SU1208515A1 - Apparatus for measuring frequency deviation - Google Patents

Abstract

The invention relates to a device for measuring the frequency deviation of frequency-manipulated signals. The purpose of the invention is to improve the measurement accuracy and speed of the device. The goal is achieved as a result of the device forming its own measuring interval for each of the frequencies of the input frequency-manipulated signal, while their durations are fixed by a certain number of periods of the corresponding frequency and are multiples of the whole number of these periods. As a result, it is the durations of the measuring intervals that are measured, which is accomplished by filling the intervals with pulses of the reference frequency generator. The operation of the device is explained in the description of the invention by the functional diagram of the device and timing diagrams. 2 3.p. f-ly, 2 ill. sl y oh sh

Description

The invention relates to electrical and radio measurements and is intended to measure the frequency deviation of frequency-manipulated signals.

The purpose of the invention is to increase the measurement accuracy and speed of the device.

The goal is achieved by the fact that the device forms its own measuring interval for each of the frequencies of the input frequency-manipulated signal, and their durations are fixed by a certain number of periods of the corresponding frequency and are multiples of the whole number of these periods. In this case, it is the durations of the measuring intervals that are measured, which is carried out by filling them with the pulses of a reference frequency generator,

Figure 1 shows the block diagram of the device; 2 shows timing diagrams explaining its operation.

The device contains a discriminator of I manipulation frequencies, the input of which is connected to the input of the device, the first 2 and second 3 time interval drivers, each of which consists of series-connected coincidence element 4; and counter 5. The device also includes the first 6 and second 7 elements And, the first inputs of which are connected respectively to the outputs of the first 2 and second 3 time formers of the summation and control unit 8, made on the basis of the reversible counter 9, generator 10 the reference frequency and the digital indicator I ,, information inputs and rewriting input of which are connected to the corresponding outputs of the summation and control unit 8. In addition, the device has a trigger 12; the first and second inputs of which are connected: to the second outputs of the corresponding formers of 2 and 3 time intervals, the first inputs of which are connected to the input of the device, and the second inputs to the first and second outputs of the manipulation frequency discriminator, respectively. Elements 6 and 7 are equipped with third inputs, and their second inputs are connected respectively to the first and second outputs of the trigger 12, their third inputs are connected to

ten

213

thirty

4CI

45

15 ,

the output of the reference frequency generator 10, and their outputs are connected respectively to the first and second inputs of the summation and control unit 8, the third input of which is connected to one of the outputs of the trigger 12. The fourth and fifth inputs of the summation and control unit 8 are connected to the first outputs, respectively the first 2 and second 3 time interval drivers, the first inputs of which are connected to the sixth input of the summation and control unit 8, the seventh input of which is connected to the device Start terminal, and its installation output to the corresponding them to an input of time slots 2 and 3, mounting the inputs of which are the second inputs of counters shkov 5, the output of the second time slots each are connected to the output element 4 of its coincidence.

The summation and V-etching unit includes an element AND 13 and a trigger 14, the output of which is connected to the installation input of the reversible counter 9, the first, second and control inputs of which are the first, second and third inputs of the summation and control B, respectively. from the fourth to the seventh of which are formed respectively by the inputs of the element AND 13 and the inputs of the trigger 1-4, the output of which is connected to the installation output of the summation and control unit 8, the information outputs of which are the output busses reversible counter 9 and dubbing output - the output of the AND 13.

To ensure the processing of the continuous frequency-manipulated signals, the device may contain a shaper 15 of the input signal, the input of which is connected to the input of the device, and the output to the first inputs of shaper 2 and 3 time intervals.

The device works as follows.

A frequency-manipulated signal is fed to the input of the device, which in the shaper 15 of the input signal is converted into a sequence of pulses 16. The discriminator of the frequencies of manipulation 1 generates a signal 17, the shape of which

corresponds to the shape of the modulating signal.

