The designing of efficient signal detectors is important and yet challenge for orthogonal time frequency space (OTFS) systems in high-mobility scenarios. In this letter, we develop an efficient message feedback interference cancellation aided unitary approximate message passing (denoted as UAMPMFIC) iterative detector, where the latest feedback messages from variable nodes are utilized for more reliable interference cancellation and performance improvement. A fast recursive scheme is leveraged in the proposed UAMP-MFIC detector to prevent complexity increasing. To further alleviate the error-propagation and improve the receiver performance, we also develop the bidirectional symbol detection structures, where Turbo UAMP-MFIC detector and iterative weight UAMP-MFIC detector are proposed to efficiently fuse the estimation results of forward and backward UAMP-MFIC detectors. The simulation results are finally provided to demonstrate performance improvement of our proposed detectors over existing detectors.

翻译：针对高移动性场景下的正交时频空（OTFS）系统，高效信号检测器的设计至关重要且充满挑战。本文提出一种消息反馈干扰消除辅助的酉近似消息传递（UAMPMFIC）迭代检测器，该检测器利用变量节点最新的反馈消息实现更可靠的干扰消除与性能提升。所提UAMP-MFIC检测器采用快速递归方案以避免复杂度增加。为进一步减轻误差传播并提升接收机性能，本文还开发了双向符号检测结构，分别提出Turbo UAMP-MFIC检测器和迭代加权UAMP-MFIC检测器，以有效融合前向与后向UAMP-MFIC检测器的估计结果。最后通过仿真结果验证了所提检测器相较于现有检测器的性能提升。