Adaptive Predistortion for High Power Amplifier by Exact Model Matching Approach

  • Ding, Yuanming (Department of Information Engineering, Dalian University) ;
  • Pei, Bingnan (Department of Information Engineering, Dalian University) ;
  • Nilkhamhang, Itthisek (Department of System Design Engineering, Keio University) ;
  • Sano, Akira (Department of System Design Engineering, Keio University)
  • Published : 2004.08.25

Abstract

In this paper, a new time-domain adaptive predistortion scheme is proposed to compensate for the nonlinearity of high power amplifiers (HPA) in OFDM systems. A complex Wiener-Hammerstein model (WHM) is adopted to describe the input-output relationship of unknown HPA with linear dynamics, and a power series model with memory (PSMWM) is used to approximate the HPA expressed by WHM. By using the PSMWM, the compensation input to HPA is calculated in a real-time manner so that the linearization from the predistorter input to the HPA output can be attained even if the nonlinear input-output relation of HPA is uncertain and changeable. In numerical example, the effectiveness of the proposed method is confirmed and compared with the identification method based on PSMWM.