Thread: IBOC
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Old February 23rd 04, 12:07 AM
Frank Dresser
 
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"Telamon" wrote in message
...


Data communications occupy wider bandwidths than the stated clock

rate.
It is not unreasonable to expect harmonics 3 to 5 times the clock rate
because the signaling uses square waves and there is significant power
in the odd harmonics.

--
Telamon
Ventura, California


A square wave, itself, won't convey much information. It needs to be
modulated, and the modulation would have to effect the symmetry and
result in both odd and even harmonics.

I don't know what sort of modulation BPL is using. I can imagine
hundreds of low amplitude sine wave carriers from 2 to 60 Mhz, all of
them phase modulated. In that case, I don't think there would be much
harmonic output. This would certainly still be a big problem for the
radio hobbyist, but not so much for the FM/TV user. There have been
several BPL tests in various communities, and it doesn't seem to have
wiped out normal broadcast use.

If BPL caused enough bothersome interference to keep people in the test
communities from their TVs and radios, the National Association of
Broadcasters would have squashed it like a bug.

Frank Dresser