A High Power Asymmetric Doherty Amplifier with Improved Linear Dynamic Range

Abstract

An asymmetric high power extended Doherty amplifier, which has the extended peak efficiency over a 9-dB of output power and a linear dynamic range is presented in this paper. The power amplifier is designed by using two different LDMOS FET's for W-CDMA base station applications. To realize the peak efficiency extension and a linear dynamic range, a two times larger peaking device compared to the main device, and an unequal power divider is used. This asymmetric Doherty amplifier obtained a measured P1dB of 49.8 dBm. An efficiency of 31.1 % and an ACLR of -35 dBc are achieved at 9 dB back-off point, respectively