SRK 2024

POVZETEK
Sodobni sprejemni sistemi morajo pogosto obdelovati zelo šibke signale, vendar šum, ki ga dodajajo komponente sistema, ponavadi zakrije te zelo šibke signale. Občutljivost, razmerje bitnih napak (BER) in šumno število so sistemski parametri, ki označujejo sposobnost obdelave signalov nizkega nivoja. Med temi parametri je šumno število tisto, ki omogoča ne samo karakterizacijo celotnega sistema, ampak tudi posamičnih komponent sistema, kot so predojačevalniki, mešalniki in medfrekvenčni ojačevalniki. Potreba po zelo ponovljivih, natančnih in smiselnih meritvah šuma brez zapletenih ročnih meritev in izračunov je privedla do razvoja instrumentov za merjenje šumnega števila s preprostimi uporabniškimi vmesniki. Obravnavane bodo metode merjenje šumnega števila, ki jih uporabljajo instrumenti.

ABSTRACT
Modern receiving systems must often process very weak signals, but the noise added by the system components tends to obscure those very weak signals. Sensitivity, bit error ratio (BER) and noise figure are system parameters that characterize the ability to process low-level signals. Of these parameters, noise figure is unique in that it is suitable not only for characterizing the entire system but also the system components such as the pre-amplifier, mixer, and IF amplifier that make up the system. The need for highly repeatable, accurate and meaningful measurements of noise without the complexity of manual measurements and calculations has lead to the development of noise figure measurement instruments with simple user interfaces. Methods for noise figure measurements used in a such instruments will be discussed.