A Pilot Symbol Based Coherent QAM Decoder for a Wireless Channel

파일럿 패턴을 이용한 무선 QAM 송수신 기술 연구

  • 김한일 (명지대 정보통신공학과) ;
  • 한재충 (명지대 전자정보통신공학과)
  • Published : 2001.08.01

Abstract

Quadrature Amplitude Modulation(QAM) is well known a bandwidth efficient modulation scheme. However, its use for mobile communications has been limited due to noise and signal distortion. Recently, the QAM scheme is emerging as a new modulation scheme for a band-limited wireless system. In this paper, we propose an iterative decoding algorithm assuming QAM signal for a narrow-band mobile channel. The Algorithm is based on the EM(Expectation Maximization) Algorithm, and the performances of the proposed decoder are assessed using computer simulation. The simulation results show that the proposed decoder perform better compared to that of other schemes.

Keywords

References

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