Horizontal Synchrosqueezing Transform: Algorithm and Applications
Xiaotong Tu, Zhoujie He, Yue Hu, Saqlain Abbas, Fucai Li
Abstract
Advancements in the synchrosqueezing transform as a postprocessing time-frequency method have received considerable attention in the past few decades for the analysis of nonstationary signals. Many studies have focused on improving the accuracy of the estimated instantaneous frequency (IF). In some fields, the IF spectra of signals exhibit fast varying behavior or even some times parallel to the frequency axis. Thus, a majority of the existing methods may fail to adequately handle the transient signals such as guided waves and vibration waves. To address this problem, a new method called the horizontal synchrosqueezing transform (HST) is introduced in the present research study. By applying a local estimation of the group delay (GD), the proposed technique can yield a compact time-frequency representation for a transient signal while retaining its invertibility. For the purpose of validation, the proposed approach is implemented in both synthetic and real signals. The results are observed in a convincing manner in terms of the smaller value of the Rényi entropy and better reconstruction accuracy. The HST is supposed to be a reliable and accurate method for the analysis of transient signals with extensive usefulness.