1. Z. Wei, J. Yuan, D.W.K. Ng, E. Maged, Z. Ding, A survey of downlink non-orthogonal multiple access for 5G wireless communication networks. ZTE Commun. 14(4), 17–25 (2016)
2. L. Dai, B. Wang, Y. Yuan, S. Han, I. Chih-Lin, Z. Wang, Non-orthogonal multiple access for 5G: solutions, challenges, opportunities, and future research trends. IEEE Commun. Mag. 53(9), 74–81 (2015)
3. Z. Ding, Z. Yang, P. Fan, H.V. Poor, On the performance of non-orthogonal multiple access in 5G systems with randomly deployed users. IEEE Signal Process. Lett. 21(12), 1501–1505 (2014)
4. J. Seo, Y. Sung, Beam design and user scheduling for nonorthogonal multiple access with multiple antennas based on pareto optimality. IEEE Trans. Signal Process. 66(11), 2876–2891 (2018)
5. V.-D. Nguyen, H.D. Tuan, T.Q. Duong, H.V. Poor, O.-S. Shin, Precoder design for signal superposition in MIMO-NOMA multicell networks. IEEE J. Sel. Areas Commun. 35(12), 2681–2695 (2017)