The impact of user mobility into non-orthogonal multiple access (NOMA) transmission systems

Non-orthogonal multiple access techniques (NOMA) have been recognized as a paradigm shift for the design of multiple access techniques for the next generation of wireless networks. Many existing works on NOMA have focused on scenarios with low-mobility users (static), where users with different channel conditions or quality of service (QoS) requirements are grouped together for the implementation of NOMA. However, when increased, user mobility can strongly impacts on the performance of a NOMA systems, especially in the context of downlink perceived throughput, networ fairness and QoS fuilfilment of each users. This paper presents some of the main drawback which can be obtained if the user mobility is not taken into account in the design of NOMA communication systems. Future direction and challenges to address these issues are also discussed. Received on 02 October 2020; accepted on 16 October 2020; published on 21 October 2020