Frequency Plotting

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% THIS FUNCTION PLOTS FFT OF THE SIGNAL
% INPUT TO THE FUNCTION IS
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%userfft(input, sampling frequency, waveform, psd)
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% input -> Input waveform
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% sampling frequency -> Sampling frequency
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% waveform -> 'real' refers to real baseband signals
% plots only half the fft output
% -> 'complex' refers to complex baseband signals
% plots complete spectrum
% -> 'bandpass'
% psd -> 'unbaised' refers to the fact that fft./length(input)
% -> 'normalised' refers to fft./max(fft)
% -> '' plots fft
%
%
% AUTHOR: ABHI
% CAIRN, WPI
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