Estimation and analysis of signal arrival time for UWB systems

In this paper, an improved MUSIC algorithm is presented for estimation of signal arrival time in impulse radio UWB systems. An accurate estimate of signal arrival time is considered essential in time-based wireless and indoor location systems. The fine resolution of UWB signals provides potentially accurate ranging for indoor geolocation. However, the ambiguity caused by the irresolvable first arrival path may still yield an error in determining the true signal arrival time. To use the improved MUSIC technique in estimation of the shortest signal arrival time for UWB radio link, an experimental criterion of path resolvability is defined. For a two-multipath case, simulations are conducted. The results show that the improved MUSIC algorithm achieves better probability of multipath resolvability, and smaller variance of estimation errors than other MUSIC methods.