SU1432424A2 - Device for checking amplitude-frequency characteristics - Google Patents

Abstract

The invention relates to techniques and measurements. The purpose of the invention is to improve the accuracy of bandwidth monitoring. The device contains an input terminal 1 of the device, a filter unit 2, a reference frequency signal detection unit 3, a memory block 4, a voltage level adjustment unit 5, a comparison unit 6, a control frequency signal detection unit 7, an 11PI element 8, a key 9, a display unit 10 , the trigger driver 11 for switching voltage, the trigger generator 12 for time, the trigger generator for 13 control voltages. Voltage level normalization unit 5 is made in the form of n channels, each of which contains serially connected channel switch 14, level normalization element 15, and OR elements 16, 17. Introducing additional inputs of the voltage level regulating unit, which are connected to the corresponding outputs of the signal detection unit It allows monitoring the signal level in the passband at n frequencies, and not only at the edge frequencies of the passband. 2 Il. S ate

Description

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The invention relates to a measurement technique and is an improvement of the device according to the author. № 1250987

The aim of the invention is to improve the accuracy of bandwidth monitoring.

FIG. 1 shows the flow chart of FIG. 2 - temporary diagrams that show the operation of the device.,

: 3 | The device contains an input terminal 1, a filter block 2, a reference frequency signal detecting unit 3, a memory block 4, a voltage level regulation block 5, a comparison block 6, a control frequency signal detecting block 7, the first element OR 8 a key 9, the display unit 10, the switching voltage trigger 11, the time trigger 12, and the control voltage trigger 13. The voltage level normalization unit 5 is made in the form of n channels, each of which contains serially connected channel key 14 and level normalization element 15, the second 16 and third 17 OR elements.

The filter unit 2 is designed to filter the pilot frequency, which is a pair of pulse sequences, each pair containing a constant reference frequency and a reference frequency, the value of which varies from pair to pair (Fig. 2a). The filter block 2 is connected by a reference frequency output to the input of a reference frequency detection unit 3, and by outputs

control frequencies - to the corresponding inputs of the control frequency detection unit 7. The output of the signal frequency detection unit 7 is connected to the input of the unit

4 memory, which remembers the signal level of the reference frequency and maintains it until the parcel arrives at the reference frequency. The output of memory block 4 via channel switches 14 installed in n channels is connected to the corresponding inputs of the level normalization elements 15. The channel keys 14 are opened according to the signals coming from the corresponding; its output of the control frequency signal detecting unit 7. The number of keys and normalization blocks is equal to the number of control ones. frequencies. Each of the elements 15 of the normalization of the level in the n channels produces a quasi-reference normalized voltage level from the voltage of the reference frequency signal, with which the incoming voltage level of the control frequency signal is compared. All the first outputs of the leveling elements through the second element OR 16 are connected to the first input of the comparison unit 6, and all second outputs of the leveling elements through the third element OR 17 are connected to the second input of the comparison unit 6. The presence of two outputs of block 5 of the normalization level is due to two possible states, namely, k and op by an amount greater than

and and 1. and

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more than / 3 and add. The input of the display unit 10 is connected to the output of the key 9.

The device works as follows.

The input terminal 1 of the device receives a pair of sequence of pulses of the control signal (Fig. 2a). In each pair, one pulse is filled with the reference frequency f op, and the other - the control frequency f, - (where i 1, 2, 3, ...). The control signal is fed to the input of the filter unit 2, the output of which produces signals of different frequencies. The voltage of the reference frequency signal from the output of the filter bank 2 is fed to the input of the reference frequency detection unit 3, where the reference frequency signal envelope is formed (Fig. 26). This voltage enters memory block 4 and is remembered (Figure 2b). The voltage of the signal of the first control frequency opens the channel switch 14 of the first channel and transmits the voltage of the reference frequency signal from block 4 to the input of the voltage level normalization element 15 of the first channel. In element 15, depending on the voltage level of the reference frequency signal Ugn, a normalized voltage level is generated, against which the frequency response is controlled. Two cases of deviating frequency response are possible - from the norm: when UK 7 and and f. ifp and exceeds the permissible limit 4U onIf and | U (jp, the normalized voltage is taken from the first output of the element 15, which is equal to the part of the reference voltage U on (FIG. 2d). The value

This part of the voltage is determined by the permissible level of deviation from the frequency response at a given frequency. The normalized voltage is applied to the second input of block 6 of the comparison. On the other, the signal input of the comparison unit 6, the control signal frequency detection unit 7 and the first element OR 8 receive the full voltage of the signal and the control frequencies (FIG. 2e)

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If the magnitude of the change in its level is within, then block 6 of the comparison generates a Signal signal (Figure 2h). If the voltage of the signal U | control frequencies equal to or less than the normalized voltage and, i.e. changed by the magnitude greater than that, than that unit 6 of the comparison gives a signal Inefficient. This signal 20 is provided via key 9 to display unit 10. The operation of the device is controlled using coherent signals generated by three triggers. 25

The trigger driver 12 is triggered from the falling edge of the incoming voltage of the signal Up, the reference frequency, and determines the start time of the comparison of the voltages of the reference and reference control frequencies (Fig. 2e). The trigger voltage trigger 13 is triggered by the falling edge of the trigger torque trigger 12 and triggers a pulse, which determines the duration of the comparison process, and then opens the key 9 at this time (Figure 2g). switching voltage for 1Q A similar process occurs at each control frequency of the test signal in the nth channel.

Claims (1)

Invention Formula A device for monitoring the amplitude-frequency characteristics according to bus no. 1250987 is distinguished by the fact that, in order to increase the monitoring accuracy in the passband, the outputs of the control frequency detection signal detection unit are connected to the corresponding additional voltage level input block of the second and the third element OR of the level normalization channels, each of which contains a channel key and a level normalization element connected in series, the first output of each element of the norm The level is connected to the corresponding input of the second OR element, and the second output of each element of the leveling is connected to the corresponding input of the third OR element, the output of the second OR element is connected to the first output unit of the normalization voltage level, and the third edge is outputted from the back of the pulse from the 40th element. OR with the second exit trigger 13 and generates a pulse, which frees up memory block 4, preparing it to control the voltage level of the next pair of frequencies (Fig. 2i).  and on in block In the case when 6 comparisons compare the total voltage of the reference frequency, 15 20 25 2424 from the second output of element 15 and the voltage portion of the control frequency signal. In case part of the voltage  signal of control frequency is equal to or exceeds the full voltage of the reference frequency, a signal appears Inexpressible, which enters the display unit 10. 1Q A similar process occurs at each control frequency of the test signal in the nth channel. Invention Formula A device for monitoring the amplitude-frequency characteristics according to bus no. 1250987 is distinguished by the fact that, in order to increase the monitoring accuracy in the passband, the outputs of the control frequency detection signal detection unit are connected to the corresponding additional voltage level input block of the second and the third element OR of the level normalization channels, each of which contains a channel key and a level normalization element connected in series, the first output of each element of the norm The level is connected to the corresponding input of the second OR element, and the second output of each level normalization element is connected to the corresponding input of the third OR element, the output of the second OR element is connected to the first output unit of the normalization voltage level, the third output 45 e the voltage level regulation unit, the first input of each nth channel key is connected to each additional input of the voltage level regulation unit, the second input of each nth channel key is connected to the reference input of the voltage level regulation unit. / L Uon.  I I I I I I iJ TTT tL Uh -LF one ; i I l: :: fe.n I t uM TT. h t I I J-LI1I L I tt-m - fn   , J, jr- -HI -I - I - 4 : c (.. - | I I J-ll I n jr (.. - | j Fie.2