WLC18-6: Modified GML Algorithm for Estimation of Signal Arrival Time in UWB Systems

In this paper, estimation of the signal arrival time based on the generalized maximum-likelihood (GML) algorithm for multi-band orthogonal frequency division multiplexing (MB- OFDM) ultra wide-band (UWB) systems is presented. The estimation algorithm uses the ranging reference portion of the preamble signal in the MB-OFDM UWB system for estimation of the time of arrival (TOA). To mitigate the effects from dense multipath interference and to reduce the computational complexity of the estimation algorithm, a modified GML algorithm is proposed. The problems of threshold settings in the modified GML algorithm, based upon the minimum root mean square error (RMSE) criteria, are discussed. Comparing with the conventional cross-correlation method and the original GML approach, the computer simulation results show that the proposed modified GML algorithm achieves better performance in estimation of the signal arrival time.