Motion detection enhances wireless network switching

In experiments on MIT’s campus-wide Wi-Fi network, the researchers discovered that, for users moving around, the protocols could often improve network throughput — the amount of information that devices could send and receive in a given period — by about 50 per cent.

The MIT researchers — graduate student Lenin Ravindranath, Prof Hari Balakrishnan, associate professor Sam Madden and postdoctoral associate Calvin Newport — used motion detection to improve distinct communications protocols.

One is said to govern the smartphone’s selection of the nearest transmitter.

‘Let’s say you get off at the train station and start walking toward your office,’ said Balakrishnan. ‘What happens today is that your phone immediately connects to the Wi-Fi access point with the strongest signal. But by the time it’s finished doing that, you’ve walked on, so the best access point has changed. And that keeps happening.’

By contrast, he added, the new protocol selects an access point on the basis of the user’s inferred trajectory.