There are few things more frustrating than trying to use your phone on a crowded network. With phone usage growing faster than wireless spectrum, we all are fighting over smaller and smaller bits of bandwidth.
Researchers from the Computer Science and Artificial Intelligence Lab (CSAIL) at the Massachusetts Institute of Technology, Cambridge, Mass., say that they have a possible solution. In a paper, a team led by Dina Katabi, professor of electrical engineering and computer science and director of the Wireless Center, demonstrates a system called MegaMIMO 2.0 that can transfer wireless data more than three times faster than existing systems while also doubling the range of the signal.
The system’s key insight is to coordinate multiple access points at the same time, on the same frequency, without creating interference. This means that MegaMIMO 2.0 dramatically could improve the speed and strength of wireless networks, particularly at high-usage events like concerts, conventions, and sporting events.
“In today’s wireless world, you can’t solve spectrum crunch by throwing more transmitters at the problem, because they will all still be interfering with one another,” says lead author and Ph.D. Student Ezzeldin Hamed. “The answer is to have all those access points work with each other simultaneously to efficiently use the available spectrum.”
The main reason that your smartphone works so speedily is multiple-input multiple-output (MIMO), which means that it uses several transmitters and receivers at the same time. Radio waves bounce off surfaces and therefore arrive at the receivers at slightly different times; devices with multiple receivers, then, are able to combine the various streams to transmit data much faster.
For example, a router with three antennas works twice as fast as one with two antennas but, in a world of limited bandwidth, these speeds still are not as fast as they could be, and so in recent years researchers have been looking for the wireless industry’s Holy Grail: being able to coordinate several routers at once so that they can triangulate the data even faster and more consistently.
“The problem is that, just like how two radio stations can’t play music over the same frequency at the same time, multiple routers cannot transfer data on the same chunk of spectrum without creating major interference that muddies the signal,” notes Hariharan Rahul, an alumnus of Katabi’s lab and visiting researcher with the group.
The technology also can be applied to cellular networks, meaning that it could solve similar congestion issues for people who actually want to use their phones to make calls. He indicates that the team plans to expand MegaMIMO 2.0 to be able to coordinate dozens of routers at once, which would allow for even faster data-transfer speeds.
Copyright Society for Advancement of Education Aug 2017.