Amplification in Linear Mode
Jean‐Luc Gautier, Sébastien Quintanel · 2014
This chapter discusses the essential characteristic values of an amplifier namely, power gain, input and output impedances, frequency band of operation and noise factor. The linearity of the amplifier is characterized by maximum input or output power to ensure linear operation of the amplifier. The chapter provides a review of active two-port networks in linear mode. The performance of an active two-port network in linear mode, consisting of a transistor and passive components, is based on transistor characteristics, DC polarization point and value of impedances presented at ports 1 and 2. The chapter talks about narrowband amplifiers with maximum gain and uses the characteristics of a PHEMT transistor as an example. It also discusses characteristics of other commongrid (common-base) and common-drain (common-collector) conventional configurations, and presents the performances of the component that are equivalent to a two-transistor cascade. Finally, the chapter presents a discussion on differential amplifiers.