  We present a new method for time delay estimation using band limited
frequency domain data representing the port responses of interconnect
structures. The approach is based on the recently developed by the authors
spectrally accurate method for causality characterization that employs
SVD-based causal Fourier continuations. The time delay extraction is
constructed by incorporating a linearly varying phase factor to the system of
equations that determines Fourier coefficients. The method is capable of
determining time delay using data affected by noise or approximation errors
that come from measurements or numerical simulations. It can also be employed
when only a limited number of frequency responses is available. The technique
can be extended to multi-port and mixed mode networks. Several analytical and
simulated examples are used to demonstrate the accuracy and strength of the
proposed technique.
