Journal of the Korea Society of Computer and Information (한국컴퓨터정보학회논문지)

Korean Society of Computer Information (한국컴퓨터정보학회)
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Study on DPSAM Turbo TCM in Time-Selective Fading Channels

시간 선택적 페이딩 채널 환경에서 DPSAM Turbo TCM에 관한 연구

  • Kim, Jeong-Su (Dept. of Computer, Information & Communication, Korea Soongsil Cyber University)
  • 김정수 (숭실사이버대학교 컴퓨터정보통신학과)
  • Received : 2013.07.29
  • Accepted : 2013.10.15
  • Published : 2013.11.29
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Abstract

Mobile mobility and data reliability should be guaranteed as well as amounts of data services are essential in the era of smart media. In order to improve the reliability of high-speed data, strong channel coding and modulation techniques are required. In this paper, the structure of Turbo TCM decoder, applying high-order modulation techniques and the DPSAM method which improves performances in time-selective fading channels in the case of burst errors are suggested through the optimal decoding method and iteration decoding so as to improve bandwidth efficiency in Turbo Codes with excellent encoding gain. The proposed method in comparison with the existing method is that 3dB is superior in case that BER is $10^{-2}$ and the number of iterations is 3. In addition, the function is improved at approximately 6dB in case that BER is $10^{-3}$ and the number of iterations is 7. The proposed method requires additional bandwidth; however, the bandwidth loss can be overcome through Turbo TCM technology on the additional bit rate from the bandwidth loss.

스마트 미디어 시대에 대용량 데이터 서비스가 필수적이고 모바일 이동성과 데이터 신뢰성이 보장되어야 한다. 고속 데이터의 신뢰성을 높이기 위해서는 강력한 채널 코딩 방식 및 변조 기술이 요구되고 있다. 본 논문에서는 최적 복호 방법, 반복 복호를 통하여 부호화 이득이 우수한 Turbo Codes에 대역폭 효율을 증대시키기 위한 고차 변조기술을 적용한 Turbo TCM 복호기의 구조를 제시하고 시간 선택적 페이딩 채널 환경에서 연집에러 발생 시 성능을 향상시키는 DPSAM 방식에 대해 제안하다. 제안된 방식은 기존의 방식과 비교해서 BER이 $10^{-2}$이고 반복 복호수가 3인 경우 약 3dB 우수하고 BER이 $10^{-3}$이고 반복 복호수가 7인 경우 약 6dB 성능 개선을 보인다. 제안된 방식은 추가 대역폭이 필요하지만 대역폭 손실에서 발생하는 부가 비트율에 대해 Turbo TCM 기술로 대역폭 손실을 극복할 수 있다.

Keywords

References

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