Cramer-Rao bound for channel parameters in ultra-wide band based system

This work focuses on channel estimation in standard ultra-wide band (UWB) based system. We consider impulse radio scheme relying on a binary pulse position modulation as well as on a spread-spectrum time-hopping multiple access. We address the closed-form expressions of the (resp. modified) Cramer-Rao bound for the multipath channel parameters in data-aided (resp. nondata-aided) context. The derivations have been developed by assuming the multiple-access interference as an additive white Gaussian noise. Conversely the overlapping between signal echoes has been taken into account. Finally simplifications have been done by averaging the Fisher information matrix over the time-hopping random sequence as well as over the symbol random sequence.