View Single Post
  #58   Report Post  
Old June 12th 10, 10:17 PM posted to rec.radio.amateur.antenna
Cecil Moore Cecil Moore is offline
external usenet poster
 
First recorded activity by RadioBanter: Aug 2006
Posts: 572
Default Where does it go? (mismatched power)

On Jun 12, 12:39*pm, K1TTT wrote:
i don't do s stuff so i have no idea what you just proved... give me
the impedances and voltages/currents.


Too bad about the "s stuff". Here are the RF equations for a Z01 to
Z02 impedance discontinuity in a transmission line. The forward
voltage on the Z01 side is Vfor1 and the reflected voltage from the
impedance discontinuity (back toward the source) is Vref1. The forward
voltage on the Z02 side is Vfor2 and the reflected voltage (from the
load) is Vref2. Hopefully, the reflection and transmission
coefficients are self-explanatory. rho1 is the reflection coefficient
encountered by Vfor1, etc.

Vref1 = Vfor1(rho1) + Vref2(tau2) = 0

That is wavefront cancellation in action. The external reflection
phasor, Vfor1(rho1), is equal in magnitude and 180 degrees out of
phase with the internal reflection phasor, Vref2(tau2), arriving from
the mismatched load.

Vfor2 = Vfor1(tau1) + Vref2(rho2)

If these RF equations are normalized to SQRT(Z0), they are the same as
the s-parameter equations.
--
73, Cecil, w5dxp.com