On Tue, 2004-01-20 at 17:11, Martin Usher wrote:
> It sounds like you're reciving a radar signal. The UNI/2 band has a conflict
> with some airport radars -- particularily in Europe -- so a condition of
> using these frequencies is that your equipment has code in it to detect and
> avoid conflicts with radars.
> Detection involves looking at the timing of these error packets for a "radar
> like" pattern. The production code stores the timestamps of these errors in
> a circular buffer, periodically scanning this buffer for likely looking
> patterns. If it detects a pattern that it thinks is a radar then it restarts
> the BSS (or IBBS) using a different channel. (Note that you don't use this
> in an ISS's stations -- stations don't do active probes and take their cue
What if the station does active scanning ?
> as to what channel to use from the AP.)
> Information about this requirement can be found in the ETSI document "EN 301
I just read this document. However, what I observe does not seem to be
covered by the document since I am operating in channel 1 (2.412GHz),
mode 802.11B, 11Mb/s and the document seems to be interested only in the
5GHz frequency range. Am I wrong ?
I'll try to see if I get similar results using other channels.
> When we first came across this it sounded like a typical load of
> bureaucratic BS because the requirements seemed to be a bit pliable, the
> testing methodology seemed a bit fluid and nobody had a handy radar to try
> things against to see if there really was such a conflict. Mathiu's
> observations seem to vindicate the bureaucrats [:-(]. Oh well.
thanks for your detailed answer,
Mathieu Lacage <mathieu.lacage@...>