SSPA Linearization

摘要

Many new communications services require highly linear high power amplifiers (HPA). This article is an extension of an earlier article that discussed the merits of linearization and its application to traveling-wave tube amplifiers. Here, the emphasis is on solid-state power amplifiers (SSPA). Common SSPA linearization methods are compared and found to offer significant benefit when used with both bipolar and Si/GaAs FET power amplifiers. Problems unique to SSPAs, such as bias-induced, time-dependent nonlinearities, are highlighted. Predistortion is demonstrated to be the preferred linearization approach for many applications.