Comparison of Efficiency Enhancement Techniques for RF PAs

With increasing data-rates, the RF signal’s peak-to-average power ratios (PAPR) are continually growing. RF power amplifiers must process these high PAPR signals while maintaining reasonable efficiency. A variety of efficiency-enhancement techniques exist to: 1) improve peak PA efficiency and 2) improve efficiency of PAs under backoff power conditions for high-PAPR communications signals. This tutorial talk will give an overview of these various efficiency enhancement techniques and summarize their fundamental theories of operation. The various techniques, such as envelope tracking, load modulation, adaptive biasing, etc, shall be compared against one another with respect to design/implementation challenges and best use-case applications.