SU1566497A1 - Device for checking parameters of digit repeater of digit radio relay line - Google Patents

Abstract

The invention relates to radio and allows to increase the reliability of control. A device for monitoring the parameters of a repeater of a digital radio relay line 25 contains communication elements 1,2 and 9, controllable attenuators 3 and 4, switching units 5 and 6, a control unit 7, an error probability meter 8, a measurement receiver 10, filters 11 and 12 low frequencies, noise generator 13, adder 14, video generator 15, signal formers 16 and 17, generators 18 and 19, mixers 20 and 21, amplifiers 22 and 23, and generator 24 in a pseudo-random sequence. The purpose of the invention is achieved by taking into account the effect of crosstalk while reducing the monitoring time. At the same time, the maximum cross distortion corresponds to the maximum possible signal of the opposite direction of communication. In addition, the device according to claim 2 provides improved accuracy when monitoring repeaters with a common duplex path. 1 hp f-ly, 1 ill.

Description

The invention relates to a radio communication technique and can be used to control repeater parameters without regenerating a digital radio relay signal.

The purpose of the invention is to increase the reliability of control by taking into account the effect of cross-talk while reducing the time of control.

The drawing shows a structural electrical circuit of the proposed device.

A device for monitoring the parameters of a repeater of a digital radio relay line contains the first 1 and second 2

communication elements, first 3 and second 4 controlled attenuators, first 5 and second 6 switching units, control unit 7, error probability meter 8, third communication element 9, measuring receiver 10, first II and second 12 low-pass filters, noise generator 13, adder 14, video regenerator 15, first 16 and second 17 signal conditioners, first 18 and second 19 generators, first 20 and second 21 mixers, first 22 and second 23 amplifiers, 24 pseudo-random sequence generator (PSP) and controlled repeater 25 digital radio relay line.

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The device works as follows.

The first generator 18 sets the frequency) 1 d (or 1Г ff-i-fgM, which is insignificant), where f is the frequency of the output signal of the first driver 16 of the signal; fdec is the frequency of the input signal of the communication direction A. According to the signal from the control unit 7, the output of the connection of the third communication element, made as the third directional coupler 9, is connected to the input of the measuring receiver 10. The measuring receiver 10 is tuned to the frequency t. a signal generator 16 from the error probability meter 8, an NSP signal is supplied with a clock frequency corresponding to the clock frequency of a digital communication system in which a controlled repeater 25 is used. At the output of the first driver 16 of a signal, a signal is generated at frequency f, with modulation, which, by the form and parameters of modulation, constitutes the signals passing through the controlled repeater 25. At the output of the first mixer 20, a signal f is generated ad l Ј (, - Ј g, which after amplification, the first amplifier 21 pushes through the third directional coupler 20 and the first switching unit 5 to the measurement receiver 10. At the same time, the decay of the third directional coupler 20 is chosen so that the input signal is in the middle of the dynamic range of the input signals and The measurement receiver is 10 for the fact that its own myhbi were significantly lower. At the output of the measuring receiver 10, the detected PSP signal is allocated, which passes through the second low pass filter 12 to the first input of the adder 14, the pass band of the second low pass filter 12 is equivalent to the video passband of the video receiver to the input of the video recorder 15. The pass band of the measuring receiver 10 should be wider so that its frequency response of the frequency response and phase response does not distort the signal. In the adder 14, the output signal of the second low-pass filter 12 is summed with the signal of the noise generator 13 that passed through the first low pass filter 11, the frequency response of which is identical to the frequency response of the second low pass filter 12. At this level

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The noise signal is set in such a way that the signal-to-noise ratio at the input of the video regenerator 15 is equal to the nominal threshold value for the communication system, which includes the controlled repeater 25 (for example, 13 dB with a probability of Rosh 1 O - 3). ), An error probability measurement is taken from the error probability meter 8 if RT,

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This device is considered calibrated.

