A Novel Frequency-band Coded Orthogonal UWB Chirp Pulse Design for Cognitive NBI Suppression

In this paper, a novel frequency-band coded orthogonal UWB pulse design method based on Chirp signal is presented. The new approach uses the chirp signals located at different frequency-bands to synthesize the orthogonal pulses by coding with Pseudo Noise sequence in frequency domain. The auto-correlation and cross-correlation property of the proposed chirp pulses are better than those of other conventional pulses. Furthermore, the new method also improves the efficiency of the instantaneous spectrum and energy of the transmitting UWB signal. In addition, by the aid of cognitive radio technology to adjust the chirp envelope and the frequency-sweeping range of each chirp subpulse , it can guarantee the transmitting UWB signal to be matched with the different UWB spectrum regulations and coexistence, interference avoidance with other traditional narrow band systems. And simulation result showed that the proposed pulse could reduce the effect of NBI on UWB system with litter complexity.