SU1499275A1 - Method of measuring duration of pulses of periodic pulse sequence - Google Patents

Abstract

The invention can be used to measure the duration of arbitrary pulses at a standard relative reference level (half amplitude level) when monitoring generators having direct and inverse outputs of a signal of the same amplitude and polarity using a frequency meter having a block for measuring time intervals. The purpose of the invention is to reduce hardware costs-achieved by eliminating frequency and voltage measurements. According to the measurement method, in order to control by the level of half the amplitude of the pulse duration, it is necessary to measure the pulse width (pause) of the direct pulse sequence at a certain reference level, measure the length of the pause (pulse) of the inverse (logical inversion) pulse sequence having the same amplitude and polarity, on the same level of reference, compare the values of the measured values of time intervals, with the inequality of the values of the compared values of time intervals, change the reference level until and equality of achieving equal values compared values stop changing the reference level and to fix the measured value of balanced time slots as the required value of the pulse duration. 1 il.

Description

one

The essence of the method is that the property of equality of the pulse durations of the direct (t,) and pauses of the inverse () pulse sequence (having the same amplitude and polarity) between themselves at the level of half of the amplitude (c) is used. This property is proved as follows. Denote by f (t) the direct pulse sequence normalized to the amplitude U ,.

Then the level of intersection of the superimposed direct and inverse pulse sequence signals (c) can be easily determined from the equation

 (t); 0.5

)

f (t)

Therefore, it is equal to the level of half amplitude, and regardless of the pulse shape, and the equality of the impulse impulses of the direct and pauses of the inverse pulse sequence is achieved at this level.

The operations (features) of the method are known per se and are easily implemented by standard measuring means, in particular, using a time meter of a standard frequency meter.

To control the half amplitude level of the pulse duration produced by the generator, which have direct and inverse signal outputs of the same amplitude and polarity, according to the method it is necessary: measure the pulse width (pause) of the direct pulse sequence at a certain level of reference U (a); measure the duration of the pause (pulse) inverse. (logical inversion) im-. pulse sequence having

that

same amplitude and polarity, at the same level of reference U (b); compare the values of measured values of time intervals; if the values of the compared values are not equal, change the reference level until equality is achieved; when the values of the compared values are equal, stop changing the reference level and record (register, record) the measured value of the balanced time intervals, as the desired value of the pulse duration of an arbitrary shape at the standard relative reference level (half amplitude, c).

Claims (1)

Invention Formula A method for measuring the pulse duration of a periodic pulse sequence, including measuring time intervals, is carried out in order to increase the accuracy in monitoring arbitrary pulse generators having direct and inverse outputs of signals of the same amplitude and polarity, and compare the duration of the pulse (pause) of the direct pulse sequence with the duration of the pause (pulse) of the inverse pulse sequence at the same arbitrary level of reference, pr than in the case of inequality of the compared values of the quantities varied reference level to achieve equality, then stopped changing reference level u d .telnosti pulses and record the measured value of the duration of balanced time slots as the required value of the pulse width at half amplitude.