Owen Duffy wrote:
You assertion that you have travelling forward and reflected power waves
on the transmission line runs into a problem when you try to analyse the
combination of both at a point (eg the input to the line) as power
doesn't combine vectorially.

But it does combine according to the following formula
which is the irradiance equation from the field of
optics.

Ptot = P1 + P2 + 2*SQRT(P1*P2)cos(A)

where 'A' is the angle between V1 and V2 and V1 is
the voltage associated with P1 and V2 is the voltage
associated with P2.

The first time I saw this equation was in Dr. Best's
Nov/Dec 2001 QEX article on Transmissions Lines. It
really does work for "adding" the two powers in two
coherent waves.
--
73, Cecil http://www.w5dxp.com