-locked loop 15, the third stationary contact of the sixth switch 26 is connected to the output of the test mixer 25, a signal input connected to the second output of the first divider signal 5, the input connected to the output of the generator 1 oscillating frequency; signal input of auxiliary mixer 18 is connected to a movable contact of the second switch 11, the output of the auxiliary mixer 18 is connected to the signal input of the mixer intermediate frequency measuring channel 27, the output of the indicator 29 is connected to the input of a casting device 30, the output of the reference oscillator 17 is connected to one of inputs of the third phase detector 10, the other input connected to the output of the divider with a variable division ratio of 4, first input connected to the second output of the divider signal of the local oscillator 12, the other end of which is simultaneously connected to heterodyne the auxiliary inputs of the mixer 18, the reference mixer 19 and the test mixer 25; the input of the divider signal of the local oscillator 12 is connected to the output of the generator 2 sweep; the second output of the divider with a variable division ratio of 4 is connected to the output of the control unit 3; the output of the third phase detector 10 is connected to a second input of the generator 2 sweep.

The device operates as follows.

GCC 1 and GCC 2 can operate in two modes.

the operation of the first variable intermediate frequency voltage from the control unit 3 sets the initial difference between the frequency ω 1, GCC 1 and the frequency ω2GCC 2 equal to the first intermediate frequency band analysis of the quadrupole 25 with frequency conversion. The same voltage is set to the initial value of the first variable intermediate frequency ω3signals tunable intermediate frequency generator 22 is removed from its first output, equal to the initial frequency band analysis. The same voltage with a voltage divider with variable division factor (DPCD) 4 sets the division ratio of this magnitude, that he divide the frequency of the signal from GCC 2 supplied through the divider lo signal 12 at its signal input, so that it was equal to the frequency of the reference oscillator 17. The output signal DPKG 4 and the reference oscillator 17 is compared to a third phase detector 10, and the result of the comparison in the form of a regulating voltage to the second input GCC 2, adjusting it so that the initial frequency ω2with accuracy up phase was equal to the frequency of the reference oscillator 17, multiplied by the division factor DPKG 4, and is determined by the expression:

ω2=n ωog,

where n is the division ratio of DPCD 4;

ωog- frequency signal of the reference oscillator.

The absolute value of the frequency ω2signal GCC 2 is set by the choice of the coefficient of Affairs is of n DPCD 4, and its stability in time is determined by the stability of the reference oscillator 17.

The choice of a sufficiently large division ratio n can significantly reduce the frequency of the reference oscillator 17 as compared with the frequency ω2and translate it from the microwave frequency range in the low frequency range, where the frequency stability can be achieved through the application of temperature-controlled quartz resonators. Changing the division factor n allows you to change the frequency ω2without changing the frequency of the reference oscillator ωog.

Then relatively GCC 2 configured on a fixed frequency, enabled sweep GCC 1 in the range equal to the analysis bandwidth at the intermediate frequency of the investigated two-port network with a frequency Converter 25. While synchronously with GCC 1 swiperboy tunable intermediate frequency generator 22 in a predetermined intermediate frequency range.

Simultaneously with the signals of the first intermediate frequency in the tunable intermediate frequency generator 22 produces signals auxiliary intermediate frequency removed from its second output, shifted by a constant amount Ω with regard to the signals of the first intermediate frequency accuracy and phase at any point.

Part of the intermediate frequency signals Ω from the output of the mixer 9 phase-locked loop often is s (PLL) is applied to one of inputs of the mixer 15 PLL, where is mixed with the auxiliary signal of frequency tunable intermediate frequency generator 22. Resulting from this signal the second constant intermediate frequency Ω output of this mixer is fed to one input of phase detector 21, where it is compared with the reference signal frequency Ωgenerated in the tunable intermediate frequency generator 22 and removed from its third output, and the result of comparison output from the second phase detector 21 is supplied to one input of GCC 1, controlling its frequency ω1so, what's the difference between it and the frequency ω2from GCC 2 up to a phase is equal to the current value of the first variable intermediate frequency ω3.

