SU786017A1 - Device for simultaneous measuring of pulse noise and level pauses in communication channels - Google Patents

Description

clock pulses, the output of which is connected to the combined second inputs of the first and second elements I, the time relay whose output is connected to the combined installation inputs of the first and second counters, and the series-connected decoder and indicator, an envelope filter, an additional decoder and an additional indicator are inserted, the output of the first amplitude selector is connected to the first input of the first element I, the output of the first counter is connected to the input of the decoder, the output of the matching unit is through The second full-wave rectifier and the envelope filter are connected to the input of the second amplitude selector, and the output of the second counter is connected to the input of the additional indicator via a serial decoder.

FIG. Figure 1 shows the structural electrical circuit of the proposed device. FIG. 2 - timing diagrams for the operation of the device.

The device contains a control signal generator 1, a level 2 regulator, a communication channel 3, a matching unit 4, an amplifier 5, a level interruption measurement path 6, which consists of a first full-wave rectifier 7, a low-pass filter 8, the first amplitude selector 9, the first element 10, the first counter 11, the decoder 12, the indicator 13, the pulsed interference measurement path 14, which consists of the second full-wave rectifier 15, the envelope filter 16, the second amplitude selector 17, the second element 18, the second counter 19, ADDITIONAL decoder 20, an additional indicator 12, a clock generator 22 and a time relay 23.

The device works as follows.

The generator 1 generates a control frequency signal equal to approximately the average frequency of the signal with a level equal to the nominal signal level at the connection point of the communication channel 3, against which the interruptions are measured. Regulator 2 underestimates the level of the signal fed to channel 3 by 12 dB, which makes it possible to select the optimal, from the point of view of error, measurement mode. At the output of channel 3, the signal is the sum of the voltage of the control frequency modulated by interruptions and the voltage of the pulsed noise (see FIG. 2a). From the output of channel 3, the signal arrives at block 4, which reconciles channel E with the input of measuring devices

The separation of the signal into two measuring paths - path 6 and path 14 is carried out with the help of amplifier 5, which increases the transmission coefficient of path 6 by 12 dB (see Fig. 26), which compensates for the attenuation introduced at the transmission. The signals at the inputs of the measuring paths 6 (see Fig. 2, b) and 14 (see Fig. 2, a) with respect to the set analysis thresholds are identical to the signals with divided measurements. Further processing of the measurement results (see Fig. 2, in ID) and their indication are performed in a manner similar to known devices.

The proposed device makes it possible to measure both interferences and interruptions with practically permissible equal error due to the fact that the measurement error of interferences decreases as the signal level in the channel decreases.

Due to the simultaneous measurement of noise and interruptions with increased accuracy in comparison with known devices, the measurement time is significantly reduced, which increases the productivity of the measurement.

In addition, the proposed device is simplified. It lacks complex notch filters.

Claims (1)

1. Data transfer channels. Ed. V, O. Shvartsman.M., Svyi / 1970, p. 276-278 (prototype).