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Richard Clark

On 22 Aug 2006 16:28:09 -0700, wrote:

Why would there be a significant problem in the first place....
these aren't CW devices, they are Packetized Spread Spectrum
and two devices next to each other, even on the same channel, would
not run into each other, due to different spreading code roots
anyway..... Hmmmmm, non problem, from where I sit.....

I'm running 802.11b @ 2.4Ghz. As I understand it at 11Mbps (which I'm
using) the signal is "spread" using the CCK code, and each packet/user
uses the same spreading function. So a transmission only goes forward
if the channel is "empty", i.e. the received power at the transmitter
is below some carrier sense threshold (dBm)......

Hi All,

Spread Spectrum is merely the 0 level of the protocol stack and has
nothing to do with "going forward." That is a software issue at a
much higher level that deals with packet collisions. The hardware may
augment collision detection through carrier sense (which would only
occur if both share the same code). In fact, thresholds may be well
below the noise floor (dBm) and still work with notably lower
throughput, but this is an even more remote issue, except you may be
fighting poor isolation from even the best of isolators.

73's
Richard Clark, KB7QHC