SU1674386A1 - Transmit system channel characteristics scope - Google Patents

Abstract

This invention relates to a measurement technique. The purpose of the invention is to improve the accuracy and expansion of functionality. The device contains at the terminal station 1 control unit 2, display unit 3, measuring unit 4, amplifier 5, 6 discrete frequency generator, narrowband filter 7, band-pass filter 8, switching unit 9, program block 10, at intermediate stations 11 ₁ - 11 _M block 12 remote switching. Block 12 allows intermediate stations 11 to organize a loop or connection of appropriate frequency generators to measure the residual attenuation, amplitude-frequency characteristic, noise level and transient attenuation on the communication channels. The apparatus of clause 2 of the file is characterized by the implementation of block 12. 1 c. f-ly, 2 ill.

Description

The invention relates to a measurement technique and can be used to automatically, remotely measure and evaluate the state of communication channels and paths of transmission systems in communication networks of an arbitrary structure.

The purpose of the invention is to improve the accuracy and enhance the functionality.

FIG. Figure 1 shows a block diagram of a device for measuring the characteristics of transmission system channels; FIG. 2 is a block diagram of a remote switch unit.

The device for measuring the characteristics of the channels of the transmission system contains (Fig. 1) at the terminal station 1 control unit 2, display unit 3, measurement unit 4, amplifier 5, 6 discrete frequency generator, narrowband filter 7, band pass

filter 8, switching unit 9, software unit 10, at intermediate stations 111-11t, block 12 of the remote switch. Figure 1 also shows the measured communication channels 13. The remote switch unit 12 (FIG. 2) comprises a control command generation unit 14, a control frequency receiver unit 15, a frequency generator 16, a control frequency receivers 17, a switch 18 and a time relay 19.

The device works as follows.

In the memory of program block 10, the structure of the communication network, types of monitored channels, control parameters, characteristics of the equipment intended for operation over the listed channels, as well as possible

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causes of channel malfunctions with certain deviations of control parameters and possible ways of troubleshooting. The control signal from the software unit 10 is fed through the control unit 2 to the generator 6, which generates a control signal with the frequency fi - Line control, and the nominal level. In addition, the command generated by the control unit 2, the switching unit 9 provides connection of the generator output 6 to the direct direction of the measured communication channel 13. The control signal with frequency fi enters the measured channel 13 and is received by block 12 at the intermediate station 11. The presence of a signal of frequency f 1 in the reverse direction of the measured channel 13 at the intermediate station 11 is determined by the receiver 17 (Fig. 2). The response from the output of the receiver 17 includes a time relay 19, a logical signal 1 from time relay 19 and a receiver

17 enters the command generation unit 14. The command generation unit 14 generates control signals to the switch 18 and the generator 16. The switch

18 connects the control receiver receiver unit 15 to the reverse direction of the measured channel 13, through which the signal fi was received, as well as the output of the generator 16 to the forward direction of the measured channel 13. In addition, the generator 16 generates a confirmation signal at the frequency t2, which through The closed contacts of the switch 18 are supplied to the terminal station 1. The switching hold, which provides the input-output connection of the measured channel 13 of the communication of the elements of the block 12, is provided with a time relay signal 19 through the command generation unit 14. At the terminal station 1, the signal from the control unit 9 connects the input of the narrowband filter 7. tuned to the frequency f2 to the reverse measured channel 13 using the switching unit 9 through 5d. By a signal from control unit 2, amplifier 5 is put into the first amplifying mode. The response signal from the output of the reverse direction of the measured channel 13 is connected through switching unit 9, narrowband filament 7, amplifier 5 is fed to measuring unit 4, which is triggered by a control signal from the unit 2 controls By the level of the signal received at frequency f2. the residual attenuation of the measured channel 13 from the intermediate station 11 to the terminal station 1 is measured. The measurement result from the output of the measuring unit 4 through the control unit 2 enters the program unit 10 for storing and subsequent processing. If the level of the receipt signal at frequency h is greater than a certain threshold level that is set in program block 10, the display unit 3 sends a signal through the control unit 2 between the end station 1 and the intermediate station 11. The result of accurate level measurement of signal 0 is also output to block 3 la at frequency f2. After the termination of the sending of the signal fi from the terminal station 1 to the intermediate station 11 is automatically removed and. the signal at frequency h from intermediate station 11. After this, the command from program block 10, through control unit 2, disconnects narrowband filter 7 from the output of measured channel 13 and connects bandpass filter 8 with bandwidth,

0 equal to the bandwidth of the measured channel 13. Amplifier 5 is placed in the second gain mode, which is taken 30-40 dB more than the first gain mode. Gain mode one and two amplifiers are taken to

5 extending the dynamic range of unit 4, which contributes to reducing the error (improving the accuracy) of measurements. On command from control unit 2, unit 4 measures the noise level in measurement channel 13 from intermediate station 11 to terminal station 1. The difference in gain between the first and second gain modes of amplifier 5 is taken into account in software when processing the results. The result of the noise measurement is recorded in the memory of the software unit 10 and output to the display unit 3. The next command comes from software block 1C. through block 2

0 control oscillator b generates a signal at frequency i with a nominal level. This signal, through the switching unit 9, enters the control channel at the intermediate station 11. At the signal g which transmits

5, terminal station 1, a response signal with a frequency T2 from intermediate station 11 is not received. At the end station 1, the switching unit 9 reconnects the narrowband filter 7 tuned to the frequency f2

0, the amplifier 5 remains in the second gain mode, the measuring unit 4, at the command of the program unit 10, measures the value of the transition error at the near end through the control unit 2.

