Correcting nonlinear distortion of wideband modulated signals using new frequency domain methods
Sam Kusano, Augustine Stav, Tong Li, Jan Verspecht
Abstract
Distortion -less wideband modulated test signals are generated at high power using a new frequency domain method, called spectral digital pre-distortion (Spectral DPD). This technique extends the power range of signal generators, reducing the need for booster power amplifiers to achieve a good linearity, high-power signal for test The proposed technique first creates a short slice of the modulated waveform for fast and accurate linearization of the signal at the reference plane. Then, using a pre-distorted waveform created by spectral DPD, a generic memory-polynomial DPD model is identified. This model is then applied to the original waveform to generate a pre-distorted waveform, providing a linearized test signal. An example 5GNR test signal is demonstrated for linearization.