the standards for all of today’s 3G
and 4G mobile systems, the International Telecommunication
Union (ITU) has established a new focus group to identify the
network standardisation requirements for 5G mobile telecoms
services for 2020 and beyond, to be hosted by ITU Standardisation
Sector (ITU-T, I). The ITU established a programme on
International Mobile Telecommunications (IMT) for 2020 and
beyond, which provides the framework for IMT-2020 research
and development worldwide. The timeline for the IMT-2020
are shown in Fig. 3.