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Compensation of the Non-linearity of the Audio Power Amplifier Converged with Digital Signal Processing Technic

디지털 신호 처리 기술을 융합한 음향 전력 증폭기의 비선형 보상

  • Eun, Changsoo (Department of Radio Information Communications Eng., Chungnam National University) ;
  • Lee, Yu-chil (Kaidas Co., Ltd.)
  • Received : 2016.04.21
  • Accepted : 2016.05.18
  • Published : 2016.06.30

Abstract

We propose a digital signal processing technic that can compensate the non-linearity inherent in audio amplifiers, and present the result of the simulation. The inherent non-linearity of the audio power amplifier arising from analog devices is compensated via a digital signal processing technic consisting of indirect learning architecture and an adaptive filter. The simulation results show that the compensator can be realized using a third-order polynomial and compensates odd-order non-linearity efficiently. The even-oder non-linearity is mainly due to the dc offset at the output, which is difficult to eliminate with the proposed method. Care must be taken in designing the bias circuit to avoid the DC offset at the output. The proposed technic has significance in that digital signal processing technic can compensate for the impairment that is an inherent characteristic of an analog system.

Keywords

Convergence of analog and digital systems;nonlinear compensation;audio amplifier;indirect learning architecture;adaptive filter

Acknowledgement

Supported by : 충남대학교

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