The Wi-Fi alliance has been working on the specification for the Wi-Fi 802.11 AC wireless standard, announcing Wave 2 of the spec to improve transmission speeds to multiple users in a world where more devices are using wireless.
The basis of the update is improved multi-user transmission, or Multi-user Multiple Input Multiple Output (MU-MIMO). This allows for transmission of data to multiple devices at once, rather than one at a time in previous MIMO implementations. The new Wi-Fi AC spec also increases the maximum channel bandwidth from 80 MHz channels to 160 MHz channels which potentially doubles the transmission speeds.
As well as increasing speeds and the amount of users receiving data, the improved Wi-Fi AC spec adds an additional spatial stream to the three existing streams. There’s room to move in future with Wi-Fi AC capable of using more streams but at this stage, Wave 2 only supports four in total.
Finally, the new spec also improves 5GHz support. The new 5GHz support, the Wi-Fi Alliance says that the additional channels makes ‘more efficient use of available spectrum and reduces interference and congestion by minimizing the number of networks operating on overlapping channels’.
Source : ausdroid.net