SU598231A1 - Single band signal shaper - Google Patents

Description

The invention relates to electrical measuring equipment of the infra-low and sound frequency ranges and can be used in designing equipment for biophysical, acoustic, geophysical, etc. research. Devices are known for generating a single-band signal by a phase-compensation method, comprising two annular modulators and output transformers with serially connected output windings l. The disadvantage of this device is the high criticality of the circuit to the amplitude characteristics of the modulators. Of the known devices, the closest in technical essence is a device for generating a single-sided signal, consisting of frequency multipliers of the original signals, shapers of short pulse sequences, which are added by the OR element and fed to the input of the trigger frequency divider, from the output of which a single band JD signal is taken. A disadvantage of such a device is the ambiguity in the phase of the output signal, which leads to a decrease in the measurement accuracy. This is due to the use of a frequency divider to form a single band signal. To any possible stationary value of the initial phase of the output oscillation of the frequency divider (with the division factor W), there are still -1 -1 possible values of the initial phases, each of which differs from the neighboring one by 211 / M. The phase ambiguity of the output signal of such a device leads to the uncertainty of the results of phase or phase-sensitive measurements performed by the system, which includes the complete device as an integral part. So, if N 4, then the phase angles are determined with an error of ± с ft / 2 (1 О, 1, 2), and instead of, for example, the real signal component, the imaginary component can be mistakenly measured, etc. The purpose of the present invention is to improve the measurement accuracy. This goal is achieved by the fact that the proposed device for. generating a single band signal for phase measurements in the infra-low and sound frequency ranges, containing

sources of carrier and operating frequencies, each of which is connected via two serially connected frequency doublers to the inputs of the assembly, the output of which is connected to the input of a frequency divider of two triggers, are introduced an analog instantaneous multiplier, the first input of which is connected to the operating frequency source directly, the second the input is through the element NOT, and the third and fourth inputs are connected to the outputs of the second trigger of the frequency divider, two elements OR, three elements AND, and an additional element NOT, the output of which is connected to the input of the first element I, and the input is connected to the connection point of the first input of the third element I, the output of one and the input of the other doubler of the operating frequency, and the second input of the third element I is connected to one output of the first trigger of the frequency divider and to the other input of the first element I whose third input is connected to one output of an analog multiplier of instantaneous values, and the output is connected to the input of the second OR element, the output of which is connected to the third input of the assembly, the second input is connected to a signal source esuschey frequency, and a third input coupled to an output of the second AND gate one input of which is connected to the output of the analog multiplier s.vtorym instantaneous values, and the other input, connected via a first OR-zlementy, to the second output of the first flip-flop frequency divider and to the output of the third element I.

FIG. Figure 1 shows the structural electrical circuit of the device proposed; Fig. 2 shows the time diagrams of the voltages that illustrate the operation of the circuit.

A device for forming one. band signal consists of carrier frequency doublers 1 and 2, operating frequency doublers 3 and 4, assembly 5, a frequency divider consisting of two triggers 6 and 7, first, second and third elements AND 8-10 respectively, first and second elements OR 11 and 12, analog multiplier. 13 instantaneous values, two elements NOT 14 and 15, a source of 16 operating frequency signals and a source of 17 carrier frequency signals.

From sources 16 and 17 of the working and carrier frequency signals, respectively, a series of unipolar rectangular impulses of the working L “are received at the device input. intermediate O) frequency (figure 2, a and b, respectively). Doublers 1-4 double the frequencies of the signals fed to their inputs and form the sequence of the pulses 1 -I-Ln 2 1 5u.1d),

And 1 + ln 4 u) l (Fig. 2), - and 5 1 + + Ln2L1 (Fig. 2, c), 1G4 - 1 Ljr4L1 (Fig. 2, d), where ir,, U, and and voltages from the outputs of the respective frequency doublers. Positive drops 2 and 4 are distinguished by differentiation, summed by assembly 5 (Fig. 2, g) and fed to the input of a frequency divider consisting of a trigger b.

FIG. 2, 3 and k are shown, for example, from the output of the trigger 6 of the frequency divider, and in FIG. 2, and the voltage shown is the voltage output from the trigger 7 of the frequency divider, the voltages shown in FIG. 2, and l is the desired single-band signal, for example, in the upper sideband

The plots of the single-band signal are shifted along the time axis depending on the initial state of the frequency divider cells (at t 0). So, if with both triggers the frequency splitter is in the zero state, then the timeline of the single band signal corresponds to FIG. 2, and. If, on the other hand, a different initial state of the frequency divider cells is taken, then a single sideband signal shifted in time is equivalent to a phase shift. Consequently, a single band signal generated by a device with a frequency divider is ambiguous in phase, and all possible values of the steady state phase of a single band signal correspond to the same sinal (fig. 2, g) j the exciting frequency divider and, consequently, the same initial signals working (Fig. 2, d) and intermediate (Fig.2, b) frequencies.

