Acoustic echo detection and arrival-time estimation using spectral tail energy
Phillip L. Ainsleigh · The Journal of the Acoustical Society of America · 2001
An algorithm is introduced for detecting signal and echo onsets and estimating their arrival times in multipath acoustic data. The algorithm accommodates superimposed narrow-band signals with continuous onsets, unknown envelopes, and arrival-time separations of less than one cycle at the dominant tonal frequency. It does not require the multipath components to be shifted and weighted replicas of each other or of a template signal. The separation of closely spaced signals is enabled by applying a prefilter that isolates spectral “tail” energy in which the onsets are discernible, and by operating on the filtered data using a matched-subspace detector that is conditioned on previously detected onsets. This algorithm has particular value for laboratory measurements, as it utilizes the high signal-to-noise ratios available in a laboratory to solve a previously intractable detection and estimation problem.