HDCRAM Proof-of-Concept for Opportunistic Spectrum Access

This paper presents a proof-of-concept for opportunistic spectrum access. It particularly focuses on management requirements and how it impacts the design of cognitive radio equipments for secondary users in order to support this scenario. The proposed management architecture is called HDCRAM (Hierarchical and Distributed Cognitive Radio Architecture Management). This paper shows that depending on the behavior expected for different cognitive radio equipments, HDCRAM is deployed differently. It illustrates indeed that our approach can match any cognitive radio context. The demonstration is made with USRP platforms for the radio interface. The processing chain and the management are programmed in C++, using event programming so that the management is only activated when the cognitive radio environment changes. Otherwise, there is no overhead for a normal radio operation.