Pulsing

The deep waves of power wash through the silence of space, penetrating every inch of earth and sky as they summon up your most subtle feelings. You let your body gently sink down into the dark waters slowly rising around you, where all that is left is the sweet and swiftly fading memory of the pulsing of your breath. In signal processing, the term pulse is a rapid, transient change in the amplitude of a signal from a baseline value to a higher or lower value, followed by a rapid return to the baseline value. Pulse shapes can arise out of a process called pulse-shaping. Optimum pulse shape depends on the application. Rectangular pulses can be found in pulse waves, square waves, boxcar functions, and rectangular functions. In digital signals the up and down transitions between high and low levels are called the rising edge and the falling edge. In digital systems the detection of these sides or action taken in response is termed edge-triggered, rising or falling depending on which side of rectangular pulse. A digital timing diagram is an example of a well-ordered collection of rectangular pulses. A Nyquist pulse is one which meets the Nyquist ISI criterion and is important in data transmission. An example of a pulse which meets this condition is the sinc function. The sinc pulse is of some significance in signal-processing theory but cannot be produced by a real generator for reasons of causality. A Gaussian pulse is shaped as a Gaussian function and is produced by a Gaussian filter. It has the properties of maximum steepness of transition with no overshoot and minimum group delay. This sound uses the following file from Freesound: http://www.freesound.org/samplesViewSingle.php?id=123970