Cognitive radio communications and networks : principles and practice When radio meets software Radio frequency spectrum and regulation Digital communication fundamentals for cognitive radio Spectrum sensing and identification Spectrum access and sharing Agile transmission techniques Reconfiguration adaptation and optimization Fundamentals of communication networks Cognitive radio network architectures User ciiperative communications Information theoretical limits on cognitive radio networks Cross layer optimization for multihop cognitive radio networks Defining cognitive radio Cognitive fadio for broadband wireless access in TV bands : the IEEE 802.22 standards Cognitive radio network security Public safety and cognitive radio Auction based spectrum markets in cognitive radio networks GNU radio for cognitive radio experimentation Cognitive radio platforms and testbeds Cognitive radio evolution