We are constantly connected because we have to get our emails on a real time basis, tweet often, and because Facebook is where our social life is. While phones have become smart enough to handle all this, more often than not their batteries are unable to cope.
There is substantial congestion in networks these days. Congestion works like a traffic jam, wherein vehicles waste fuel without moving an inch. In vehicles there is the ‘start stop system’, also called Micro Hybrid by Mahindra, which switches off the car when it is not moving and switches it on when you are ready to go, without your having to touch a thing. This saves a lot of fuel.
Scientific American has reported that a Duke University researcher, Justin Manweiler, a computer science graduate student at Duke’s Pratt School of Engineering, has developed software he calls SleepWell, which works on similar principles.
Mobile devices today waste a lot of energy searching for the WiFi signal, and then staying connected while overtaxed wireless networks ferry data to and from them. SleepWell allows a mobile device to slip into power-saving mode while it is awaiting its turn to connect.
This is specially useful when people flock to coffee shops lured by free WiFi networks. Manweiler likens the competition for WiFi to big-city traffic. When workers leave their offices en masse at the end of the day, they clog up the roads and rail lines. If these workers staggered the times they left, the transit systems would be less crowded, and it would take less time to get home. Similarly, if mobile devices took their turn accessing WiFi access points, data would move faster and these devices would use less energy.
Sleepwell is designed to double the battery life of internet-connected devices increasingly called on to upload and download music, images and video via WiFi.
SleepWell is installed on devices that create a WiFi network infrastructure, including WiFi routers and access points (hotspot feature in Android 2.2). As such, it is designed so that any mobile device—whether it uses Apple OS X, Google Android, Windows or some other platform—can take advantage of it.
SleepWell software differs from the “sleep” mode already available in many devices. An operating system’s version of sleep is designed to work over long time scales—minutes, hours or days. “SleepWell is enabling short ‘sleep’ periods multiple times per second. These sleep periods are so short, the user remains unaware and unaffected.”
During testing, Manweiler found that SleepWell could double the battery life of mobile phones. “We ran lots of live experiments using real off-the-shelf smartphones, mostly Google Android phones,” he says. “We tested with a variety of use cases, including the user watching a movie trailer on YouTube, playing music on Pandora and Last.FM internet radio, and downloading a large file from the web.”
The extent to which battery life would be prolonged of course varies depending on the situation. Still, Manweiler hopes the brief naps that SleepWell affords mobile devices will add up to significant energy conservation when WiFi networks are in high demand.