The standard, designated IEEE 802.11j, "Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications: 4.9 to 5 GHz Operation in Japan," takes advantage of spectrum and technology that has emerged since the original IEEE 802.11 standard was written in 1997. In August 2002, the Japanese Government published new rules to use 4.9 and 5 GHz bands in hot spot (indoor), fixed (outdoor), and nomadic (mobile) modes using Wireless LAN technology.
The amendment is targeted to the new Japan rules, and allows IEEE 802.11 networks to communicate and move to any new frequency, change the spectrum footprint to improve performance or user capacity, and communicate new rules and operating parameters to support both indoor and outdoor modes.
Depending on the manufacturer, IEEE 802.11 products may be upgraded to use IEEE 802.11j features to take advantage of these new capabilities.
"With existing spectrum used by more and more products, IEEE 802.11j was developed by leading international experts to allow WLAN products to take advantage of new frequencies and operating modes," said Stuart Kerry, chair of the IEEE 802.11 standards committee, in a statement.