what happens to reflected energy ?
On Jun 6, 10:22*am, "JC" wrote:
Basic question (at least for me) for a very poor antenna matching :
-100 w reach the antenna and 50 w are radiated.
- 50 w are "reflected", what is their fate ?
Are they definitely lost for radiation and just heat the line, the final.....
JC
I assume that your numbers were obtained using a directional
wattmeter,
that is, forward power is 100W, 50W are reflected and by subtraction,
it is computed that 50W enter the antenna, some of which is dissipated
in the antenna losses and some of which is radiated.
The 100W forward and 50W reflected have no relation to actual powers
but
are simply values that are constructed so that when they are
subtracted
the result is the average power flowing towards the load.
From these numbers alone it is impossible to decide whether the system
is operating as it should or to compute where the losses might be, or
whether there are any losses at all. With an appropriate antenna tuner
it is entirely possible that the transmitter is delivering its design
output of 50W to the line and all of this energy is reaching the
antenna and being radiated.
Thus the whole question of "where does the reflected power go?", is
rather misleading.
....Keith
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