vimwiki/tech/PEP.wiki

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= PEP =
Peak envelope delivery or PEP is the average power of onc ecomplete RF cycle at
the peak of the singal envelope. It is important to note that it IS NOT the
power at the peak of an RF cycle during a peak of the signal's envelope.
PEP is used as it is a convient way to portray the max power of an amplitude
modulated signal.
== Calcuation ==
To calculate PEP, you need to know the [[Impedance]] and [[AC#RMS|RMS]].
You can also calcuate it using the Peak Envelope Power (PEV), or the peak
amplitude of one side band, or the Peak to Peak voltage (V,,p-p,,). V,,p-p,,
is found by doubling the PEV, or taking the max voltage of both sidebands.
PEP is euqal to the average power if an amplitude-modulated signal is not
modulated. This is the case when modulation is removed from an [[Modulation#AM]] signal, or
with [[Modulation#CW]] keying. Because [[Modulation#FM]] signals are constant
power, the PEP is always equal to average power for FM signals. In other words,
if an average reading Wattmeter reads 1060W output when CW keying, then your
PEP output is also 1060W.
The way to calculate it is shown below
PEP = V,,RMS,,^2 / R
PEP = ((0.707 * V,,p-p,,) / 2)^2 / R
PEP = (PEV * 0.707)^2 / R
Where R is the loads [[Impedance]]. For example,
Peak envelope voltage (PEV) is 50V across a 50ohm load. PEP is
PEP = (50 * 0.707)^2 / 50
PEP = 25W
A 50ohm load is dissipating a 1200W PEP, the RMS voltage is
1200 = V,,RMS,,^2 / 50
60000 = V,,RMS,,^2
244.948 = V,,RMS,,