Time delay estimation in the presence of relative motion

Time delays between signals observed at one or more pair of receivers and originating from a remote acoustic point source, are useful for estimating source or receiver location. 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 is in motion relative to one or both receivers. It is shown that ideally one of the received signals must be appropriately time scaled prior to computing a generalized cross correlation of the received signals.