2018/09/10 by W.J. Szajnowski, Szajnowski, W. J.
Earth and Planetary Sciences · Engineering · #Advanced Fiber Optic Sensors #FOS: Electrical engineering #Optical Coherence Tomography Applications #Seismic Waves and Analysis #Signal Processing (eess.SP) #electronic engineering #information engineering
paper · pdf · doi:10.48550/arxiv.1809.03192
openalex publication_date 2018/09/10 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
It is shown that multiple representations (such as replicas or Hilbert transforms) of a random waveform can interfere constructively to form a compact pattern, akin to a wave packet, when the representations are created in synchrony with zero crossings of the waveform. A function of such 'engineered' zero-crossing interferograms can exhibit time-delay resolution superior to that associated with a conventional correlation function, especially for waveforms with slowly-decaying power spectra. A phenomenon of local slew rate at zero crossings is exploited to substantially reduce the Cramér-Rao bound on time-delay estimators. A system, based on a concept of elapsed time, is proposed to determine zero-crossing interferograms in real time.