tes more power to the User 2. This is because User 2 is far away from the BS and hence would require more power as compared to User 1 which is closer to the BS. When User 1 receives the superimposed signal from the BS, it first carries out SIC to detect and remove message of User 2 and then detects its own message. On the other hand, User 2 detects its own message from the superimposed signal by considering the message User 1 User 1 User 2 (Performs SIC) SIC performed Time/Frequency User-1 decodes on message of User-2 its message User-2 decodes its message treating User 1's message User-2 as Interference (no SIC performed) Base Station Fig. 5.1 Basic concept of NOMA [21] P. Swami and V. Bhatia of User 1 as interference as described in Fig. 5.1. Therefore, it can be seen that the method of detection of self message differs from User 1 and User 2 after receiving of the same superimposed signal. This difference arises because of the difference in channel gain condition of both the users. Following this way, NOMA achieves massive connectivity and efficient utiliza- tion of spectrum. As per the theoretical research on comparison of NOMA with orthogonal multiple access, it is observed that NOMA achieves higher system throughput [22]. The reason is that although splitting of power takes place in NOMA, however, benefit of larger bandwidth is also present in NOMA. This increases the overall system performance. Furthermore, as the difference in channel gain between the users increases, the system throughput also increases. 5.2.1 Various Applications of NOMA NOMA provides massive connectivity to support various applications, e.g., for the integrated system such as vehicle-to-everything (V2X) which has been proposed such that vehicles are able to communicate by themselves. For the application of V2X, NOMA has been considered as a key technology to support various simultaneous applications [23]. Furthermore, NOMA with cooperative relaying is a natural extension since the message of far user is also sent to the near user and t