OFDM-IM NOMA is a newly created flexible scheme for future generation communication systems. For the downlink OFDM-IM NOMA system, a low-complexity "rotated constellation based log likelihood ratio (LLR) detector" has been proposed in this work. This detector is able to significantly reduce the complexity by employing the rotating constellation-based concept and the log-likelihood ratio-based algorithm together. Complexity analysis and simulation results show that the proposed detector achieves significantly lower computational complexity and much better error performance than the earlier introduced detectors under different scenarios for the OFDM-IM NOMA scheme.

翻译：OFDM-IM NOMA是为未来通信系统新近提出的一种灵活方案。针对下行链路OFDM-IM NOMA系统，本文提出了一种低复杂度的"基于旋转星座的对数似然比(LLR)检测器"。该检测器通过联合运用旋转星座概念与对数似然比算法，能够显著降低复杂度。复杂度分析与仿真结果表明，在OFDM-IM NOMA方案的不同场景下，所提检测器相比先前提出的检测器，不仅计算复杂度大幅降低，而且误码性能显著提升。