Method of measurement of phase shifts between two harmonic signals of similar frequency

FIELD: measuring equipment.

SUBSTANCE: method for measuring phase shifts between two harmonic signals of the same frequency, providing high accuracy of measurement by using the harmonic voltage symmetry property. It can be used in the development of phase shift meters of various devices of high-frequency and ultra-high-frequency ranges. The essence of the method consists in the fact that the team channel sets the fetch time immediately before going through the voltage zero measured and memorized the voltage corresponding to the sample. Next is determined by the time the second sample, following immediately after transition through zero voltage the voltage equal to the opposite sign to the voltage of the first sample. The time of transition of the voltage of the reference channel through zero is defined as the arithmetic average of the time of appearance of the first and second samples. Similarly, in the measuring channel is set to the first sample immediately before going through the voltage zero measured and memorized the voltage corresponding to the sample. Next is determined by the time the second sample, following immediately after transition through zero voltage the voltage equal to the opposite sign to the voltage of the first sample. The time of transition of the voltage of the measuring channel through zero is defined as the arithmetic average of the time of appearance of the first and second samples. The sought phase shift between two harmonic signals of the same frequency is defined as the difference between the time of zero crossing of the voltage of the measuring and reference channels multiplied by the circular frequency of the signals under study.

EFFECT: increase the accuracy of determining phase shifts between two harmonic signals of the same frequency.

3 dwg

 



 

Same patents:

FIELD: measurement equipment.

SUBSTANCE: phase meter comprises a facility of data collection and processing, a time setting facility and at least one signal processing channel. Each signal processing channel comprises serially connected analogue-digital converter and four registers. The inlet of the analogue-digital converter is the inlet of the phase meter and the inlet of the signal processing channel, the time setting facility by its inlets is connected to the clock outlets of the analogue-digital converter, four registers and the data collection and processing facility, outlets of the signal processing channel are connected to inlets of the data collection and processing facility. Two subtractors, a summator and two code doublers are introduced into each signal processing channel of this phase meter. Inlets of the summator are connected to the outlet of the analogue-digital converter and to the outlet of the fourth register, inlets of the first subtractor are connected to outlets of the first and third registers, inlets of the second subtractor are connected to the outlet of the summator and via the first code doubler to the outlet of the second register, the inlet of the second code doubler is connected to the outlet of the first subtractor, outlets of the signal processing channel are the outlet of the second subtractor and the outlet of the second code doubler.

EFFECT: device simplification.

2 cl, 2 dwg

FIELD: radio engineering, communication.

SUBSTANCE: synchronisable phase shift meter comprises two pulse formers, two frequency dividers, a synchroniser, XOR logic element and a time interval meter.

EFFECT: high efficiency of the phase shift meter owing to elimination of errors associated with violation of the order of arrival of input signals, and high accuracy of generating time intervals which define the desired phase shift.

5 cl, 3 dwg

FIELD: measurement equipment.

SUBSTANCE: Doppler phase meter of passive noise comprises a unit of phase evaluation, a unit of complex multiplication, a delay unit, a clock generator, the first multiplier, the first functional converter, the second multiplier, the second functional converter, the first memory unit, a complex summator, an additional phase calculator, the second memory unit, an additional unit of phase evaluation, the third and fourth functional converters, an additional unit of complex multiplication and an additional delay unit, which perform coherent processing of source counts with the purpose to measure trigonometric functions (cosine and sine) of current values of the Doppler phase of multi-frequency passive noise.

EFFECT: increased accuracy of measurement of Doppler phase shifts of multi-frequency passive noise.

9 dwg

FIELD: instrumentation.

SUBSTANCE: phase indicator of radio pulse signals contains delay unit, complex interface unit, complex multiplication unit, averaging unit, phase calculation unit, measurement limits correction unit, key, module calculation unit, threshold unit, memory unit, clock-pulse generator, first and second two-channel keys, additional averaging unit, control unit, additional delay unit, additional module calculating unit, additional complex interface unit, additional complex multiplier, summation unit, additional multiplier and additional memory unit, performing input reports processing between periods for unambiguous measurement of Doppler (radial) speed of the moving object.