In constant mode, the first intermediate frequency ω3using the control unit 3 is synchronous swing GCC 1 and GCC 2 in the microwave frequency range, with one input of the first mixer 9 PLL is part of the signals from the outputs of these generators, and the resulting mixing signals of the first (variable) intermediate frequency output of mixer 9 PLL receives on one input of phase detector 16 which compares signals from the first intermediate frequency used as a reference from the first output of the tunable oscillator 22 intermediate the x frequencies. The result of the comparison is fed to one input of GCC 1, controlling its frequency during the swing so that the frequency difference between him and GCC 2 up to a phase equal to the first intermediate frequency, which is configured tunable intermediate frequency generator 22.

In this mode, synchronously with the sweep GCC 1 and GCC 2 controlling voltage from the control unit 3 changes the division factor n of the divider with a variable division ratio of 4, so that ω2=n ωogwhere ωog- frequency signal from the reference oscillator 17. This achieves stabilization of the absolute value of the frequency signal ω2that is determined by the stability ωogfrom the reference oscillator 17.

In modern DPCD, for example, CPPL-5, ADF4113 and their other division ratio is set to a digital binary code. In GCC type YA2R-74, YA2R-75, YA2R-76, etc. frequency is also a digital binary code. Speed adjustment DPKG does not exceed 250 milliseconds, the maximum operating frequency in DPCD type ADF4113 using prescaler up to 4 GHz. There are divisors and up to 20 GHz.

Each time the device is switched on in the beginning are calibrated, the goal of which is to determine the true phase-frequency characteristics of the auxiliary mixer. Since then, it zapomina is carried out in the indicator memory and, when needed, is reproduced on the screen of the cathode ray tube (CRT).

In the calibration mode in position 1 of switch 8, 11, 13, 20, 23 and 26 is implemented by a circuit for measuring the phase difference between the output signals of the auxiliary 18 and the base 19 of the mixers. The divisor is the separation of the signal into the auxiliary and reference channels. The auxiliary channel is formed by one of the outputs of the divider 6, the switch 11, the auxiliary mixer 18 and the electrical paths connecting these nodes.

The reference channel is formed by another output of the divider 6, the attenuator 7, switch 8, the amplifier 14, the switches 20, 13, reference mixer 19 and the electrical paths connecting these nodes.

Before measurement is the alignment of the electrical lengths of the auxiliary and reference channels and paths of signals lo after their branching divider 12. Next, the marking of auxiliary and reference channels of the device so that when measuring the phase difference, the phase in the auxiliary channel has been decreasing, and in the reference - subtracted this difference.

The signal in the auxiliary channel can be represented in the form

where- amplitude signal value;

- the initial phase of the signal in the auxiliary channel on the first (signal) input auxiliary will smusic the La.

The signal in the reference channel can be represented in the form

where- amplitude signal value;

- the initial phase of the signal in the reference channel at the reference input of the mixer.

The auxiliary channel signal through the switch 11 is supplied to the first input of the auxiliary mixer 18, and the signal of the reference channel through the attenuator 7, switch 8, the amplifier 14 and the switch 20 is supplied to the first (signal) to the reference input of the mixer 19, which is converted by the signal from GCC 2 signals in the first (variable) intermediate frequency ω3. Frequency conversion can be both up and down, and meets the expression

where ω3the first (variable) intermediate frequency;

ω1- frequency signals GCC 1;

ω2- frequency signals GCC 2.

For example, the device is converting

Then on the output of the auxiliary mixer 18 is a signal described by the expression

where- the amplitude of the signal,

- the initial phase of the signals from GCC 1 on the ground (signal) input auxiliary will sosite what I 18;

- the initial phase of the signals from GCC 2 on the second (heterodyne) auxiliary mixer 18;

Δϕ1is the desired phase shift of the auxiliary mixer 18 made phase signals of the first intermediate frequency in the conversion.

Given the condition (4), have

After conversion at the output of the reference mixer 19 is a signal described by the expression

wheresignal of the first intermediate frequency in the reference channel;

- the amplitude of the signal,

- the initial phase of the signals from GCC 1 on the ground (signal) the reference input of the mixer;

- the initial phase of the signals from GCC 2 on heterodyne (second) reference input of the mixer;

Δϕ2the phase shift attenuator 7;

Δϕ3the phase shift of the amplifier 14;

Δϕ4the phase shift of the reference mixer 19 made phase signals of the first intermediate frequency in the conversion process.

