The measurement technique and investigations results of amplitude and phase stability of super heterodyne radio astronomy receiver
Keywords: радиоастрономический приемник, многокаскадный приемник, дисперсия Аллана, стабильность коэффициента усиления, фазовая стабильность, флуктуацииAbout the paper
The measurement technique and investigations results of amplitude and phase stability of multistage super heterodyne radio astronomy receiver are presented. Investigations are performed in three (S, X, Ka) bands of the radio telescope RT-13 receiving system of the «Quasar» VLBI network. The main sources of fluctuations and their types on different time scales are identified using Allan variance calculations. The contribution of separate stages fluctuations to the overall receiver stability is determined, taking into account the correlations between stages fluctuations. The influence of transistor voltage fluctuations on cryogenic amplifier gain fluctuations is investigated also. Phase stability of the receiver frequency conversion stage is measured using 3 ports of vector network analyzer.