Enhancing NOMA Performance through the Combination of Spatial Sectorization and Near-Far User Pairing

This research aims to enhance the performance of Non-Orthogonal Multiple Access (NOMA) through a combination of spatial sectorization and near-far user pairing. Spatial sectorization is used to group users based on location, followed by pairing users within each sector based on channel gain. To reduce inter-user interference, an orthogonal principle is applied by differentiating frequencies among user pairs within each sector. The Sequential Power Allocation (SePA) algorithm is implemented for optimal power allocation to support the effectiveness of Successive Interference Cancellation (SIC) at the receiver. Simulation results show that the integration of sectorization and near-far user pairing increases the sum rate to $3.78 \times 10^{12} \mathrm{bps}$ at a transmit power of ${3 0} \mathrm{dBm}$, outperforming conventional NOMA and Orthogonal Multiple Access (OMA). The Bit Error Rate (BER) analysis also shows a significant reduction in error. These findings indicate that integrating spatial sectorization and nearfar user pairing is an effective approach to improve spectral efficiency and user access fairness in NOMA networks.