A 2-way symmetrical Doherty power amplifier (PA) with high efficiency is presented. This amplifier delivers 49.2 dBm (83 W) of saturated output power and 63% drain efficiency with 38.2 dB of power gain at 460MHz. The drain efficiency at 6 dB backed-off power level shows about 62%. After digital pre-distortion (DPD) system corrected, about 48% power-added efficiency (PAE) at 42.2 dBm (16.6 W) average output power has been demonstrated, while achieving -52 dBc (-28 dBc before linearization) Adjacent Channel Leakage Ratio (ACLR) at 20 MHz offset using a LTE-Advanced input signal with 6.5 dB peak to average ratio (PAR) to meet the IMT-Advanced system requirements. We also used a π type structure network based on lumped elements to replace the traditional Doherty amplifier 1/4λ transmission line, and compared the performance.
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