Analysis on interference of DS-UWB signal to narrowband systems

The power of ultra-wideband (UWB) signals has an extremely large frequency bandwidth which is a potential interference to narrow band systems. So UWB systems must obey the rules of frequency management of FCC when share frequency resources with traditional narrowband systems. It´s presented the analysis of power spectral density (PSD) of direct sequence code UWB (DS-UWB) signals and some key factors of interference power of DS-UWB signals. It´s studied that the relationship between envelop of DS-UWB PSD and energy spectral density (ESD) of pulse waveform and that among continuous and disperse components of PSD, modulated sequences and pulse repetition frequency (PRF). It´s shown that some pseudo-random codes with suitable properties and parameters can reduce the interference power of DS-UWB signals to narrowband systems. Simulations have been done to prove it in this paper