Super-resolution time delay estimation in multipath environments using normalized cross spectrum

Conventional time delay estimation approaches usually only deal with direct signal model, they are not suitable for multipath environments. And most approaches can´t estimate integral and fractional delay at once. In order to overcome these defects, in this paper, we propose a super-resolution time delay estimation method that takes advantage of normalized cross spectrum of observed signals for passive systems. The CRB of time delay estimation is be given in multipath environments. Simulation results confirm that proposed time delay estimator can estimate integral and fractional time delay at once, and provides a super-resolution performance.