Adaptive Nonlinearity Compensation for Power Amplifiers Based on Model-Matching Approach

A new time-domain adaptive linearization scheme is presented for compensating nonlinearity of high power amplifiers (HPA) in OFDM systems. A power series model with memory (PSMWM) is proposed to approximately describe the nonlinear input-output relation of HPA with dynamics. By using the PSMWM, the compensation input to HPA is calculated in a real-time manner so that the linearization from the predistorter (nonlinearity compensator) input to the HPA output can be attained even if the nonlinear dynamics of HPA is uncertain and changeable. The effectiveness of the proposed adaptive nonlinearity compensation scheme is validated in numerical simulation for 64-ary quadrature amplitude modulation OFDM (64QAM-OFDM) transmission systems.