Beamsteering for mobile devices could cut power consumption in half

Dec 15, 2010 by Lisa Zyga weblog
A two-link network with two base stations and two mobile clients. Image credit: Hang Yu, et al.

( -- When turned on, today’s smartphones and other wireless devices radiate power in all directions while searching for communications nodes. But this omni-directionality can pose problems, such as limiting network capacity by causing interference among devices, as well as unnecessarily consuming power. However, if mobile devices could transmit power in a specific direction rather than all directions, researchers estimate that it could cut each device’s power consumption by half. Now, a team from Rice University has developed a beamsteering technique for smartphones, Netbooks, and e-book readers that transmits power in one direction only.

Although beamsteering has been previously used for base stations and other large applications, its bulky size and requirements have so far prevented its use for mobile devices. But Rice engineers Hang Yu, Lin Zhong, and Ashutosh Sabharwal have shown in a paper posted on arXiv that beamsteering technology can be made smaller and with minimal power requirements.

They show that employing beamsteering with four antennas can be easily integrated into a Kindle or iPad, and the power requirements are more than compensated by the device’s reduced transmit power. Simulations showed that the four-antenna technique reduces a mobile device’s overall power consumption by up to 55%, while a two-antenna technique could achieve a 40% reduction in power consumption.

As the researchers explained, taking advantage of beamsteering involves dealing with trade-offs. Many antennas require more overhead power and may cause interference with other devices, but also provide a more directed beam with lower device power consumption and thus high device efficiency. To help find the best compromise, the researchers developed software called BeamAdapt to be used on all mobile devices. BeamAdapt negotiates among mobile devices to determine the broadcast settings that provide the best transmission for everyone.

Although making this technology standard on all mobile devices might be prohibitive, it has great potential for significantly reducing the of increasingly popular . Even if the concept could become widespread, the engineers note that more research needs to be done before commercialization.

“Making mobile clients directional is a radical departure from existing and emerging wireless technologies,” they write in their study. “While we demonstrate the potential benefits from beamsteering clients in network capacity and client efficiency, much more research is needed in all layers of the network system in order to fully realize such potential.”

Explore further: A smart prosthetic knee with in-vivo diagnoses

More information: Hang Yu, et al. "Beamsteering on Mobile Devices: Network Capacity and Client Efficiency." arXiv:1012.2830v1 [cs.NI]
via: The Physics arXiv Blog

Related Stories

Qualcomm has 1 GHz mobile processor

Nov 09, 2005

Qualcomm plans to announce next year what it plans to do with a new mobile microprocessor that has a full gigahertz of capacity.

Gallium Nitride Power Transistor for Wireless Base Stations

Jan 12, 2005

According to JCN Network, Oki Electric has announced that it has started sample provisioning of it's Gallium Nitride High Electron Mobility Transistor (GaN-HEMT), a high frequency wave power transistor for wireless base stations. The new transistor, using gallium nitride ma ...

Recommended for you

A smart prosthetic knee with in-vivo diagnoses

Apr 22, 2014

The task was to develop intelligent prosthetic joints that, via sensors, are capable of detecting early failure long before a patient suffers. EPFL researchers have taken up the challenge.

Old tires become material for new and improved roads

Apr 22, 2014

( —Americans generate nearly 300 million scrap tires every year, according to the Environmental Protection Agency (EPA). Historically, these worn tires often end up in landfills or, when illegally ...

Students take clot-buster for a spin

Apr 21, 2014

( —In the hands of some Rice University senior engineering students, a fishing rod is more than what it seems. For them, it's a way to help destroy blood clots that threaten lives.

User comments : 8

Adjust slider to filter visible comments by rank

Display comments: newest first

not rated yet Dec 15, 2010
Thirty years ago I had a self-selective antenna on my boat for TV, which had about three dozen antennas on a printed circuit board. As the boat swung at anchor, it automatically selected, by monitoring strength of the incoming signal, which set of elements to use. A similar pc board in an iPad, etc, could select antenna elements. Not a big whoop. I imagine the new Australian outback internet system over TV channels has multiple antennas at the base station, and an aimed antenna at the customer. Much more efficient, not mobile, though. The base station could be programmed to transceive using the best antenna.
5 / 5 (2) Dec 15, 2010
I'm definitely getting a tinfoil hat now.
not rated yet Dec 15, 2010
Haha, I hope my phone doesn't decide to beamsteer it's 0.1-2Watt max microwave output through my brain.. But either way I doubt I would notice.
not rated yet Dec 16, 2010

As opposed to just radiating power in all directions?..
not rated yet Dec 19, 2010
As opposed to just radiating power in all directions?..
Yeah, well at least the battery will last longer. Hopefully making it directional will also lower the transmit power, since omnidirectional max output is 2Watts the same power density (W/m^2) could be achieved with less if it's directional. I guess the maximum transmit power would be lowered for these phones.
not rated yet Dec 26, 2010
Haha, I hope my phone doesn't decide to beamsteer it's 0.1-2Watt max microwave output through my brain.. But either way I doubt I would notice.

You have a brain?!
Just KIDDING!!! Merry Christmas
not rated yet Dec 26, 2010
As opposed to just radiating power in all directions?..

Or powering radiators in all directions...
not rated yet Dec 27, 2010
Back damn you troll, back!

More news stories

Amazon Prime wins streaming deal with HBO

Amazon scored a deal Wednesday to distribute old shows from premium cable TV channel HBO to its monthly Prime subscribers, landing a blow on rival Netflix in the streaming video battle.

Is nuclear power the only way to avoid geoengineering?

"I think one can argue that if we were to follow a strong nuclear energy pathway—as well as doing everything else that we can—then we can solve the climate problem without doing geoengineering." So says Tom Wigley, one ...

Robot scouts rooms people can't enter

( —Firefighters, police officers and military personnel are often required to enter rooms with little information about what dangers might lie behind the door. A group of engineering students at ...

Cyber buddy is better than 'no buddy'

A Michigan State University researcher is looking to give exercise enthusiasts the extra nudge they need during a workout, and her latest research shows that a cyber buddy can help.