As any mobile worker knows, tethering, where a user's smartphone provides an internet connection over 3G mobile networks, can be a real boon for those times where Wi-Fi coverage is too spotty.
But Wi-Fi tethering also eats into battery life, so while it can cut down on unproductive time, it's only a stop-gap measure. Now researchers from Microsoft have developed way to boost the power efficiency of Wi-Fi tethering.
The system, known as DozyAP, was designed by Yunxin Liu and colleagues at Microsoft Research in Beijing along with Hao Han of the College of William and Mary in Williamsburg, Virginia.
DozyAP works by putting smartphones into a low energy state when not downloading data while tethered. This so-called adaptive sleeping enables the system to minimise power consumption without impacting a user's ability to make use of their internet connection.
“Our sleep algorithm automatically adapts to the traffic pattern of applications and achieves a good balance between power saving and network performance,” the researchers wrote in their presentation paper.
To test the effectiveness of DozyAP, the researchers first analysed the impact of Wi-Fi tethering on a range of smartphones. Turning on tethering – but not actually actively using the internet connection – reduced the battery life of a Google Nexus One handset from 70 hours to just 5.2 hours.
They then tested the power consumption using a range of applications and tasks including downloading a 1MB file from a web server. Their experiments showed that using DozyAP was able to reduce power demands by nearly a third in some cases.
DozyAP is being shown off at the International Conference on Mobile Systems, Applications and Services in the Lake District this week.
27 Jun 2012
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