Improved Detection in Successive Interference Cancellation NOMA OFDM Receiver

A successive interference cancellation receiver is one of the important blocks in non-orthogonal multiple access (NOMA) transmission. The quality of detection of the strongest user signals often decides about the quality of the whole system and minimizes the error propagation effect. In this paper, we propose an improved detection algorithm, which allows for using the NOMA transmission in a much smaller range of power differences between the terminals sharing common radio resources in the uplink, as compared with standard successive cancellation. The idea lies in the application of tentative decisions about weaker signals in the detection of stronger ones and then, after improved detection of stronger user signals, achieving more reliable decisions about the weaker ones. The simulation results reported in the paper confirm our idea, showing a much higher detection quality of the proposed receiver when compared with the standard solution.