The Journal of Korean Institute of Communications and Information Sciences (한국통신학회논문지)

The Korean Institute of Commucations and Information Sciences (한국통신학회)
권호 표지
DOI QR코드

DOI QR Code

Degrees of Freedom for MIMO Z-Interference Channels with Reconfigurable Antennas in the Absence of CSIT

송신단 채널 정보가 없는 재구성 안테나를 사용한 다중입출력 Z-간섭 채널에서의 자유도

  • Yang, Heecheol (Department of Electrical and Computer Engineering, INMAC, Seoul National University) ;
  • Lee, Jungwoo (Department of Electrical and Computer Engineering, INMAC, Seoul National University)
  • Received : 2016.09.22
  • Accepted : 2017.01.05
  • Published : 2017.02.28
Download PDF
⟨ Previous Next ⟩

Abstract

In this paper, we derive the achievable degrees of freedom (DoF) for multiple-input multiple-output (MIMO) Z-interference channels (Z-IC) with reconfigurable antennas at the receivers, assuming that channel state information is not available at the transmitters. We propose a new linear scheme to align interfering signals and to decode desired signals through the designed preset mode switching pattern of reconfigurable antennas at the receivers. The key idea of our scheme is to use interfering signals as a side information at the interfered receiver by being silent at the corresponding transmitter during some time slots. Consequently, it is shown that the reconfigurable antennas at the receivers can bring a DoF gain if the number of preset modes is greater than the number of RF chains at the receivers.

본 논문에서는 송신단 채널 정보가 없는 다중안테나 Z-간섭 채널에서 수신단의 재구성 안테나를 통해 얻을 수 있는 자유도(DoF: degrees of freedom) 이득을 구한다. 수신단이 가지는 재구성 안테나의 안테나 모드 스위칭 패턴 디자인을 통해 간섭 신호는 정렬하고 원하는 신호를 위해 충분한 신호부공간(signal subspace)을 남겨두는 새로운 선형 기법을 제안한다. 제안하는 기법의 핵심은 송신단에서 일정 구간동안 신호를 보내지 않음으로써 수신단에서 그 동안 받은 간섭신호를 부가 정보(side information)로 간섭 제거에 활용하는 것이다. 결론적으로, 수신단이 가지는 재구성 안테나를 활용해 재구성 안테나 모드의 개수가 RF 체인의 수 보다 클 때 더 큰 자유도 이득을 얻을 수 있음을 밝힌다.

Keywords

References

  1. V. Cadambe and S. A. Jafar, "Interference alignment and degrees of freedom of the K-user interference channel," IEEE Trans. Inf. Theory, vol. 54, no. 8, pp. 3425-3441, Aug. 2008. https://doi.org/10.1109/TIT.2008.926344
  2. S. -W. Jeon and B. C. Jung, "Interference neutralization for small-cell wireless networks," J. KICS, vol. 38, no. 12, pp. 1117- 1124, Dec. 2013.
  3. K. Kim, S. -W. Jeon, J. Yang, and D. K. Kim, "Feasibility of interference alignment for reverse duplex in MIMO cellular networks with one-side base coopertation," J. KICS, vol. 40, no. 2, pp. 273-284, Feb. 2015. https://doi.org/10.7840/kics.2015.40.2.273
  4. S. -W. Jeon, "Recent study on interference management for full-duplex cellular systems," J. KICS, vol. 40, no. 7, pp. 1266-1275, Jul. 2015. https://doi.org/10.7840/kics.2015.40.7.1266
  5. T. Gou, C. Wang, and S. A. Jafar, "Aiming perfectly in the dark-blind interference alignment through staggered antenna switching," IEEE Trans. Sign. Process., vol. 59, no. 6, pp. 2734-2744, Jun. 2011. https://doi.org/10.1109/TSP.2011.2129517
  6. M. Yang, S. -W. Jeon, and D. K. Kim, "Linear degrees of freedom of MIMO broadcast channels with reconfigurable antennas in the absence of CSIT," arXiv preprint arXiv:1409.5532v1, Sept. 2014. https://doi.org/10.1109/TIT.2016.2623792
  7. Y. Lu, W. Zhang, and K. B. Letaief, "Blind interference alignment with diversity in K-user interference channels," IEEE Trans. Commun., vol. 62, no. 8, pp. 2850-2859, Aug. 2014. https://doi.org/10.1109/TCOMM.2014.2333516
  8. C. Wang, "Degrees of freedom characterization: the 3-user SISO interference channel with blind interference alignment," IEEE Commun. Lett., vol. 18, no. 5, pp. 757-760, May 2014. https://doi.org/10.1109/LCOMM.2014.030714.140177
  9. H. Yang, W. Shin, and J. Lee, "Degrees of freedom for K-user SISO interference channels with blind interference alignment," in Proc. IEEE Asilomar Conf. on Sign., Syst., and Comput., Pacific Grove, CA, Nov. 2015.
  10. M. M. Cespedes, J. P. Chaves, D. Toumpakaris, S. A. Jafar, and A. G. Armada, "Blind interference alignment for cellular networks," IEEE Trans. Sign. Process., vol. 63, no. 1, pp. 41-56, Jan. 2015. https://doi.org/10.1109/TSP.2014.2362104
  11. L. Ke and Z. Wang, "Degrees of freedom regions of two-user MIMO Z and full interference channels: the benefit of reconfigurable antennas," IEEE Trans. Inf. Theory, vol. 58, no. 6, pp. 3766-3779, Jan. 2012. https://doi.org/10.1109/TIT.2012.2185483
  12. K. Mohanty and M. K. Varanasi, "Degrees of freedom of the MIMO Z-interference channel with delayed CSIT," IEEE Commun. Lett., vol. 19, no. 12, pp. 2282-2285, Dec. 2015. https://doi.org/10.1109/LCOMM.2015.2483584
  13. C. Wang, T. Gou, and S. A. Jafar, "Interference alignment through staggered antenna switching for MIMO BC with no CSIT," in Proc. IEEE Asilomar Conf.Signals, Syst., Comput., Pacific Grove, CA, Nov. 2010.