EFFECT: possibility to receive the required range of unambiguously measured Doppler speeds upon keeping the unambiguous distance measurement.

11 dwg

FIELD: radio engineering, communication.

SUBSTANCE: method comprises using to analogue-to-digital converters (ADC) and two distributors of signal readings into even and odd readings to generate third and fourth signals from first and second signals by delaying the first and second signals by a fixed time interval, all products of even and odd signals, the first value as the difference between the product of the first signal and the third signal and the first signal and the fourth signal, the second value as the sum of the product of the first signal and the second signal and the third signal and the fourth signal and an estimate of the phase shift between the first and second signals as the arctangent of the ratio of time-averaged first and second values; generating fifth and sixth signals by delaying the third and fourth signals by a fixed time interval; generating the third value as the difference between the product of the first signal and the fourth signal and the product of the second signal and the third signal, the fourth value as the difference between the product of the third signal and the sixth signal and the product of the fourth signal and the fifth signal, the fifth value as the difference between the product of the first signal and the sixth signal and the product of the second signal and the fifth signal, the sixth value as the sum of the product of the first signal and the sixth signal and the product of the fifth signal and the second signal, the seventh value as the sum of the product of the first signal and the second signal and the product of the fifth signal and the sixth signal, the eight value as the difference between the square of the third value and the sum of the squares of the first and second values; generating the first value as the product of the fifth value and the square-root of the difference between four times the product of squares of the third and fourth values and the square of the eighth value and the difference between two times the product of the third, fourth and seventh values and the product of the sixth and eighth values, and generating the second value as the square of the difference between two times the product of the third, fourth and seventh values and the product of the sixth and eighth values.

EFFECT: reduced error when measuring phase shift of quasi-harmonic signals with slow-varying amplitude and frequency in the presence of additive and multiplicative interference.

4 dwg, 1 tbl

FIELD: radio engineering, communication.

SUBSTANCE: method includes generating a third and a fourth signal by delaying a first and a second signal by one interval, all products of even and odd signals, from which a first and a second value are generated, estimating the measured phase shift between the first and second signals as the arctangent of the ratio of time-averaged values of the first and second values; further generating fifth, seventh and ninth signals by delaying the first signals by two, three and four intervals, respectively, sixth, eighth and tenth signals by delaying the second signal by two, three and four intervals, respectively; generating a third value as the difference between the product of the second signal and the ninth signal and the product of the first signal and the tenth signal, a fourth value as the difference between the product of the fourth signal and the seventh signal and the product of the third signal and the eighth signal; generating a fifth value as the difference between the product of the fourth signal and the seventh signal and the product of the fifth signal and the sixth signal, a sixth value as the difference between the product of the third signal and the eighth signal and the product of the fifth signal and the sixth signal, a seventh value as the sum of the product of the fourth signal and the seventh signal and the product of the third signal and the eighth signal, an eighth value as the sum of the product of the third signal and the fourth signal and the product of the seventh signal and the eighth signal; wherein measurement is carried out in two steps, at the first step of which a first value is generated as the product of the fourth value and the sum of the fifth and sixth values and the square root of the difference between the square of two times the fourth value and the square of the third value, and a second value is generated as the product of the square of the sum of the fifth and sixth values and the sum of two times the fourth and third values; at the second step of which the first value is generated as the product of the magnitude of the fourth value and the difference between the product of the third and seventh values and two times the fourth and eighth values and the product of the square root of the difference between the square of two times the fourth value and the square of the third value, and the second value is generated as the square of the difference between the product of the third and seventh values and the product of two times the fourth and eighth values, and an estimate with the minimum mean-square deviation is selected from the phase shift estimates obtained at the first and second steps.

EFFECT: reduced error of measuring phase shift of quasi-harmonic signals with slow-varying amplitude and frequency in the presence of additive and multiplicative interference.

5 dwg

FIELD: measurement equipment.

