SU1218474A1 - Device for measuring characteristics of transmission system channels - Google Patents

Abstract

This invention relates to a measurement technique. The purpose of the invention is to provide automatic remote measurements. The device contains at the terminal station (OS) 1 a control unit 2, a discrete frequency generator 3, a voltage-frequency converter 4, a measuring unit 5, a display and recording unit (BOR) 6, a program block 7, a remote control channel 8, and on each Intermediate station (LAN 9., - 9c - switch 10 and block) with voltage conversion - often 1 -fr: zJ: FPlWr t 4 (-) CZD1, f tfut.l that 11, two reverse communication channels 12, 14 and direct communication channel 13, the Device operates in three modes. In i self-test mode with equal input signals to measuring unit 5, software block 7 indicates readiness for measurements and sends a command to switch on BOR 6. In the automatic measurement mode of the frequency response of the transmission system, measurements of the frequency response of the forward and reverse channels are performed. connections 13 and 14 between OS1 and PS 9 -% at all normalized frequencies. In the automatic noise measurement mode of the transmission system, the noise of the forward and reverse communication channels 13. 14 is measured between the OS1 and all PS 9j -9ts, -a also measurements and Transition effect Nij between straight and inversely kanalami.ev connection 13 and 14, the program unit 7 generates a control yupsche command in accordance with a predetermined algorithm. A variant of the measurement unit 5 is given. 2 Il. (L With So 4 4

Description

The invention relates to a measurement technique and can be used to measure and control the electrical characteristics of channels and transmission system paths.

The purpose of the invention is to provide automatic remote measurements. I

Figure 1 shows the structural electrical circuit of the proposed device; figure 2 - diagram of the measuring unit.

The device for measuring the characteristics of the channels of the transmission system (fig. 1) contains at the end station 1 control 2, a generator of 3 discrete frequencies, a voltage-frequency converter 4, a measuring unit 5, a display and recording unit 6, a program block 7, a remote control channel 8, and at each intermediate station 9, -9, a switch 10 and a voltage-frequency conversion unit 11, an additional reverse link 12, as well as forward 13 and reverse 14 links.

The measuring unit 5 (Fig. 2) contains the first 15 and second 16 amplifiers, the first 17 and second 18 frequency-voltage converters, the frequency converter L9 and the low-pass filter 20.

The device works as follows.

In the self-test mode at the terminal station 1, the software unit (Fig. 1) issues preparatory commands to the control unit 2 and the generator 3. The control unit 2 sends a control signal through the remote control channel 8 to the switch 10 of the corresponding intermediate station 9 | to create a validation scheme. The voltage of the test signal from the generator 3 output goes through the forward link 13 and the switch 10 of the first intermediate station 9 to block 11, where it is converted into a frequency corresponding to the level value, which through the additional return link 12 goes to the measuring unit 5. At the same time, the test signal of the nominal level from the generator 3 is supplied for comparison through the converter 4 to the measuring unit 5, from where

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The measurement result is output to the display and recording unit 6, and the comparison result is transmitted to the software block 7, 5 to signal the need to increase the level of the signal supplied to the forward link 13, and delay the command to activate the display and register 6 - 10 walkie-talkies. On the received signal, the program-1 frame unit 7 generates a command to increase the level of the generator 3, which is fed to the forward link channel I3 by decreasing

15 of the attenuation value of the extension cable at the output of the generator 3. When the input signals to the measuring block 5 are equal, the program block 7 signals the readiness of 20 to measure and prompts the command to

the inclusion in the work of block 6 of the display and registration.

In the mode of automatic measurement of the amplitude-frequency characteristic (AFC) of the transmission system, the software unit 7 issues successively commands to control unit 2 and generator 3. Control unit 2 sends control signals through. the telecontrol channel 8 to the switch 10 is the first 9, and the second 9 intermediate stations to disable the test circuit and create a measurement circuit. Measuring voltage

the signal from the output of generator 3 goes through the direct communication channel 13, the switch IO of the second intermediate station 9, to the conversion unit 11 of this station, where it is converted

to the frequency corresponding to the level value, which through the additional return channel I2 of the communication enters the measuring unit 5, from where the measurement result is output

