應用單極性電壓切換脈寬調變技術之高效率EER功率放大器之分析

Abstract

本文利用封包截平及回復法（EER）解決現代行動通訊對功率放大器線性度及效率之要求，特別針對封包放大器之有效頻寬及訊號延遲加以探討。本文提出單電壓極性切換脈寬調變技術應用於封包放大器之設計上，可同時解決由於元件切換速度不足所造成之頻寬不足及時間延遲過長的問題，進而提昇EER功率放大器之頻寬及線性度。並經由高頻模擬軟體ADS驗證EER系統應用於IS-95系統中之可行性。

Envelope elimination and restoration （EER）method is proposed to improve linearity and efficiency of power amplifier for modern digital mobile communication system. The limitations of bandwidth and signal delay in the EER amplifier are intensively examined. The technique of PWM (pulse width modulation) with unipolar voltage switching is presented to solve the problems of limited bandwidth and signal delay caused by low switching speed of the components simultaneously. In the meantime, the performance of the new EER amplifier applying to IS-95 system is studied by ADS.