Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Smartphone battery life could dramatically improve with new invention

16.09.2011
A new "subconscious mode" for smartphones and other WiFi-enabled mobile devices could extend battery life by as much as 54 percent for users on the busiest networks.

University of Michigan computer science and engineering professor Kang Shin and doctoral student Xinyu Zhang will present their new power management approach Sept. 21 at the ACM International Conference on Mobile Computing and Networking in Las Vegas. The approach is still in the proof-of-concept stage and is not yet commercially available.

Even when smartphones are in power-saving modes and not actively sending or receiving messages, they are still on alert for incoming information and they're searching for a clear communication channel. The researchers have found that this kind of energy-taxing "idle listening" is occurring during a large portion of the time phones spend in power-saving mode—as much as 80 percent on busy networks. Their new approach could make smartphones perform this idle listening more efficiently. It's called E-MiLi, which stands for Energy-Minimizing Idle Listening.

To find out how much time phones spend keeping one ear open, Shin and Zhang conducted an extensive trace-based analysis of real WiFi networks. They discovered that, depending on the amount of traffic in the network, devices in power-saving modes spend 60 to 80 percent of their time in idle listening. In previous work, they demonstrated that phones in idle listening mode expend roughly the same amount of power as they do when they're fully awake.

"My phone isn't sending or receiving anything right now," Shin said, lifting his power-skinned iPhone, "but it's listening to see if data is coming in so I can receive it right away. This idle listening often consumes as much power as actively sending and receiving messages all day."

Here's how E-MiLi works: It slows down the WiFi card's clock by up to 1/16 its normal frequency, but jolts it back to full speed when the phone notices information coming in. It's well known that you can slow a device's clock to save energy. The hard part, Shin said, was getting the phone to recognize an incoming message while it was in this slower mode.

"We came up with a clever idea," Shin said. "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 percent asleep."

When used with power-saving mode, the researchers found that E-MiLi is capable of reducing energy consumption by around 44 percent for 92 percent of mobile devices in real-world wireless networks.

In addition to new processor-slowing software on smartphones, E-MiLi requires new firmware for phones and computers that would be sending messages. They need the ability to encode the message header—the recipient's address—in a new and detectable way. The researchers have created such firmware, but in order for E-MiLi use to become widespread, WiFi chipset manufacturers would have to adopt these firmware modifications and then companies that make smartphones and computers would have to incorporate the new chips into their products.

Shin points out that E-MiLi is compatible with today's models, so messages sent with future devices that use E-MiLi's encoding would still be received as usual on smartphones without E-MiLi. E-MiLi can also be used with other wireless communication protocols that require idle listening, such as ZigBee.

Shin is the Kevin and Nancy O'Connor Professor of Computer Science. This research was funded by the National Science Foundation. The paper is titled "E-MiLi: Energy-Minimizing Idle Listening in Wireless Networks." The university is pursuing patent protection for the intellectual property, and is seeking commercialization partners to help bring the technology to market.

Nicole Casal Moore | EurekAlert!
Further information:
http://www.umich.edu

More articles from Power and Electrical Engineering:

nachricht Energy-efficient spin current can be controlled by magnetic field and temperature
17.08.2018 | Johannes Gutenberg-Universität Mainz

nachricht Scientists create biodegradable, paper-based biobatteries
08.08.2018 | Binghamton University

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Color effects from transparent 3D-printed nanostructures

New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference

Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

LaserForum 2018 deals with 3D production of components

17.08.2018 | Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

 
Latest News

Smallest transistor worldwide switches current with a single atom in solid electrolyte

17.08.2018 | Physics and Astronomy

Robots as Tools and Partners in Rehabilitation

17.08.2018 | Information Technology

Climate Impact Research in Hannover: Small Plants against Large Waves

17.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>