SUBSTANCE: invention relates to measurement equipment and is designed to measure Doppler phase shifts (radial speed of an object) of coherent-pulse periodic radio signals on the background of noise; may be used in radar and navigation systems for unambiguous measurement of Doppler speed of aircrafts. The phase meter of coherent-pulse signals comprises a delay unit, a complex coupling unit, a complex multiplication unit, an averaging unit, a phase calculation unit, a unit of measurement limits correction, a key, a unit of module calculation, a threshold unit, a memory unit, a synchronous generator, an additional delay unit, an additional complex coupling unit, an additional complex multiplication unit, an additional multiplier and an additional memory unit, which perform the processing of initial counts between periods with the purpose of unambiguous measurement of Doppler (radial) speed of a moving object.

EFFECT: application of a phase meter of coherent-pulse signals makes it possible to produce required range of unambiguously measured Doppler speeds with preservation of unambiguous measurement of distance, which is the achieved technical result.

9 dwg

FIELD: measurement equipment.

SUBSTANCE: phase meter comprises the first input for the first signal equipped with the first analogue-digital converter, and the second input for the second signal, equipped with the second analogue-digital converter, identical to the first one, a time-setting device and a device of data collection and processing, at the same time the time-setting device with its output is connected to inputs of each analogue-digital converter and the device of data collection and processing, it also comprises identical first and second channels of signal processing, every of which comprises four serially connected registers, two subtractors and two summators with coefficients, the input of the first register in each channel is the input of the channel and is connected with the output of the appropriate analogue-digital converter, outputs of both summators with coefficients are outputs of channels and are connected with inputs of the device of data collection and processing, and their inputs are connected with outputs of each subtractor of its channel, inputs of the first subtractors of each channel are connected to the outputs of the first and third registers of this channel, and inputs of the second subtractors - with outputs of the second and fourth registers of this channel.

EFFECT: increased accuracy of a phase meter when measuring difference of signal phases having high-frequency bearing frequency.

2 cl, 7 dwg

FIELD: measurement equipment.

SUBSTANCE: invention relates to measurement equipment and may be used in radio engineering, metrology and other industries for precision measurement of phase difference of pairs of signals, and its variation in time. A phase meter with heterodyne conversion of frequency comprises a time-setting facility, the first and second identical analogue to digital converters, a facility for data collection and processing, besides, the time-setting facility is connected to the data collection and processing facility and each analogue to digital converter, which comprises the first digital multiplier and the second digital multiplier connected to the first analogue to digital converter, and also the third digital multiplier and the fourth digital multiplier connected with the second analogue to digital multiplier, connected to the second analogue to digital converter, the first digital conveyor low pass filter, connected with the first digital multiplier, the second conveyor low pass filter, connected with the second digital multiplier, the third digital conveyor low pass filter connected to the third digital multiplier, the fourth digital conveyor low pass filter connected to the fourth digital multiplier, at the same time each digital conveyor low pass filter is also connected to the facility of data collection and processing, and the time setting facility is connected to the first digital multiplier and the third digital multiplier.

EFFECT: higher accuracy of a phase meter in measurement of phase difference of signals having high-frequency carrier frequency.

2 cl, 2 dwg

FIELD: physics.

SUBSTANCE: digital method of measuring phase shift of harmonic oscillations under the effect of random perturbations is based on measuring in a limited time interval the average value of phase shift resulting from conversion of time intervals Δt between similar phases of measured and reference oscillations into the number of count pulses n on each the predefined m periods. The average number of count pulses is then measured in the sample median the variational series formed from volume sampling elements K=2k+1, (k=1, 2, 3…) of the count pulses on the time interval for measuring phase shift, where in all sampling elements, the number of periods of the measured harmonic oscillation is the same and equal to or less than m/k. The limited time interval includes m periods of the measured oscillation.

EFFECT: reduced errors in measuring phase shift of harmonic oscillations in a limited time interval with external effects on the measured signal.

1 dwg

FIELD: electrical engineering.

