Symbolics > Working with Symbolics > Calculus > Example: Fourier Transform Pairs
  
Example: Fourier Transform Pairs
Define the period, the sampling frequency, and the number of samples of a signal.
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Sinusoidal Signal
1. Use symbolic evaluation to find the Fourier transform of a sinusoidal signal.
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Rearranging the terms of the result gives:
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The result shows two components involving the Dirac delta (unit impulse) Δ function.
2. Use the sin function to define a sinusoidal signal.
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3. Plot the first few elements of function f1.
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4. Use the dft function to find the Discrete Fourier Transform of the signal.
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5. Plot the two components of the Fourier Transform of the function. Use vertical markers to show where they occur relative to the sampling frequency.
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Square Pulse (boxcar) Signal
1. Use the Heaviside step function Φ to define a square pulse signal.
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2. Plot the first few elements of function f2.
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3. Use the dft function to find the discrete Fourier transform of the square pulse signal.
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4. Plot the Fourier Transform of the square pulse signal. Use vertical markers to show where they occur relative to the sampling frequency.
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Gaussian Signal
1. Define the following Gaussian signal.
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2. Plot the first few elements of function f3.
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3. Use the dft function to find the discrete Fourier transform of the Gaussian signal.
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4. Plot the Fourier Transform of the Gaussian signal. Use vertical markers to show where they occur relative to the sampling frequency.
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