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Non-orthogonal Multiple Access (NOMA) is proposed as a new multiple access for 5G communication. However, one of the crucial constraints is near-far effect that occurs to the NOMA downlink and serial interference cancellation (SIC). To avoid near-far effect, we propose 3D beam forming application based on antenna polarization in M-MIMO systems to re-group users. The proposed scheme effectively reduces the number of users within the beam coverage. On the other hand, we propose a method that adaptively selects channel estimation method according to the power of the user in SIC process to eliminate the effect.