Journal of the Institute of Electronics Engineers of Korea TC (대한전자공학회논문지TC)

The Institute of Electronics and Information Engineers (대한전자공학회)
권호 표지

Frequency Efficient CDD-DF-Relay schemes for MC-CDMA Systems

MC-CDMA 시스템에 대한 주파수 효율적인 CDD-DF-Relay 기법에 관한 연구

  • Ko, Kyun-Byoung (Control and Instrumentation Engineering at Chungju National University) ;
  • Woo, Choong-Chae (Electronics, Computer and Communication Engineering at Hanseo University)
  • Received : 2010.10.27
  • Accepted : 2011.05.17
  • Published : 2011.05.25
Download PDF
⟨ Previous Next ⟩

Abstract

In this paper, CDD(Cyclic Delay Diversity)-DF(Decode-and-Forward)-Relay scheme is proposed for MC-CDMA(Multicarrier-Code Division Multiple Access) systems over multipath Rayleigh fading channels. The advantages of general DF schemes come at the expense of the spectral efficiency since the source and all the relays must transmit on orthogonal channels. In order to mitigate this disadvantage of general DF schemes, we have applied CDD techniques to each relays so that all the relays can transmit on single channel. It means that all R-D link channels can be considered as a single channel which is widely delay spread. Namely, it causes the increasing the number of multipath so that the frequency diversity gain can be achieved in MC-CDMA systems. By simulations, we have compared proposed one with general DF scheme. Therefore, it is confirmed that the proposed one can be a possible solution to achieve cooperative diversity gain without a reduction of spectral efficiency.

본 논문에서는 CDD-DF-Relay 기법을 MC-CDMA 시스템에 대해 제안하고 제안된 기법의 성능을 다중경로 레일리 페이딩 채널에서 검증한다. 일반적인 DF-Relay 기법에서는 모든 Relay들이 직교 채널들로 신호를 전송하여야 하기 때문에 그 장점 즉, 다이버시티 이득은 주파수 효율의 저하로부터 얻어진다고 할 수 있다. 따라서 이러한 주파수 효율 저하의 문제점을 해결하기 위하여 본 논문에서는 CDD 기법을 각 Relay 노드에 적용하여 모든 Relay가 하나의 채널만을 사용하도록 한다. 이는 Destination에서 바라본 하나의 R-D 링크 채널의 Delay Spread가 길어지는 효과를 갖는다. 즉 Relay 개수의 증가에 따라 다중 경로수가 증가됨을 의미하고, 이는 MC-CDMA 시스템에서 주파수 다이버시티 이득으로 해설될 수 있다. 모의실험에서는 일반적인 DF-Relay 기법과 제안된 CDD-DF-Relay 기법의 성능을 비교 분석한다. 이를 통해 제안된 기법이 주파수 효율의 저하없이 협력 다이버시디 이득을 획득할 수 있음을 확인하였다.

Keywords

References

  1. J. N. Laneman, D.N.C. Tse, and G. W. Wornell, "Cooperative diversity in wireless networks: efficient protocols and outage behavior," IEEE Trans. Inform. Theory., vol. 50, no. 12, pp. 3063-3080, Dec. 2004.
  2. T. Wang, A. Cano, G. B. Giannakis, and J. N. Laneman, "High-Performance Cooperative Demodulation With Decode-and-Forward Relays," IEEE Trans. on Comm., vol. 55, no. 7, pp. 1427-1438, July. 2007. https://doi.org/10.1109/TCOMM.2007.900631
  3. A. bletsas, H. Shin, M. Z. Win, and A. Lippman, "A simple cooperative diversity method based on network path selection," IEEE J. of Selected Areas in Comm., vol. 24, no. 3, pp. 659-672, Mar. 2006.
  4. S. S. Ikki, and M. H. Ahmed. "Performance Analysis of Adaptive Decode-and-Forward Cooperative Diversity Networks with Best-Relay Selection," IEEE Trans. on Comm., vol. 58, no. 1, pp. 68-72, Jan. 2010. https://doi.org/10.1109/TCOMM.2010.01.080080
  5. M. O. Hasna and M.-S. Alouini, "End-to-End performance of transmission systems with relays over Rayleigh-fading channels," IEEE Trans. Wireless Commun., vol. 2, no. 6, pp. 1126-1131, Nov. 2003. https://doi.org/10.1109/TWC.2003.819030
  6. A. Wittneben, "A new bandwidth efficient transmit antenna modulation diversity scheme for linear digital modulation," in Proceedings IEEE ICC 1993, Geneva, Switzerland, May 1993, pp. 1630-1634.
  7. S. Kaiser, "Spatial transmit diversity techniques for broadband OFDM systems," in Proceedings IEEE GLOBECOM 2000, San Francisco, USA, Nov. 2000, pp. 1824-1828.
  8. S. Plass, A. Dammann, and S. Sand, "An Overview of Cyclic Delay Diversity and its Applications," in Proceedings IEEE VTC 2008, pp. 1-5, 21-24 Sept. 2008.
  9. Y. Zhang, J. Cosmas, K.-K. Loo, M. Bard, and R. D. Bari, "Analysis of Cyclic Delay Diversity on DVB-H Systems over Spatially Correlated Channel," IEEE Trans. on Broadcasting, vol. 53, no. 1, pp. 247-255, Mar. 2007. https://doi.org/10.1109/TBC.2007.891702
  10. Yue Zhang, C. Zhang, J. Cosmas, K. K. Loo, T. Owens, R. D. Di Bari, Y. Lostanlen, and M. Bard, "Analysis of DVB-H Network Coverage With the Application of Transmit Diversity," IEEE Trans. on Broadcasting, vol. 54, no. 3, pp. 568-577, Sep. 2008. https://doi.org/10.1109/TBC.2008.2002165
  11. 고균병, 우중재, "비동기 MC-CDMA 상향 링크 시스템에서의 시간 옵셋 영향 분석," 전자공학회논문지, 제47권, TC편, 제8호, 1-8쪽, 2010년 8월.
  12. 고균병, 우중재, "비동기 MC-CDMA 상향 링크 시스템에서의 잔류 주파수 옵셋 영향 분석," 전자공학회논문지, 제47권, TC편, 제8호, 9-15쪽, 2010년 8월.
  13. John G. Proakis, Digital Communication. McGraw Hill, 1995.
  14. J. F. Helard, J. Y. Baudais, and J. Giterne, "Linear MMSE detection techniques for MC-CDMA," ELECTRONICS LETTERS, vol. 36, no. 7, pp. 665-666, Mar. 2000. https://doi.org/10.1049/el:20000532
  15. Keli Zhang, Yong Liang Guan, and Qinghua Shi, "Complexity Reduction for MC-CDMA With MMSEC," IEEE Trans. on Vehicular Tech., vol. 57, no. 3, pp. 1989-1993, May 2008. https://doi.org/10.1109/TVT.2007.909294
  16. A. Klein, G. K. Kaleh, and P. W. Baier, "Zero forcing and minimum-mean-square-error equalization for multiuser detection in code division multiple access channels," IEEE Trans. on Vehicular Tech., vol. 45, no. 2, pp. 276-287, May 1996. https://doi.org/10.1109/25.492851