The Journal of the Korea institute of electronic communication sciences (한국전자통신학회논문지)

Korea Institute of Electronic Communication Science (한국전자통신학회)
권호 표지
DOI QR코드

DOI QR Code

Performance of Cooperative Networks with Differential Distributed Modulation using Mixed Signaling Scheme

혼합된 신호 방식을 적용한 차등 분산 변조 협력 네트워크의 성능

  • Cho, Woong (Dept. Computer Engineering, Jungwon University)
  • 조웅 (중원대학교 컴퓨터공학과)
  • Received : 2019.10.29
  • Accepted : 2019.12.15
  • Published : 2019.12.31
Download PDF
⟨ Previous Next ⟩

Abstract

Cooperative networks transmit signals form the source node to the destination node via several relay node where the combining and demodulation of relay aided signals provide the benefit of performance enhancement and data rate increment. In general, a repetitive manner transmission scheme in which the received signal from the source node is amplified/re-generated and forward to the destination node is widely used. In this paper, we analyzed the performance of cooperative networks using the mixed transmission scheme. The conventional modulation scheme is used in the source-relay links, and space-time code is applied in the relay-destination links. To reduce the complexity of the overall system, we adopt differential modulation which bypasses channel state information. We analyze bit error rate (BER) of the proposed system by considering the number of relay nodes, and the performances depending on the strength of transmission signal in the source-relays and rely-destination links are compared. In addition, we also discuss the system performance with the signal strength and the number of relay nodes simultaneously.

협력 네트워크는 송신기로부터 수신기로 신호를 전송할 때 여러 중계기를 이용하여 신호를 전송하고 수신기에서 이 신호를 결합하여 복조함으로써 통신성능 향상과 데이터 전송률을 높이는 장점을 제공한다. 일반적으로 송신기에서 수신기로 신호를 전송할 때 중계기가 송신기로부터 수신된 신호를 증폭/재변조 후 수신기로 보내는 반복적인 신호 전송형태가 널리 사용된다. 본 논문에서는 두 가지 신호전송 방식을 혼합하여 신호를 전송하는 협력 네트워크에서의 성능을 분석한다. 즉, 송신기와 중계기사이에서는 일반 변조방식을 사용하고, 중계기와 수신기 사이에서는 공간 시간 코드 방식을 적용한다. 변조방식은 시스템의 복잡도를 줄이기 위해 채널상태정보를 이용하지 않는 차등변조 방식을 이용한다. 다양한 개수의 중계기가 있을 경우에 대한 성능을 비트오류율을 이용하여 분석하며, 송신기와 중계기 및 중계기와 수신기 사이에서 서로 다른 세기로 신호를 보낼 때의 성능을 비교한다. 또한 다양한 신호세기 및 중계기의 개수를 동시에 고려한 성능에 대해서도 논의한다.

Keywords

References

  1. A. Ribeiro, X. Cai, and G. B. Giannakis, "Symbol error probabilities for general cooperative links," IEEE Trans. Wireless Comm., vol. 4, no. 3, May 2005, pp. 1264-1273. https://doi.org/10.1109/TWC.2005.846989
  2. R. Cao and L. Yang, "The affecting factors in resource optimization for cooperative communications: A case study," IEEE Trans. on Wireless Commun., vol. 11, no. 12, Dec. 2012, pp. 4351-4361. https://doi.org/10.1109/TWC.2012.102612.111845
  3. W. Cho, R. Cao, and L. Yang, "Optimum resource allocation for amplify-and-forward relay networks with differential modulation," IEEE Trans. Signal Processing, vol. 56, no. 11, Nov. 2008, pp. 5680-5691. https://doi.org/10.1109/TSP.2008.926973
  4. W. Cho and H. Cho, "Performance of relay networks with partially differential modulation scheme depending on energy allocation in railway environments," J. of the Korea Institute of Electronic Communication Sciences, vol. 11, no. 1, Jan. 2016, pp. 17-22. https://doi.org/10.13067/JKIECS.2016.11.1.17
  5. W. Cho, B. Kim, and H. Cho, "Performance of downlink with dual-hop communication systems in railway environments," J. of the Korea Institute of Electronic Communication Sciences, vol. 12, no. 1, Feb. 2017, pp. 69-74. https://doi.org/10.13067/JKIECS.2017.12.1.69
  6. W. Cho, "Effect of energy allocation in dual-hop communication systems with DF protocol," IET Electronics Letters, vol. 54, no. 11, 2018, pp. 726-728. https://doi.org/10.1049/el.2018.0557
  7. Y. Jing and H. Jafarhani, "Distributed space-time coding for wireless relay network," IEEE Trans. on Commun., vol. 56, no. 7, July 2008, pp. 1092-1100. https://doi.org/10.1109/TCOMM.2008.060388
  8. G. Wang, Y. Yao, and, G. B. Giannakis, "Non-coherent distributed space-time processing for multiuser cooperative transmission," IEEE Trans. on Wireless Commun., vol. 5, no. 12, Dec. 2006, pp. 3339-3343. https://doi.org/10.1109/TWC.2006.256952
  9. W. Cho "Performance of amplify-and-forward cooperative networks with differential unitary space time coding," Wireless Networks, vol. 17, no. 3, Apr. 2011, pp. 621-627. https://doi.org/10.1007/s11276-010-0301-z
  10. B. M. Hochwald, "Differential unitary space-time modulation," IEEE Trans. on Commun., vol. 48, no. 12, Dec. 2000, pp. 2041-2052. https://doi.org/10.1109/26.891215
  11. M. K. Simon and M. S. Alouini, Digital Communications over Fading Channels. 2nd Ed. New York: Wiley, 2004, Chap. 8.2.