Frequency conversion of flicker noise in bipolar junction transistors

A novel experimental system for the investigation of frequency-translated flicker noise in bipolar junction transistors is demonstrated. First, transistors are characterized for their base-emitter junction behavior and flicker noise parameters in steady state. Then the conversion gain of the baseband flicker noise to the sidebands of the carrier is measured for several different carrier levels upon the application of a large-signal carrier to the transistors under test. The measured conversion gain is compared to that predicted using a harmonic balance noise simulation. Discrepancies between measurement and simulation indicate the presence of an effect not currently addressed in the literature.