OFDM 신호의 PAPR 감소를 위한 저복잡도의 분할 SLM 기법
Partitioned-SLM with Low Complexity for PAPR Reduction of OFDM Signals
0
조회
0
다운로드
0
인용
0
참고문헌
키워드
초록
본 논문에서는 OFDM (Orthogonal Frequency Division Multiplexing) 전송 신호의 PAPR (Peak-to-Average Power Ratio) 감소를 위한 SLM (SeLective Mapping) 기법의 복잡도를 효과적으로 낮출 수 있는 분할 SLM (Partitioned-SLM; P-SLM) 기법을 제안한다. 제안 기법에서는 기존 SLM 기법에서와는 달리 먼저 주파수 영역 OFDM 심벌을 두 개 이상의 부블록들로 분할하고 이들에 비교적 짧은 길이 및 적은 가짓수를 가진 직교 부호를 곱한 후 IFFT (Inverse Fast Fourier Transform)를 취하여 시간 영역 시퀀스를 생성한 뒤, 이들 중에서 가장 낮은 PAPR을 갖는 부블록 조합을 선택 결합하여 전송한다. 모의실험 결과, 제안 P-SLM 기법은 기존 SLM 기법의 OFDM PAPR 감소 성능을 그대로 유지하면서도 IFFT 수행 횟수 및 곱셈 연산수는 현저히 감소시킬 수 있음을 확인하였다.
Abstract
In this paper, we propose P-SLM (Partitioned-SeLective Mapping) scheme with low complexity for PAPR (Peak-to-Average Power Ratio) reduction of OFDM (Orthogonal Frequency Division Multiplexing) signals. In the proposed scheme, a symbol sequence in the frequency domain is partitioned into several sub-blocks which are multiplied by different orthogonal codes whose length and number are shorter and smaller than those used in the conventional SLM. Then, among various sequences in the time domain generated after the IFFT (Inverse Fast Fourier Transform) for the SLM sub-blocks, the sub-block combination with the lowest PAPR is selected and transmitted. Simulation results show that the proposed P-SLM scheme significantly reduces the number of IFFT calculation and multiplication than the conventional SLM without loss of PAPR reduction performance.
참고문헌 (9)
- R. Prasad, "OFDM for Wireless Communications Systems" (2004), Artech House Publishers
- S. H. Han, "An overview of peak-toaverage power ratio reduction techniques for multicarrier transmission", IEEE Wireless Commun, 12(2), pp.56~65 (2005)
- R. W. Bauml, "Reducing the peak-to-average power ratio of multicarrier modulation by selective mapping", IEE Electr. Lett, 32(22), pp.2056~2057 (1996)
- C. Tellambura, "Computation of the continuous-time PAR of an OFDM signal with BPSK subcarriers", IEEE Commun. Lett, 5(5), pp.185~187 (2001)
- S. H. Han, "Peak-to-average power ratio reduction of an OFDM signal by PAPR reduction sub-carriers", Proc. IEEE APWCS 2004, Seoul, Korea, pp.3~6 (2004)
- E. Lawley, "Peak-to-average power ratio reduction of OFDM signals using peak reduction carriers", Proc. ISSPA '99, Brisbane, Australia, pp.737~740 (1999)
- D. Lim, "A new SLM OFDM scheme with low complexity for PAPR reduction", IEEE Signal Proc. Lett, 12(2), pp.93~96 (2005)
- D. Lim, "On the phase sequence set of SLM OFDM scheme for a crest factor reduction", IEEE Trans. Signal Proc, 54(5), pp.1931~1935 (2006)
- A. V. Oppenheim, "Discrete-Time Signal Processing" (1999), Prentice Hall