| A new paradigm for wireless communications which is aimed at enabling a more efficient use of the spectrum has recently come to the fore. In this new paradigm for the industry, unlicensed (or secondary) users are equipped with intelligent devices that are capable to utilize licensed bands provided that the licensed (or primary) users are absent or the quality of their communication is are kept at satisfactory level. Given that this requires the ability of radio devices to reconfigure in response to changing operating conditions, this paradigm for wireless communication is typically referred to as a "cognitive radio network (CRN)". Though appealing in theory, this paradigm faces significant technical and regulatory challenges. This thesis focuses on providing a novel cross-level framework for the design of efficient and effective spectrum/radio resource management schemes for the CRN.;This thesis studies two broad categories of CRN: (1) The network with secondary and primary networks operating at the same time; (2) The network with secondary networks only. In physical level, we use communication theory to design the media access protocols; in system and algorithmic levels, we use game theory and optimization theory to model the resource sharing behavior and the interaction of different entities in the network; in regulatory level, we use economic theory to interpret, and validate the lower-level designs. Our comprehensive cross-level design approach results in a set of distributed and convergent algorithms that achieve efficient spectrum utilization. |
