1/f AM and PM noise in a common source heterojunction field effect transistor amplifier

Microwave amplifier design employs the concept of a two-port network. Two-port networks can be examined by their characterizing parameters. At alternating current frequencies of operation of 300 [MHz]-300 [GHz], it is useful to characterize a two-port network by scattering parameters which provide the signal transmission and reflection power ratios, and signal power gain of a two-port network. Heterojunction field effect transistor (HFET) architecture provides high carrier mobility. For this reason, HFETs are often used in microwave amplifiers. In this work, I characterize the scattering parameters of a GaAs HFET amplifier. The large signal model for analysis of the HFET we have chosen is Triquint's Own Model (TOM1). The correspondence of the scattering parameter measurements of the HFET model with both the manufacturer specifications and the measured scattering parameters provides validation before amplifier design. Scattering parameter measurements were taken on the constructed amplifier to include the effects of the signal transmission media and bias components. The characterization of the scattering parameters of a common-source configuration of a HFET amplifier was then achieved. From the characterization, a computer model was developed and used to examine amplitude and phase modulated noise properties in the amplifier. These properties include the signal amplitude and phase noise sensitivity to the low frequency drain current noise of the amplifier.