Secondary spectrum access networks
Xuemin Hong, Cheng‐Xiang Wang, Hsiao‐Hwa Chen, Ke Zhang · IEEE Vehicular Technology Magazine · 2009
The radio spectrum is a precious resource that underpins various wireless services. It is traditionally regulated by a fixed frequency assignment policy, which allocates frequency bands to license holders for exclusive use. Dynamic spectrum access has been proposed as a promising approach to improve spectrum utilization by allowing new wireless systems to dynamically access or share the licensed band on a negotiated or an opportunistic basis.