Major Enhancements

  • 5GHz only
  • 80MHz / 160MHz (80×2 non contiguous, or 1×160) channels. Larger channels also have reducted pilot overhead (20MHz = 7%, 160MHz = 3%)
  • 256QAM (denser constellation). 64QAM to 256QAM is roughly +25Mbps [vs 64QAM] per 20MHz, but requires pinpoint ‘accuracy’ = short range between AP and client. EVM (Error Vector Magnitude) gives insight into the evident degree of inaccuracy
  • Clear Channel Assessment (CCA / Shared Airtime) on both primary and secondary channels via RTS/CTS bandwidth negotiation
  • Standardised Beamforming (Null Data Packet) - Channel Sounding > Feedback Matrix > Steering Matrix
  • MU-MIMO facilitates up to to four distinct downstream transmits (eight total streams, eg 4×2), moving towards a WiFi ‘switch’ [vs SU-MIMO ‘hub’]
  • GCMP (CCMP replacement, enables processor embedded parallel encryption)
  • MAC updates (HT > VHT, MPDU > A-MPDU)

Phases

  1. 1.3Gbps (SU-MIMO [1×4 max], 80MHz, 256QAM)
  2. 2.6Gbps (MU-MIMO [2×4 max], 160MHz)
  3. 4+Gbps
  4. EU and AU would benefit from mimicing US FCC’s recent spectrum rulings which free up many 5GHz channels specifically for 802.11ac use
  5. 802.11ad is a high speed, high frequency (>6GHz), low range spec with very different use cases (wireless docking, cable replacement etc)