Efficient Spectrum Usage for Wireless Communications

Radio spectrum, as the physical support for wireless communication, both for fixed applications and especially for mobile broadband, is becoming an extremely strategic, valued, and demanded resource. [...]technologies and techniques enabling a more flexible access for service providers and clients and a more efficient and effective usage are needed. Cognitive radio takes a more active approach, making the devices responsible of efficient spectrum utilization by sensing spectrum usage and adjusting transmission parameters to accommodate communications in unused resources. [...]regulatory frameworks like the recent Licensed Shared Access (LSA) may play a crucial role in helping mobile networks operators to make a more efficient usage of the scarce bandwidth resources.