A Novel N-way Distributed Doherty Amplifier with Improved Efficiency at High PAR Signals

摘要

A novel three-way distributed Doherty power amplifier, with improved efficiency at high peak-to-average ratio (PAR) signals such as W-CDMA and OFDM, is presented. This distributed Doherty amplifier consists of one main amplifier and two peaking amplifiers. In order to improve the efficiency at a high back-off power, the peaking amplifier structure is based on a dual-fed distributed amplifier form. The results of the three-way distributed Doherty amplifier, measured at 2140 MHz, produced a power gain of 11 dB. At that point, a power-added efficiency (PAE) of 39.5 percent was measured for a 9.5 dB PAR signal. A high linearity performance of-54 dBc AC PR is achieved after using memory-compensated digital predistortion.