Given the condition (4), have

The signals of the first intermediate frequency from the output of the auxiliary 18 and the support 19 mixers arrive at the signal inputs of mixers prom is mediate frequency measuring 27 and the base 28 of the channels, respectively, where using a heterodyne signal from the second output of the tunable intermediate frequency generator 22, they are converted into signals of a constant low intermediate frequency - Ωthat arrive at the measuring and reference inputs of the indicator relations 25, where calculated the ratio of their amplitudes and phase difference, and the result is fed into a casting block 30, which is fixed.

Assuming that the amplitude-frequency and phase-frequency characteristics of the mixers 27 and 28 intermediate frequency measuring and reference channels are identical, and the indicator 29, which represents an indicator of relations between the two signals, measures the phase difference between the signals of the measuring and reference channels of the second low intermediate frequency, the result of comparing the phase difference in the indicator can be represented by the expression

where a is the phase difference, the degree considering the sign;

k - coefficient of proportionality;

the function represented by the phase detector.

Almost all attenuators microwave have a linear phase characteristic and, therefore, the electrical length can be compensated electrical length of the microwave path. Given this fact, it can be argued that the phase shift Δϕ2attenuator 7 may be scomp sirawan phase shift in the measuring channel i.e.

Taking into account (10) and assuming that the electrical lengths of the paths of the measuring and reference channels lopairwise equalindicator relations 29 will record the results of measurements of phase shifts in the form

In position 2 of switch 8, 11, 13, 20, 23 and 26 is implemented scheme for measuring the amount of phase shifts auxiliary 18 and the support 19 to the mixer.

The signal of the first variable intermediate frequency from the first tunable intermediate frequency generator 22 by the second divisor signal 24 is divided into two channels: auxiliary and reference.

The signal of the reference channel through the switch 23 is input to the intermediate frequency of the reference mixer 19. When this auxiliary 18 and the support 19 mixers switches 8, 11, 13 and 20 are connected in series so that the input microwave auxiliary mixer 1 8 via the amplifier 14 is connected with the input signal of the UHF reference mixer 19. In this case, the input signal of the UHF reference mixer 19 in the inverse transform and its selective properties of a signal sum-frequency ω123which after amplification by the amplifier 14 is fed to the input of the auxiliary mixer 18. is the auxiliary input of mixer 18 is a signal, described by the expression

where- the initial phase of the signal from the tunable intermediate frequency generator 22 in the reference channel;

Δϕ3the phase shift of the amplifier 14;

Δϕ4the phase shift introduced by the reference mixer 19 in phase intermediate frequency signals ω3;

- the initial phase of the signal from GCC 2 to heterodyne the auxiliary input of mixer 18.

The gain of the amplifier 14 is set in such a way as to compensate for the loss of conversion of the reference mixer 19, therefore, the amplitude at the input of the auxiliary mixer 18 is practically unchanged compared with the scheme, when it is included to measure the difference of the phase shifts.

After conversion in the auxiliary mixer 18 at its output has a signal

where- the initial phase of signals in the opposite heterodyne auxiliary channels 18 and the support 19 mixers;

Δϕ4the phase shift of the reference mixer.

Join local oscillator which performs GCC, through the divider signal of the local oscillator 12 to the auxiliary 18 and the support 19 to the mixer remains unchanged compared with the scheme for measuring the different the different phases and so

Then this signal is fed to the first (signal) input to the mixer intermediate frequency measuring channel 27 where using heterodyne signal from the tunable intermediate frequency generator 22 it is the same as in the reference channel using the mixer intermediate frequency of the reference channel 28, is converted into a signal of a second constant intermediate frequency Ωthat is fed to the measuring and reference inputs of the indicator relations 29.

Due to the fact that when measuring the sum and difference of the phase shifts accession lo GCC 2 to the auxiliary 18 and the support 19 to the mixer does not change, the absolute stability of the frequency ω2also remains constant and is determined by the system consisting of DPCD 4, the phase detector 10 and the reference oscillator 17, the connection of which is invariable.

