SU928256A1 - Device for measuring noise factor - Google Patents

Description

(5 DEVICE FOR MEASURING THE COEFFICIENT

NOISE

one

The invention relates to a measurement technique and can be used in panoramic measuring the noise figure (CS) of two-port networks.

A device for measuring KS is known, comprising a periodic signal generator, a bandpass amplifier, a threshold element, an integrator, a relay and counters of the number and duration of pulses. The device is calibrated with a known signal. Thereafter, the quadrupole is connected to a bandpass amplifier, the bandwidth of which determines the frequency band in which the CS is measured. The threshold element extracts noise signal pulses above the reference level, which are then integrated and fed to the control input of the relay. About the value of KSH judge t according to the readings of counters 1.

The disadvantage of this device is the limited range of measured frequencies.

The closest technical solution to the invention is a KSH device containing a noise source which, through a quadrupole under study, is connected to a low-power meter whose output via a non-electronic key. mediocre connected to the digital logarithmic voltage measurement, which through the adder

to is connected to a calibration number input unit. The output of the adder is connected to a digital indicator U.

However, this device does not allow panoramic measurement of the CS in the frequency range in a given time interval.

The purpose of the invention is to reduce the measurement time in the frequency range.

Claims (2)

The goal is achieved by the device for measuring the noise factor containing a noise source, the first output connected to the first input terminal of the device, and the second output to the first input of an electronic key, the second input of which is connected to the output of a low power meter Whose voltage ratio meter whose second input is connected to the output of an electronic key, and the output of the digital logarithmic voltage ratio meter is connected to one of the inputs of the adder, the second input The output of the calibration numbers input unit is costly, and the output of the adder is connected to the indicator input, a frequency converter and a oscillating frequency generator are entered, the first input of the frequency converter is connected to the second input terminal of the device, and its output is connected to the Meter meter, and the second input the frequency converter is connected to the first output of the oscillating frequency generator, the second output of which is connected to the control inputs of the calibration number input unit and the indicator performed by the oscilloscope afimeskym The drawing shows the block diagram of the device. The device contains a source of 1 noise j used quadrupole 2,, low power meter 3, electronic key k, digital logarithmic meter 5 ratio of voltage adder 6, blink 7 input of calibration numbers, oscillographic indicator B, frequency converter 9, oscillator 10 oscillating frequency input terminals 11 and 12 devices. The device works as follows. The noise signal from the noise source 1 passes the quadrupole 2 under study and, together with its noise, enters the input of the frequency converter 9. The latter transmits a frequency band, the central frequency of which is tuned using the output signal of the sweep frequency generator 11. The control voltage from the digital output of the oscillating frequency generator goes to the calibration number input unit 7, where it automatically, depending on the center frequency, controls the calibration numbers and to the digital oscillographic indicator 8, where it sweeps the beam. The signal input of the digital oscilloscope of the raphic indicator 8 receives information about the value of the noise figure in a digital form. . If the studied quadrupole contains its own frequency converter, then it is switched on instead of frequency converter 9. The technical means introduced allow panoramic measurement of the noise figure in the frequency range under study. The measurement time of the CS in the frequency range is reduced by 8.5 times. The invention The device for measuring the noise figure, containing a noise source, the first output connected to the first input terminal of the device, and the second output to the first input of an electronic key, the second input of which is connected to the output of a low power meter and the first input of a digital logar ratio meter , the second input of which is connected to the output of the electronic key, and the output of the digital logarithmic voltage ratio meter is connected to one of the inputs of the adder, the second input is cat connected to the output of the input block of calibration numbers, and the output of the adder is connected to the input of the indicator, so that, in order to reduce the measurement time in the frequency range, a frequency converter and a oscillating frequency generator are introduced into it, In this case, the first input of the frequency converter is connected to the second input terminal of the device, and its output is connected to the low power meter, and the second input of the frequency converter is connected to the first output of the oscillating frequency generator, the second output of which is connected. yuschimi inputs an input unit and an indicator gauge numbers performed oscillographic. Sources of information taken into account in the examination 1. USSR author's certificate number 299809, class, G 01 R 29/00, 19b9. 2. USSR author's certificate №, cl. G 01 R 23/00, 1973 (prototype). 1G -I j L.I. ten t45