A Multi-Mode Envelope Tracking Power Amplifier for Software Defined Radio Transmitters

A multi-mode envelope tracking power amplifier is presented for software defined and cognitive radio solutions. A new 0.13um CMOS hysteretic-controlled hybrid switching supply modulator is developed for the mode dependent operation of the power supply modulator. Combined with 1.88GHz HBT class-AB/F PA operating with novel envelope shaping method, the proposed envelope tracking power amplifier shows high efficiency and linearity over broad output power range. It achieves the PAE of 45/46/34.3% at the average output power of 27.8/29/23.9dBm for EDGE/WCDMA/ Mobile-WiMax, respectively, while satisfying the linearity specification without any digital pre-distortion technique. There are about 7% and 3% improvements of the overall PAE for EDGE and WCDMA, respectively, through the adaptive multi-mode operation.