RU1812514C - Device for digital measurement of frequency - Google Patents

Abstract

The invention relates to electro-radio measurements and can be used to determine the frequency in adjacent time intervals without loss of information. The aim of the invention is to simplify the device. A digital frequency measuring device comprises a pulse generator of the measured frequency, an AND element, a counter of the measurement result, a memory unit, an exemplary time interval generator, and an I. element. The introduction of a control counter allows simplifying the implementation of the device. 2 ill.

Description

The invention relates to the field of electro-radio measurements and can be used to determine the frequency in adjacent time intervals without loss of information.

The purpose of the invention is to simplify the device.

. In FIG. 1 is a structural diagram of a device; in FIG. 2 are timing diagrams illustrating its operation.

The digital frequency measuring device comprises serially connected pulse generator 1 of the measured frequency, element AND 2. counter 3 of the measurement result and a memory unit 4, as well as a generator 5 of an exemplary time interval, element And 6, and a control counter 7. The first and second outputs of the counter 7 are connected, respectively, with the input of the census of the memory unit and the installation input in the initial state of the counter 3 of the measurement result, and the third output of the counter 7 is combined with the second input of the element And 2 and the inverse input of the element And 6, the input of which is connected to the input of the element And 2. Counting input and installation input to the original

the state of the control counter 7 is connected, respectively, to the output of the And element 6 and the output of the driver 5 of the exemplary time interval.

A digital frequency measuring device operates as follows.

The counting stop signal (Fig. 2c) is generated from the start pulse of the reference time interval (Fig. 26), for which the driver 5 gives a short pulse at the beginning of each reference time interval, which sets the counter 7 to its initial state. From this moment, measurement begins, i.e. the passage of pulses from the former 1 through the And 2 element to the input of the counter 3 is prohibited, and the passage of these pulses through the And 6 element to the counting input of the counter 7 is allowed (Fig. 2c), at the outputs of which control signals are sequentially generated:

- at the first output (Fig. 2d) - a signal for rewriting the measurement code from the counter 3 to the memory unit 4 for storing the previous frequency measurement result;

- at the second output (Fig. 2e) - signal to set the counter 3 to its initial state;

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- at the third output (Fig. 2c) - a signal that stops the operation of the counter 7 and allows the passage of pulses from the output of the driver 1 through the element And 2 to the input of the counter 3 (Fig. 2E). The signal at the third output of counter 7 is maintained until the start of the next exemplary time interval.

The number of measured frequency pulses transmitted to the counter 7 during the stop of the counter 3 is taken into account in the initial state of the counter 3 (in Fig. 2 the number of these pulses is equal to two).

Thus, the device provides the generation of signals for storing the measurement result (Fig. 2d) and for setting the circuit to its initial state (Fig. 2e) while counting is stopped from the pulse train of the measured frequency (Fig. 2a).

The device can also be used to measure the period. In this case, the shaper 5 generates short pulses at the end of the measured period, and the shaper 1 generates a pulse sequence from the reference frequency, so the signals at the outputs of the counter 7 are generated from the pulses of the reference frequency.

Thus, the described single-channel device with its relative

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simplicity provides a frequency measurement at adjacent intervals of the reference time interval without loss of information.

Claims (1)

The claims A digital frequency measuring device comprising a pulse generator of the measured frequency connected in series, a first I / I element, a measurement result counter and a memory unit, the output of which is the output of the device, as well as an exemplary time interval generator and a second AND element, the input of which is connected to the input of the first element And, in that, for the sake of simplification, a control counter is introduced into it, the first and second outputs of which are connected respectively to the input of the census of the memory unit and the input of the installation to the initial state of the counter of the measurement result, and the third output is combined with the second input of the first element And and the inverse input of the second element And, while the counting input and the input of the installation in the initial state of the control counter are connected respectively to the outputs of the second element And and the shaper of the reference time interval . FIG. 1 - LLLP ... LLLSH ... LH FIG. 1