RSS
Логотип
Баннер в шапке 1
Баннер в шапке 2
2010/05/10 21:16:38

IEEE 802.11n - Wi-Fi 4

802.11n - the standard for creation of wireless local area networks (WLAN). It is approved by the IEEE organization in September, 2009.

*IEEE 802.11ac - Wi-Fi 5 *IEEE 802.11ad (WiGig)

Content

The new standard offers higher data transfer rate and a bigger range in comparison with the Wi-fi standard which is the most distributed earlier — 802.11g which offers the maximum speed of data transmission of 54 Mbps at distance about 50 m indoors. The greatest possible data transfer rate 802.11n makes 300 Mbps, radius — in 10 times more in comparison with 802.11g. Main advantages of the new standard are provided due to MIMO technology (Multiple Input Multiple Output) when the signal is transmitted and accepted by several antennas at the same time.

Compatibility with draft versions

Practically all existing devices with support of 802.11 Draft-N can be updated to the final specification, this opportunity was put initially. Eventually, all future devices with support 802.11n will be compatible to the equipment released before, and having Draft-N marking.

Popularity of the standard

According to IEEE, networks 802.11n are already rather widespread. In September, 2009 day is on sale more than 1 million devices with support of this standard. The Intel corporation supports this standard in the mobile platform Intel Centrino.

According to forecasts of ABI Research, at the moment the most widespread sheaf applied in spot jotas is 802.11a/g. It makes 84% of all sales. It is expected that by 2012 sales of access points of standard 802.11n will bypass sales of devices of standard 802.11a/g and will make more than 60% of all deliveries. It is expected that by 2010 revenue from sale of devices of standard 802.11n will be twice higher, than the outdate standard.

History

The standard was in development since 2002. In 2006 the first draft version of the specification which allowed the companies to integrate support of the standard into notebooks was issued, to release the corresponding access points, routers and other equipment. However the draft status of the standard forced them to use a phrase "802.11 Draft-N" ("Draft option 802.11n). After an official approval of the standard the Draft prefix is not required any more.

In total part in development of the standard was taken by more than 400 specialists from the companies in production of semiconductors and network equipment, providers of services and educational institutions from more than 20 countries.