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격자 부호화 3차원 직교 주파수분할다중화 시스템

A Trellis-Coded 3-Dimensional OFDM System

  • Li, Shuang (Department of Electrical and Electronic Engineering, Gyeongsang National University) ;
  • Kang, Seog Geun (Department of Semiconductor Engineering, Gyeongsang National University)
  • 투고 : 2017.07.12
  • 심사 : 2017.07.24
  • 발행 : 2017.09.30

초록

본 논문에서는 격자 부호화 3차원 직교 주파수분할다중화 시스템을 제시하고 성능을 분석한다. 여기서는 격자 부호화를 위한 3차원 신호성상도에 대한 집합분할 기법도 제시한다. 부호율이 R = 1/3과 2/3인 회귀 체계적 컨볼루션 부호와 3차원 8진 성상도를 이용하여 격자 부호화된 제안된 시스템은 부호화되지 않은 직교 주파수분할다중화 시스템에 비하여 최대 7.8 dB까지 오류성능이 향상될 수 있음을 이론적으로 계산하였다. 또한 컴퓨터 모의실험을 통하여 제시된 이론적 분석과 거의 일치하는 결과를 도출함으로써 이론적 분석이 정확한 것을 확인하였다. 따라서 제안된 격자 부호화 3차원 직교 주파수분할다중화 시스템은 대역폭의 증가 없이 고품질 디지털 전송을 달성할 수 있는 효과적인 방법인 것으로 사료된다.

In this paper, a trellis-coded 3-dimensional (3-D) orthogonal frequency division multiplexing (OFDM) system is presented and its performance is analyzed. Here, a set-partitioning technique for trellis coding with respect to a 3-D signal constellation is also presented. We show theoretically that the proposed system, which exploits a trellis coding scheme with recursive systematic convolutional codes (RSC) of code rate R = 1/3 and 2/3, can improve symbol error rate (SER) up to 7.8 dB as compared with the uncoded OFDM system in an additive white Gaussian noise (AWGN) channel. Computer simulation confirms that the theoretical analysis of the proposed system is very accurate. It is, therefore, considered that the proposed trellis-coded 3-D OFDM system is well suited for the high quality digital transmission system without increase in the available bandwidth.

키워드

참고문헌

  1. C. B. Schlegel and L. C. Perez, Trellis and Turbo Coding, Hoboken, NJ: IEEE Press, 2014.
  2. G. Ungerboeck, "Trellis-coded modulation with redundant signal sets, Part I: Introduction," IEEE Communication Magazine, vol. 25, no. 2, pp. 5-11, Feb. 1987. https://doi.org/10.1109/MCOM.1987.1093542
  3. Z. Chen, E. C. Choi, and S. G. Kang, "Closed-form expressions for the symbol error probability of 3-D OFDM," IEEE Communications Letters, vol. 14, no. 2, pp. 112-114, Feb. 2010. https://doi.org/10.1109/LCOMM.2010.02.091347
  4. S. G. Kang, Z. Chen, J. Y. Kim, J. S. Bae, and J.-S. Lim, "Construction of higher-level 3-D signal constellations and their accurate symbol error probabilities in AWGN," IEEE Transactions on Signal Processing, vol. 59, no. 12, pp. 6267-6273, Dec. 2011. https://doi.org/10.1109/TSP.2011.2165062
  5. S. Li and S. G. Kang, "Design of 3-dimensional cross-lattice signal constellations with increased compactness," Journal of the Korea Institute of Information and Communication Engineering, vol. 20, no. 4, pp. 715-720, Apr. 2016. https://doi.org/10.6109/jkiice.2016.20.4.715
  6. H. C. Kwon and S. G. Kang, "Performance of a 3-dimensional signal transmission system," Journal of the Korea Institute of Information and Communication Engineering, vol. 20, no. 11, pp. 2021-2026, Nov. 2016. https://doi.org/10.6109/jkiice.2016.20.11.2021
  7. J. Zhao, "DFT-based offset-QAM OFAM for optical communications," Optics Express, vol. 22, no. 1, pp. 1114-1126, Jan. 2014. https://doi.org/10.1364/OE.22.001114
  8. L. Deng, X. Wang, C. Zhou, M. Tang, S. Fu, M. Zhang, P. Ping, and D. Liu, "Experimental demonstration of a 16.27 Gb/s 2-D coherent optical OFDM system with 3-D signal mapper and 2-D IFFT modulator," Journal of Lightwave Technology, vol. 34, no. 4, pp. 1177-1183, Feb. 2016. https://doi.org/10.1109/JLT.2015.2506649