A 6 Watt linear RF power amplifier for WiMAX base station

This paper presents a two-stage design of a 6 watt RF linear power amplifier following WiMAX radio interface specification. The main design goal chosen is linearity instead of efficiency. By this reason the design must be complemented with a predistortion scheme. The main source of nonlinear impairment, i.e., 3rd-order intermodulation distortion product obtained is below -32 dBc, with a minimum ripple of 0.5 dB over a 150 MHz of bandwidth centered at 2.4 GHz. Due to the specified bandwidth, the DC decoupling filters and input-output matching networks are implemented mainly with microstrip components in both stages. A total gain of 27 dB was measured, which makes this amplifier able to be interconnected directly to low power baseband signal processors.