5G New Radio

1Introduction and Background

Mihai Enescu, and Karri Ranta-aho

Nokia Bell Labs, Finland

1.1 Why 5G?

It is perhaps a reasonable question to ask why we need 5G? Was in fact 4G/LTE and its evolution sufficient? Looking at LTE we note that indeed, we identify a good set of advanced technical components (speaking from the perspective of physical layer): it has multiple antennas scaling to the possibility to use massive MIMO (Multiple Input Multiple Output), it supports emerging connectivity techniques such as device-to-device, NB-IoT, Ultra Reliable and Low Latency Communications (URLLC). So why 5G? Every decade seems to bring a new wave of technology, this was the case with the arrival of 3G and 4G. From this basic perspective, the arrival of 5G strengthens this “rule.” Is there a need for 5G, especially given the fact that LTE and LTE-pro are capable of delivering high data rates and flexible technology? Yes, there is a need for 5G and there are a couple of reasons which we will elaborate next.

Like any evolving system, LTE has reached the limit of being a complicated design, its limitations coming from the fact that the basic design conceived a decade ago cannot be updated further in a simple way and cannot be kept easily compatible with the earlier equipment. The evolution of 3GPP generations has maintained the rule that all new devices are able to function in the older networks and vice versa without loss of functionality. As some of the components introduced at the very beginning ...