The device is calibrated in the same way according to the frequency of the input signal of the direction B

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Carrying out these calibrations allows one to evaluate the own parameters of the monitoring device, namely the parameters of its blocks, which form the input signals of the controlled repeater 25 and the parameters of the measuring receiver 10 of the device,

After calibration, the controlled repeater 25 is powered on, the output of the first amplifier 20 uses the first generator 18 to establish a signal with a frequency of fBx d, on a command from the control unit 7 through the first switching unit 5, the first controlled attenuator 3 and the first directional coupler 1 signal with frequency fgxA is fed to the input of communication direction A of controlled transponder 25, the output signal of controlled transponder 25 with frequency fB from the output of communication direction B through the communication output of the second directional from etvitel 2 and the second switching unit 6 is input to the measuring receiver 10 to levels similar to calibration. At the first controlled attenuator 3, the attenuation is set to correspond to the minimum sensitivity of the controlled transponder 25 (for example, 110 dBW), the noise generator 13 is turned off, the output signal of the measuring receiver 10 through the second low-pass filter 12, the adder 14 and the video recorder 15 are fed to the input The error probability meter 8, on which the error probability probability is calculated, if, the monitored repeater 25 is considered to be operational. By changing the attenuation value, you can determine

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energy reserve of the controlled transponder 25 or, vice versa, its deficiency. After that, the attenuation corresponding to the maximum signal at the input of the monitored repeater 25 (for example, 70 dB W) is set on the first controlled attenuator 3 (switch on the noise generator 13 (with the previously set d in the calibration process) and measure the probability error, if Paiu ROSH, the controlled repeater 25 is considered to be in good order. By changing the output level of the noise generator 13, it is possible to determine the margin of parameters of the controlled repeater 25

15

by the level of signal distortion or its deficiency (if P AT with respect to the signal-to-noise ratio is greater than the specified, for example, 15 dB). These measurements make it possible to estimate the integral characteristics of the monitored transponder 25, since at the minimum signal at the input, the threshold sensitivity of the monitored transponder 25 is measured with regard to its frequency characteristics. At the maximum signal at the input of the controlled repeater 25, the equivalent information confidence through the controlled repeater 25 is measured, brought to a threshold signal-to-noise ratio at the input of the video generator 15, which occurs in a real communication system taking into account amplitude and amplitude-phase characteristics. Then, in the same way, when the attenuation of the second controlled attenuator 4 is changed, the measurement of the direction parameters of the communication (input signal frequency f BKX) of the RI measurement of the monitored transponder 25 with the common duplex path is measured when measuring the parameters of the communication direction at the output of the second amplifier 23 the help of the second driver 17 of the signal to the input of which is fed a signal of the generator 24 PSP, similar to the PSI at the output of the meter 8 probability of error, and the second generator 19, the signal at the frequency fgx6 The signal is fed through the first switching unit 5 to another input-output of the controlled transponder 25. At the same time, the second attenuator 4 sets the minimum attenuation, since the maximum cross-section distortions correspond to the maximum possible

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a signal of the opposite direction of communication,

When measuring the direction, the measuring direction is loaded similarly.

Claims (2)

1. A device for monitoring the parameters of a digital radio relay line repeater, comprising an error probability meter, a control unit connected in series to a first switching unit, a controlled attenuator, and a first communication element whose output is the first input / output of the controlled digital radio relay repeater , the second switching unit connected in series to the second controlled attenuator and the second communication element, the output of which is the second input-output of the monitored repeater Digital radio relay line, characterized in that, in order to increase the reliability of monitoring by taking into account the effect of crosstalk while reducing the monitoring time, the first generator, series-connected noise generator and first low-pass filter, series-connected measuring receiver, whose information input is connected are introduced with the output of the second switching unit, the second low-pass filter, an adder, the second input of which is connected to the output of the first low-pass filter, and the video recorder op, the output of which is connected to the input of the error probability meter, the information output of which is the output of the device, the first shaper of CHI-nal connected in series, the input of which is connected to the output of the error probability meter; the first mixer, the second input of which is connected to the output of the first generator , the first amplifier is the third communication element, the output and the output of which are connected respectively to the first input of the first switching unit and the first input of the second switching unit, the second and third passes of which of outputs connected respectively to the communication of the first and second couplers, the second output of the first switching unit is connected to the inputs of a controllable attenuator. out, 1 block The controls are connected to the control inputs of the first and second switching units, the first, second and third communication elements being in the form of directional couplers. 2. The device according to claim 1, so that, in order to improve accuracy when monitoring retran-. additional duplex paths, a second generator, a pseudo-random sequence generator connected in series, a second signal conditioner, a second mixer, the second input of which is connected to the output of the second generator, and a second amplifier whose output is connected to the auxiliary input of the first switching unit, and the control inputs of the first and second generators, the first and second controlled attenuators, the measuring receiver and the noise generator are combined and are control th input device. i Editor 0. Head Compiled by E, Golub Techred M. Didyk Order 1229 Circulation 522 VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk nab. 4/5 Production and publishing plant Patent, Uzhgorod, st. Gagarin, 101 Proofreader S.Shevkun Subscription