MMIC PAM applied with predistorter having independent operation of nonlinear signal

Abstract

A dynamic pre-distorter with two paths to set nonlinear signal level and phase encourages power amplifier module (PAM) for wireless broadband (Wibro) service to enhance linearity. We proposed a linearizer having a new IM generator, which is made tip of the InGaP/ GaAs HBT operated at saturation region of a common collector circuit. The targeted Wibro PAM is designed using InGaP/GaAs HBT technology, and the pre-distorter, drive and power amplifier are fully integrated in single chip within 960 X 2400 mu m. Even though PAM is designed to have just a 5-dB back-off, PAM is compatible with linearity standards up to maximum output power 21 dBm, and has a 17.5% efficiency by having a low leakage and improving spurious of 6 dB in the 64QAM form based on IEEE802.16e-2005 standards. (c) 2008 Wiley Periodicals, Inc.