Efficiency Improvement of Power Amplifier Using a Digitally-Controlled Dynamic Bias Switching for LTE Base Station

Abstract This paper presents an efficiency enhancement for the high power amplifier using DDBS(Digitally-controlled Dynamic Bias Switching) method which dynamically provides the power amplifier with two bias voltage levels according to the input envelope signal. It is quite easy to adjust the control signal by using a digital processing. The fabricated DDBS PA was evaluated using an 64 QAM FDD LTE signal, which has a center frequency of 2.6 GHz, a bandwidth of 10 MHz and a PAPR of 9.5 dB. The DDBS increases the power amplifier’s PAE(Power-Added Efficiency) from 40.9 % to 48 %, at an average output power level of 43 dBm. Key words: Digitally-Controlled Dynamic Bias Switching, Envelope Tracking, High Power Amplifier  IJK1LM N(CN JOJKAP(QRS3 /XY"1ZClass-S .JK.[ \]>^_C`Y"a^N(School of Information and Communication Engineering, Sungkyunkwan University) *DZbY"JKc(Electronics and Telecommunications Research Institute)Manuscript received June 26, 2014 ; Revised July 29, 2014 ; Accepted August 6, 2014. (ID No. 20140626-01S)Corresponding Author: Youngoo Yang (e-mail: yang09@.skku.edu)