Given that the indicator 29 determines the phase difference between the signals on its signal (ground) and reference (second) inputs, the result can be represented in the form

where k1is the coefficient of proportionality;

the function of phase detector indicator;

- the initial phase of the signal from the tunable oscillator 18 intermediate frequencies, pornokanal.

At the equal electrical length of the paths of the measuring and reference channels

Indicator 29 will record the measurement of the amount of phase shifts in the form

In=Δϕ1+Δϕ3+Δϕ4,

which comes at a crucial block 30.

Crucial unit 30 after the receipt of his sum of shifts of phases produces the solution of a system of equations

Previously calculated and stored in RAM indicator 29 characteristics of the true phase shift is the absolute phase response of the auxiliary mixer 18. The difference of the phase shifts between the test mixer 25 and the auxiliary mixer 18, the measured phase detector indicator 29, handled it by comparing with the stored absolute phase-frequency characteristic of the reference mixer 19 with signs and reproduced on the display or a CRT screen and the registration Board in each frequency point in the form of a phase-frequency characteristics and the true values of the phase shift of the test mixer 25 (quadrupole with frequency Converter).

The transfer ratio of the amplitude-frequency characteristics of the test mixer 25 is measured similarly.

Device for measuring the amplitude-frequency and phase-frequency characteristics of four with conversions is the user frequency, contains two oscillator oscillating frequency, the first control inputs of which are connected with the output of the control unit, the third input of the indicator and the input of the tunable oscillator intermediate frequency third output of which is connected to a second input of the second phase detector, the output of the first oscillator sweep is connected to one of inputs of the first mixer unit phase-locked loop, another input connected to the output of the second oscillator oscillating frequency signal to the reference input of the mixer is connected to a movable contact of the third switch, the first stationary contact of which is connected with the first fixed contact of the fourth switch, the movable contact of which is connected to the amplifier output, an input connected to a movable contact of the first switch, the first stationary contact through which the attenuator is connected to one of the outputs of the second divider signal, an input connected to the first output of the first divider signal, the second output of the second divider signal is connected to the first fixed contact of the second switch, the second stationary contact of which is connected to the second stationary contact of the fourth switch, the output of the first mixer, a phase-locked loop connected to the first input of the first phase detector is a and the first input of the second mixer unit phase-locked loop, the output of which is connected to the first input of the second phase detector, the output of which is connected to a second input of the first oscillator oscillating frequency, a third input connected to the output of the first phase detector, a second input connected to the first output of the tunable oscillator intermediate frequency and the entrance to the third divisor signal, the outputs of which are connected with the second fixed contact of the fifth and sixth switches, the first fixed contacts which are connected, the movable contact of the fifth switch coupled to the output of the reference mixer and the movable contact of the sixth switch is connected to the signal input of the mixer intermediate frequency of the reference channel, the output of which is connected to a second input of the indicator first input connected to the output of the mixer intermediate frequency measuring channel heterodyne input of which is connected to heterodyne the input of the mixer intermediate frequency of the reference channel, the second input of the tunable oscillator intermediate frequency and the second input of the second mixer unit phase-locked loop, the third stationary contact of the sixth switch is connected to the output of the test mixer signal input of which is connected with the second output of the first divider signal, the signal input of auxiliary materials is inogo mixer is connected to a movable contact of the second switch, the output of the auxiliary mixer is connected to the signal input of the mixer intermediate frequency measuring channel, the output of the indicator is connected to the input of the decision making unit, characterized in that it additionally introduced divider with a variable division ratio of the divider lo signal, the third phase detector and the reference oscillator, the output of which is connected to one of inputs of the third phase detector, another input connected to the output of the divider with a variable division ratio, the first input connected to the second output of the divider lo signal, the other output of which is simultaneously connected to heterodyne the auxiliary inputs of the mixer, the reference mixer and the test of the mixer, the input of the divider signal lo is connected to the output of the second oscillator oscillating frequency, the second output of the divider with variable division factor is connected to the output of the control unit, the output of the third phase detector connected to the second input of the second generator sweep.



 

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2 cl, 3 dwg

FIELD: instrument making, namely technique for five-position control of motion of different physical nature objects.

