sagedusruumi
Sagedusruum, or frequency space, is a way of describing signals by their frequency components rather than by time. In this domain, a time-domain signal x(t) is transformed into a spectrum X(f) by a Fourier transform, revealing the signal's spectral content. The magnitudes |X(f)| indicate how much of each frequency is present, while the phase of X(f) encodes the timing of the sinusoidal components. Continuous-time signals use the continuous Fourier transform, while discrete-time signals use the discrete-time Fourier transform or the discrete Fourier transform. The frequency axis is typically measured in hertz for continuous transforms or in radians per sample for digital transforms.
Key properties include linearity and invertibility (subject to normalization). The convolution theorem states that convolving a
Applications span spectrum analysis, filtering and equalization, communications, audio and image processing, and scientific data analysis.
Limitations include the loss of time localization in a pure frequency-domain representation; time-frequency methods, such as
In science and engineering, frequency-space analysis helps describe wave behavior, energy spectra, and signal propagation.