Changes

[[File:lighterstill.jpg]][[File:Alcorn_colorpulsation.jpg|right|frame]]

[[File:lighterstill.jpg]][[File:Wdpulse.gif|right]]

==Etymology==

==Etymology==

[http://nordan.daynal.org/wiki/index.php?title=English#ca._1100-1500_.09THE_MIDDLE_ENGLISH_PERIOD Middle English] puls, from Anglo-French, from [[Latin]] pulsus, [[literally]], beating, from pellere to drive, push, beat  

[https://nordan.daynal.org/wiki/index.php?title=English#ca._1100-1500_.09THE_MIDDLE_ENGLISH_PERIOD Middle English] puls, from Anglo-French, from [[Latin]] pulsus, [[literally]], beating, from pellere to drive, push, beat  

*Date: [http://www.wikipedia.org/wiki/14th_Century 14th century]

*Date: [https://www.wikipedia.org/wiki/14th_Century 14th century]

==Definitions==

==Definitions==

*1 a : the regular expansion of an artery caused by the ejection of blood into the arterial [[system]] by the contractions of the [[heart]]  

*1 a : the regular expansion of an artery caused by the ejection of blood into the arterial [[system]] by the contractions of the [[heart]]  

==Description==

==Description==

In [http://en.wikipedia.org/wiki/Signal_processing signal processing], the term '''pulse''' has the following [[meanings]]:

In [https://en.wikipedia.org/wiki/Signal_processing signal processing], the term '''pulse''' has the following [[meanings]]:

*1. 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.

*1. 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.

*2. A rapid change in some characteristic of a signal, e.g., [[phase]] or [[frequency]], from a baseline value to a higher or lower value, followed by a rapid return to the baseline value.

*2. A rapid change in some characteristic of a signal, e.g., [[phase]] or [[frequency]], from a baseline value to a higher or lower value, followed by a rapid return to the baseline value.

*Pulse shapes

*Pulse shapes

'''Pulse''' shapes can arise out of a [[process]] called [http://en.wikipedia.org/wiki/Pulse_shaping pulse-shaping]. Optimum pulse shape depends on the [[application]].

'''Pulse''' shapes can arise out of a [[process]] called [https://en.wikipedia.org/wiki/Pulse_shaping pulse-shaping]. Optimum pulse shape depends on the [[application]].

*Rectangular pulse

*Rectangular pulse

These can be found in [http://en.wikipedia.org/wiki/Pulse_wave pulse waves], [http://en.wikipedia.org/wiki/Square_wave square waves], [http://en.wikipedia.org/wiki/Boxcar_function boxcar functions], and [http://en.wikipedia.org/wiki/Rectangular_function 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 [http://en.wikipedia.org/wiki/Digital_timing_diagram digital timing diagram] is an example of a well-ordered [[collection]] of rectangular pulses.

These can be found in [https://en.wikipedia.org/wiki/Pulse_wave pulse waves], [https://en.wikipedia.org/wiki/Square_wave square waves], [https://en.wikipedia.org/wiki/Boxcar_function boxcar functions], and [https://en.wikipedia.org/wiki/Rectangular_function 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 [https://en.wikipedia.org/wiki/Digital_timing_diagram digital timing diagram] is an example of a well-ordered [[collection]] of rectangular pulses.

*Nyquist pulse

*Nyquist pulse

A Nyquist pulse is one which meets the [http://en.wikipedia.org/wiki/Nyquist_ISI_criterion Nyquist ISI criterion] and is important in [[data]] transmission. An example of a pulse which meets this condition is the [http://en.wikipedia.org/wiki/Sinc_function 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 Nyquist pulse is one which meets the [https://en.wikipedia.org/wiki/Nyquist_ISI_criterion Nyquist ISI criterion] and is important in [[data]] transmission. An example of a pulse which meets this condition is the [https://en.wikipedia.org/wiki/Sinc_function 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]].

*Gaussian pulse

*Gaussian pulse

A Gaussian pulse is shaped as a [http://en.wikipedia.org/wiki/Gaussian_function Gaussian function] and is produced by a [http://en.wikipedia.org/wiki/Gaussian_filter Gaussian filter]. It has the properties of maximum steepness of [[transition]] with no overshoot and minimum [http://en.wikipedia.org/wiki/Group_delay group delay].[http://en.wikipedia.org/wiki/Pulse_%28signal_processing%29]

A Gaussian pulse is shaped as a [https://en.wikipedia.org/wiki/Gaussian_function Gaussian function] and is produced by a [https://en.wikipedia.org/wiki/Gaussian_filter Gaussian filter]. It has the properties of maximum steepness of [[transition]] with no overshoot and minimum [https://en.wikipedia.org/wiki/Group_delay group delay].[https://en.wikipedia.org/wiki/Pulse_%28signal_processing%29]

[[Category: Physics]]

[[Category: Physics]]

[[Category: Music]]

[[Category: Music]]