"Out of the gate, the increases in performance over 11n will not be tremendously impressive. The second wave--which will require a hardware refresh--gets far more interesting... First-generation 802.11ac products will achieve up to 1.3 Gbps through the use of three spatial streams, 80-MHz-wide channels (double the largest 40 MHz channel width with 802.11n), and use of better hardware components that allow higher levels of modulation and encoding (up to 256-QAM). Whether we will actually see 802.11ac products capable of 6.9 Gbps is dependent on hardware enhancements on both the access point and client that are not certain.""
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