A computationally inexpensive algorithm suitable for fast, high-resolution
estimation of time delays and Doppler shifts (which are necessary for targe
t ranging and tracking) between narrowband signals is presented. The algori
thm uses a modulated Lagrange interpolation filter and an LMS-type algorith
m. The problem of delay and Doppler estimation is reduced to a linear regre
ssion problem. Convergence and performance analysis of the method is studie
d both analytically and through simulation. It is demonstrated that the met
hod provides more (or as) efficient estimates than modulated sine interpola
tion or the corresponding unmodulated algorithms for a variety of condition
s.