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Old May 8th 12, 01:22 PM posted to uk.rec.audio
Arny Krueger[_2_]
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Posts: 200
Default Wireless transmitter


"Jim Lesurf" wrote in message
...
In article , Arny
Krueger
wrote:



Right, but the efficiency of spread spectrum gear does decrease if some
of the frequencies that are hopped to are always useless due to a
stable interferring source.


Much the same effect can occur when two (or more) hopping systems try to
use the same band - unless you have a common strategy they can adopt/agree
to avoid each other as they do so.


As a rule wi-fi devices don't have adaptive strategies.

Indeed, when one hopping system
encounters another it can't simply chalk up "avoid slot N" as it can to
avoid clashes with a static transmission in a slot.


Wi fi frequency hopping strategies appear to be simplistic.

So adaptive hopping can
actually work better against a static-slot interference than another
transmission that hops in a way it can't predict.


Right. In some ways Wi Fi is like 10BT ethernet all over again. Its
simplistic strategies and low data rate lead to slow and unreliable
transmission rates due to contention, even when actual usage is relatively
low. Ethernet over wire was somewhat rejuvinated by two order-of-magnitude
increases in basic transmission rates.