Experiments

For study the FFT of periodic and EEG signal program is written in the matlab by using the signal processing function FFT. The FFT of periodic signal shows the different for the sine, square, triangular, swatooth signals. FFT of EEG signal shows that the frequency components
present in that signal.

The algorithm of this periodic signal program is given bellow.

Algorithm
For the periodic signal
i) Create a periodic signal using signal processing functions.
ii) Mention the sampling frequency
iii) Give the amplitude and frequency of the periodic signal
iv) Pot that signal
v) Take the FFT of the input signal
vi) Plot the half of the sampling frequency components for the x axis.
vii) Plot the FFT of the signal frequency verses amplitude.

For the EEG signal

i) First read EEG input data from the .xls file.
ii) Give the sampling frequency given when recording the EEG signal.
iii) Plot the EEG signal.
iv) Take the FFT of the EEG signal.
v) Plot the half of the sampling frequency components for the x axis.
vi) Plot the fft of the signal frequency verses fft of signal. �

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