IEEE 802.11ac standard amendment introduces gigabit data rates to 802.11 wireless networking. The maximum data rates with 802.11ac will be ten times faster than with the 802.11n standard, reaching almost 7 Gbps. These data rates will significantly enhance Wi-Fi usages such as wireless display and sync-and-go. This tutorial provides a comprehensive overview of the technology in the p802.11ac draft standard amendment.
We begin with an overview of the applications, environments, channel models, use cases, and usage models developed by the study group and task group that provided the framework for proposal development. We continue with the technical description of the draft standard with a detailed discussion of the key throughput enhancing features: wider bandwidth channels and multi-user, multiple-input, multiple-output (MU-MIMO).
Further throughput enhancements in the PHY include 256 QAM and up to eight spatial streams. In the MAC, this includes enhancements to the aggregation. Additional important topics include the new PHY preamble, auto-preamble detection, non-contiguous channelization, and modifications to LDPC and STBC. In the MAC topics such as coexistence mechanisms for wider channels and enhancements to the clear channel assessment mechanism will be covered. Transmit beamforming in 802.11ac will also be reviewed to highlight the improvements over 802.11n transmit beamforming.
Dr. Eldad Perahia is Intel Corporation’s lead in IEEE 802.11ac. He has been actively involved in the 802.11ac task group since its inception. Eldad is the 802.11ac Coexistence Ad Hoc co-chair. Eldad is also the 802.11ad (60 GHz) chair. Prior to that, he was the chair of the 802.11 Very High Throughput Study Group that launched 802.11ac and 802.11ad. Eldad was also the 802.11n Coexistence Ad Hoc chair. He has twenty patents, and numerous papers and patent filings in various areas of wireless including satellite communications, cellular, WLAN, millimeter wave technology, and radar. Eldad has a Ph.D. from the University of California, Los Angeles in electrical engineering specializing in digital radio.
Robert Stacey is Apple’s lead in IEEE 802.11ac. He is Technical Editor for the 802.11ac amendment, co-chair of the MU-MIMO ad-hoc in the 802.11ac task group and an active participant in various 802.11 task groups. Robert has numerous patents in the field of wireless communications. He has a MSEE from University of the Witwatersrand, South Africa.
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Gigabit Wireless LAN: Enhancements in IEEE 802.11ac