OpenAirInterface and ExpressMIMO2 for Spectrally Agile Communication

This chapter provides an overview of the OpenAirInterface (OAI) both in terms of its hardware and software elements and its usage in cognitive wireless networking applications based on long term evolution (LTE) technology. In particular, we show a design of a cognitive radio systems in the LTE framework that enables the deployment of cognitive radio in licensed bands, with no hardware modification and only small software changes in some specific frames for the secondary system.Moreover, we show the challenges and some solutions of operation of LTE in TV white spaces.