The Discovery Files: Power Nap

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.

Credit: NSF/Karson Productions

Audio Transcript:

(Sound effect: Smart phone ring) A Smarter Smart Phone.

(Sound effect: theme music) I'm Bob Karson with the discovery files--new advances in science and engineering from the National Science Foundation.

When your smart phone is waiting for your next hookup, it's on alert looking for messages and searching for clear communication channels. Did you know that it could be using as much power then as when it's sending and receiving messages? Researchers at the University of Michigan are working to make that idle time a lot less of a drain.

Meet "E-MILI," which stands for "Energy Minimizing Idle Listening." A way to have smart phones go into a slower, deeper mode of sleep, but still be ready to jump to full power when needed. The team believes that by using this new technology most smart phones could still keep one eye open for incoming messages while using as much as 44% less power.

E-MILI slows the clock in your Wi-Fi card to one-sixteenth of its normal frequency, that's easy, the hard part is to get the phone to recognize incoming messages while almost in a coma, so it can jolt back to full speed. Their solution was to get it to recognize just the headers of incoming messages. So they found a new way to encode the address header. To do this, it's going to require firmware modifications by the Wi-Fi chipset manufacturers, as well as getting the makers of smart phones onboard to install the chips in new phones. The project is in the proof-of-concept stage and could be reality soon.

Smart phones taking a real "power nap" -- would that make them "sleeper cells?[1]"

The Discovery Files" covers projects funded by the government's National Science Foundation. Federally sponsored research -- brought to you, by you! Learn more at nsf.gov or on our podcast.

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Notes:

[1] sleeper cells
It is used as a pun here. Sleeper cells originally means secret people who receive specialized training in their home countries and are then assigned to assimilate into another country's culture and society. These sleeper cells may spend years performing their regular duties while living deep undercover, then suddenly receive orders from their overseas handlers to either commit an act of terrorism or provide aid to those who will.