Modeling and Design Optimization of a Switched Capacitor RF Power Amplifier
Christos Adamopoulos, Panagiotis Zarkos
Abstract
The demand for spectral efficient modulation schemes and high data rates lead to non constant envelope RF modulated signals. This raises many challenges in the design of a linear and efficient Power Amplifier. This thesis attempts to examine different PA classes and linearization techniques. Firstly, several requirements for radio transmission are introduced in terms of Output Power (Pout), linearity and efficiency. In order to satisfy these requirements a linear and efficient PA is needed. To this end, different PA classes are analyses with a specific emphasis on Switching Mode PAs and class E. In order to address the challenge of the trade-off between efficiency and linearity of a PA several linearization techniques are presented. This serves as the background for the analysis and optimization of an architecture recently 6proposed, the Switched Capacitor Power Amplifier (SCPA). State space analysis of the amplifier is performed. Power derivation parameterized on component values and intermediated transformed impedances offers a tool for optimizing the SCPA for maximum output power and Power Added Efficiency (PAE). All theoretical results are verified via Cadence with a 65nm technology.