SU134491A1 - Electronic correlograph for automatically calculating and recording the correlation function of a stationary random process - Google Patents

Description

Electronic correlographs are known for automatically calculating and recording the correlation function of a stationary random process recorded on a ferromagnetic tape.

The described electronic correlograph differs from the known ones in that it uses a blocking device and a system for compensating for mutual phase shifts between channels. This made it possible to eliminate the occurrence of errors arising from the removal of signals at times when the tape was glued together by magnetic heads, and to increase the calculation accuracy.

FIG. 1 shows a diagram of blocking its device; in fig. 2 (a and b) is a block diagram of recording and playback that explains the operation of the compensation system.

The process was recorded on a ferromagnetic tape with a two-channel tape recorder, in which the frequency modulation of the carrier frequency of the signal under study was applied. The studied recording area is glued together in a ring and repeatedly and continuously reproduced in a tape recorder of a correlograph. In order to avoid a false reference at the moment of time, the discontinuity of the continuity of the function is located between the magnetic heads, a locking device is used, consisting of a standby multivibrator /, a polarized relay 2 and a contact group 3.

The pulse width of the multi-vibrator is set using potentiometer 4 to be slightly longer than the maximum time value.; Support t ,,,,. When a triggering pulse is applied, the polarized relay connected between the anodes of the multivibrator lamp disconnects the integrating device for the blocking time t, 1.2 t "k. The normal operation of the blocking circuit is detected by a neon lamp 5.

No. 134491-2 Contact group 5 is located in a tape device (not shown in the drawing). Two flexible contacts of this group relate to the outer surface of the ferromagnetic tape, on which a strip of copper foil is glued in a certain place. When the strip passes through the contact group, the circuit is knocked off, and a starting pulse is supplied to the "input of the multivibrator", which is previously differentiated on the string 6.

To improve the accuracy of the calculation, a system for compensating for mutual phase shifts between the channels of a tape recorder was applied, for which, when the recording goes to playback, the channels mutually alternate with the signal transmission paths. The signal under study is fed to the input to the recording equipment 7 and S, then the signal passes through the low-pass filters 9 to the inputs of the frequency-modulated oscillators 10. The W-oscillators are used in the auto-oscillation mode as W generators. Then the voltages of the frequency modulated hen, they are sent to universal magnetic heads 11. When recording in the first channel after filter 9, a phase shift of the signal being measured is created in the second AF-AF. When playing, the voltage of PM is M. Nesush, their output goes from the universal heads to the preamplifiers 12, then through the limiting amplifiers 13-to the rectangular pulse shaping circuit 14, consisting of the waiting multivibrator: These pulses having a constant amplitude and modulated in frequency by the signals under study, fall on the inputs of frequency discriminators 15. The reproduced signal of the first channel is output through a plug-in low-pass filter 9, the reproduced signal of the second channel through its filter 9. Thus, the signals reproduced at the outputs of both channels have the same resulting phase shifts equal to Lf1 + Dfg, and the mutual phase shift between the output voltages is compensated.

 I p e d. M et and 3 about b and e and

1. Electronic correlograph for automatic calculation and recording of the correlation function of a stationary random process recorded on: ferrom, agnit, tape using a two-channel tape recorder, in which the frequency modulation of the carrier frequency is applied, based on reading the instantaneous value of the random variable from the ferromagnetic one. tape, characterized in that, in order to eliminate false readings at the point in time when the place where the tape was glued, where there is. The discontinuity of the recording is between the magnetic E heads employed therein locking device.

2.Electronic correlograph of section 1, characterized in that, in order to improve ACCURACY: computation, it is equipped with a system for compensating for mutual phase shifts between channels.

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Fig

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Fig 2a