Ryhmäviiveen
Ryhmäviiveen, or group delay in English, is a fundamental concept in signal processing, communications engineering, and acoustics. It describes how the phase of a signal’s frequency components is shifted as the signal propagates through a medium or component. The group delay is defined as the negative derivative of the phase response with respect to angular frequency, τ_g(ω) = –dφ(ω)/dω, where φ(ω) is the phase shift introduced by the system. This quantity represents the time delay experienced by the envelope of a narrowband signal or a group of frequencies.
Group delay differs from phase delay, which is the simple phase shift divided by frequency, and from
Typical values of group delay in a low‑pass RC filter can be derived analytically; for a first‑order
Measurement of group delay is performed using vector network analyzers or time‑domain reflectometers by launching known
Historically, the term originates from group velocity in physics and was adopted in electronics in the 1940s