A decision-feedback autocorrelation receiver for pulsed ultra-wideband systems

Efficient capture of multipath energy is one of the most significant problems of pulse-based ultra-wideband (UWB) systems in non-line-of-sight propagation environments. The traditional RAKE receiver could practically capture only a small fraction of the received signal energy because tracking and estimation of a large number of multipath components are very challenging. The transmitted-reference schemes could effectively collect energy in all received multipath components, but the energy efficiency and data rate drop significantly because of the required pilots. In addition, the use of a noisy template waveform may significantly degrade the receiver performance. In this paper, we propose a decision-feedback autocorrelation receiver for pulsed UWB systems. The decision-feedback structure provides an effective method that enables efficient capture of energy in all received multipath components and could eliminate the noise in the self-derived template waveform. A performance comparison between a RAKE receiver, a transmitted-reference scheme, and the proposed scheme is provided.