A Novel Active Spectrum Sensing Scheme for Cognitive MB-OFDM UWB Radio

Spectrum awareness is the key technique for Cognitive Radio (CR). A special spectrum sensing scheme is necessary for Cognitive UWB radio (CUWB) because of its lower radio power and ultra wide bandwidth. Although CUWB transmitter and receiver could respectively detect the spectrum holes, they couldn´t communicate with each other probably if they are out of the communication range or there isn´t common usable spectrum segment for them. No sensing technique deals with these problems properly. In this paper a novel active spectrum sensing scheme for cognitive MB-OFDM UWB radio is presented to settle the above problems. The scheme takes full advantage of UWB and finds usable channels directly for CUWB transmitter and receiver through sending beacon signals and acknowledgement signals. This active spectrum sensing scheme is totally different from existing sensing methods and has its own advantages.