5 The measurement result is also entered into the program block 10 and displayed in the display unit 3 of the DSG.ee upon a command from the program unit 1C, the generator 6 generates a control signal at the frequency fs — a command loop through which the switch 9

arrives at the intermediate station 11. The presence of a signal with the frequency fa in the channel at the intermediate station 11 (FIG. 2) is determined by the receiver of the frequency fa from the block 15 of the receivers of the control frequency fa ... fN. The log 1 signal from the output of the receiver block 15 of the control frequency fa ... fN enters the command generation unit, which generates a command to the generator 16 to transmit the receipt of the terminal station 1 at the frequency f2 to the OS. After the end of the signal at frequency f3, the signal transmission at frequency f2 stops, the command generation unit 14 generates a control signal to the switch 18, which forms a loop (the forward and reverse circuits of the measured communication channel 13 are connected). In block 12 of the remote switching in the Loop mode, the block 15 of the control frequency receiver f ... remains to the control channel, and the generator 16 is turned off. A command from program block 10, through block 2 of control, the generator 6 sends a signal at frequency h with a fixed level to measured channel 13, which returns to the main structure of station 1. The measurement of the residual attenuation along the cable is carried out measuring the residual attenuation from the intermediate station 11 in the opposite direction of the measured communication channel 13 After the signal is removed at the frequency h, the noise level is measured at the loop fy as in the previous case. The amplitude-frequency characteristic (AFC) of the measured channel 13 is measured over the loop. In this case, the generator 6 generates frequencies in sequence by the command of the program block 10. .fnofi, which pass through the forward and reverse direction of the measured pump 13 and return to the main building of station 1. At the terminal station 1, at the command of the program unit 10, through the control unit 2, the switching unit 9 connects the band-pass filter 8. the amplifier 5 puts. In the first amplification mode, and the measuring unit 4 measures the frequency response. The result of the measurement is entered through the control unit 2 into the program unit 10. This completes the measurement cycle. The display unit 3 should then have the following channel characteristics: residual forward and reverse directions of the measured channel 13: transient attenuation at the near end: noise level; the resulting value of the frequency response of the forward and reverse directions of the measured communication channel 13. (The magnitude of the residual attenuation and noise is determined in program block 10). After the measurement cycle, the display unit 3 from the program unit 10 displays recommendations on the channel suitability for operation of certain types of equipment, and also in case of deviations of parameters from the established standards, the possible causes of the faulty display unit 3 are displayed. her and measures

to eliminate them.

Further, the commands of the software block 10 through the control block 2 of the generator 6 can generate a signal of one of the frequencies f.i., FN (switching in the direction 1 ... N). The reception signal at the intermediate station 111, for example, a signal at the frequency f-i, the presence of which is determined by the block 15 of control frequency receivers, in block 12 of the remote switching automatically

the loop is removed, the generator 16 generates a command confirmation signal at frequency f2, which enters the forward channel to the main structure of station 1 and indicates this. that the command of Commutation in direction 1 at the intermediate station is received. After the signal has been sent at the frequency f.i, the remote switching unit 12 carries out the transit switching of the communication line in direction 1. For example, to the intermediate station 112. Block 14, generator 16 and block 15 of control frequency receivers fa ffj from the transit direction in the block

12 remote switching off-with. fwioK 12 remote switching on

intermediate station 111 enters transit switching hold mode in direction 1. Switching is held by time relay signal 19.

Thus, a composite channel is formed from the terminal station 1 to the intermediate station 11t. At the intermediate station 112, a signal with a frequency fi (line monitoring) is sent over the composite channel, and so on. Principle

measuring the measured channel

13 is similar. The passage through the composite channel of the signal with the frequency fi starts the receiver 17 and again switches on the time relay 19, which holds the transit

switching on the switch 18 through the block

14forming teams. If the time interval during which the fi line control signal arrives, is longer than the start time of the time relay 19, in the remote switching unit 12, for example, in the intermediate station 1 11, the dialed direction is automatically dismounted to the intermediate station

112

After measuring the characteristics of the composite channel and using the known numerical values of the channel characteristics from the main structure of station 1 to intermediate station 11i, the characteristics of the communication channel between intermediate stations 111-112 are calculated. The measurement result is output to display unit 3. Next, the next link can be automatically and remotely connected to monitor.

Claims (2)

Claim 1. A device for measuring the characteristics of channels of transmission systems, comprising a display unit, a measuring unit, a discrete frequency generator and a serially connected software unit and a control unit at the terminal station, and a remote switch unit at each intermediate station, characterized in that To improve accuracy, a narrow-band filter and series-connected commutation, a band-pass filter and an amplifier are introduced at the end station; its output through the measuring unit is connected It is connected to the second input of the control unit, the first, second and third outputs of which are connected respectively to the control inputs of the amplifier, measuring unit and switching unit, the fourth output is connected to the first input of the program block, the fifth output is connected to the input of the display unit, and the sixth output through a disk generator is connected to the first input of the unit switching, the second output of which through a narrow-band filter is connected to the amplifier input, and information inputs and outputs of the switching unit through communication channels connected at intermediate stations to remote switch units. 2. The device according to claim 1, wherein the remote switch unit of each intermediate station includes a switch, a series of control receiver receivers, a control command generation unit and a frequency generator, the output of which is connected in series to the first control input of the switch and n circuits, each of which is designed as a series-connected receiver of control frequencies and a time relay, the outputs of which are connected to the corresponding second the inputs of the control command generation unit, the third input of which is connected to the combined second outputs of all control frequency receivers, n circuits whose inputs are combined with the corresponding information inputs of the commutator and are the inputs of the remote switch unit whose outputs are information outputs of the switch, vt the outputs of the command generation block Ј are connected to the corresponding second ynpaf. To the control inputs of the switch, the control output of which will be connected to the control input of the block, t control frequencies. : ,,. Tt  li L 1li I J No. I 1 .1L. J l1 LT) // j  / Fig 2