Owen Duffy wrote:
Cecil Moore wrote in news:vyMSh.13914$JZ3.5605
@newssvr13.news.prodigy.net:

Virtual reflection coefficients, such as the ones used by

What is a "Virtual reflection coefficients"?

SQRT(Pref/Pfor) which often differs from the
physical reflection coefficient (Z02-Z01)/(Z02+Z01)

Here's an example:

100W---50 ohm line--+--1/2WL 300 ohm line--50 ohm load

The virtual reflection coefficient looking into point
'+' from the source side is SQRT(Pref/Pfor) = 0

The physical reflection coefficient looking into point
'+' from the source side is (300-50)/(300+50) = 0.7143

The virtual reflection coefficient is an effect. The
physical reflection coefficient is associated with
the causes of reflections. The S-Parameter reflection
and transmission coefficients are physical. There
are *always* reflections at a physical impedance
discontinuity but they are often zeroed out by
wave cancellation.
--
73, Cecil http://www.w5dxp.com