Nokia Networks and Japanese carrier NTT DoCoMo are testing networks using extremely high frequencies that may someday deliver multi-gigabit speed to mobile devices.
The companies’ technology trial is using 70GHz radios that today are about the size of a carry-on suitcase. Eventually, the technology will shrink down to about 5 millimeters across to fit in a mobile device.
So-called millimeter-wave radios can pack a lot of data into a narrow beam, and the frequencies they’re designed to use aren’t in high demand these days. That’s why Nokia and other vendors see this technology as a key part of the future 5G mobile standard coming in 2020.
The trick is pointing that beam at a mobile device, but Nokia and others say they’re working that out. In its booth at Mobile World Congress, Nokia demonstrated a 70GHz base station tracking a moving radio — at pedestrian speed — representing a mobile phone. The cell used a lens to focus its signal. As the base station locked on to the moving box, a gauge showed the connection between them jumping up to 2Gbps (bits per second).
The two components were only a few meters apart in a glass booth, but the idea is eventually to set up millimeter-wave cells on street lamps, about one per block. One cell will be able to track and communicate with multiple mobile devices at once, shifting from one to another in a microsecond, said Mark Cudak, a principal research specialist at Nokia.
Millimeter-wave technology is part of a broad industry effort to take advantage of frequencies above 6GHz, which mobile networks have mostly left alone until now. Ericsson, AT&T and Intel are also interested in this field, and the U.S. Federal Communications Commission recently asked for input on mobile uses for bands between 24GHz and 72GHz.
High frequencies could be a boon to the Internet of Things, where various applications such as self-driving cars and remote medical care will drive demand for both more bandwidth and lower latency, said Phil Twist, vice president of portfolio marketing. The IoT devices will grow in number much faster than smartphones over the next several years, he said. Carriers will need a lot more spectrum to serve that growing field.
The 70GHz band where Nokia and DoCoMo’s trial is taking place has 10GHz of spectrum that could be licensed to carriers in some places and may be a good bet for finding a standard band that regulators agree on around the world, Twist said. The demonstration at MWC is using just 1GHz of the band but future radios could use 2GHz and carry two streams of data. The goal is to eventually get peak speeds of 10Gbps.