Hao Yue (Associate Professor San Francisco State University)
Innovative use of wireless devices such as smartphones in various mobile applications has exacerbated the congestion over cellular spectrum. On the other hand, many licensed spectrum blocks are left unused. Although cognitive radios (CR) technology has emerged as an enabler for unlicensed users to opportunistically access the unused licensed spectrum, there is still a lack of practical and flexible networks in which not only the unlicensed users with CR devices but also those with non-CR capable devices can benefit from the opportunistic access to the unused spectrum.
In this talk, a novel network architecture, called the Cognitive Capacity Harvesting network (CCH), is introduced. In CCH, a collection of CR Routers are introduced to facilitate the accessing of unlicensed users. In view of the importance of CR Routers’ locations on the performance of the CCH, the optimal placement strategy for the CR Routers is studied. A cost minimization problem is mathematically formulated. Considering the NP-hardness of this problem, a framework of heuristic algorithms are designed to compute the near-optimal solutions.