SU1215060A1 - Apparatus for measuring amplitude and phase distortions of radio receiver signals - Google Patents

Abstract

The invention relates to a measurement technique and can be used to measure signal distortion occurring in radio receivers under the influence of interference. The purpose of the invention is to expand the functionality. The generator (G) 1 clock pulses is connected to the input G 2 of a pseudo-random sequence and one input of the phase detector (D) 12. The output G 2 is connected to the modulating input G 3 of the carrier frequency and the input of the Adjustable delay element 9. The output G 3 is connected to one input of the adder 4. G 5 noise through an attenuator 6 is connected to the second input of the adder 4. The output of the adder 4 is connected to the input of the radio receiver 7, the output connected to one input of the multiplier 8, the other input of which is connected to the output of the tunable delay element 9 . The output of the multiplier 8 is connected to the input of the amplitude D 11 and the input of the phase D 12. The output of the amplitude D 11 is connected to the first voltage meter 13. Phase D 12. is connected with a voltage meter 14. 1 hp f-ly, 1 ill.

Description

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The invention relates to a measurement technique and can be used to measure signal distortions that occur in radio receivers due to interference.

The purpose of the invention is to expand the functionality of the device due to the simultaneous measurement of the effective values of the amplitude and phase distortion of the signal in radio receivers

The drawing shows a block diagram of the device.

The device contains 1 clock pulse generator, 2 pseudo-random sequence generator, 2 carrier frequency generator 3, adder 4, noise generator 5, attenuator 6, radio receiver 7 under study, multiplier 8, tunable delay element 9, narrowband filter 10, amplitude detector 11, phase detector 12, the first voltage meter 13, the second voltage meter 14 and the first 15 and second 16 terminals of the device for connecting the radio receiver under study.

The clock pulse generator 1 is connected to the input of a pseudo-random sequence generator 2 and one input of the phase detector 12, the output of the pseudo-random sequence generator 2 is connected to the modulating input of the carrier frequency generator 3 and the input of the adjustable delay element 9, the output of the carrier frequency generator 3 is connected to one input of the adder 4, the noise generator 5 is connected via an attenuator 6 to the second input of the adder 4, the output of the adder 4 is connected to the input of the radio receiver 7, the output connected to one input of the multiplier 8, the second input of which is connected to the output of the tunable delay element 9, the output of the multiplier 8 is connected to the input of the narrowband filter 10, the output of which is connected to the input of the amplitude detector 11 and the second input of the phase detector 12, the output of the amplitude detector 11 is connected to the first voltage measuring device 13 The phase detector 12 is connected to a second voltage meter 14.

Clock generator 1 is a quartz oscillator

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torus assembled on a single chip 155 LAZ. The pseudorasynuclear sequence generator 2 is constructed on the basis of a 5-feedback shift register. A carrier frequency generator 3 is a high frequency sinusoidal voltage generator having a control input that is modulated.

0 pseudo-random sequence of carrier oscillation. The adder 4 is assembled on two broadband transformers. Noise generator 5 is a broadband noise generator with a uniform spectrum, covering all possible side channels of the radio receiving device under study. The controlled attenuator is assembled using p-i-n diodes, which provides uniform attenuation of interference over the entire frequency range of interference. The multiplier B is assembled on the chip 525 PS 2 in multiplication mode. The tunable delay element is a multi-tap delay switch switched. Narrowband filter 10 is tuned to a clock frequency and is a concentrated selection filter. The amplitude detector 11 is assembled according to a sequential amplitude detector using CD 509A diodes. The phase detector records the instantaneous phase difference at the clock frequency and is assembled on MA1 and 140 UD 5 microcircuits. Measuring device 13 is a DC voltmeter and measuring device 14 is an ac voltage meter, measuring the effective value of the input voltage.

The meter works as follows.

The pseudo-random sequence generator 2 operates at a clock frequency generated by the clock pulse generator 1, the output signal from the pseudo-random sequence generator 2 is fed to the modulating input of the carrier frequency generator 3 and performs amplitude, frequency or phase modulation of the high-frequency oscillation that is fed to one input of the adder 4 the second input of which through a controlled attenuator 6 is interfered with from the output of the generator 5

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noise. The sum of the signal and interference from the output of the adder 4 is fed to the input of the studied radio receiver 7, the output signal of which is fed to one input of the multiplier 8, to the second input of which through a tunable delay element 9, the delay of which is equal to the sum of the delay of the useful signal in the radio receiving path and half the clock time pulses, a signal is output from the generator 2 of a pseudo-random sequence, undistorted by interference. Narrowband filter 10 filters from the output signal of the multiplier 8 oscillation with a clock frequency f. A signal from the output of the narrowband filter 10, carrying information about the amplitude and phase distortions of the signal passing through the receiving path caused by interference, is fed to the amplitude and phase detectors. The effective value of the fluctuation component of the output voltage of the amplitude detector 11 is measured by measure 13, the output voltage of the phase detector 12 is the fluctuation voltage, the effective value of which is measured by the voltage gauge 14, and determines the average value of the phase fluctuations .

Claims (2)

1. An apparatus for measuring amplitude and phase distortion of signals of radio receivers, comprising 2150604 hence connected signal generator i, carrier frequency generator and an adder, the second input connected through a controlled attenuator to the output of the noise generator, the output of the adder is connected to the first terminal of the device for connecting the radio receiver under study, the second terminal of which is connected to the first input of the multiplier, whose second input connected through a reference radio receiver unit to the output of a carrier frequency generator, characterized in that, in order to expand the functional capability of the device, amplitude and phase detectors, two voltage meters and a narrowband filter are introduced into it, and the multiplier output through narrowband 20, the filter is connected to the inputs of the amplitude and phase detectors, the outputs of which are connected to the inputs of the corresponding voltage meters, the second input of the phase detector is connected to the second additional output of the signal generator, and the reference radio receiver unit is implemented as a delay element. 2. The device according to claim 1, wherein the signal generator is executed in the form of serially connected clock generator and signal generator in a pseudo-random sequence, the output of which is the first output, and the output of the clock generator - the second additional output of the signal generator .