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We present an analytical model that enables the evaluation of opportunistic spectrum orthogonal frequency division multiple-access (OS-OFDMA) networks using metrics such as blocking probability or, most importantly, throughput. The core feature of the model, based on a discrete-time Markov chain, is the consideration of different channel and subchannel allocation strategies under different primary and secondary user types, traffic, and priority levels. The analytical model also assesses the impact of different spectrum sensing strategies on the throughput of OS-OFDMA network. In addition, we consider studies of cochannel interference. The analysis is applied to the IEEE 802.22 standard to evaluate the impact of the two-stage spectrum sensing strategy and the varying temporal activity of wireless microphones on the system throughput. In addition to the analytical model, we present a set of comprehensive simulation results using NS-2 related to the delay performance of the OS-OFDMA system considered. Our study suggests that OS-OFDMA with subchannel notching and channel bonding could provide almost ten times higher throughput compared with a design without these options when the activity and density of wireless microphones are very high. Furthermore, we confirm that OS-OFDMA implementation without subchannel notching, which is used in the IEEE 802.22, can support the real-time and non-real-time quality of service classes, provided that the temporal activity of wireless microphones is moderate (with sparse wireless microphone distribution, with light urban population density and short duty cycles). Finally, the two-stage spectrum sensing option improves the OS-OFDMA throughput, provided that the length of spectrum sensing at every stage is optimized using our model. [ABSTRACT FROM PUBLISHER]

IEEE 802.22 is the first cognitive-radio-based wireless communication standard. To manage resource sharing, IEEE 802.22 designs an interbase station (inter-BS) coexistence mechanism enabling distributed competing BSs to coexist effectively. In this IEEE 802.22 mechanism, BSs could be considered as players optimizing their own performance in a self-organizing way. Therefore, it is suitable to apply game theory to model the convergence of self-organizing behaviors. An operating point where no BS can unilaterally increase its performance describes an outcome of the inter-BS coexistence mechanism; this steady-state operating point is the well-known Nash equilibrium in game theory. In this paper, an IEEE 802.22 inter-BS coexistence issue is investigated from a game-theoretical perspective. As the IEEE 802.22 standard defines the inter-BS coexistence mechanism, we design a resource-transaction algorithm to realize IEEE 802.22 dynamic resource renting and offering (DRRO) and adaptive on-demand channel contention (AODCC) operation. We also use game theory to model and analyze the proposed algorithm. In game analysis, we first study a two-player game through a graphical method to gain insights for the solution. Afterward, we investigate a general n-player game and derive the Nash equilibrium where the resource allocation is uniquely determined. The resource allocation is efficient, as the overall system performance is maximized (allocative efficiency), and no BS can further improve its performance without impairing others (Pareto optimality). The resource allocation also achieves max-min fairness and proportional fairness. Furthermore, the proposed algorithm ensures all resource acquirers' participation without resource loss (individual rationality). It also guarantees revenue maximization of the resource provider. [ABSTRACT FROM AUTHOR]