amplitúdói

Amplitúdói is a term used in signal analysis to denote the amplitude envelopes of time-varying signals. In practical use, an amplitúdói represents the slowly varying function that modulates the strength of a carrier signal, separating amplitude information from phase information. The concept is closely related to the envelope of the analytic signal, where for a real signal x(t) its analytic representation is x_a(t) = x(t) + j H{x(t)}, and the envelope is A(t) = |x_a(t)|. In many Hungarian-language texts the noun amplitúdó and the plural amplitúdói are used to refer to this envelope function.

Mathematically, a modulated carrier can be written as s(t) = A(t) cos(ωc t + φ(t)), where A(t) ≥ 0 is the amplitúdói, ωc is the carrier angular frequency, and φ(t) is the instantaneous phase. When A(t) varies slowly compared with ωc, standard amplitude modulation theory applies, and A(t) captures modulation depth and timing. The amplitúdói is typically nonnegative, differentiable or piecewise smooth, and bounded.

Construction and recovery: A(t) can be obtained from s(t) by analytic signal methods or envelope detection, for example via the Hilbert transform or a rectifier followed by a low-pass filter. In multi-component signals, separate amplitúdói can describe the envelopes of individual components.

Applications: Amplitúdói are central in AM radio, audio synthesis, speech processing, and vibration analysis. They also appear in time–frequency analyses to characterize transient amplitude changes. The term is most common in Hungarian-language literature; in English, the envelope or instantaneous amplitude terminology is more widely used.