Characterization of inter-pulse interference and fading for ultra-wideband systems

A statistical characterization is presented of the impact of the ultra-wideband (UWB) multipath channel on impulse radio and spread-spectrum UWB systems. For this purpose, the correlator output statistics are studied, since correlators are the typical first processing step in the frontends of coherent and noncoherent receivers. The analysis is based on the second and forth-order moments of the channel impulse response. It also includes a prototype pulse shape that represents the bandwidth of the received pulse and all linear system components including antenna effects. Complex-equivalent baseband representations of UWB pulses are assumed, which makes the analysis suitable for investigating bandpass-type UWB systems as defined in various IEEE standards. The analytical results are validated through the analysis of measured UWB channels.