CORDEIRO JUNIOR, J. E.; http://lattes.cnpq.br/6322746999540332; CORDEIRO JÚNIOR, Joel Eugênio.
Resumen:
In recent years, the number of users of mobile communications services has grown signif-
icantly, and there are predictions that this number will continue growing with the arrival
of the Internet of Things (IoT). In addition, new communications services are demand-
ing ever-increasing data rates. However, the increase in the number of users and the data
rate is limited by the spectrum bandwidth available for these services. In this context, the
Non Orthogonal Multiple Access (NOMA) technique presents itself as a strong candidate to
promote spectrum sharing in next generation mobile communications systems (5G). The
NOMA technique further exploits the power domain to multiplex users and increase the cell
capacity region, taking advantage of the channel gain difference among users. The NOMA
performance is conditioned by the choice of user pairs and individual transmission power
levels. This work evaluates methods of user pairing and power allocation (UPPA) in the
NOMA on downlink, seeking to increase spectral efficiency, and maintaining high fairness
levels among users. In order to investigate the proposed methods performance, a system
level simulator (SLS) is developed, which allows the evaluation of NOMA techniques in
a multiuser environment. From the analysis developed, a fairness criterion based on the
paired users SINR fraction is proposed. In compliance with this criterion, the calculation of
the fair power allocation coefficient is derived. In addition, a user pairing strategy is used
to balance the opportunities for gains among peers. The results of the simulations indicate
that the proposed method is better than Orthogonal Multiple Access and others resource al-
location methods in NOMA, in terms of efficiency and fairness. It is also shown that NOMA
can be exploited to reduce the transmission power and interference generated.
