Changes

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*[http://en.wikipedia.org/wiki/16th_century 1542]

*[https://en.wikipedia.org/wiki/16th_century 1542]

==Definitions==

==Definitions==

*1: extent of [[dignity]], excellence, or splendor

*1: extent of [[dignity]], excellence, or splendor

The '''amplitude''' of a periodic [[variable]] is a measure of its [[change]] over a single period (such as [[time]] or spatial period). There are various [[definitions]] of amplitude which are all functions of the magnitude of the [[difference]] between the variable's [[extreme]] [[values]].

The '''amplitude''' of a periodic [[variable]] is a measure of its [[change]] over a single period (such as [[time]] or spatial period). There are various [[definitions]] of amplitude which are all functions of the magnitude of the [[difference]] between the variable's [[extreme]] [[values]].

In general, the use of [http://en.wikipedia.org/wiki/Amplitude#Peak_amplitude peak amplitude] is simple and unambiguous only for [[symmetric]] periodic [[waves]], like a sine wave, a [http://en.wikipedia.org/wiki/Square_wave square wave], or a triangular wave. For an asymmetric wave (periodic [[pulses]] in one direction, for example), the peak amplitude becomes [[ambiguous]]. This is because the value is [[different]] depending on whether the maximum positive signal is measured [[relative]] to the mean, the maximum negative signal is measured relative to the mean, or the maximum positive signal is measured relative to the maximum negative signal (the [http://en.wikipedia.org/wiki/Amplitude#Peak-to-peak_amplitude peak-to-peak amplitude]) and then divided by two. In electrical engineering, the usual solution to this ambiguity is to measure the amplitude from a defined reference potential (such as [http://en.wikipedia.org/wiki/Ground_(electricity) ground] or 0 V). Strictly speaking, this is no longer amplitude since there is the possibility that a constant (DC component) is included in the measurement.

In general, the use of [https://en.wikipedia.org/wiki/Amplitude#Peak_amplitude peak amplitude] is simple and unambiguous only for [[symmetric]] periodic [[waves]], like a sine wave, a [https://en.wikipedia.org/wiki/Square_wave square wave], or a triangular wave. For an asymmetric wave (periodic [[pulses]] in one direction, for example), the peak amplitude becomes [[ambiguous]]. This is because the value is [[different]] depending on whether the maximum positive signal is measured [[relative]] to the mean, the maximum negative signal is measured relative to the mean, or the maximum positive signal is measured relative to the maximum negative signal (the [https://en.wikipedia.org/wiki/Amplitude#Peak-to-peak_amplitude peak-to-peak amplitude]) and then divided by two. In electrical engineering, the usual solution to this ambiguity is to measure the amplitude from a defined reference potential (such as [https://en.wikipedia.org/wiki/Ground_(electricity) ground] or 0 V). Strictly speaking, this is no longer amplitude since there is the possibility that a constant (DC component) is included in the measurement.

In [http://en.wikipedia.org/wiki/Telecommunication telecommunication], [http://en.wikipedia.org/wiki/Amplitude#Pulse_amplitude pulse amplitude] is the magnitude of a pulse parameter, such as the [http://en.wikipedia.org/wiki/Voltage voltage] level, current level, [http://en.wikipedia.org/wiki/Field_intensity field intensity], or power level.

In [https://en.wikipedia.org/wiki/Telecommunication telecommunication], [https://en.wikipedia.org/wiki/Amplitude#Pulse_amplitude pulse amplitude] is the magnitude of a pulse parameter, such as the [https://en.wikipedia.org/wiki/Voltage voltage] level, current level, [https://en.wikipedia.org/wiki/Field_intensity field intensity], or power level.

Pulse amplitude is measured with respect to a specified reference and therefore should be modified by qualifiers, such as "[[average]]", "instantaneous", "peak", or "root-mean-square".

Pulse amplitude is measured with respect to a specified reference and therefore should be modified by qualifiers, such as "[[average]]", "instantaneous", "peak", or "root-mean-square".

Pulse amplitude also applies to the amplitude of [[frequency]]- and phase-modulated waveform envelopes.[http://en.wikipedia.org/wiki/Amplitude]

Pulse amplitude also applies to the amplitude of [[frequency]]- and phase-modulated waveform envelopes.[https://en.wikipedia.org/wiki/Amplitude]

 

[[Category: Physics]]

[[Category: Physics]]