The display and recording unit 6, and the result of the comparison with the measurement signal from the generator 3 through the converter 4, is supplied to the program unit 7. When

disabling the comparison result from the normal program block 7 delays the rest of the commands and delivers a fault signal. When the comparison signal is found in the normal state, the software unit 7 issues commands to the control unit 2, which sends control signals via the remote control channel 8 to the commutator frequency generator j connected at the terminal station. The program block and the control unit, the measuring unit, the first output of which is connected to the input of the program block, the second output of which is connected to the input of the discrete frequency generator; the first output of which is the input of the forward link channel, the first input of the measuring unit Loka is the output of the reverse link, and at each intermediate station, serially connected commune-Gore and voltage conversion unit — frequency, the first. and the second information inputs and outputs of the switch are the outputs and inputs of the forward and reverse communication channels, respectively, characterized in that, in order to provide automatic remote compilers E.Golub Editor N.Shvydka Tekhred Corrector E.Sirokhman

Order 1139/61. Circulation 624 Subscription VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Branch ITS Patent, Uzhgorod, st. Project, 4

In the end station, a voltage-frequency converter and a display and recording unit are entered into it, - the first and second inputs of which are connected respectively to the second output of the measuring unit and the third output of the program block,

the second output of the discrete frequency generator is connected to the input of the voltage-frequency converter, the output of which is connected to the second input of the measuring unit, the output

the control unit is connected via the entered remote control channel to the control inputs of the switches of all intermediate stations, and the yards of the voltage-frequency conversion blocks of all intermediate stations are connected through the input additional reverse link; to the first input of the measuring unit.

the tori 10 are second 9 and third 9, intermediate stations to create a measurement circuit. The process of measuring the AHC forward link channel 13 between the terminal 1 and intermediate 9 stations is carried out similarly.

Thus, the measurement of the AHC forward 13 and the reverse 14 communication channels between the terminal station 1 and the intermediate stations 9f, and at all normalized frequencies is carried out. According to the display and registration unit 6, it can be concluded that it is necessary to adjust each section of the transmission system.

When measuring the reverse link 14 in the switch 10 of the corresponding intermediate station 9, a signal from the control unit 2 forms a loop from transmission to reception via an extension cable corresponding to the difference in the normalized levels at the output of the forward 13 and the reverse link input 14.

In the automatic noise measurement mode of forward 13 and reverse 14 communication channels of the transmission system, the software unit 7 sends commands to the control unit 2, which sends control signals through the remote control channel 8 to the switches 10 of the first and second intermediate stations 9, - 9 ,. By these signals, the input of the forward link channel 13 at the first intermediate station 9 is loaded with a matched resistance, and its output at the second intermediate station 9 is fed to the conversion unit 1I. The noise voltage, converted to a frequency, via an additional return channel 12 is fed to the measuring unit 5, from where the measurement result is output to the display and recording unit 6.

The process of measuring the noise of the forward link channel 13 between the terminal 1 and the second intermediate 9 stations is similar. In the same way, the measurement of the noise of the forward 13 and reverse 14 communication channels between the terminal station 1 and all intermediate stations 9 - is carried out. 9. When measuring the reverse channel I4 connection, its input in the switch 10 is 18474

According to the signal from control unit 2, the corresponding intermediate station 9 is loaded for a consistent resistance. According to the 5 measurements recorded by the display and recording unit 6, it can be concluded that it is necessary to adjust each section of the transmission system.

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Transient measurement process

the effects between the forward 13 and the reverse 14 of the communication channels are made similarly to the measurement of the noise of the reverse communication channel 14, while on the forward communication channel 13 loaded on the signal from the control unit 2 to the matched resistance, an influencing lsignal from generator-: torus 3 by software command

ts

20

block 7.

Signal frequency 4 additional30

A return communication channel 12 is fed through the first amplifier 15, which compensates for its attenuation, to the first frequency-voltage converter 17 (Fig. 2). As a result of the conversion, a voltage level of the measured signal is generated, which is fed to the display and recording unit 6.

A part of the signal from the first amplifier 15 of the same frequency t is fed to the input of the frequency converter 19. The input of which is fed to another input

35 reference signal with frequency f from converter 4. Frequency difference (1d-1) from the output of frequency converter 19 is fed through a low-pass filter 20 and a second amplifier

0 16 to the second frequency converter 18 voltage. A low pass filter 20 is needed to filter out other combinational components at the output of the converter 19.

45, and the second, amplifier 16, to provide a normal signal at the input of the second frequency-voltage converter 18. The signal from the output of the second transducer 50 tel 18 frequency voltage is fed to the software block 7 for generating control commands in accordance with a predetermined operation algorithm

Claims (1)

55 Formula and Consensus A device for measuring channel characteristics of transmission systems.