The measurement cycle starts at the moment when the signal appears. A start is started at the corresponding terminal of the device. This signal sets trigger 14 to one state. The trigger 14 returns to the zero state with the first impulse from the output of block 15. Thus, a rectangular pulse 18 is formed at the output of trigger 14, the leading edge of which sets the counters 5 of blocks 2 and 3, as well as the reversible counter 9 to the zero state.

The pulses from the output of block 15 from one of the frequencies f, the input signal is fed to the counter of the first time interval shaper, and the pulses corresponding to the second filling frequency fj are recorded by the counter of the second time slot fi 2-20 and 2-20. In this case, at the second outputs of blocks 2 and 3, bursts of pulses of the corresponding frequency are formed (f, and f2). The first pulses of these packs put the trigger 12 into the state in which the corresponding element AND is opened, and the other element closes 2. As a result, the first input of the reversible counter 9 receives pulses from the generator output 10 of the reference frequency only during the pulse frequency interval f, and to the second input of the reversible counter - only on the pulse pulse interval with a frequency. The reversible counter is controlled by a signal at its control input (this signal is generated at one of the outputs of the trigger 12 so that it operates combining mode into the interval f (mode and subtracting the interval fg.

After both counters 5 are filled to the set value W, they are blocked and the corresponding elements 6 and 7 are locked. And at the output of the element 13 there is a signal that carries the code recorded on the reversible counter and reflecting the value frequency deviation

input signal. I

The value of the N code on the reverse

counter to the end of the measurement cycle op15

determined by the ratio (f is the frequency at the output of block 10

N nf „(- - {),

L, 1 2

from which you can get the value of the frequency deviation uF f f

The Start signal, which determines the beginning of the measurement cycle, can be received from outside the device, or it can be generated automatically by the end signal of the next measurement cycle.

Claims (3)

Invention Formula 15 A device for measuring the frequency deviation, containing a frequency discriminator of manipulation, the input of which is connected to the input of the device, the first and second time interval formers, each of which consists of a series-connected coincidence element and a counter; in addition, the device includes first and second AND elements, the first inputs of which are connected respectively to the first outputs of the first and second time interval formers and the summation unit and control, made on the basis of a reversible counter, a reference frequency generator and a digital indicator, information inputs and rewriting input of which are connected to the corresponding outputs of the summation and control unit, characterized in that, in order to improve the measurement accuracy and speed of the device, a trigger is inserted into it, and the second inputs of which are connected to the second outputs of the respective time formers, the first. inputs which are connected to the input devices, and the second inputs - to the first and second outputs of the frequency manipulator, respectively, the elements And are equipped with third inputs, and their second inputs are connected respectively to the first and second outputs of the trigger, their third inputs - to the output of the reference frequency generator, and their outputs are connected respectively to the first and the second inputs of the summation and control unit, the third input of which is connected to one of the trigger outputs, its fourth and fifth inputs S connected to the first outputs of the first and second time formers, respectively, the first inputs of which are connected to the sixth input of the summation and control unit, the seventh input of which is connected to the device Start terminal, and its installation input is connected to the corresponding inputs of the time formers, the installation inputs of which are the second inputs of the counters, with the second outputs of the time formers each connected to the output of their coincidence element. 2. The device according to claim 1, characterized in that the element And the trigger, the output of which is connected to the installation input of the reversible counter, is introduced into the summation and control unit. 085156 the second and control inputs of which are respectively the first, second and third inputs of the summation and control unit, the inputs The fourth to seventh IJ are formed, respectively, by the inputs of the element I and the inputs of the trigger, the output of which is connected to the installation output of the summation unit and 10 control, the information output of which is the output of the reversible counter, and the output of the rewrite is the output of the element I. 3. A device according to n.i, about tl and 15 such that, in order to ensure the processing of uninterrupted frequency-manipulated signals, an input driver is inputted into it, the input of which is connected to the input of the device, and the output is connected to the first inputs of time formers, BUT,, f .- / 1 I I I I I I I I I I I I I I / 71 I a / n t shshshshshshsh Ofig. 2