I had started using UBNT instead of Mikrotik for my MIMO installs because for me, the UBNT gear seemed to work more consistently with less agrevation in noisy environments.
However... Mikrotik appears to do a better job following 802.11n specification. It handles 40Mhz to 20Mhz coexistence properly. If you set the MT AP to 40Mhz, and set the CPE to 20Mhz, it will connect at 20Mhz. Basically, the MT AP will try 40Mhz first, and when it doesn't function it drops to the primary 20Mhz channel for the CPE. It sets the first 20Mhz as the constant base channel. And then MT has a configuration to state whether the second 20Mhz portion will be above or below the primary base. This is useful because you can set the primary base 20Mhz channel to be the channel that is most reliable, to guarantee the base channel is as reliable as possible, and still have the ability to select above or below it for the next best. With this said... I can not comment on interoperabilty with non-Mikrotik gear, nor can I comment on how well the adaptation between 40 and 20 will occur regarding quality, latency or effect on TCP for the traffic passing.. When using Mikrotik I usually recommend restricting the number of Mode possibilities, so that only the modes that work well are available. Other wise the radios spend to much time trying the many variations of modes that might not work well. For example, when interference occurs, does it drop a chain (polarity) or downshift to 20Mhz? Also you'll notice in Mikrotik that you select both the rates it supports and advertises that it supports. This might help with interoperability. Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband ----- Original Message ----- From: "Greg Ihnen" <[email protected]> To: "WISPA General List" <[email protected]> Sent: Saturday, May 21, 2011 6:22 AM Subject: [WISPA] 2.4GHz 802.11n hardware that will do 40MHz and 20MHzchannels simultaneously? >I asked this on the UBNT forum but received no answer. > > The 802.11n specification states that when an AP is set to 40MHz channels > it should allow older gear that's only capable of 20MHz channels to > connect in that mode as well. > > With 2.4GHz UBNT gear I'm finding that if the AP is set to 40MHz then > that's all it will allow clients to connect at - clients that are not > capable of 40MHz channels just don't connect. Apple gear and some others > won't do 40MHz in the 2.4GHz band. > > Does anyone know if there's any cards that could be used the MT > routerboards that could do both 40MHz and 20MHz channels simultaneously? > > Thanks! > Greg > > > -------------------------------------------------------------------------------- > WISPA Wants You! Join today! > http://signup.wispa.org/ > -------------------------------------------------------------------------------- > > WISPA Wireless List: [email protected] > > Subscribe/Unsubscribe: > http://lists.wispa.org/mailman/listinfo/wireless > > Archives: http://lists.wispa.org/pipermail/wireless/ -------------------------------------------------------------------------------- WISPA Wants You! Join today! http://signup.wispa.org/ -------------------------------------------------------------------------------- WISPA Wireless List: [email protected] Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
