A 500-W high efficiency LDMOS classical three-way Doherty amplifier for base-station applications

A 500W classical three-way Doherty power amplifier (DPA) with LDMOS devices at 1.8GHz is presented. Optimized device ratio is selected to achieve maximum efficiency as well as linearity. With a simple passive input driving network implementation, the demonstrator exhibits more than 55% efficiency with 9.9PAR WCDMA signal from 1805MHz–1880MHz. It can be linearized at −60dBc level with 20MHz LTE signal at an average output power of 49dBm.