, supported by the need for LTE-Advanced evolution in parallel. A consensus emerged that there should be two phases for the 5G normative work consid- ering various usage scenarios, requirements, and urgent commercial demands. The first phase addresses a more urgent subset of the commercial needs, and the second phase addresses all the identified usage scenarios and requirements. At this time, it seemed widely agreed that, while the normative work can be phased to initially specify support for only a subset of the identified usages scenarios, and requirements, the design of the 2.4 3GPP Schedule and Phasing 2015 (Calendar Year) Release 13 Release 14 RAN 5G workshop Channel model for higher frequencies Scenarios and requirements Studies of NR access technologies Figure 2.2 3GPP schedule related to NR access technology studies. NR should be forward compatible, SO that it can optimally support the remaining usage scenarios and requirements that will be added in a later phase. After this workshop, in Releases 13 and 14, channel modeling for higher frequencies was studied to take care of spectrum above 6 GHz, and usage scenarios and require- ments were also studied. Technical reports on higher-frequency channel modeling, usage scenarios, and requirements were summarized in [13, 14], respectively. In Release 14, from 2016 to the beginning of 2017, studies of NR access technologies were conducted to identify and evaluate the candidate technologies, as shown in Figure 2.2. Technical reports of these studies were summarized in multiple reports such as [15, 16]. In Release 15, from the beginning of 2017 to 2019, the initial NR specification work was conducted to produce the initial 5G specifications called phase 1 as shown in Figure 2.3. The target objectives of the initial NR specification were set to specify the functionalities for eMBB and URLLC considering a more urgent subset of the commercial needs. At the same time, new specification work for LTE-Advanced was also conducted to extend functionality and improve perform