Date Added: Jun 2010
Dynamic Spectrum Access (DSA) is proposed to deal with the growing shortage of available leased spectrum for wireless communication. The authors investigate a subset of DSA referred to as Dynamic Spectrum Leasing (DSL). At its core, DSL allows spectrum lease holders and cognitive radios to cooperate in an effort to leverage spatial diversity to improve channel utilization for both parties. In this paper, cognitive radios offer their services as an intermediate relay node in an effort to improve throughput of primary users utilizing a 802.11-based channel access mechanism. In return, the cognitive radio 'Piggy-backs' some of its own data while acting as a relay.