MATLAB Code for Fourier Series Handling (with FFT)

The MATLAB FFT/IFFT functions are good but not so easy to use for real periodic signal:

• the ordering of the frequency vector is confusing due to the negative frequencies (spectrums are symmetric)
• the coefficients are not scaled as in a Fourier series due to the definition of the DFT

The provided MATLAB functions offer different functionalities around Fourier series:

• get time and frequency vector
• wrappers around the MATLAB FFT/IFFT functions that scale periodic signals as Fourier series coefficients
• many signals can be processed at the same time (matrices)

The following functions are offered for signal generation:

• generate spectrum of arbitrary PWM periodic signals directly in the frequency domain
• generate PWM signals with a finite/infinite slew rate
• generate DC and AC sinusoidal signals

Additionally, several transformations can be applied to frequency domain signals:

• apply low-pass filters (e.g., first-order, second-order)
• apply simple transformations (eg., delay, phase shift, AC coupling)

Examples

Compatibility

• Tested with MATLAB R2018b and R2021b.
• No toolboxes are required.
• Compatibility with GNU Octave not tested but probably easy to achieve.

Author

Thomas Guillod - GitHub Profile

License

This project is licensed under the BSD License, see LICENSE.md.