GUILDFORD, England — On the outskirts of this sleepy commuter town just south of London, plans are underway to build the fastest cellphone network in the world.

The work is being done at the University of Surrey, where a leafy campus is dotted with rundown Brutalist-style buildings. Here, researchers and some of the world’s biggest tech companies, including Samsung and Fujitsu, are collaborating to offer mobile Internet speeds more than 100 times faster than anything now available.

Their work on so-called fifth-generation, or 5G, wireless technology is set to be completed in early 2018 and would, for example, let students download entire movies to smartphones or tablets in less than five seconds, compared with as much as eight minutes with current fourth-generation, or 4G, technology. Companies also could connect millions of devices — including smartwatches and tiny sensors on home appliances — to the new cellphone network, and automakers could potentially test driverless cars around the suburban campus.

“A lot of the technology already works in a laboratory environment,” said Rahim Tafazolli, director of the university’s research center that oversees the 5G project, which includes almost 70 powerful radio antennas around the two-square-mile campus. “Now, we have to prove it works in real life.”