Techniques of envelope tracking transmitter for base-station and mobile applications

In this paper, we propose enhanced architectures of an envelope tracking (ET) transmitter. For base-station applications, high efficient ET transmitter architectures are implemented using optimized power amplifier (PA) with a 2-bit envelope amplifier (EA) and a multi-biased linear EA. In addition, fully integrated multi-band/multi-mode ET transmitter is implemented using a multi-band PA incorporating an integrated on-chip linearizer with a multi-mode dual-switching EA for mobile applications. ET transmitters that achieve an overall efficiency as high as 47.8% in 10MHz LTE base-station and 28% in 5MHz LTE mobile applications are presented.