Dynamic spectrum sharing for future wireless communications

Thesis

The spectrum has become one of the most important and scarce resources for future wireless communications. However, the current static spectrum policy cannot meet the increasing demands for spectrum access. To improve spectrum efficiency, dynamic spectrum access (DSA) attempts to allocate the spectrum to users in an intelligent manner. Cognitive radio (CR) is an enabling technology for DSA, and can maximize spectrum utilization by introducing unlicensed or secondary users (SUs) to the primary system. The key component of DSA is dynamic spectrum sharing (DSS), which is responsible for providing efficient and fair spectrum allocation or scheduling solutions among licensed or primary users (PUs) and SUs. This thesis focuses on the design of efficient DSS schemes for the future wireless communication networks.

Firstly, based on the coordinated DSS model, this thesis proposes a heterogeneous-prioritized spectrum sharing policy for coordinated dynamic spectrum access networks. Secondly, based on the uncoordinated DSS model, a novel partial spectrum sharing strategy and the cross-layer optimization method have been proposed to achieve efficient spectrum sharing between two licensed networks. Then, a hybrid strategy which combines the overlay and underlay schemes is proposed under uncoordinated DSS model. The proposed analytical methods can provide efficient and accurate modeling to predict the behaviors of the PUs and SUs in DSS systems. This thesis presents the performance prediction of the proposed novel DSS schemes that achieve efficient spectrum sharing for coordinated and uncoordinated future wireless networks.

Authors: Jiang, X

• Publication date: 2013-04-24
• Type of award: DPhil
• Level of award: Doctoral
• Awarding institution: Oxford University, UK
• Language: English
• Keywords: wireless communications; performance analysis; dynamic spectrum access; Markov chain
• Subjects: Communications engineering (optical,microwave and radio)