Setting Channel in a crowded neighbourhood.

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KeithSloan
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Setting Channel in a crowded neighbourhood.

Post by KeithSloan » Fri Jan 19, 2007 6:00 pm

I am not sure were I got the impression from, but my understandings is that Channels overlap and that to get total isolation you have to be quite a number of channels away. If one person starts at 1 then the next channel that does not overlap is 6 and then the one after 11. Is this correct?

If it is correct what were the designers thinking of, surely we would be better off with just 3 channels and less chance of overlaping.

I was at my sisters house and she gets problems from 6-8pm in the evening. I installed Net Stumbler which showed that at one stage there were 6 networks active :(

Netstumbler showed some strange things, when we changed the channel it would show the new channel but also list the old. It also regulary switched to the old channel about 1/5 of the time. What is going on here.

I also saw another router switching between channel 1 and 9. It seemed to spend 50% on each. Are there routers that use more than one channel.

One router strong single so close by seemed to follow us. So if we when to channel 11 it would add 11 to its list but not first in list, but did not seem to switch to 11, again what is going on.

Question if one sees a network and the signal is weak assuming that its a good candidate for not overlapping is it okay to use it. i.e. Will our signal swamp it and its signal only show up in our signal to noise. Or do channels still interfere even if weak.

I am sure I had other questions but this will do for now.
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Neo
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Post by Neo » Fri Jan 19, 2007 6:12 pm

Deleted the duplicate post/thread.

Channels do overlap to some extent - see HERE

They overlap to maximise the use of the spectrum - if they were spread apart then the spectrum wouldn't be used very efficiently and the number of potential operating wifi devices would reduce.

Edit: The actual channel numbering is arbitrary, as the electromagnetic spectrum is continuous rather than discrete in nature. As the link shows, we could call them A (1), B (6) and C (11) :)

If it were possible then the manufacturers would make each channel narrow enough not to overlap, but the spread spectrum technology used to encode the transmissions works by spreading the signal over a relatively wide spectrum, so it's unavoidable. SS is used to reduce susceptibility to interference.

See THIS also ;)
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