This example illustrates how the DSP System Toolbox™ implements the spectral analysis method known as the periodogram. A periodogram computes the spectral content of a signal over time, often for a real-time input signal.
The input signal is a segment of speech voicing the word "MATLAB". The signal is buffered into frames, with 128 samples per frame. Each frame is then windowed using a Hamming window function, and an FFT is computed for the windowed frame. The system collects the FFTs for successive frames and plots them to produce a spectrogram.