OFDM 통신 시스템에서 PAPR을 줄이기 위한 적은 계산 복잡도를 갖는 PTS 방법

A New PTS OFDM Scheme with Low Complexity for PAPR Reduction

  • 임대운 (서울대학교 전기.컴퓨터공학부) ;
  • 허석중 (서울대학교 전기.컴퓨터공학부) ;
  • 노종선 (서울대학교 전기.컴퓨터공학부) ;
  • 정하봉 (홍익대학교 전기전자공학부)
  • 발행 : 2006.09.01

초록

본 논문은 직교 주파수 분할 다중화(OFDM) 통신 시스템에서 최대 전력 대 평균 전력의 비 (PAPR)를 감소하기 위해서 사용되는 새로운 부분 전송 시퀀스(PTS) 기법을 제안한다. 제안하는 방법에서는 역 푸리에 변환(IFFT)을 두 부분으로 나누어 실행한다. 첫 번째 부분에서는 IFFT를 중간까지만 수행하여 입력 심볼 시퀀스를 중간 신호 시퀀스로 변환한다. 두 번째 부분은 중간 신호 시퀀스를 여러 개의 서브 시퀀스로 분할한 후 각각에 대해서 나머지 IFFT를 완료하고 PAPR을 감소하기 위한 위상 벡터를 선택한다. 본 논문에서 제안하는 PTS 기법은 기존의 PTS 기법과 유사한 PAPR 감소 성능을 보이지만 계산 복잡도를 감소시킨다.

In this paper, we introduce a new partial transmit sequence (PTS) orthogonal frequency division multiplexing (OFDM) scheme with low computational complexity. In the proposed scheme, $2^n$-point inverse fast Fourier transform (IFFT) is divided into two parts. An input symbol sequence is partially transformed using the first l stages of IFFT into an intermediate signal sequence and the intermediate signal sequence is partitioned into a number of intermediate signal subsequences. Then, the remaining n - l stages of IFFT are applied to each of the intermediate signal subsequences and the resulting signal subsequences are summed after being multiplied by each member of a set of W rotating vectors to yield W distinct OFDM signal sequences. The one with the lowest peak to average power ratio (PAPR) among these OFDM signal sequences is selected for transmission. The new PTS OFDM scheme reduces the computational complexity while it shows almost the same performance of PAPR reduction as that of the conventional PTS OFDM scheme.

키워드

참고문헌

  1. M Breiling, S. H. MillIer, and J. B. Huber, 'SLM peak power reduction without explicit side information,' IEEE Commun. Lett., vol. 5, no. 6, pp. 239 - 241, June 2001 https://doi.org/10.1109/4234.929598
  2. J. A. Davis and J. Jedwab, 'Peak-to-mean power control in OFDM, Golay complementaly sequences, and Reed-Muller codes,' IEEE Trans. Inform, Theory, vol. 45, no. 7, pp. 2397 -2417, Nov. 1999 https://doi.org/10.1109/18.796380
  3. P. V. Eetvelt, G. Wade, and M Tomlinson, 'Peak to average power reducing for OFDM schemes by selective scrambling,' IEEE Electron. Lett., vol. 32, no. 21, pp. 1963 - 1964, Oct. 1996 https://doi.org/10.1049/el:19961322
  4. S. G. Kang and J. G. Kim, 'A novel subblock partition scheme for partial transmit sequence OFDM,' IEEE Trans. Broadcast., vol. 45, no. 3, pp. 333 - 338, Sept. 1999 https://doi.org/10.1109/11.796276
  5. S. H. Muller, R. W. Bauml, R. F. H. Fischer, and J. B. Huber, 'OFDM with reduced peak-to-average power ratio by multiple signal representation,' In Annals of Telecommun., vol. 52, no. 1 - 2, pp. 58 - 67, Feb. 1997
  6. X. Wang, T. T. Tjhung, and C. S. Ng, 'Reduction of peak to average ratio pf OFDM system using a companding technique,' IEEE Trans. Broadcast., vol. 45, no. 3, pp. 303 - 307, Sept. 1999 https://doi.org/10.1109/11.796272
  7. T. Jiang and G. Zhu, 'Nonlinear companding transform for reducing peak-to-average power ratio of OFDM signals,' IEEE Trans. Broadcast., vol. 50, no. 3, pp. 342 - 346, Sept. 2004 https://doi.org/10.1109/TBC.2004.834030
  8. D. -W. Lim, S. -J. Heo, J. -S. No, and H. Chung, 'A new SLM OFDM scheme with low complexity for PAPR reduction,' IEEE Signal Processing Lett., vol. 12, no. 2, pp. 93 - 96, Feb. 2005 https://doi.org/10.1109/LSP.2004.840915