SU1506562A1 - Device for measuring signal-to-noise ratio in radio receiver - Google Patents

Abstract

This invention relates to a measurement technique. The purpose of the invention is to improve the measurement accuracy. The device contains a synchronous detector 1, a voltage driver 2, a delay element 3, a signal regenerator 4, a multiplier 5, a peak detector 6, a band-pass filter 7, a quadratic detector 8, low-pass filters 9 and 10, and a recording unit 11. An additive mixture of the video signal and noise is fed to the regenerator 4, where the optimal processing of each of the elementary premises of the video signal occurs and a decision is made about its sign. Further, the multiplier 5 eliminates the sign uncertainty of the video signal by performing the multiply operation of the analogue signal, after which the detector 6 samples and memorizes the level of this signal. The output of detector 6 contains a constant voltage proportional to the input signal level, and a noise component, which is separated by filter 7 and fed to detector 8. From detectors 6 and 8 through filters 9 and 10 constant voltages proportional to the level of the signal and noise arrive at the signal-to-noise ratio registration unit 11 in the radio receiver. The goal is achieved by introducing detector 6 and filters 7.9 and 10. 1 sludge.

Description

The invention relates to a measurement technique and is intended to measure the signal-to-noise ratio in coherent radio receivers with phase manipulation techniques.

The purpose of the invention is to improve the measurement accuracy.

The drawing shows the electrical circuit diagram of a device for measuring the signal-to-noise ratio in a radio receiver.

The device contains a synchronous detector 1, a voltage driver 2, a delay element 3, a signal regenerator 4, a multiplier 5, a peak detector 6, a band-pass filter 7, a quadratic detector 8, low-pass filters 9 and 10, and a recording unit 11.

The device works as follows.

The MoMf HThi time corresponding to the maximum of the sitnal-noise ratio samples and memorizes the level of the signal coming from multiplier 5. At the output of peak detector 6 there is a constant voltage proportional to the level of the input signal and the noise component. Through the band-pass filter 7, the noise component is separated from the constant component and fed to the input of the quadratic detector 8. Through the filters 9 and 10 connected to the outputs of the peak detector 6 and the quadratic detector 8, respectively, the constant voltages proportional to the level of the signal and noise, arrive at the inputs of the signal-to-noise ratio registration unit 11.

Claims (1)

Invention Formula 35 An additive mixture of the signal, manipulated in phase, and noise arrives at the first input of the synchronous detector 1 and the input of the reference voltage generator 2, the output of which forms the reference voltage coherent to the carrier frequency of the input signal. The reference voltage is fed to the second input of the synchronous detector 1. From the output of the synchronous detector 1, an additive mixture of video signal and noise is fed to the input of the regenerator 4, where during the TO time equal to the duration of the video signal elementary, each of the video signal feeds is received and received Q tie decisions about her sign. The multiplier 5, which serves to eliminate the sign uncertainty of the video signal, performs the sign-analog multiplication operation. Since the information about the sign of the parcel at the first input of the multiplier 5 appears after time T, the analog video signal arriving at its second input is also delayed by time T via an electronic unit for measuring the signal-to-noise ratio in a radio receiver containing a quadratic detector, display unit , a signal regenerator and a serially connected reference voltage driver, a synchronous detector, a delay element and a multiplier, and the output of the synchronous detector is connected to the generator via a signal generator The other input of the front panel, the input of the voltage driver, is combined with the second input of the synchronous detector and is the first input of the device, which is characterized by the fact that, in order to improve the measurement accuracy, the first and second low-pass filters are introduced and sequentially connected peak a detector and a band-pass filter, the output of which is connected to the first input of the recording unit through the series-connected quadratic detector and the first low-pass filter, the second input of which is connected via the second low-pass filter dinene with the output of the peak detector, the first input of which is connected to 45 n 1 pa x J, “i jji f y, j.Ttrt, fi. cop 3 delays. The peak detector is 6, multiplied by the output, and the second input is controlled by clock pulses, Compiled by V.Kamal gin Tehred M. Khodanych Editor S.Patrusheva is the second input of the device. Proofreader T.Malets A device for measuring the signal-to-noise ratio in a radio receiver, comprising a quadratic detector, a display unit, a signal regenerator and a serially connected reference voltage generator, a synchronous detector, a delay element and a multiplier, and the output of the synchronous detector is connected to another input - the multiplier, the input of the reference voltage driver is combined with the second input of the synchronous detector and is the first input of the device, which is characterized in that, in order to improve the accuracy the first and second low-pass filters and the successively connected peak detector and band-pass filter, the output of which is connected to the first input of the recording unit through the successively connected quadratic detector and the first low-pass filter, the second input of which is connected to the second input through the second low-pass filter output peak detector, the first input of which is connected to f y, j.Ttrt, fi. output multiply I, and the second input output multiply, and the second inlet Kamal gin ich is the second input of the device. Proofreader T.Malets