> Bringing up a very interesting point... Is it
theoretically possible (with
> unlimited processing power and perhaps a lot of receiving
elements
> available) to cancel the noise? After all, a gain antenna
helps a bit
> (because it "sees" less of the noise), but that's a
directivity thing, not
> a "gain" thing.
I started trying this in the 70's Jim. Signal phase and
level varies rapidly even at distances as close as several
hundred feet on 160 meters. That means when combining
elements spaced over a distance of a few wavelengths, the
combining system would have to recognize and track a desired
signal. That's a big technical problem for random signals on
random frequencies.
I can't directly combine arrays spaced more than 1000 feet
or so on 160 meters with manual or fixed phasing, and
automatic phasing is not practical with noise floor random
signals.
What I settled on is using the largest possible size antenna
array, and then picking wider spaced cells as "pairs" to run
in stereo on phased locked receivers. The more directivity
you can get in a limited area, the better it will work.
73 Tom
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