Feeds

Boffins boost battery life with underclocked Wi-Fi

Removing the idle listening energy tax

Top 5 reasons to deploy VMware with Tegile

Scientists from the University of Michigan have devised a power management system that can greatly improve the lifespan of radio devices such as smartphones and laptops.

Engineering professor Kang Shin and doctoral student Xinyu Zhang have developed a technique for saving the battery life of Wi-Fi devices by clocking down the Wi-Fi radio system to 1/16th of its normal idling power output.

Dubbed "Energy-Minimizing Idle Listening" (E-MiLi), the technology works with current Wi-Fi technology (when the correct software is installed), and it can extend the life of a battery by up to 54 per cent, according to the boffins.

“We have a proof-of-concept implementation of E-MiLi based on software radios,” Xinyu Zhang tells The Register in an email exchange. In testing, the technique can boost smartphone battery life by 54 per cent.

Even in idle mode, standard Wi-Fi systems use more than two-thirds of the power consumed when fully operational, because the radio needs to be able to accept new data by examining incoming messages. The researchers call this "idle listening". E-MiLi allows the radio to largely power down, but it can reactivate by investigating header information on new data rather than examining all the data as a lump.

Specific tags in the header are needed and to make it work in existing kit, firmware and device drivers must be updated for the Wi-Fi card embedded in those mobile devices. The Wi-Fi cards also need to support downclocking at the hardware level.

"We came up with a clever idea," Shin says. "Usually, messages come with a header, and we thought the phone could be enabled to detect this, as you can recognize that someone is calling your name even if you're 90 per cent asleep."

Shin and Zhang present their paper on September 21 at the ACM International Conference on Mobile Computing and Networking in Las Vegas. They are now working on other power-saving techniques for Wi-Fi, specifically looking at regulating voltage directly.

“We have not completed experiments with voltage scaling. We expect much higher gain, because the power consumption is proportional to clock rate, and proportional to the square of voltage,” Xinyu Zhang says. ®

Internet Security Threat Report 2014

More from The Register

next story
Download alert: Nearly ALL top 100 Android, iOS paid apps hacked
Attack of the Clones? Yeah, but much, much scarier – report
Broadband sellers in the UK are UP TO no good, says Which?
Speedy network claims only apply to 10% of customers
Virgin Media struck dumb by NATIONWIDE packet loss balls-up
Turning it off and on again fixes glitch 12 HOURS LATER
Fujitsu CTO: We'll be 3D-printing tech execs in 15 years
Fleshy techie disses network neutrality, helmet-less motorcyclists
Facebook, working on Facebook at Work, works on Facebook. At Work
You don't want your cat or drunk pics at the office
Soz, web devs: Google snatches its Wallet off the table
Killing off web service in 3 months... but app-happy bonkers are fine
prev story

Whitepapers

Why cloud backup?
Combining the latest advancements in disk-based backup with secure, integrated, cloud technologies offer organizations fast and assured recovery of their critical enterprise data.
Forging a new future with identity relationship management
Learn about ForgeRock's next generation IRM platform and how it is designed to empower CEOS's and enterprises to engage with consumers.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.
Getting ahead of the compliance curve
Learn about new services that make it easy to discover and manage certificates across the enterprise and how to get ahead of the compliance curve.
Storage capacity and performance optimization at Mizuno USA
Mizuno USA turn to Tegile storage technology to solve both their SAN and backup issues.