I've been involved in a wireless co-op for 5+ years and we have observed greater impact on throughput in 802.11b systems from adjacent channel interference than from same channel interference. I speculated that if it's on the same channel the RF energy appears to the access point as properly formatted 802.11 communication packets and these signals are dealt with per the 802.11 protocol -- wrong SSID, not associated = discard. The RF energy from overlapping adjacent channels could just appear as "noise" and therefore lower the S?N ratio on the proper channel, causing the AP to re-negotiate transmission speeds with the clients. This speed-switching (regardless of the cause) wreaks havoc with throughput.
Comments? --John VP La Canada Wireless Association On Jan 3, 2008, at 14:40, Stan Slonkosky wrote: > > On Jan 3, 2008 11:50 AM, Mike Burgess <[EMAIL PROTECTED]> wrote: > >> And who's setting stuff up, and leaveing it on the default >> channels. Come >> on, I always set stuff on 2 or 10, never anybody else there, less >> problems. > > I'm not sure why you'd think that, since there are only three > 802.11b/g channels (1, 6 and 11) that you can use at a time if you > don't want to overlap with another.channel. I read somewhere that you > will actually have more interference problems if you are on a channel > that overlaps with someone else than if you are on the same channel. > > -- > > The input of one of the amateur television repeaters on Santiago Peak > is on 2442 MHz (which is the center of channel 7; see > http://www.scrrba.org/BandPlans/scATVmap.pdf). Last month, I visited > the meeting of the San Bernardino Microwave Society and they broadcast > the meetings via that repeater. The guy who set up the equipment said > that they had suffered interference from the 802.11b/g users and were > now using a 20-Watt amplifier so they wouldn't be bothered by that > interference. I'm not sure what the ERP was, but he was using a dish > antenna. > > The SBMS monthly meeting is the first Thursday of the month, so there > should be a meeting tonight (http://www.ham-radio.com/sbms). > > > -- > Stan Slonkosky > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "SOCALWUG" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/SOCALWUG SOCALWUG website: http://www.socalwug.org -~----------~----~----~----~------~----~------~--~---
