Performance Comparison for 802.11ac Draft and 802.11n
I recently wrote a small forecast forecast for 802.11ac . The first hardware with support for 802.11ac Draft and the first reviews have already appeared in the USA.
In general, of course, it’s not worth judging the entire technology on a single product (in which, far more, not all 802.11ac features are realized), but you can make a first impression.
For those interested, I recommend reading the review as a whole, but I will consider one picture that interested me very much. Here the bundles "Buffalo router (802.11ac, 3x3: 3 MIMO, 80mHz channel) paired with another one" and "Linksys (802.11n, 3x3: 3 MIMO, 40mHz channel) with Intel Wireless-N6300" are compared.
When transmitting a single data stream, the implementation of 802.11ac in this router is of no interest: 802.11n reaches 110Mbps at 40Mhz (and this is not much), 802.11ac - 170Mbps at 80Mhz. In the same frequency range, you can put two 802.11n devices and get 220Mbps +. So real improvements in the Mbps / Mhz indicator are not visible. It is difficult to say why this happens: the detailed research methodology has not been published, and it is quite possible - just the features of the firmware. Theoretically, we should have seen at least a three-fold increase (2x channel + 256-QAM against 64-QAM).
')
But look what happens when the number of threads in a cell increases! 802.11n is “blown away” already on three streams, resting on the ceiling of 165Mbps (which is more like the truth and is very good for a consumer device, but 3x3: 3 MIMO may be more - the result from 165Mbps in Chariot is shown by dots from 2x2 MIMO), while the 802.11ac accelerates to seven! It is clear that the specific speed indicator falls on the stream, but still remains within reasonable limits: 438/7 = ~ 62Mbps of effective throughput (not datarate!) Even higher than 165/3 = 55Mbps, in 802.11n. The potential of the new technology, which squeezed out of the cell at almost three times the high speed (as expected) and provides greater capacity and scalability of the cell, is clearly visible.
Again, judging why this is happening (the advantages of the new technology are manifested only in multi-threaded mode) is not yet possible. I hope that soon the base of the tested devices will expand and it will be possible to draw any reasonable conclusions. For now - suggest versions in the comments!
In general, of course, it’s not worth judging the entire technology on a single product (in which, far more, not all 802.11ac features are realized), but you can make a first impression.
For those interested, I recommend reading the review as a whole, but I will consider one picture that interested me very much. Here the bundles "Buffalo router (802.11ac, 3x3: 3 MIMO, 80mHz channel) paired with another one" and "Linksys (802.11n, 3x3: 3 MIMO, 40mHz channel) with Intel Wireless-N6300" are compared.
When transmitting a single data stream, the implementation of 802.11ac in this router is of no interest: 802.11n reaches 110Mbps at 40Mhz (and this is not much), 802.11ac - 170Mbps at 80Mhz. In the same frequency range, you can put two 802.11n devices and get 220Mbps +. So real improvements in the Mbps / Mhz indicator are not visible. It is difficult to say why this happens: the detailed research methodology has not been published, and it is quite possible - just the features of the firmware. Theoretically, we should have seen at least a three-fold increase (2x channel + 256-QAM against 64-QAM).
')
But look what happens when the number of threads in a cell increases! 802.11n is “blown away” already on three streams, resting on the ceiling of 165Mbps (which is more like the truth and is very good for a consumer device, but 3x3: 3 MIMO may be more - the result from 165Mbps in Chariot is shown by dots from 2x2 MIMO), while the 802.11ac accelerates to seven! It is clear that the specific speed indicator falls on the stream, but still remains within reasonable limits: 438/7 = ~ 62Mbps of effective throughput (not datarate!) Even higher than 165/3 = 55Mbps, in 802.11n. The potential of the new technology, which squeezed out of the cell at almost three times the high speed (as expected) and provides greater capacity and scalability of the cell, is clearly visible.
Again, judging why this is happening (the advantages of the new technology are manifested only in multi-threaded mode) is not yet possible. I hope that soon the base of the tested devices will expand and it will be possible to draw any reasonable conclusions. For now - suggest versions in the comments!
Source: https://habr.com/ru/post/144050/
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