WLC05-4: Game-theoretic Distributed Spectrum Sharing for Wireless Cognitive Networks with Heterogeneous QoS

Ubiquitous wireless networking calls for efficient dynamic spectrum allocation (DSA) among heterogeneous users with diverse transmission types and bandwidth demands. To meet user-specific quality-of-service (QoS) requirements, the power and spectrum allocated to each user should lie inside a bounded region in order to be meaningful for the targeted application. Most existing DSA methods aim at enhancing the total system utility. As such, spectrum wastage may arise when the system-wise optimal allocation falls outside the desired region for QoS provisioning. The goal of this paper is to develop QoS-aware distributed DSA schemes using the game-theoretic approach. We derive DSA solutions that respect QoS and avoid naively boosting or sacrificing some users' utilities to maximize the network spectrum utilization. Specifically, we propose two game-theoretic DSA techniques: one resorts to proper scaling of the transmission power according to each user's useful utility range, and the other embeds the QoS factor into the utility function used for dynamic gaming. In addition, we introduce two new metrics to evaluate DSA schemes from a practical QoS perspective, namely "system useful utility" and "fraction of QoS satisfied users." Simulations confirm that the proposed DSA techniques outperform existing QoS-blind game models in terms of spectrum sharing efficiency in heterogeneous networks.