ok Guys so in this example: eCee with 5400 means;
"C" is a central frequency?
So 5400 means range 5390-5410
5400 eCee spectrum range should be
All Frequency setting are central.
C = control channel
Yes, and its 20Mhz wide. Every "e" means another 20Mhz wide channel that is attached to the first, 'center' frequency.
Any client that connects to this AP should at least be able to 'talk' on the center frequency.
ac protocol now actually is smart enough to 'sense' if one of the other 'e' channels has interference and skips this channel for immediate usage. It still communicates with cpe on the other 'c' and 'e' channels, but with less speed than the theoretical max. off course.
So, if AP works 5600 eCee (=80Mhz) it can connect to station that is set to 5600 'C' or 5600 'eCe' or 'eCee' and probably (?) even on 'Ce'. (This is a presumption from my end. Don't know for sure and since no ac radios yet, can't test it.)
If AP works on 5600 eCee representing 5570-5590+5590-5610+5610-5630+5630-5650 and station works on same, but the protocol 'senses' (its described on the internet somewhere, can't remember where
) that for instance on 5610-5630 the signal is disturbed (I believe AP 'tests' each channel to get a sort of CCQ value, if its poor it omits using that channel for data transport) it won't use that channel. But the other 3 available channels are still used for data. Maximum throughput is now obviously lowered to a level that belongs a 3 channel wide bandwidth.
The nice thing is now that interference is often a variable event, and traffic demand is also often variable.
You can now setup a 80Mhz wide backhaul link in an area that has many other wifi usages. At times it CAN handle its full potential (when all channels are 'clean') but when due atmospheric circumstances or whatever suddenly one of the underlying 20Mhz channels gets hammered, the backhaul still delivers a high quality link, only a bit lower in maximum throughput.
If you compare this to a normal 'n' or 'a' channel set backhaul link which become very unstable and unreliable in case of interferences, this 'ac' channel setup has a bit of what I would call "interference avoidance technology".
[On 'n' based backhaul you have to pick a 40Mhz wide channel you hope is free. You might get for instance 150Mb real data throughput if the spectrum stays free. If you now need to guarantee 150Mb data you can opt to use an 'ac' backhaul. Set it to 80Mhz and pick some centre channel that seems to be relatively free. Run it and under the same 'clean spectrum' circumstances as with the 'n' link you'll get even higher throughputs (up to 800Mb). BUT, more important, you can sleep in peace, because even some disturbing radio waves that will molest part of your channels is not going to ruin your link. Actually you can 'lose' 2 out of the 4 channels to still be able to deliver 150Mb real data! You backhaul suddenly became much more reliable than one based on 'n'. At a fraction more expenses than the 'n' link. Ain't that marvellous!
Off course, when you're continuously seeking the maximum in a 80Mhz (or 120Mhz!) wide channel you'd better move your link to the Sahara desert, or the moon
If such high throughput (1.8Gb!) is required, you might think of other solutions.
IN an indoor environment where both AP and stations all support ac and have good signal (256 QAM 5/6 !) and you have no close range other wifi signals you might see it happen!
You can then swap your pirate-bay files (!) from one device to another in minutes of time....well... lucky you.
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Rudy R. Puister
WISP operator based on MT routerboard & ROS.