Waveform designs for cognitive radio and dynamic spectrum access applications

Cognitive radio and dynamic spectrum access systems are effective ways of using radio spectrum which is a scarce source. Cognitive radio applications changed the paradigm for the wireless communications systems in the past decades. Besides that, different communications systems and wireless communications channels require different waveform designs and radio access technologies. In this study, a general design and evaluation procedure for the new waveform techniques are presented based on cognitive radio and dynamic spectrum access requirements. Radio access technology researches for the future-generation cellular systems and cognitive radio systems intersect to each other. Therefore, some of the future waveform designs and related modifications are analyzed under the cognitive radio perspective. Several waveforms which have various trade-off situations are discussed from a general perspective and an adaptivity/flexibility perspective.