SUBSTANCE: method comprises measuring instantaneous values of sinusoidal voltage and nonsinusoidal current in the circuit. The power averaged over the period and effective values of voltage and current can be judged from the digital readings of instantaneous values of sinusoidal voltage and nonsinusoidal current in the circuit. The phase of the equivalent sinusoid is determined from the ratio of the power to the product of their effective values.

EFFECT: enhanced accuracy of determining.

3 dwg, 2 tbl

FIELD: measurement technology.

SUBSTANCE: analyzer should be used for measurement of statistic characteristics of random phase of signal. Analyzer has two conversion channels. Each channel has the following units connected in series: linear frequency-modulated signal generator, amplitude modulator, dispersion delay line, and demodulator with band-pass filter, multiplier, integrator and registrar. Output of demodulator of the first channel is connected with second input of second channel's multiplier. Output of demodulator of the second channel is connected through phase shifter with second input of multiplier of the first channel. Inputs of analyzer are connected with inputs of amplitude modulators through dividers. Other inputs of dividers are connected with outputs of amplitude modulators through threshold units and modulated signal power meters. Input signal frequency meter is connected with second input of analyzer. Output of frequency meter is connected with permanent storage through address decoder. Output of permanent storage is connected with input of threshold voltage unit. Output of threshold voltage divider is connected with second inputs of threshold units of any channel. Analyzer allows controlling signal level at output of amplitude modulator depending on frequency of input signal of analyzer to prevent over-modulation.

EFFECT: improved precision of measurement.

3 dwg

FIELD: electric engineering.

SUBSTANCE: method can be used to determine phase angle between sinusoidal signals of same frequency in one-phase circuit of alternating current during diagnostics of workability of electronic and electro-mechanical systems and devices. Signals are digitized for same time moments. Sum of current and previous counts of first signal and difference of current and previous counts of second signal are used to determine reactive quasi-power in time range, equal to signals period. Actual values of signals are determined. Phase angle between signals is determined from relation of reactive quasi-power to result of multiplication of actual values of signals.

EFFECT: no need for filtering constant component of signals and shifting signals for 90 degrees angle, also it is possible to achieve average error of phase shift calculation equal to 0,77%.

3 dwg, 2 tbl

FIELD: electric engineering.

SUBSTANCE: method can be used to determine phase angle between sinusoidal signals of same frequency in one-phase circuit of alternating current during diagnostics of workability of electric and electro-mechanical systems and devices. Signals are digitized for same time moments. Sum of current and previous counts of first signal and difference of current and previous counts of second signal for determining reactive quasi-power in time range, equal to signals period. Phase angle between signals is determined on basis of relation of reactive quasi-power to active quasi-power. In comparison to analogical solutions this method does not require filtering of constant component of signals and shift of signals for 90° angle and allows to achieve value of average error of determining phase shift equal to 0,24%.

EFFECT: higher efficiency.

3 dwg, 2 tbl

FIELD: technology for estimating time discrepancy occurring in two-channeled signal passing lines, for example, in stereo amplifiers.

SUBSTANCE: in accordance to first variant circuit has two-channel multiplexer, device for measuring time shifts and block for calculating estimates. Difference in group time of signals delay, coming in from outputs of tested amplifier, is measured by serial measurements of delay appearing in each channel of amplifier. In accordance to second variant circuit has delay line, connected to one of outputs of amplifier, time shift meter and estimate calculation block. Inserted delay is selected to be more than maximal possible difference of group delay time. Device for measuring time shifts can be a meter of time shifts of periodic signals, meter of time shifts of random signals, correlation meter of time shifts.

EFFECT: circuit requires no specially attached test signal generator and allows to perform measurements using any signal as test signal, spectrum of which lies within required frequencies spectrum.

2 cl, 4 dwg

FIELD: engineering of circuits for estimating time discrepancy, occurring in two-channeled signals passing routes, for instance, in stereo-amplifiers.

