ABSTRACT
Contents 17.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 380
17.1.1 Why Focus on OFDM-Based Cognitive Radio? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 380 17.1.2 What Is Specific about DRA in OFDMA? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 381 17.1.3 Why Game Theory? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 382
17.2 Overview of Game-Theoretic OFDMA Resource Allocation . . . . . . . . . . . . . . . . . . . . . . . . . . . 382 17.2.1 Cooperative Solutions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 383 17.2.2 Noncooperative Solutions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 383
17.3 Cognitive DRA in OFDMA Based on Resource Taxation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 384 17.3.1 Efficiency versus Rationality: The Tragedy of Commons . . . . . . . . . . . . . . . . . . . . . . 384 17.3.2 The Scenery of a Cognitive Radios Network: The Players . . . . . . . . . . . . . . . . . . . . . 385 17.3.3 Considerations on the Strategies of the CRs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 385 17.3.4 Considerations on Payoff Functions for the DSA Game in OFDMA . . . . . . . . . 386 17.3.5 Experimental Results. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 389
17.4 OFDM Adaptive Transmission as a Game . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 392 17.4.1 The Idea of a Game against the Nature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 393
17.4.1.1 Strategies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 393 17.4.1.2 Payoffs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 394
17.4.2 Experimental Results. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 395 17.5 Concluding Remarks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 397
17.5.1 Open Issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 397 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 397
The orthogonal frequency division multiple access (OFDMA) is considered as one of the most promising techniques for multiuser high data-rate wireless communication. One can envision future OFDMA-based cognitive radio (CR) systems, in which the unlicensed users can access the spectrum in an opportunistic manner while applying OFDMA as a flexible air interface. Noticeable worldwide interest in OFDMA-based CR has motivated research on efficient and opportunistic spectrum access and dynamic resource allocation (DRA) for this technology. This research focuses on finding spectrally efficient DRA algorithms, which also take fairness of the resource distribution into account. Noteworthily, game theory provides good tools to approach the problems of efficient, yet fair DRA. The main purpose of using them in the CR framework is to model strategic interactions among the network users considered as players who access and make the best use of the available spectrum resources in a cognitive and opportunistic manner.
