 3rd and 4th generation mobile communication systems (see Table 2.1). In early 2012, by taking into account 5G research activities around the world, ITU initiated studies on the development of "IMT for 2020 and beyond," called "IMT-2020." This section explains the vision of IMT-2020 and the development of IMT-2020 radio interface technologies by ITU in relation to the international standardization of 5G. 2.2.1 IMT Vision for 2020 and Beyond In September 2015, ITU published Recommendation ITU-R M.2083 [1], "IMT Vision - Framework and overall objectives of the future development of IMT for 2020 and beyond." This Recommendation was developed on the basis of a number of inputs by ITU members, taking into account the 5G research activities by industries, research organizations, and academia around the world at that time. The pre-standard research activities included under 5G-PPP projects like METIS 1 and 2 or 5G_NORMA in Europe and activities in Japan within 5GMF. One of the key messages described in the Recommendation is identification of the following three major usages scenarios in IMT-2020. Enhanced mobile broadband (eMBB). Supporting eMBB usage scenarios with improved performance and an increasingly seamless user experience compared to existing mobile broadband applications. Ultra-reliable and low latency communications (URLLC). Supporting stringent requirements for capabilities such as throughput, latency, and availability for those applications such as wireless control of industrial manufacturing or production processes, remote medical surgery, distribution automation in a smart grid, and transportation safety. Massive machine type communications (mMTC). Supporting a very large num- ber of connected devices typically transmitting a relatively low volume of non-delay-sensitive data. Recommendation ITU-R M.2083 also identifies a number of key capabilities of IMT-2020, such as peak data rate, user experienced data rate, spectrum efficiency, mobility, latency, connection density, network energy efficiency, and area