Use of a local regularity analysis by a wavelet analysis for glitches detection
Résumé
We present a method based on local regularity analysis to detect glitch signatures in an interferometric signal. The regularity is given by the local value of the Holder exponent. This exponent can be derived using a Holderian analysis with a wavelet coefficients modulus calculation along wavelet transform modulus maxima lines (so called WTMML) in suitably selected regions of the time-scale half-plane. Glitches that are considered as a discontinuity on the signal show Holder exponent lower than a fixed threshold defined for a continuous signal (around -1). The method has been tested using computed histograms simulations derived from "HERSCHEL / SPIRE" theoretical signals. Statistics show that the optimization of the detection parameters should take into account variables such as sampling rate, signal to noise ratio but is almost independent of the glitch amplitude.