Improved transient oscillation detection with multiwavelets

Abstract

Multiwavelets have recently been used for analysis of transient oscillations. Here we use them for transient oscillation detection by incorporating them into two existing Morlet-based self-normalizing detectors, one that operates on a single time series and another on two correlated time series. The Morlet-based detectors are effective in detecting weak, transient oscillations, especially in strong clutter where FFT based methods fail. Simulated receiver operating curves reveal that the new multiwavelet detectors show marked improvement when applied to complex, transient oscillations in white Gaussian noise and 60 dB clutter. At 0.1% false alarm rate for a (signal on) signal to noise ratio of 0.25, detection rates are: 95.5% and 99.6% for the single and dual time series detectors, respectively. These compare to 75% and 95.5% for the Morlet wavelet detectors.