The way to eliminate the phase ambiguity of a single band signal is to use the signals of the trigger 6 and frequency divider 7, as well as the output voltages of frequency multipliers 1-4 in the signal conversion path, for example, the operating frequency (Fig.2, a) and the recovery of the carrier signal (intermediate) frequency, and the phase of this signal is determined by the initial state of the triggers 6 and 7 of the frequency divider.

Claims (2)

If, when comparing the phase of the recovered and the original carrier frequency signals, the phase shift between them is not equal to the predetermined value, the analog multiplier 13 instantaneous values gives 5 additional pulses to the assembly. With their help, the required initial state of the triggers 6 and 7 of the frequency divider is established, at which the output signal of the analog multiplier 13 disappears, and the desired single-band signal is synchronized with the original signals of the working and carrier frequencies. The formation of a sequence of additional pulses that shift the phase of a single band signal, produces with the following. . First, the analog multiplier 13 multiplies the signals from the trigger 7 (Fig. 2, and l) and the original signal of the operating frequency (Fig. 2, a). From the output of this clever inhabitant, the signal shown in FIG. 2 minutes . Signals from trigger 6 (Fig. 2, g and c) are passed through AND 10 element (Fig. 2, o) and OR element 11 (Fig. 2, p). Next, the output voltage from the element OR 11 (FIG. 2, p) is multiplied by a signal And 9 by a signal (FIG. 2, an analog multiplier 13, as a result of which the output of the And 9 element receives the signal shown in FIG. 2, p Element And 8, in turn, multiplies the output voltage of the trigger b of the frequency divider b (Fig. 2, h), the inverted signal of the first operating frequency doubler 1. (Fig. 2, c) and the signal from the analog multiplier 13 ( Fig. 2, n.) From the output of the AND 8 element (Fig 2, t), the signal goes to the OR 12 element, where the addition is performed the bottom of the carrier signal (Fig. 2, b) and output voltages of the elements And 8, and the output voltage of the element OR 12 (Fig. 2, y) applied to the assembly 5 is the timing signal, the first positive differential of which Impact on the assembly causes the formed single-sided signal to be shifted in phase by the angle ift / 2 and the change; the initial state of the triggers 6 and 7 d power of the frequency This shift occurs until the initial state of the triggers 6 and 7 frequency dividers is reached, where the output signal of the element OR 12 is equal to the constant and does not contain voltage drops, which, through assembly 5, act on the frequency divider and cause the shortest change in the state of the incoming triggers b and 7. In this way, a single-band signal is formed that is synchronized with the system of the original working and carrier frequency signals. In the future, at possible failures in the operation of the device, synchronism is restored automatically. Formula of the Invention A device for generating a single-pole signal for phase measurements in the ranges of infra-low and sound frequencies, containing sources of carrier and working frequencies, each of which is connected via two serially connected frequency doublers to the inputs of the assembly, the output of which is connected to the input of a frequency divider of two triggers , characterized in that, in order to improve the accuracy of measurements, an analog instantaneous multiplier is introduced in it, the first input of which is connected to the signal source frequency directly, the second input through the NOT element, and the third and fourth inputs are connected to the outputs, the second trigger of the frequency divider, two OR elements, three AND elements and an additional NOT element, whose output is connected to the input of the first And element, and the input is connected to the junction point the first input of the third element And the output of one and the input of the other doubler of the operating frequency, the second input of the third element And is connected to one output of the first trigger of the frequency divider and to another input of the first element And, the third input is go is connected to one output-analog instantaneous value multiplier, and the output is connected to the input of the second element OR, the output of which is connected to the third input of the assembly, the second input is connected to a source of carrier frequency signals, and the third input is connected to the output of the second element And, one input connected to the second output of the analog instantaneous value multiplier. And the other input is connected via the first element OR to the second output of the first trigger of the frequency divider and to the output of the third element I. Sources of information received in o attention in examination: 1. Meinke: x. {and Gundlakh f. Radio Handbook Vol. N, ML., About Gosenergoizdat, 1962, p. 386, fig. 21-59. 2. Author's certificate V259266, n 03 K 7/00 06/15/68 output a) S) and) “; 3) ); 3) and) ") f)) ) f) R) with)