Search results
Results From The WOW.Com Content Network
In physics and engineering, the envelope of an oscillating signal is a smooth curve outlining its extremes. [1] The envelope thus generalizes the concept of a constant amplitude into an instantaneous amplitude. The figure illustrates a modulated sine wave varying between an upper envelope and a lower envelope. The envelope function may be a ...
Illustration of the envelope (the slowly varying red curve) of an amplitude-modulated wave. The fast varying blue curve is the carrier wave, which is being modulated. The amplitude of a wave may be constant (in which case the wave is a c.w. or continuous wave), or may be modulated so as to vary with time and/or
Since the amplitude to travel from x to y after a time t + t ' can be considered in two steps, the propagator obeys the composition identity, (;) (; ′) = (; + ′) , which can be interpreted as follows: the amplitude to travel from x to z in time t + t ' is the sum of the amplitude to travel from x to y in time t, multiplied by the amplitude ...
Amplitude envelope refers to the changes in the amplitude of a sound over time, and is an influential property as it affects perception of timbre. A flat tone has a steady state amplitude that remains constant during time, which is represented by a scalar.
The group velocity is positive (i.e., the envelope of the wave moves rightward), while the phase velocity is negative (i.e., the peaks and troughs move leftward). The group velocity of a wave is the velocity with which the overall envelope shape of the wave's amplitudes—known as the modulation or envelope of the wave—propagates through space.
The most common form of damping, which is usually assumed, is the form found in linear systems. This form is exponential damping, in which the outer envelope of the successive peaks is an exponential decay curve. That is, when you connect the maximum point of each successive curve, the result resembles an exponential decay function.
In physics, slowly varying envelope approximation [1] (SVEA, sometimes also called slowly varying asymmetric approximation or SVAA) is the assumption that the envelope of a forward-travelling wave pulse varies slowly in time and space compared to a period or wavelength.
In sound and music, an envelope describes how a sound changes over time. For example, a piano key, when struck and held, creates a near-immediate initial sound which gradually decreases in volume to zero. An envelope may relate to elements such as amplitude (volume), frequency (with the use of filters) or pitch.