Scrambler design to reduce power spectral density of UWB signals in IEEE 802.15.3a

Ultra wide-band (UWB) radio uses base-band pulses of very short duration, thereby spreading the energy of radio signal very thinly over gigahertz. Power spectral density (PSD) of UWB signals consists of continuous component and discrete component. Generally speaking, the discrete component contributes more to the PSD than the continuous component, thus presents greater interference to narrow-band wireless systems. In 2002, the FCC approved commercial deployment of UWB systems. In order to ensure negligible interference to other narrow-band wireless systems, the FCC has specified emission limits for UWB applications. UWB is now under consideration as an alternative physical layer technology for wireless PAN in IEEE 802.15.3a. However, little study has been reported on how to contain the PSD of UWB signals in IEEE 802.15.3a. This paper presents base-band data whitening schemes to reduce the PSD of UWB signals in IEEE 802.15.3a.