The Matched Reassigned Cross-Spectrogram for Phase Estimation

Abstract

In this paper, the matched reassigned spectrogram is expanded into a novel matched phase reassignment (MPR) method based on the reassigned cross-spectrogram. It is shown that for two phase synchronized oscillating transient signals, the method gives perfect time-frequency (TF) localization. The MPR is thereby a TF local measure of phase synchronization and can also be used to measure phase difference between short transient signals. We explore the technique to measure the phase difference, and compare to commonly used phase estimators, for different types of disturbances. We also investigate the methods ability to classify phase synchronized and non-synchronized signals. Simulations show that the MPR method outperforms the state-of-the-art methods. An illustrative example of phase difference estimates of the electrical signals measured from the brain is included.