NM5K wrote:
I'm not. I'm just trying to show that an antenna can't tell what
is noise, and what is an actual desired signal. To the antenna,
they are both the same. RF.. One can not magically filter noise,
without filtering the actual signals along with it.
This applies more to the small receiving loop, comparing shielded
to non shielded, but also would apply in most any other case.

Say, you have interference with a local origin and a signal with
a remote origin, wouldn't it be possible to tell the two apart?

E.g. by using two antennas. The received signal is the same on
both antennas but the noise is different. This can be used to
cancel out the local noise but keep the remote signal. Phasing boxes
that operate on this principle are commercially available, so maybe
it is possible.

On 6/20/2012 11:14 AM, Rob wrote:
NM5K wrote:
I'm not. I'm just trying to show that an antenna can't tell what
is noise, and what is an actual desired signal. To the antenna,
they are both the same. RF.. One can not magically filter noise,
without filtering the actual signals along with it.
This applies more to the small receiving loop, comparing shielded
to non shielded, but also would apply in most any other case.

Say, you have interference with a local origin and a signal with
a remote origin, wouldn't it be possible to tell the two apart?

E.g. by using two antennas. The received signal is the same on
both antennas but the noise is different. This can be used to
cancel out the local noise but keep the remote signal. Phasing boxes
that operate on this principle are commercially available, so maybe
it is possible.


Sure, but that's a whole different thing entirely.
That's nothing to do with the antennas themselves.

NM5K wrote:
On 6/20/2012 11:14 AM, Rob wrote:
NM5K wrote:
I'm not. I'm just trying to show that an antenna can't tell what
is noise, and what is an actual desired signal. To the antenna,
they are both the same. RF.. One can not magically filter noise,
without filtering the actual signals along with it.
This applies more to the small receiving loop, comparing shielded
to non shielded, but also would apply in most any other case.

Say, you have interference with a local origin and a signal with
a remote origin, wouldn't it be possible to tell the two apart?

E.g. by using two antennas. The received signal is the same on
both antennas but the noise is different. This can be used to
cancel out the local noise but keep the remote signal. Phasing boxes
that operate on this principle are commercially available, so maybe
it is possible.


Sure, but that's a whole different thing entirely.
That's nothing to do with the antennas themselves.

But once you move a bit further away and consider the two antennas
and phasingbox together as a single antenna, it suddenly is capable
of telling apart local noise and distant signal. That is promising.