Wednesday, July 13, 2011

WiGig and Beamforming - 7Gbps Wireless

Casey Johnston on a promising wireless technology. Great potential, but some limitations need to be addressed for this to anything but a niche technology.

Beamforming your data: how WiGig will offer 7Gbps speeds:
The Wireless Gigabit Alliance recently announced that it has published the certification-ready 1.1 specification of its wireless system

...

WiGig is a specification for hardware that uses 60GHz frequencies to transmit up to 7 gigabits of data per second over the air; for comparison, 802.11n WiFi tops out at a few hundred megabits per second.

...

The WiGig Alliance recently pegged the launch of capable devices for the first half of 2012.

WiGig is sufficiently advanced to have its own IEEE 802.11 standard, coded as 802.11ad. Using it at the time of release will require some new hardware both to send and receive signal, similar to when 5GHz started to make its way onto the market. Unlike 5GHz WiFi, though, WiGig's design includes methods for avoiding the decay problems that higher-frequency transmissions usually have.

To overcome signal decay, WiGig uses a process called adaptive beamforming (it's not the first or only system to do so, but is heavily reliant on it). With a combination of physical antennas on the devices and algorithms to tune the signal, WiGig devices effectively shoot their signals back and forth at each other in a narrow, targeted beam.


There are problems though, particularly with mobility, range and obstructions.
we're not sure we'll be able to stroll around holding our WiGig-capable devices and maintain the 60GHz signal. Still, the specifications say the equipment must be able to fall back on 2.4GHz and 5GHz signals in the event that it loses the higher-speed connection.

Mobility isn't the only downfall of WiGig, though—according to the WiGig Alliance, the beamforming of compliant equipment needs to be within line-of-sight of receiving devices in order to work well. Even a person stepping between two communicating devices can break the signal, though according to a whitepaper by the group, WiGig-compliant equipment can bounce beams off walls and ceilings in order to reach between devices.

According to the specifications, devices can work over distances "beyond 10 meters," but it seems walls and ceilings will be an even bigger obstacle for 60GHz WiFi than they already are for 2.4GHz and 5GHz signals.

No comments:

LinkWithin

Related Posts Plugin for WordPress, Blogger...