24.4 A Watt-Level Multimode Multi-Efficiency-Peak Digital Polar Power Amplifier with Linear Single-Supply Class-G Technique

摘要

Signals for next-generation communication systems typically have high peak-to-average power ratios (PAPR) (e.g., 10 to 13dB), forcing operation at deep output power backoff (PBO). A good efficiency at PBO is required to maintain high average efficiency. Typical power amplifiers (PAs) demonstrate degraded efficiency at high PBO levels, which causes a significant degradation in efficiency, particularly for signals with high PAPR. Efficiency-enhancement techniques using digital PAs (DPAs) have been extensively introduced (e.g., Class-G, Doherty, etc.). DPAs have been shown to be great choices for efficiency enhancement at PBO, because each DPA cell can change the operating mode while switched OFF during the mode transitions, resulting in better linearity and seamless efficiency enhancement at PBO.