Difference between revisions of "Pulsation"

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

Latest revision as of 02:32, 13 December 2020

Lighterstill.jpg

Wdpulse.gif

Etymology

Middle English puls, from Anglo-French, from Latin pulsus, literally, beating, from pellere to drive, push, beat

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
b : the palpable beat resulting from such pulse as detected in a superficial artery; also : the number of individual beats in a specified time period (as one minute) <a resting pulse of 70>
  • 2 a : underlying sentiment or opinion or an indication of it
b : vitality
b : beat, throb
  • 4 a : a transient variation of a quantity (as electric current or voltage) whose value is normally constant
b (1) : an electromagnetic wave or modulation thereof of brief duration (2) : a brief disturbance of pressure in a medium; especially : a sound wave or short train of sound waves
  • 5 : a dose of a substance especially when applied over a short period of time <pulses of intravenous methylprednisolone>

Description

In 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.
  • 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 can arise out of a process called pulse-shaping. Optimum pulse shape depends on the application.

  • Rectangular pulse

These 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.

  • Nyquist pulse

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.

  • Gaussian pulse

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.[1]