Power amplifier linearization by modified baseband signal injection

摘要

This paper presents the linearization technique for RF power amplifiers that uses the modified baseband signals. The signal for linearization is formed in baseband, digitally processed by adjusting the amplitude and polarity and injected at the input and output of the amplifier transistor across the DC bias circuits. The modified baseband signal is one of the products of the second order nonlinearity of a nonlinear system fed by the useful baseband signal. The effects of the proposed linearization method are considered on a single stage power amplifier for quadrature amplitude modulated signals characterized with different bandwidth up to 200 MHz, as well as for WCDMA digitally modulated signal.