Speedy 802.11ac Wi-Fi set for fast, wide rollout
Mobile carriers embracing Wi-Fi is one of the sub-themes of Mobile World Congress. And the particular flavor of Wi-Fi that’s generating buzz here is 802.11ac, which promises to boost handset throughput to over 300Mbps.
What MWC is driving home is how close 11ac products are to appearing. For clients to achieve those speeds, they have to be talking to access points or hotspots or even so-called “small cells” (compact cellular base stations) that are also outfitted with 11ac radio chips.
Broadcom executives at MWC confirmed today that the chipmaker is “beyond the sampling phase and even in a preproduction phase,” according to Michael Hurlston, the company’s senior vice president for wireless LAN, for its two-stream and three-stream 11ac chips. 11ac like 11n uses multiple data streams paired with multiple sending and receiving antennas to achieve high data throughput.
Hurlston said he expects finished OEM products, almost certainly access points, routers and the like, to be on sale from Broadcom’s customers by mid-2012. Although the chipmaker hasn’t announced design wins, Hurlston pointed out that the 11ac roadmap announced last month at CES was publicly endorsed by 14 equipment vendors and network providers.
In the booth, Broadcom was running one-, two- and three-stream 11ac radios. The single-stream radio, the type that would be integrated into a smartphone, was delivering usable throughput ranging between 300Mbps and 370Mbps (compared to the underlying PHY rate of 450Mbps), orders of magnitude greater than the 30Mbps-50Mbps, or slightly more, that single-stream 11n can deliver for phones today.
There is a widespread expectation that the additional premium that equipment makers and ultimately end users will have to pay for this improvement is comparatively low. Hurlston estimated that the premium for its 11ac products will be range from 1.2 to 1.5 times initially. “We exceeded our expectations for that [i.e., for keeping it low],” he said. If the takeup is as fast as many expect, that will rapidly decline.
The three-stream products from Broadcom and rivals like Qualcomm and Atheros will support throughput of just over 1 gigabit initially.
Qualcomm, with the Wi-Fi expertise and technology from its Atheros acquisition, confirmed it will start sampling its 11ac product family sometime in 2012 Q2, according to David Favreau, vice president of product management.
A lot of Qualcomm’s development effort has also involved creating integrated communications processors, marrying Wi-Fi with Bluetooth and other radios, and then tying the result closely to its Snapdragon applications processor, which powers a wide range of smartphones today.
Qualcomm’s booth here showed its single-stream 11ac radio, mounted in smartphone prototypes, running in the 220Mbps range, peaking at one point to 247Mbps, in a surrounding Wi-Fi environment, inside MWC’s cavernous Hall 8, that Favreau described as “challenging.”
Qualcomm’s timeline is less aggressive than Broadcom’s. Favreau says he’s working with equipment makers, for everything from phones and laptop dongles to access points, to release final products in early 2013, a time frame chosen to coincide with the ramp-up of the Wi-Fi Alliance’s 11ac certification program. The reason, he says, is to ensure that most of the first 11ac implementations are fully interoperable, avoiding the stumbles that occurred with early releases of the still-in-development 802.11n products a couple of years ago.
Both companies say the extra power won’t take extra electrical power, a key issue for battery-operated mobile devices. Part of the reason is proprietary power management wizardry, but part of the reason is simply the much higher 11ac throughput. “We run apps much faster, and get back to a low-power ‘sleet state’ [for the radio] much faster, and spend more time in sleep state,” Favreau said.
“We think 11ac will be adopted much faster than 11n was,” he said. One reason for that is the expected fast adoption of 11ac in a wide range of client devices, including the fast growing markets for smartphones, tablets and increasingly for consumer electronics like digital cameras and flat panels.
Another reason, at least for Qualcomm’s network gear builders, is what Favreau called CPU offload. “OEMs can reuse their existing network processors, and just add in our new high-end 11ac product,” he said.