The first generation, retroactively called 1G, was a . In contrast, 2G phones transmitted voice and data digitally. Subsequent generations, and , made technical improvements that brought data rates up from 200kbit/s to . With 2020 approaching, 5G is expected to transmit 1Gbit/s — and perhaps .
Being able to send and receive that much data so quickly opens new opportunities for augmented and virtual reality systems, as well as automation.
For instance, , road signs, traffic signals, guard rails and other elements human drivers simply see. That would require an additional technical leap — reducing what is called “latency”, or the and when it’s received, to one millisecond. (If a network’s data rate is how wide a garden hose is, latency is how long it takes from the moment the tap is turned on until water comes out the end.)
Achieving high data rates with low latency requires a number of technical changes, including sending data and designing arrays of antennas to reduce interference between . Together these add up to a 5G network with — each of which is physically smaller than a current cellular tower and placed much more closely together. 5G base stations could be placed , rather than the every 1km to 5km needed for 4G.
In addition, 5G systems offer the possibility of providing reliable connections to massive numbers of wireless devices simultaneously. This could enable a huge expansion of the number of “Internet of things” devices in use, monitoring nutrients in soil for farmers, package locations for shipping companies and vital signs for hospital patients, for instance.
are in some US cities. The Tokyo Olympics in 2020 are supposed to present the very can offer. Between now and then — and even beyond — companies rolling out 5G networks will deploy a new technology while it’s still evolving, as they did with earlier generations.
· Written by Jan Rabaey, professor of electrical engineering and computer science, University of California, Berkeley