Tianyi Zeng Yongyu Chang Qi Zhang 0021 Mengshi Hu Junyao Li CNN-Based LOS/NLOS Identification in 3-D Massive MIMO Systems. 2491-2494 2018 22 IEEE Commun. Lett. 12 https://doi.org/10.1109/LCOMM.2018.2872522 db/journals/icl/icl22.html#ZengCZHL18