NOMA based Walsh Hadamard Transform and User Pairing Strategy

Non-Orthogonal Multiple Access (NOMA) is a promising multiple access technique for the 5G system, which is based on superposition coding (SC) at the transmitter and successive interference cancellations (SIC) at the receiver. The NOMA technique offers several benefits, such as high spectral efficiency, widespread connectivity, and high data rates. However, the result of resource allocation and interference cancellation is crucial to increase system throughput and enhance bit-error-rate (BER) performance. Thus, this study proposes a hybrid method based on the Walsh-Hadamard Transform (WHT) matrix and user pairing strategy. Simulation results confirm that the proposed method not only improve the BER and sum rate performance compared to the conventional NOMA, but also provied a high user fairness, enabling it to meet 5G requirements