SUBSTANCE: circuit has two two-channeled multiplexers, outputs of which are connected to inputs of time shifts meter. Output of time shifts meter is connected to input of block for computing estimate of difference of group delay time. Inputs of one of multiplexers are connected to inputs of researched amplifier, and inputs of another multiplexer - to outputs of amplifier. Difference of group signals delay time, signals coming from outputs of tested amplifier, is measured by means of alternating measurements of delay, appearing in each one of amplifier channels. In accordance to second variant in the circuit outputs of time shifts meter are connected to outputs of multiplexers through two identical filters. Time shifts meter can be correlation meter of time shifts.

EFFECT: circuit makes it possible to perform measurements using any random signals as test signals, spectrums of which lie within target frequencies range, independently for each channel.

2 cl, 3 dwg

FIELD: information processing systems, applicable at control of the electric power line on the basis of its adaptive model readjusted according to the current information on the power line electric parameters.

SUBSTANCE: the method consists in the fact that simultaneous determined are the current values of voltage and current respectively at the beginning and end of the line, each digital readout, both the present and the previous ones, are is conserved, then simultaneously determined are the reactive power at the beginning of the power line and the reactive power at the end of the power line and reactive quasi-power and then current reading of the signals are multiplied and determined their active power at the beginning of the line and the active power at the end of the line are determined, active quasi-powers and are determined, on the basis of which determined are the angles of divergence of vectors between voltage and current at the beginning of the power line, between voltage and current at the end of the line, as well as the angle of divergence of vectors between voltage at the beginning of the power line and between voltage at its end, and the angle of divergence of vectors between current at the beginning of the power line and between current at the end of the line.

EFFECT: simplified, enhanced precision and information content of determination of the current electric parameters of the power line.

4 dwg, 3 tbl

FIELD: engineering of informational and transformation equipment when used as primarily intended, and may be used as primarily intended and during realization of functional transformers, angle meters, etc.

SUBSTANCE: one-channel infra-low-frequency filter contains multiplexers, subtraction block, division block, phase shifters, block for transformation of inverse tangent, block for generation of correction value, commutator, counting-registering block, block for determining correction value and control block.

EFFECT: increased precision of measurements due to introduction of corrections to result of measurement, allowing to exclude ambiguousness of determined phase shift of sinusoidal signals.

1 dwg

FIELD: electric measuring technique.

SUBSTANCE: method can be used for automatic correction of angle error of current transformers, particularly, electric energy electron meters. Method is based upon measurement of instant values of input current and voltage signals as well as angles φ among them. Correction of angle error of tested current transformer is performed on base of measurements. Electric energy meter is graduated, which meter has current transformer to be tested, by means of connecting meter to assembly for graduation of meters at power coefficient being equal to cos(φ)=1. Then power coefficient being equal to cos(φ)=0,5L is preset in assembly for graduation of meters, and relative error δ1 of meter is measured. Then power coefficient being equal to cos(φ)=0,5C is preset at assembly for graduation of meters and relative error δ2 is measured. After that the relative error of meter, which error was induced by angle error δ of current transformer, is calculated. On base of measured value of relative error δ of meter the value of sine of angle error sin(Δφ) of current transformer is calculated. Correction coefficient is calculated on base of calculated value of sin(Δφ). Precision of measurement of meters is improved due to simplified calculations of angle error of current transformer and due to introduction of automatic correction of angle error of current transformer.

EFFECT: improved precision of measurement.

4 cl, 1 dwg

FIELD: the proposed invention refers to the field of measuring statistical characteristics of random processes and may be used for measuring statistical characteristics of the random phase of a signal.

SUBSTANCE: the task of this invention is in expanding functional possibilities of the arrangement and simplification of the procedure of measuring density of probability of the phase. The analyzer of density of probability of the phase of the signal has an accounting block with memory, an analog storing block, a former of supporting vibration, a control generator, a former of gating impulses, two transformation channels in each of which there are included a selection and storing block, two transformation channels. In each of them there is a selection and storing block, an analog-digital converter and an accumulative averaging adder. Besides the arrangement has additionally the first and the second multipliers, the first and the second functional converters, an operative adder, an additional accumulative adder and separately a control block correspondingly connected between them.

EFFECT: expands functional possibilities of the arrangement.

3 dwg

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