CDMA handset power amplifier with diode load modulator

A new monolithic PA for 836 MHz CDMA cellular phone is developed using a simple diode based load modulator at the output matching circuit. The modulation network allows power level dependent load impedances for better power-added efficiencies. Especially, the PAE at the lower output power range, less than 10 dBm where most of handset operation arises, is increased more than 80%.

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