SUBSTANCE: in order to achieve desired result primary transducer includes in addition third inductive (transformer type) converter and secondary transducer includes in addition resistor, capacitor, three diodes, four reference units. First and second outlets of first reference member are connected respectively with cathode of first diode and anode of third diode.

EFFECT: enlarged functional possibilities of pickup.

5 cl, 8 dwg

FIELD: instrument making, namely technique of three position control of motion of different physical nature objects.

SUBSTANCE: in order to achieve desired result pickup includes in addition capacitor, resistor, first and second voltage dividers. First inlet of secondary transducer is connected with first outlet of first voltage divider that is connected with anode (cathode) of third diode. Cathode (anode) of third diode is connected with second inlet of second comparator.

EFFECT: enlarged functional possibilities.

6 cl, 8 dwg

FIELD: instrument making, namely technique for multi-position control of motion of different physical nature objects.

SUBSTANCE: in order to achieve desired result pickup includes reference circuit having connected in series first and second double-terminal networks. First and second terminals of AC source are connected respectively with first outlets of first and second double-terminal networks whose second outlets are connected with anode (cathode) of additional diode. Cathode (anode) of additional diode is connected with first outlets of additional resistor and capacitor and with second inlets of first and second comparators.

EFFECT: enlarged functional possibilities.

7 cl, 13 dwg

FIELD: radio-electric measurements.

SUBSTANCE: device has multiplexer, filtering block, analog-digital converter, square-ware generator, two accumulating adders, functional converter, performing in simplest case operations of division and square root, as well as control block and white noise generator. Device uses random process with broad range as test signal and allows to measure amplification coefficient concurrently in certain range of frequencies. Products of nonlinear distortions are taken in consideration, which accompany operation of real amplifiers and which influence shape of output signal as well as its level.

EFFECT: higher precision.

2 dwg

Meter gain // 2242016
The invention relates to the field of electrogravimetry and can be used for online measurement of gain broadband amplifiers and audio amplifiers, as well as for automated control paths passing audio signals

The invention relates to the field of radio, and is intended for integral assessment of the level of frequency distortion of a two-port, such as audio amplifiers

The invention relates to the field of radio, and is intended for integral assessment of the level of frequency distortion of a two-port, for example, audio amplifiers

The invention relates to the field of radio and can be used when building level meters frequency distortion of a two-port, such as audio amplifiers

FIELD: radio-electric measurements.

SUBSTANCE: device has multiplexer, filtering block, analog-digital converter, square-ware generator, two accumulating adders, functional converter, performing in simplest case operations of division and square root, as well as control block and white noise generator. Device uses random process with broad range as test signal and allows to measure amplification coefficient concurrently in certain range of frequencies. Products of nonlinear distortions are taken in consideration, which accompany operation of real amplifiers and which influence shape of output signal as well as its level.

EFFECT: higher precision.

2 dwg

FIELD: instrument making, namely technique for multi-position control of motion of different physical nature objects.

SUBSTANCE: in order to achieve desired result pickup includes reference circuit having connected in series first and second double-terminal networks. First and second terminals of AC source are connected respectively with first outlets of first and second double-terminal networks whose second outlets are connected with anode (cathode) of additional diode. Cathode (anode) of additional diode is connected with first outlets of additional resistor and capacitor and with second inlets of first and second comparators.

EFFECT: enlarged functional possibilities.

7 cl, 13 dwg

FIELD: instrument making, namely technique of three position control of motion of different physical nature objects.

SUBSTANCE: in order to achieve desired result pickup includes in addition capacitor, resistor, first and second voltage dividers. First inlet of secondary transducer is connected with first outlet of first voltage divider that is connected with anode (cathode) of third diode. Cathode (anode) of third diode is connected with second inlet of second comparator.

EFFECT: enlarged functional possibilities.

6 cl, 8 dwg

FIELD: instrument making, namely technique for five-position control of motion of different physical nature objects.

SUBSTANCE: in order to achieve desired result primary transducer includes in addition third inductive (transformer type) converter and secondary transducer includes in addition resistor, capacitor, three diodes, four reference units. First and second outlets of first reference member are connected respectively with cathode of first diode and anode of third diode.

