The fast, high-capacity Wi-Fi that users have been enjoying for a few years in laptops is now due to hit smartphones and tablets in a big way, with two major Wi-Fi chip makers announcing products that use IEEE 802.11n with multiple antennas.
So-called MIMO (multiple-in, multiple-out) technology is one of the key capabilities of 802.11n, the most recent major wireless LAN standard. Access points and client devices based on 11n can exchange multiple streams of data over multiple antennas, making network capacity increase by double or more, depending on how many radios and antennas they have. But this capability so far has been limited mainly to PCs and some home electronics.
On Thursday, Atheros Communications and Marvell Technologies announced MIMO chips for mobile clients. These chips can be deployed in smartphones or other handheld devices to strongly boost the speeds that users enjoy, with little or no additional battery drain, according to the companies. Both companies will showcase these chips at the Mobile World Congress show in Barcelona next week.
To enjoy the full speed boost of MIMO, both the client and the access point need to have the capability. But the new silicon could be good news for mobile operators with heavily taxed cellular data networks, as well as for subscribers using those networks. Some carriers already use Wi-Fi hotspots extensively in order to give users higher speeds in densely crowded areas. Additional capacity on Wi-Fi should translate into speeds higher than cellular for some users, or an alternative path to the Internet or multimedia applications for people in very crowded areas.
On Thursday, Atheros announced the AR6004, an SOC (system on a chip) with 2x2 MIMO, allowing for two ingoing and two outgoing data streams. The AR6004 can use both the 2.4GHz and the 5GHz radio bands and is capable of real-world speeds as high as 170M bps (bits per second). The company has been able to build MIMO into the AR6004 such that the new chip consumes only 15 percent more power than the current AR6003, which offers only 85M bps, according to Tim Peters, senior director of mobile communications at Atheros.
The Atheros chip is intended for both high-end smartphones and tablets. It will be available in sample quantities by the end of this quarter and in commercial quantities in the first quarter of next year, Peters said.
Also on Thursday, Marvell introduced the Avastar 88W8797, another 11n dual-band chip with 2x2 MIMO capability. The chip is capable of data rates as high as 300M bps, according to Marvell, and includes Bluetooth capability. It is designed for smartphones and tablets as well as sensor devices for health monitoring and home automation. It is available now in sample quantities.
In especially crowded locations, 2x2 MIMO will help mobile operators absorb the ongoing explosion in mobile data use more economically, said Farpoint Group analyst Craig Mathias. The two-stream technology has twice the capacity of one-stream Wi-Fi, so carriers can do a better job of reaching subscribers with the same number of installations.
Despite the many variables involved in wireless performance, including distance and competition from other nearby subscribers, the added stream will make a difference, Mathias said. The added capacity won't ensure faster downloads every time, but it makes it more likely that many users in the same area will be able to use network-hungry services such as video.
"They're never going to guarantee throughput, but they have to provide capacity," Mathias said.