The Journal of the Institute of Internet, Broadcasting and Communication (한국인터넷방송통신학회논문지)

The Institute of Internet, Broadcasting and Communication (한국인터넷방송통신학회)
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Opportunistic Transmit Cognitive Radio Relay Systems with CSI Delay

CSI 지연을 갖는 기회전송 상황 인지 릴레이 시스템

  • 김남수 (청주대학교 전자정보공학부)
  • Received : 2010.07.12
  • Accepted : 2010.10.15
  • Published : 2010.10.31
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Abstract

In this paper, we analyze the performance of the cooperative cognitive radio relay system which is adapted the recently highly focused cognitive radio system. The performance comparison is made between the system with and that without the opportunistic transmission relay. Especially the selection combining is considered at the destination for simple implementation. In this case, the effect of the channel state information (CSI) delay, which is caused essentially by the process during the CSI delivery, to the system performance is considered. It is noticed that the performance of the system with the opportunistic relay degrades up to 0.6 dB at a given condition compared to the system without the opportunistic relay. And it is shown that the system performance is more sensitive to the CSI delay compared to the frequency acquisition probability of the cognitive radio relay.

본 논문에서는 최근에 많은 주목을 받고있는 상황인지 시스템을 협동릴레이 시스템에 적용하였을 때 상황인지 협동 릴레이 시스템의 성능을 유도하였다. 협동 릴레이 시스템은 기회전송 릴레이를 채택하였을 때와 채택하지 않았을 때의 성능을 비교하였다. 특히 목적지에서 시스템 구현의 간편성 때문에 많이 채택하고 있는 선택 결합방식을 고려하였는데, 이 경우 필수적으로 발생되는 채널 상태 정보(CSI)를 주고받으면서 발생되는 지연의 영향을 고려하였다. 분석결과 기회전송 릴레이를 채택할 경우 기회전송 릴레이를 채택하지 않은 경우보다 주어진 조건에서 최대 0.6 dB 열화 되었으며, 시스템의 성능은 상황인지 릴레이의 주파수 획득 확률보다는 채널 상태정보의 지연에 더욱 민감한 영향을 받음을 알 수 있었다.

Keywords

References

  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.
  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. 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
  5. 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
  6. 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
  7. K. Lee, and Aylin Yener, "Outage performance of cognitive wireless relay networks," Proceedings of Globecom2006, pp. 1-5, Nov. 2006.
  8. 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.