Cognitive Radio Systems via Game Theory

Radio regulatory bodies are recently recognizing that rigid spectrum assignment granting exclusive use to licensed services is highly inefficient. A more efficient way to utilize the scarce spectrum resources is with a dynamic spectrum access, depending on the real spectrum usage and traffic demands. The concept of cognitive radio has recently received great attention from the research community as a promising paradigm to achieve efficient use of the frequency resource by allowing the coexistence of licensed (primary) and unlicensed (secondary) users in the same bandwidth.
    We consider underlay/interweave multi-antenna networks, where primary users establish proper null and/or soft shaping constraints on the transmit covariance matrix of secondary users, so that the interference generated by secondary users is confined within the interference-temperature limits. The secondary users compete then for the resource allocation, which can be formally modeled with game theory to obtain a completely decentralized approach.