The Journal of Korean Institute of Communications and Information Sciences (한국통신학회논문지)

The Korean Institute of Commucations and Information Sciences (한국통신학회)
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New Simplified Sum-Product Algorithm for Low Complexity LDPC Decoding

복잡도를 줄인 LDPC 복호를 위한 새로운 Simplified Sum-Product 알고리즘

  • 한제희 (한국전자통신연구원 방송통신융합연구부문 위성무선융합연구부 위성방통융합연구팀) ;
  • 선우명훈 (아주대학교 정보통신대학 전자공학부 SoC 연구실)
  • Published : 2009.03.31
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Abstract

This paper proposes new simplified sum-product (SSP) decoding algorithm to improve BER performance for low-density parity-check codes. The proposed SSP algorithm can replace multiplications and divisions with additions and subtractions without extra computations. In addition, the proposed SSP algorithm can simplify both the In[tanh(x)] and tanh-1 [exp(x)] by using two quantization tables which can reduce tremendous computational complexity. Moreover, the simulation results show that the proposed SSP algorithm can improve about $0.3\;{\sim}\;0.8\;dB$ of BER performance compared with the existing modified sum-product algorithms.

본 논문은 BER 성능을 높인 LDPC 복호를 위한 새로운 SSP 알고리즘을 제안한다. 제안하는 SSP 알고리즘은 추가적인 연산 없이 곱셈 연산과 나눗셈 연산을 덧셈 연산과 뺄셈 연산으로 대체가 가능하다. 제안하는 SSP 알고리즘은 In[tanh(x)] 함수와 $tanh^{-1}[exp(x)]$ 함수를 각각의 양자화 테이블을 사용하여 단순화하기 때문에 연산 복잡도를 줄일 수 있다. 시뮬레이션 결과 제안하는 SSP 알고리즘은 기존의 근사화 SP 알고리즘과 비교하여 BER 성능을 $0.3\;{\sim}\;0.8\;dB$ 향상시킨 것을 보여준다.

Keywords

References

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