SU543889A1 - Digital period meter - Google Patents

Description

(54) DIGITAL PERIOD MEASUREMENT

one

The invention relates to a radio measuring technique and can be used to measure the period of harmonic signals.

A digital period meter is known, which contains an exemplary frequency generator that forms a block, an output connected to the input of a reversible counter, the second input of which is connected to the output of the control unit, the output to the input of the last, and the other outputs connected to the inputs of a summing counter consisting of triggers and delay lines.

The disadvantage of this device was the lack of speed.

The purpose of the invention is to increase speed.

To achieve the goal in a digital period meter, which contains an exemplary frequency generator, a forming unit, an output connected to the input of a reversible counter, the second input of which is connected to the output of the control unit, the output to the input of the latter, and the remaining outputs via electronic keys are connected

to the inputs of a summing counter consisting of triggers and delay lines, the summing counter is equipped with OR elements and matching blocks, the output of each of which is connected to the input of the corresponding OR element through a corresponding delay line, the second input of which is connected to the second input of the latter and the output of the corresponding electronic key, and the output of each element OR is connected to the input of the corresponding trigger and the output of the generator of the reference frequency - with the second inputs of the electric these keys.

The drawing shows a diagram of the device.

The digital period meter consists of a shaping unit 1, a reversible counter 2, a generator of exemplary frequency 3, electronic switches 4g-7, a summing counter B consisting of triggers 9-12, delay lines 13, 14 and 15, elements 16, 17 of coincidence and elements 18, 19, 2O, control device 21.

The output signal arrives at the shaping unit 1, at the output of which a stream of pulses is formed, corresponding to the moments of the input signal passing through the zero level. These pulses arrive at the input of the reversible counter 2. When the first impulse of the input signal arrives at the reversible counter, open the key 4, and the pulses from the generator 3 of the model part start to arrive at the first trigger 9 of the summing counter 8. Thus, the result kvan will be recorded in counter 8 tirovani the first period with a weight equal to one. During the second period of the input signal, the triggers of the reversible counter become 010OO ..., the key 4 is closed, and the key 5 is open, and the second trigger 10 of the summing counter 8 is started through the element 18 OR the quantized result of the second period of the input signals, they will be counted summing counter with a weight equal to two. During the third period of the signal under investigation, the state of the triggers of counter 2 will be 11OOO ... Keys 4 and 5 are opened and quantizing pulses begin to flow to counter 8. To prevent the pulses at the input of the second trigger Yu of the summing counter 8 to coincide, the pulses from the first trigger 9 are delayed the delay line 13. As a result of operation of keys 4 and 5, summing counter 8 will accumulate the result of the third period quantization, the input signal with a weight equal to three.

To prevent the output of the remaining triggers from coinciding with the pulses from the outputs of the triggers Yu, 11, 12, and keys 6, 7 noafofyfcsT to the match analyzer, consisting of 16, 17 ln matching elements 14, 15 delays, and 19, 2O OR elements.

The analyzer operates as follows: BelFl Tuple sequences not with & . t

fall, they pass through element 19: OR and Chuchaktsts flip-flops (11 times adequately. When pulses coincide, they are counted by flip-flop 11 as a single pulse, but at the same time a coincidence element 16 and a lost pulse are triggered through LRT 14 delay and element 19 OR blunts on the trigger 11 of the summation counter 8. This eliminates the error due to the coincidence of the pulses in the simultaneous operation of several keys. The component of the total mean square error due to the quantization error is small. It can be used in the frequency measurement mode. To switch to this mode, you need to swap blocks 1 and 3.

Fbrmula invention

A digital period meter that contains an exemplary frequency generator that forms a block, an output connected to Bxot a reverse meter, the second input of which is connected to the output of the control block, an output to the input of the last one, and the remaining outputs through -n electronic keys consisting of triggers and delay lines, characterized in that, in order to improve speed, the summing counter is equipped with OR elements and matching blocks, the output of each of which is The delayed linsho is connected to the input of the corresponding OR element, the second input of which is connected to the input of the matching block, and the third to the second input of the last and to the output of the corresponding electro key (and the output of each OR element is connected to the input of the corresponding trigger, and generator output, figurative frequency - with the second inputs of electronic keys.

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