Joint cooperative relay scheme for spectrum-efficient usage and capacity improvement in cognitive radio networks

Qixun Zhang1, Zhiyong Feng1, Ping Zhang1
1Wireless Technology Innovation Institute (WTI), Key Laboratory of Universal Wireless Communications Ministry of Education, Information and Telecommunication Engineering of Beijing University of Posts and Telecommunications (BUPT), Beijing, P.R. China

Tóm tắt

In order to improve the efficiency of spectrum resource usage and the capacity of wireless networks, cooperative relay techniques which utilize the vacant spectrum of primary users for secondary users' data transmission have been applied in cognitive radio networks. Considering the dynamic time-varying vacant spectrum resources and achievable rate on different channels at relay nodes (RN), the traditional fixed time slot allocation scheme for cooperative RNs has the bottleneck for further improving the spectrum usage efficiency and system throughput. Therefore, the joint cooperative relay scheme with RN selection, channel allocation and dynamic time slot allocation (DyTSA), is designed to increase the spectrum usage efficiency and system capacity by dynamic tuning DyTSA ratio to adapt to the changing radio environment in multiple RNs serving multiple destinations scenario. Propositions of the proposed scheme are proved theoretically by closed-form solutions. Numerical results verify the effectiveness and correctness of the proposed scheme.

Tài liệu tham khảo

FCC: Spectrum Policy Task Force, Rep. ET Docket No. 02-135. 2002. FCC: Facilitating opportunities for flexible, efficient and reliable spectrum use employing cognitive radio technologies: notice of proposed rule making and order, FCC Document ET Docket No. 03-108. 2003. Mitola J: Cognitive radio, Licentiate proposal, KTH, Stockholm, Sweden. 1998. Mitola J: Software Radios: Wireless Architecture for the 21st Century. Wiley, New York; 2000. Demestichas P, Dimitrakopoulos G, Strassner J, Bourse D: Introducing reconfigurability and cognitive networks concepts in the wireless world. IEEE Veh Technol Mag 2006, 1(2):32-39. Letaief KB, Zhang W: Cooperative communications for cognitive radio networks. Proc IEEE 2009, 97(5):878-893. Guo Y, Kang G, Zhang N, Zhou W, Zhang P: Outage performance of relay-assisted cognitive-radio system under spectrum-sharing constraints. Electron Lett 2010, 46(2):182-184. 10.1049/el.2010.2159 Simeone O, Bar-Ness Y, Spagnolini U: Stable throughput of cognitive radios with and without relaying capability. IEEE Trans. Commun 2007, 55(12):2351-2360. Sadek AK, Han Z, Liu KJR: A distributed relay-assignment algorithm for cooperative communications in wireless networks. In Proc IEEE International Conference on Communications ICC'06. Volume 4. Istanbul, Turkey; 2006:1592-1597. Sadek AK, Han Z, Liu KJR: Distributed relay-assignment protocols for coverage expansion in cooperative wireless networks. IEEE Trans Mobile Comput 2010, 9(4):505-515. Wang B, Han Z, Liu KJR: Distributed relay selection and power control for multiuser cooperative communication networks using buyer/seller game. In Proc IEEE INFOCOM. Anchorage, Alaska; 2007:544-552. Sharma S, Shi Y, Hou YT, Sherali HD, Kompella S: Cooperative Communications in multi-hop wireless networks: joint fiow routing and relay node assignment. In IEEE INFOCOM 2010. San Diego, CA, USA; 2010:1-9. Shi Y, Sharma S, Hou YT, Sherali HD, Kompella S, Midkiff SF: Optimal relay assignment for cooperative communications. In Proc of ACM MobiHoc. Hongkong, China; 2008:3-12. Xie M, Zhang W, Wong K: A geometic approach to improve spectrum efficiency for cognitive relay networks. IEEE Trans Wirel Commun 2010, 9(1):268-281. Ng TC-Y, Yu W: Joint optimization of relay strategies and resource allocations in cooperative cellular networks. IEEE J Sel Areas Commun 2007, 25(2):328-339. Yeh EM, Berry RA: Throughput optimal control of cooperative relay networks. IEEE Trans Inf Theory 53(10):3827-3833. Zhang Q, Jia J, Zhang J: Cooperative relay to improve diversity in cognitive radio networks. IEEE Commun Mag 2009, 47(2):111-117. Jia J, Zhang J, Zhang Q: Cooperative Relay for cognitive radio networks. In IEEE INFOCOM 2009. Rio de Janeiro, Brazil, 19-25; 2009:2304-2312. Diestel R: Graph Theory. 3rd edition. Springer, Heidelberg; 2005. 3GPP TR 36.814 V9.0.0 3GPP TSG RAN (E-UTRA): Further advancements for E-UTRA physical layer aspects (Release 9). 2010.