Spatial distributed dynamic spectrum access

The spatial aspect of distributed dynamic spectrum access (DSA) in a wireless ad hoc network is usually overlooked in the literature. By using tools from stochastic geometry, we analytically characterized the spatial distribution of users and subsequent interference in the network. Provided with multiple channels, users in the network interact in the sense that the channel selections they make affects co-channel interference they impose on each other, forming a new and general scope of DSA. The study of strategic interactions among users sharing the spectrum are facilitated by a game-theoretic formulation, where the strategy at the Nash equilibrium and the corresponding performance are analytically obtained. Based on the model, we consider further the case when users have multi-channel sensing capability. Access strategies incorporating channel availability information are developed and the corresponding performance is analyzed. Finally, we show that channel (frequency) diversity can be exploited that enables effective design when users are capable of performing concurrent communications over multiple channels. The results of our work provides insights to and facilitates the design of medium access strategies for DSA.