Wi-Fi Goes International
December 06, 2004
New standards for use of 4.9GHz Wi-Fi in Japan and preventing disruption of U.K. radar standards mark a time for WLANs to become less U.S.-oriented.
Wi-Fi, often accused of being dominated by U.S. thinking, is now going global as new wireless standards adapt to the needs of Japan and Europe. They give the original 802.11 standard a facelift, updating the technology in the face of new concerns overseas.
Atheros Communications recently announced it would support the IEEE's newly-ratified 802.11j standard. Born from rules published in 2002 by the Japanese government, 802.11j standardizes custom chipsets that can use both the 4.9 and 5 GHz radio bands.
The rules set forth by the Japanese government open the two bands to indoor, outdoor and mobile WLAN applications. The regulations also require companies to adjust the width of those channels.
Atheros has been selling custom-designed chipsets in the Japanese market for some time. The new standard means customers of the chipmaker can make that gear 802.11j-compliant simply by upgrading firmware.
Think of the radio spectrum as an FM tuner, suggests Sheung Li, chair of the IEEE 802.11j Task Group. The new standard allows wireless equipment to reach some channels not available before.
The new standard also takes into account crowded radio airwaves. "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," according to Stuart Kerry, IEEE 802.11 Working Group standards committee chairman.
While its formal title is "Wireless LAN Media Access Control (MAC) and Physical Layer (PHY) Specifications: 4.9 —5 GHz Operation in Japan," 802.11j is often referred to as the 'Japan Standard.' That's something the IEEE would like to stop."11j doesn't stand for Japan," says Li. The task group chairman explains 'j' was simply the next available letter in the IEEE's 802.11 alphabet after the 802.11i security amendment.
Li, who is also an Atheros Product Line Manager, emphasizes the importance of adapting Wi-Fi to the needs of Japan. The market for Wi-Fi products in Japan is the equivalent of 60 to 75 percent of the U.S. Wi-Fi market.
Although 802.11j targets the Japanese Wi-Fi market, the new standard will also assist with an increasing demand for Wi-Fi products operating in the 4.9 GHz band.
"In the U.S., the 4.9 GHz band is being adopted for public safety and homeland security communications networks," according to an Atheros statement.
Japan is not alone in garnering new attention from the IEEE. The standards organization has also adopted 802.11h as a Wi-Fi amendment responding to Europe's need for 802.11a signals that don't run roughshod over military radar.
The 802.11h standard permits Wi-Fi to operate by changing how it transmits. Rather than 802.11a blasting recipients with a steady power level, 802.11h uses just enough power to be heard by users while also dynamically changing radio frequencies to avoid trampling radar signals.
NewLogic is offering support for 802.11h in its WiLD WLAN product.
From 802.11a to 802.11g, Wi-Fi standards have been predominantly shaped by U.S. influences. While 4.9 GHz has not reached the scale of 802.11g, for instance, the new band means Wi-Fi takes on a more global appearance. "The rest of the world is leading" in 4.9GHz activity, says Li.