Contents
Which is the wavenumber for the Morlet transform?
For the Morlet wavelet transform, where the mother wavelet is: we must first choose the wavenumber w0, which gives the number of oscillations within the wavelet itself. One condition of the wavelet transform is that the average of the wavelet itself must be zero.
Who is the creator of the Morlet wavelet?
A famous continuous wavelet has been built by Jean Morlet with the objective of creating a tool like a constant-Q filter bank ( Grossmann and Morlet 1984; Strang and Nguyen 1996). A representation of the Morlet wavelet Eq.
Why do we use the Morlet wavelet in nino3?
For decomposing the NINO3 SST data, we chose the Morlet wavelet because: it is commonly used, it’s simple, it looks like a wave. There are an infinite number of other mother wavelets that could be chosen (see Farge 1992 for examples).
How is the wavelet transform used in science?
The wavelet transform is a method to decompose a real signal f into a set of elementary waveforms that provide a way to analyze the signal by examining the wavelet coefficients (Graps 1995).
How to calculate Morlet transformation of a time series?
View source: R/WaveletTransform.R It computes the Morlet wavelet transformation of a given time series, subject to criteria concerning: the time and frequency resolution, an (optional) lower and/or upper Fourier period.
Why do we use the Morlet wavelet in nino3 SST?
The first thing to consider is the shape of the wavelet. For decomposing the NINO3 SST data, we chose the Morlet wavelet because: it is commonly used, it’s simple, it looks like a wave. There are an infinite number of other mother wavelets that could be chosen (see Farge 1992 for examples).
How to normalize daughter wavelet in real space?
Normalize the daughter wavelet by dividing by the square-root of the total wavelet variance (the total of (Psi)2should then be one, thus preserving the variance of the time series); Multiply by the FT of your time series; Using Eqn. 3.2, inverse transform back to real space; Make a contour plot.