Cooperative game-theoretic modeling for spectrum sensing in cognitive radios

This paper addresses the problem of spectrum sharing in cognitive radios where secondary users cooperatively sense the spectrum for identifying and accessing unoccupied spectrum bands. It is shown that this scenario can be modeled as a cooperative game to allocate spectrum resources fairly to each user. Users form coalitions to jointly sense and share the spectrum. The worth of each user is calculated according to the work done for the coalition in terms of the information obtained about primary user activity from sensing the spectrum. The resulting games are balanced, thereby ensuring non-empty cores for allocating resources to users. The games are also convex, thus enabling one-point solution concepts such as the Shapley value, tau value and nucleolus to lie within the core to provide stability. The concept and results are illustrated using a simple toy example.