Wireless LAN speeds of up to 1Gbps are coming down the pike â€“ but with the 802.11n standard only recently ratified and work only just beginning on its successor even conservative estimates suggest it could be three years before the 802.11ac standard sees the light of day.
Known officially as the ‘Very High Throughput < 6 GHz Task Group’ the IEEE 802.11ac working group has been pulled together to explore ways of delivering the next generation of wireless networking with speeds of 1Gbps promising to deliver short-range wireless data services running at speeds similar to those over the fastest wired networks. The standard is currently on a timeline for completion in 2012 but if this working group repeats the experience of the current 802.11n standard timelines may well slip into 2013 or beyond.
The current fastest WLAN standard 802.11n pushes data at speeds of up to 300Mbps using a novel MIMO (Multiple In-Multiple Out) configuration of multiple antennae working in sync. Just what form the 802.11ac standard might take however is still anybody’s guess â€“ even the members of the committee that’s exploring its technical feasibility.
Design goals for the new standard include backward compatibility with 802.11n and slower 802.11a networks; automatic detection of legacy networks; “training for wider channels”; low peak-to-average power ratio that ensures predictable usage of radiofrequency spectrum; and a receiver “design flow” close to that used in 802.11n networks.
Among the November task group meeting’s subjects was discussion about the structure of the ‘preamble’ which is used in wireless standards to help receivers detect the WLAN and synchronise themselves with the transmitter. The November meeting also saw the first meetings of ad-hoc groups discussing issues such as the structure of 802.11ac’s physical (PHY) layer media access control (MAC) MU-MIMO and coexistence with other wireless services.
Other topics recently discussed include packet structure error correction techniques quality of service mobile 802.11ac parameters and the many other protocols that will eventually combine to produce the next-generation standard.
The 802.11ac task group is chaired by Osama Aboul-Magd an Egyptian electrical engineering graduate who completed postgraduate education at the University of Toronto worked with Nortel Networks in Ottawa Canada and recently moved to Samsung Electronics.
Aboul-Magd has specialised in quality of service and traffic management features and helped create traffic management protocols for Asynchronous Transfer Mode (ATM) technologies in the late 1990s and more recently services for the Metro Ethernet Forum. He was also editor of the Ethernet Traffic Management Specification at the Metro Ethernet Forum.
Pictured right: Nortel’s Osama Aboul-Magd: steering us towards 1Gbps WLAN
Vice-chairs of the 802.11ac working committee are Menzo Wentink of Qualcomm and Joonsuk Kim of Broadcom two companies with a long pedigree in mobile and WLAN technologies. Other companies mentioned in various IEEE working papers include chipmakers Marvell Intel and Atheros as well as research groups at France Telecom’s Orange Labs and the Electronics and Telecommunications Research Institute of Korea.