Mathematica definitions

Load needed packages for this notebook

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Set up defaults

Turn off annoying warning messages
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Set default options for specific functions
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Visualization functions

Fix time variable for sampled signals
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Generate periodic waveform from one period

PeriodicSignal[f, {dmin, dmax}, {t, min, max}] generates a periodic waveform for the interval [min, max]. It is assumed that one period of the function f(t) is defined over the interval [dmin, dmax].

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Plot periodic waveforms

PeriodicPlot[f, {dmin, dmax}, {t, min, max}, opts] plots a a periodic waveform for the interval [min, max]. It is assumed that one period of the function f(t) is defined over the interval [dmin, dmax]. The 'opts' argument passed plotting options to the Mathematica function Plot[ ].

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Plot discrete-time signal as sequence of amplitude lines
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Plot discrete-time signal as sequence of amplitude lines
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Fourier rearrange

FourierRearrange[fft] rearranges the result of an FFT (Mathematica function Fourier[ ]), to a easier to visualize the spectrum represented by 'fft'. The length of the list 'fft' is assumed to be even; if it is not, the last term in 'fft' is dropped.

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Short-cut functions

Dirac delta function
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Unit step function
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Pulse of width [Graphics:../Images/index_gr_12.gif]
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Hack to plot [Graphics:../Images/index_gr_14.gif]

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Sampler (CT to DT converter)

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Sampled frequency spectrum

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Definition of DTFT

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Definition of DFT

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Definition of spectral leakage window

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Converted by Mathematica      March 25, 2003