Aruba provides several good overviews of 11ac vs 11n, and minimizes product promotion in doing so. Aruba focuses on enterprise WiFi - not consumer.
http://www.arubanetworks.com/techno...rpufgji4grcpqi+sldweygjlv6sgfsrdmmbj1ylglxhy=
NOTE: In the beginning of some of these, the presenter correctly points out that the "Mbps" so claimed in WiFi is the burst bit rate, not the useful yield which we should call "throughput" at the IP layer. But even the presenter fouls up several times referring to raw bit rate as throughput.
Alas, the bane of WiFi marketing - throughput vs. half duplex bit rate.
Also... spatial MIMO streams... laws of physics: the antennas have to be separated by a distance equivalent to x number of wavelengths. At 2.4GHz, the wavelength is about 5 inches. The value of x is very dependent on the kind of end to end path - how line of sight it is/isn't, how much multipath reflection, etc. All this considered, and the cost of multi-stream receivers/combiners, mean only laptops would have a chance at much benefit from 2+ spatial streams. And that is compromised by metal and other objects in the "near field" of the antennas in a laptop (e.g., if in the display portion of the laptop).
Enclosure: Good overviews.
As you listen, beware throughput vs. raw bit rate/burst rate. Remember that 256QAM in 11ac requires a huge signal to noise ratio that leads to 20 ft. of LOS range. Cable modems' downstream often us 256QAM - but cable has the advantage of far less noise and interference as compared to wireless.
http://www.arubanetworks.com/techno...rpufgji4grcpqi+sldweygjlv6sgfsrdmmbj1ylglxhy=
NOTE: In the beginning of some of these, the presenter correctly points out that the "Mbps" so claimed in WiFi is the burst bit rate, not the useful yield which we should call "throughput" at the IP layer. But even the presenter fouls up several times referring to raw bit rate as throughput.
Alas, the bane of WiFi marketing - throughput vs. half duplex bit rate.
Also... spatial MIMO streams... laws of physics: the antennas have to be separated by a distance equivalent to x number of wavelengths. At 2.4GHz, the wavelength is about 5 inches. The value of x is very dependent on the kind of end to end path - how line of sight it is/isn't, how much multipath reflection, etc. All this considered, and the cost of multi-stream receivers/combiners, mean only laptops would have a chance at much benefit from 2+ spatial streams. And that is compromised by metal and other objects in the "near field" of the antennas in a laptop (e.g., if in the display portion of the laptop).
Enclosure: Good overviews.
As you listen, beware throughput vs. raw bit rate/burst rate. Remember that 256QAM in 11ac requires a huge signal to noise ratio that leads to 20 ft. of LOS range. Cable modems' downstream often us 256QAM - but cable has the advantage of far less noise and interference as compared to wireless.
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