frequenciessuch
frequenciessuch is a hypothetical term used in discussions of spectral analysis to denote the subset of a signal's frequency components that satisfy a predefined constraint. It is not a standard term in mainstream signal processing, but it appears in theoretical discussions and thought experiments as a way to describe frequency elements selected by rules other than amplitude alone.
Formally, for a discrete-time signal x[n] with Fourier transform X(e^{jω}) or its magnitude spectrum |X[k]|, frequenciessuch
Identification is typically done by estimating the spectrum and applying a filter: compute X, evaluate C for
Applications include communications to identify carriers, audio signal processing to isolate meaningful tonal content, and pattern
Origin and status: the term is not widely adopted; it is used mainly in pedagogical or speculative