Multiuser detection for uplink non‐orthogonal multiple access system

Non‐orthogonal multiple access (NOMA) makes multiple users to overload the same wireless resources by utilising the superposition coding principle, so that NOMA can improve the system capacity and spectral efficiency. Therefore, NOMA has recently received considerable attention as a promising candidate to address some of the challenges for 5G. Various NOMA schemes including the power‐domain NOMA (PD‐NOMA) are proposed, and successive interference cancellation (SIC) is applied for detection, which limits the promised performance gain brought by NOMA due to the error propagation. In this study, the authors introduce an iterative interference cancellation (IIC) detection scheme for uplink PD‐NOMA system by using parallel interference cancellation (PIC) scheme. The interleave division multiple access is also employed for improving system performance. A new detection scheme based on IIC is proposed, which is called advanced IIC (AIIC). The simulation results show that the bit error rate performance of AIIC is much better than that of SIC, and is close to that of maximum a posteriori. The AIIC can obtain the promised performance gain brought by NOMA.