Multiband chirp OCC-UWB system design for suppression of multiple narrowband interferences

To improve the coexistence between ultrawideband (UWB) technology-based wireless personal area networks and other narrowband systems and efficiently suppress the multiple narrowband interferences (NBIs) and the multiuser interference (MUI) in UWB systems, we propose a multiband orthogonal complementary code-based UWB (OCC-UWB) system design in this paper, which utilizes the simple time-frequency relationship of the chirp waveforms. The system design is implemented in 2 ways, named the equant multiband scheme and the nonequant multiband scheme. The 2 implementation schemes can improve the spectrum utilization of UWB systems and have different principles of NBI suppression. The equant scheme adopts the nonlinear chirp waveforms to suppress multiple NBIs in the sub-bands with NBIs. In contrast, the nonequant scheme adopts the spectrum elusion method based on the division of the frequency band to exclude the NBIs' frequency bands. Combining the chirp UWB pulse design with the orthogonal complementary code spread modulation, we finally present the multiband chirp OCC-UWB system to suppress the MUI and the multipath interference simultaneously. Simulation results and theoretical analysis show that the proposed multiband chirp OCC-UWB system improves the system performance efficiently in the conditions of multiple NBIs, MUI, and multipath interference and increases the data transmission rate and the spectrum utilization simultaneously.