Commercial X-band marine radar which original used for ship navigation purpose is now developed as a remote sensing technique for ocean wave and current measurements. This paper presents the coastal wave and current distribution extracted from marine radar image sequences. The spatial current results from radar are verified by in-situ current data measured by GPS drifting buoy. The result shows...

Operator fractional Brownian motion (OFBM) is the natural vector-valued extension of the univariate fractional Brownian motion. Instead of a scalar parameter, the law of an OFBM scales according to a Hurst matrix that affects every component of the process. In this paper, we develop the wavelet analysis of OFBM, as well as a new estimator for the Hurst matrix of bivariate OFBM. For OFBM, the un...

Spectrum sensing techniques are envisaged to solve the problems in wireless networks resulting from the limited available spectrum and the inefficiency in the spectrum usage. In this paper various Spectrum Sensing Techniques like Energy Detection, Matched Filter, Cyclo-stationary Detection, Wavelet Detection are compared. The best one is evaluated for its performance. Then Cooperative Spectrum ...

This paper presents the Fourier and wavelet characterization of vibratio...

This paper concerns the issue of wavelet analysis of signals by continuous and discrete wavelet transforms (CWT – Continous Wavelet Transform, DWT – Discrete Wavelet Transform). The main goal of our work was to develop a program which, through the CWT and the DWT analyses, would obtain graph of time-scale changes and would transform it into the spectrum, that is a graph of frequency changes. In...

Using available signal (i.e., spectral and time-frequency) analysis methods, it can be difficult to detect neural oscillations because of their continuously changing properties (i.e., nonstationarities) and the noise in which they are embedded. Here, we introduce fractally scaled envelope modulation (FSEM) estimation which is sensitive specifically to the changing properties of oscillatory acti...

In the present study using the wavelet theory (WT) and later the nonlinear spectrum response of the acceleration (NSRA) resulted in estimating a strong earthquake record for the structure to a degree of freedom. WT was used in order to estimate the acceleration of earthquake mapping with equal sampling method (WTESM). Therefore, at first, the acceleration recorded in an earthquake using WTESM w...

BACKGROUND Compared to the waveform or spectrum analysis of event-related potentials (ERPs), time-frequency representation (TFR) has the advantage of revealing the ERPs time and frequency domain information simultaneously. As the human brain could be modeled as a complicated nonlinear system, it is interesting from the view of psychological knowledge to study the performance of the nonlinear an...

This study examined whether interpersonal synchrony could be extracted using spectrum analysis (i.e., wavelet transform) in an unstructured conversation. Sixty-two female undergraduates were randomly paired and they engaged in a 6-min unstructured conversation. Interpersonal synchrony was evaluated by calculating the cross-wavelet coherence of the time-series movement data, extracted using a vi...

This article defines and studies a new class of non-stationary random processes constructed from discrete non-decimated wavelets which generalizes the Cramér (Fourier) representation of stationary time series. We define an evolutionary wavelet spectrum (EWS) which quantifies how process power varies locally over time and scale. We show how the EWS may be rigorously estimated by a smoothed wavel...