SU1231616A1 - Method of measuring amplitude-frequency response of communication channel - Google Patents

Abstract

The invention relates to telecommunications. The purpose of the invention is to simplify the measurement by eliminating the selection of measurement signals (ICs) in frequency. In accordance with a predetermined program, the frequency of the IC varies alternately from G | DOP, and the signal level of each frequency increases in steps from the minimum to maximum values, i.e. in the range of + others from the nominal value. In addition, the JC at each level level is transmitted as a short-term filling of the pulse frequency with smooth edges in order to eliminate interference when the IC is turned on and off. The goal is achieved due to the fact that the transmission level of the IC is set above the power level of the communication path load signals. 1 il. § w 55 55

Description

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The invention relates to telecommunications and can be used to conduct automated measurements of the amplitude-frequency characteristic (AFC) of group and linear paths of transmission systems over cable, radio relay and other communication lines.

The purpose of the invention is to simplify the measurement by eliminating the selection of measurement signals in frequency.

The drawing shows a structural electrical circuit of the device implementing a method for measuring the amplitude-frequency characteristic of the communication path.

The device contains a unit 1 for controlling and recording measurement data, a generator 2, resistors 3 isolations, a measuring path.4, a detector 5, a comparator 6, a transmitter 7 of the acknowledgment signal, a reverse path 8 of communication, the receiver 9 of the acknowledgment signal, amplifiers ten.

The method of measuring the frequency response of the communication path is as follows. The transmission level of the measurement signals is set higher than the power level of the communication path loading signals.

The generator 2 operates according to the program signals 30 generated by the unit 1 for controlling and recording measurement data. In accordance with this program, the frequency of the measurement signals is alternately changed ot, dP, and the signal level of each of the frequencies increases in steps from the minimum to the maximum, i.e. in the range of + nominal value. In addition, the measurement signal at each level 40 step is transmitted as a short-term filling of the pulse frequency with smooth edges in order to eliminate interference when the measurement signals are turned on and off.

Thus, measurements begin with the introduction of a frequency F signal into the measurement path, with a minimum transmission level. If, for example, there is no frequency response at this frequency, then when the measurement signal is applied with a minimum level (at the reception this signal is detected and fed to the comparator), the comparator 6 receives

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the station does not work because its communication path is 55, the level can not be measured only if the coherent signal at each frequency and the level of the measuring signal equal periodically change the sequence or exceed the nominal value from minimum to maximum.

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reading This means that the transmitter 7 acknowledging signal, etc. does not work either.

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Due to this, the process of increasing the levels will continue in this case to the value of the nominal level, when reached, the comparator 6 and transmitter 7 of the acknowledgment signal of the receiving station are triggered and, therefore, the receiver 9 of the acknowledgment signal at the transmitting station. The signal of the latter enters the unit 1 to compare and record measurement data, thereby blocking the switching process of the generator level 2 and discharging the ne4atb measurement data, including the data on the frequency and level of the measuring signal corresponding to the matching of the comparator 6 at the receiving station. The deviation of this level from the nominal value is equal in absolute value to the deviation of the frequency response at the receiving station. The frequency response measurements are as follows. Alternately on. Often ..-- max from F, TO P "by increasing the level

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steps at each frequency until a comparator is triggered at the receiving station, after which the measurement data is recorded and the next frequency of the measuring signal is turned on, etc.

Claims (1)

5 claims A method for measuring the amplitude-frequency characteristic of a communication path based on introducing into the communication path on the transmitting side a sequence of measurement signals whose frequencies are located in the inter-channel spans of the communication path, detecting measuring signals on the receiving side and comparing the levels of the detected signals reference voltage, characterized by the fact that, in order to simplify the measurement by eliminating the selection of measurement signals by frequency, on the transmitting side the transmission level is measured Yelnia signal level is set between the average path load signal and power communication level pere0 in the range of permissible deviations from the nominal value at a given frequency, and at the receiving side, when the level of the detected signal of the reference voltage exceeds the detected level Editor A.Revin Compiled by A.Seselkin Tehred O.Gortvay Proofreader L.Pilipenko 2662/58 Circulation 624 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab. A / 5 Production and printing company, Uzhgorod, st. Project, 4 transmission null, the acknowledgment signal is transmitted back to the communication path, followed by fixing on the transmitting side the level of the measurement signal and the level deviation from the nominal value at a given frequency. ffpucMHO station