Tapering out a waveform.

Hello Guys,

Is there a way I can taper off this waveform such that it gently slopes out to zero at the end? Perhaps adding synthetic points? Such that it will not greatly affect the FFT of the pulse? Below is a clip of some sample data

I also have more points that follow this pulse but the wave signal contains many reflections and should not be used in FFT for that reason. (maybe these other points are needed to be taper out.

Thanks!

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Answer 1

[Wayne King]

The classic answer to this problem is to multiply the signal by a "window" such as the Hamming window, so if X is your signal.

 Y = X.*hamming(length(X));

You may have to transpose one of the vectors, hamming() returns a column vector.

However, the waveform you show above does not change much with tapering by a window.