Design of a predistortive high power amplifier using carrier complex power series analysis

In this article, a new carrier complex power series for linearizing the distortion effects of a high power amplifier (HPA) is proposed. The amplitude (AM-to-AM) and phase (AM-to-PM) nonlinear characteristics of the HPA are combined to generate a carrier complex power series. An inverse carrier complex power series for a predistortor is also proposed. An HPA in the IMT-2000 band was fabricated with a measured gain and P _1dB of 34.06 dB and 35.4 dBm, respectively. By using the proposed power series, the carrier-to-intermodulation ratio (C/I) of the HPA is improved by 17.01 dB at an output power of 25.43 dBm per tone with two-tone frequencies at 2.1375 and 2.1425 GHz.