EFFECT: enlarged functional possibilities of pickup.

5 cl, 8 dwg

FIELD: measurement technology.

SUBSTANCE: analyzer can be used for measuring level of frequency distortions introduced by audio channel. Analyzer has two spectrum analyzers which are used to determine signal spectra at output and input of tested four-terminal network. Input and output signal spectra are subject to normalization and are introduced into subtraction unit and later to unit for determining normalized signals difference module. Signal from unit for determining module is sent to integrator to find end value, which characterizes area of frequency distortions introduced by four-terminal network. According to another version of analyzer the module is substituted by squarer. Analysis of frequency characteristics can be performed without turning four-terminal network into special measuring mode.

EFFECT: improved truth of information; increased precision of measurement.

2 cl, 3 dwg

FIELD: measurement technology.

SUBSTANCE: measuring unit is used for measuring time shifts between output and input signals induced in real four-terminal networks, for example, in amplifiers of audio signals. Measuring unit can be used for measuring as random signals and determined monoharmonic signals. Measuring unit has two extremum selection units which have outputs connected with inputs of time shift measuring unit. Inputs of extremum selection unit have to be inputs of measuring unit. Measurement of time shifts between extreme of output and input signals allows to eliminate errors caused by shifts in signal zero line in four-terminal network and influence of non-linear distortions on shape of output signal.

EFFECT: reduced errors; reduced influence of non-linear distortions.

2 cl, 3 dwg

FIELD: measuring equipment engineering.

SUBSTANCE: generators of swaying frequency have first control inputs connected to output of control block, to first indicator block and input of adjustable generator of intermediate frequencies. One of outputs of intermediate frequencies generator is connected to second input of second phase detector. Output of first generator of swaying frequency is connected to one of inputs of first mixer of block for phase auto-adjustment of frequency, another input of which is connected to output of second swaying frequency generator. Signal input of supporting mixer is connected to moving contact of third switch, first fixed contact of which is connected to first fixed contact of fourth switch. Moving contact of switch is connected to amplifier output, input of which is connected to moving contact of first switch.

EFFECT: higher precision, higher efficiency.

1 dwg

FIELD: amplitude-frequency characteristics of quadripoles.

SUBSTANCE: control of quadripole is realized in two stages. At first stage, estimation stage, N counts of measurements results are received during length T of one signal period, and on second stage, analysis stage, during time T received signal estimation results are recognized with determining of class of technical state of object (like breakdown). To realize first stage of control, to present clock pulse generator, first counter, delay element, first register, first AND element, adder, additionally inserted are two keys, two analog-digital converters, second register and operative memory block for estimation results, to realize second control stage additionally to first and second comparison block, indication block, inserted are breakdowns signs memory block, breakdown counters and commutator, and for controlling control stages to present launch element, first counter, second AND element, key element is additionally inserted.

EFFECT: higher speed of operation.

5 dwg

FIELD: measurement technology.

SUBSTANCE: method can be used for automatic estimation of state of distributed processes or objects of different physical nature. Measurement signal vector, i.e. noises disturbances and distortions with wide spectral range are formed additionally. After measurement information signals, calibration (control) signals or noise, disturbance or distortion signals are received the functional conversion of measurement signals is performed calculation of spectral characteristics of the signals. Measurement signals are transformed for any individual analyzed harmonic component of measurement signals.

EFFECT: improved precision of measurement.

2 cl, 11 dwg, 5 tbl

FIELD: measurement technology; electric engineering.

SUBSTANCE: device can be used for estimating changes in signal frequency range when the signal passes through signal transmission/amplification paths which signals have precision multi-band frequency correction. Device helps to observe results of introduced correction. Device has two spectrum analyzers which are used for determining signal spectra at input and output of tested four-terminal networks. Spectra of input and output signals are normalized and introduced into normalized signals' comparison unit. Signal from module determining unit is sent to indicator for visual representing of result of comparing depending on frequency. Device provides ability of visual estimation of degree of change in random signal's spectral form when signal passes through four-terminal network having frequency-dependent characteristics.

EFFECT: improved efficiency; improved precision.

5 cl, 5 dwg

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