STFT divides a signal into shorter segments for analysis
Short-time Fourier transform
STFT divides a signal into shorter segments for analysis
The short-time Fourier transform (STFT) analyzes a signal by dividing it into shorter segments, allowing for the examination of its frequency content over time. This method provides a detailed view of how the signal's frequency spectrum changes, which is crucial for understanding non-stationary signals.
Example
Consider a signal composed of a 440 Hz tone that gradually shifts to 880 Hz over 5 seconds. Using STFT, the signal is divided into 1-second segments. The Fourier transform is computed for each segment, revealing the frequency content at each time point.
STFT is essential for analyzing signals with time-varying frequency content, such as audio signals or communications signals.
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