Final preparations to begin testing products for compliance with the Wi-Fi5 standard, which supports data transmission at rates as high as 54Mbps, are currently underway at Agilent Interoperability Certification Labs, which handles the testing for WECA.
The Agilent Technologies labs, along with four others around the globe, are expected to complete installation of test-bed equipment in August or September and then begin accepting products for a certification process that takes around one week.
Once products pass, WECA issues manufacturers with certification and allows them to display the Wi-Fi5 logo on the product. Presence of the mark should mean interoperability between products from different vendors and users being spared the headache of 802.11a boxes that refuse to talk to each other, just as the WECA-issued Wi-Fi logo does for 802.11b products.
While certification of 802.11a products has yet to begin, interoperability testing is already underway and initial results are promising, said one vendor involved in the work.
"It was much, much better than I expected," Trent Carter, a systems manager with wireless LAN chipset maker Intersil, said. "Interoperability of all significant features was flawless. There were a few small problems, which will require fixing, but nothing at the level that users would notice," he said of tests that occurred at the University of New Hampshire earlier this year.
With certification about to begin, marketing of Wi-Fi5 equipment is expected to increase as the standard gathers momentum. However, as with many technologies, there could be a price to pay for early adoption.
In the US, the system uses three chunks of 100MHz of unlicensed spectrum in the 5GHz band. The low and middle bands are next to each other, from 5.15GHz to 5.25GHz and then to 5.35GHz. The upper band runs from 5.72GHz to 5.82GHz, and that represents a headache for hardware makers, Intersil's Trent said.
"Nobody has a radio that covers all three bands, no matter what they say," he said. "It is very difficult to get a radio to cover such a wide spectrum and so everybody is concentrating on the lower two bands."
Much of the 802.11a equipment on the market now operates in only the low and middle bands, which means users have a maximum of eight overlapping channels to play with rather than 12. In reality, the number of channels available could be even less, depending on how susceptible the applications running on the network are to errors.
"The channels overlap and so this will introduce packet errors," said Trent. "If you are looking for acceptable error rates below 10%, that could mean only six non-overlapping channels are available (in the three bands)."
This doesn't mean the system won't work, he said, but it does mean manufacturers will have to spend more time designing their radio circuits and users will have to be more careful about access point placement to cut down on cross-channel interference.
The first chipsets that feature support for all three US-licensed bands are expected later this year. Major chipset maker Atheros Communications is sampling its wideband chipset now and expects to begin mass production sometime in the fourth quarter of this year, Alan Yang, Taiwan country manager for the company, said at the Networld + Interop show.
Beyond the spectrum issues for chip makers in the US market, the picture is further complicated by a lack of common regulatory environments around the world. Unlike the 2.4GHz spectrum, which is used for 802.11b and is almost universally available for unlicensed use, the 5GHz band is not as free.
In Japan, one of the few countries where space has been cleared, the upper band is not available and a new chunk of spectrum from 4.9GHz has been opened up. In Europe, the space has been reserved for HiperLAN/2 although that technology's future is currently in question and 802.11a equipment makers have challenged regulators by moving to begin selling equipment in selected markets. All of this makes a world-band card, such as is common for 802.11b, less likely to appear in the short term until a more common environment prevails worldwide.