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Old February 23rd 11, 08:42 PM posted to rec.radio.amateur.antenna
Richard Clark Richard Clark is offline
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First recorded activity by RadioBanter: Jul 2006
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Default No comment three antennas - duplex

On Wed, 23 Feb 2011 09:29:56 -0800, Jim Lux
wrote:

In these sorts of systems (the ones alluded to in the original news
story), all the signals are in one FPGA (in digital form) and the powers
are fairly low so all the RF stuff runs basically linear (DC to RF
efficiency isn't a huge deal on a 50mW transmitter next to a 10 Watt FPGA)


This seems to be straying from what this is about: an antenna system.
You seem to imply that the 10W FPGA is a source of radiation to
confound things. How that arrived, I don't know.

The presence of uncontrolled reflecting surfaces in proximity to the
antenna system is the objection, and the introduction of unintended
out-of-phase reflection transmission signals combined with intended
receive signals present at the receiving antenna yields the classic
problem of S+N/N degradation.

So it *is* a wireline hybrid bridge.. but done with numbers instead of
transformer windings.


This does not answer the objection. Reality (conventional usage) will
bring these corrupting out-of-phase signals and the best that software
can offer is a regression of retries to obtain error corrected packets
sorted out a the cost of seriously depressed through-put rates.

This "invention" is more about being clever than useful and belongs in
a museum case next to the Babel Fish (whose utility is questionable
when you have to listen to Vogon poetry).

73's
Richard Clark, KB7QHC