Cognitive UWB-OFDM: Combining Ultrawideband with Opportunistic Spectrum Usage

In a continuously expanding wireless world, the number of radio systems increases every day, and efficient spectrum usage becomes a more significant requirement. Ultrawideband (UWB) and cognitive radio are two recent and exciting technologies that offer a new approach to the spectrum usage. The main objective of this paper is to combine these two technologies. The strength of orthogonal frequency division multiplexing (OFDM) based UWB in co-existing with licensed systems is investigated. The opportunity concept is defined, and the requirements of the opportunistic spectrum usage are explained. It is proposed to take the UWB-OFDM from the current underlay implementation, and evolve it to a combined underlay and opportunistic spectrum usage technology, leading to cognitive UWB-OFDM. This way, we aim at making UWB more competitive in the wireless market with extended range, higher capacity, better performance, and a wide variety of applications.