METHOD FOR DETERMINING EQUIVALENT NOISE TEMPERATURE OF AMPLIFIER INPUT Russian patent published in 1995 - IPC

FIELD: microwave measurement technology. SUBSTANCE: in order to determined noise temperature T₁, noise signal is supplied from standard noise sources having noise temperature T₂ and T_n to input of auxiliary amplifier whose noise temperature is similar to that of amplifier under test, and noise-signal power levels T₁ and T₂ are respectively measured at its output. Then noise signal is applied to input of amplifier under test from standard noise source having noise temperature P₁; noise-signal power level at the output is varied to value equal to measured value of P₂ at output of auxiliary amplifier, whereupon noise-signal power level is varied once more at its output to level equal to measured value of T₂; value M of this variation is measured and noise temperature P₂ of amplifier under test is determined using equation given in description of invention. EFFECT: improved measurement accuracy of high-gain (20-60 dB and higher) microwave amplifier noise temperature due to including linearity of their gain while applying noise signals having noise temperature P₁ and T_n to its input. 1 dwg