Estimation of time delay in the presence of source or receiver motion

Signals, received at two (or more) locations, and originating from a remote acoustic point source, exhibit time delay(s) that are useful for estimating source location or receiver geometries. Consequently, numerous procedures have been proposed for passive time‐delay estimation in such cases. Past investigations apply, however, only when source and receiver motion is negligible. This paper extends previous results for maximum‐likelihood (ML) estimation of time delay to the situation where the source, or the receivers, or both are in motion. It is shown that in the simplest case with two receivers, one of the signals must be appropriately time scaled prior to computing a generalized cross correlation of the received signals.