An ML Timing Estimator in UWB Communication Systems

The problem of estimating the timing of ultra-wide band signal is considered in the letter. We develop a maximum likelihood timing estimation algorithm for binary PAM DS-UWB systems. The derivation of the proposed algorithm is based on the known training sequence and AWGN channel. The Cramer-Rao Bound (CRB) for the ML timing estimator is presented as a performance benchmark. It is found via numerical results that the ML timing estimator on AWGN channels achieves the CRB when the values of E sub(b)/N sub(0) for the observation bits N sub(b)=50 are sufficiently high. Finally, the performance of the proposed ML estimator is evaluated on actual channels with intersymbol interference such as an I II UWB indoor multipath channel model.