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

The Institute of Electronics and Information Engineers (대한전자공학회)
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Outage Performance of Cooperative Cognitive Wireless Relay Networks with Delayed CSI

CSI 지연이 있는 상황 인지 무선 협동 릴레이 네트워크의 오수신율

  • 김남수 (청주대학교 전자정보공학부)
  • Published : 2009.06.25
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Abstract

The performance of a cognitive radio system with cooperative diversity which includes the direct and indirect path is analysed. The selection relay cooperation which selects the best relay, the relay with the best received signal-to-noise ratio(SNR) in destination node, is considered and derived the performance degradation caused by the CSI(Channel State Information) delay analytically. Numerical examples show that the cooperative diversity which have the direct and the indirect paths effectively improves the system performance in Rayleigh fading; the performance improves 4.4 dB with 1/10 of SNR of the indirect path. And the system performance is more degraded with the less frequency acquisition probability and with the high CSI delay.

본 논문에서는 최근에 활발한 연구가 진행되고 있는 상황인지 무선시스템을 대상으로 하여, 직접 경로 및 간접 경로를 갖는 협동 다이버시티를 적용하였을 경우 시스템의 성능을 분석하였다. 그리고 릴레이-목적지 경로에서는 여러 개 의 릴레이 중 가장 큰 신호 대 잡음비를 갖는 릴레이만 송신하는 선택 릴레이 방식을 채택하였고, 이 릴레이를 선택하기 위하여 필수적으로 발생되는 채널 상태정보(CSI) 지연에 의한 시스템 성능의 열화를 포함한 식을 유도하였다. 분석결과 직접 경로로부터의 수신 전력이 간접경로 수신 전력의 1/10만 있어도 시스템의 성능이 4.4 dB 개선되므로 Rayleigh 페이딩 환경 하에서 협동 다이버시티의 적용이 매우 효과적임을 알 수 있었고, 상황 인지 시스템의 주파수 획득 확률이 적을수록, 그리고 채널 지연이 클수록 시스템의 성능은 저하되었다.

Keywords

References

  1. 1. M. Sherman, A. Mody, R. Martinez, C. Rodriguez, and R. Reddy, "IEEE standards supporting cognitive radio and networks, Dynamic spectrum access, and coexistence," IEEE Communication Magazine, vol. 46, no. 7, pp. 72-79, July 2008 https://doi.org/10.1109/MCOM.2008.4557045
  2. A. Ghasemi, and E. Sousa, 'Collaborative spectrum sensing for opportunistic access in fading environments,' Proceedings of DYSPAN2005, pp. 131-136, Nov. 2005
  3. Y. Xing and R. Chandramouli, "Human behavior inspired cognitive radio network design," IEEE Communication Magazine, vol. 46, no. 12, pp. 122-127, Dec. 2008 https://doi.org/10.1109/MCOM.2008.4689219
  4. N. C. Beaulieu and J. Hu, "A closed-form expression for the outage probability of decode-and-forward relaying in dissimilar Rayleigh fading channels," IEEE Communications Letters, vol. 10, no. 12, pp. 813-815, Dec. 2006 https://doi.org/10.1109/LCOMM.2006.061048
  5. Y. Zhao, R. Adve, and T. J. Lim, "Outage probability at arbitrary SNR with cooperative diversity," IEEE Communications Letters, vol. 9, no. 8, pp. 700-702, Aug. 2005 https://doi.org/10.1109/LCOMM.2005.1496587
  6. J. N. Laneman and G. W. Wornell, "Distributed space-time-coded protocols for exploiting cooperative diversity in wireless networks," IEEE Tans. Inf. Theory, vol. 49, no. 10, pp. 2415-2425, Oct. 2003 https://doi.org/10.1109/TIT.2003.817829
  7. A. Bletsas, H. Shin, and M. Z. Win, "Cooperative communications with outage-optimal opportunistic relaying," IEEE Trans. on Wireless Communications, vol. 6, no. 9, pp. 3450-3460, Sep. 2007 https://doi.org/10.1109/TWC.2007.06020050
  8. B. Zhao and M. C. Valent, "Practical relay networks: A generalization on hybrid-ARQ," IEEE Journal on Selected Areas in Communications, vol. 23, no. 1, pp. 7-18, Jan. 2005 https://doi.org/10.1109/JSAC.2004.837352
  9. J. L. Vicario, A. Morell, A. Bel, and G. S-Granados, 'Optimal power allocation in opportunistic relaying with outdated CSI,' Proceedings of Sensor array and Multichannel Signal Processing Workshop (SAM), pp. 49-53, July 2008
  10. J. L. Vicario and C. A-Haro, 'Analytical assessment of multi-user vs. special diversity trade-offs with delayed channel state information,' IEEE Communications Letters, vol. 10, no. 8, pp. 588-590, Aug. 2006 https://doi.org/10.1109/LCOMM.2006.1665119
  11. K. Lee, and Aylin Yener, 'Outage performance of cognitive wireless relay networks,' Proceedings of Globecom2006, pp. 1-5, Nov. 2006
  12. H. A. Suraweera, P. J Smith, and N. A. Surobhi, 'Exact outage probability of cooperative diversity with opportunistic spectrum access,' Proceedings of International Conference on Communication Workshops (ICC2008), pp. 79-84, May 2008
  13. F. Digham, M-S Alouini, and M. K. Simon, "On the energy detection of unknown signals over fading channels," IEEE Trans. on Communications, vol. 55, no. 1, pp. 21-24, Jan. 2007 https://doi.org/10.1109/TCOMM.2006.887483
  14. T. Cover and J. Thomas, Element of information theory, JohnWiley&Sons, Inc., 1991