PASS‐NOMA: Waveguide Channel‐Aware User Pairing With Adaptive SIC

This paper proposes a new framework called pinching antenna systems–nonorthogonal multiple access (PASS–NOMA), which combines the inherent physical properties of waveguide channels with the NOMA technology. The proposed system employs an adaptive pairing strategy with successive interference cancellation to increase the system’s spectral efficiency. The author has utilized the frequency‐selective properties of waveguide channels, including waveguide dispersion, coupling, and propagation of millimeter waves at 30.5 GHz, to increase the efficiency of the proposed system. The simulation results, which use 8 users and 64 subcarriers with a 2.0 GHz bandwidth, have shown that the adaptive PASS–NOMA system achieves 190.6% more throughput compared with traditional OMA schemes with an SNR of 20 dB. It is also shown that the proposed system achieves an average increase of 120.3% across SNR 5–30 dB. The SIC success rates have been found to be 99.8% for an SNR of 30 dB. The fairness index of the proposed system has been found to vary between 0.617 and 0.848, depending on the adaptive pairing strategy. The adaptive system offers a reasonable trade‐off between throughput and fairness. The proposed system achieves near‐perfect fairness of 0.848 with the random pairing strategy, and the overall system performance is robust. The simulation results have confirmed the potential of waveguide‐aware NOMA architectures for 6G indoor networks, which require high spectral efficiency and reliable multiuser connectivity.