The recently proposed orthogonal time frequency space (OTFS) modulates the data in the delay-Doppler domain, thereby the 2-D diversity gain can be obtained to improve the communication performance over time-varying channels. However, the matrix-inversion based detectors have pretty high complexity in OTFS systems due to the large size of channel matrix. This letter proposes a low complexity matched filtering based message passing detector (MF-MPD), combined with a novel probability clipping (PC) solution. Benefit from matched filtering processing, the complexity and storage requirement of this solution can be reduced, and better BER performance in low SNR regimes can be achieved. Furthermore, the BER floor at high SNRs can be obviously improved via PC over time-varying channels according to the numerical results.

中文翻译：

---

用于具有概率限幅的 OTFS 调制的低复杂度消息传递检测器

最近提出的正交时频空间 (OTFS) 在延迟多普勒域中调制数据，从而可以获得二维分集增益，以提高时变信道上的通信性能。然而，由于通道矩阵的大尺寸，基于矩阵求逆的检测器在 OTFS 系统中具有相当高的复杂性。这封信提出了一种基于低复杂度匹配过滤的消息传递检测器 (MF-MPD)，并结合了一种新颖的概率裁剪 (PC) 解决方案。受益于匹配滤波处理，该解决方案的复杂性和存储要求可以降低，并且可以在低 SNR 状态下实现更好的 BER 性能。此外，根据数值结果，可以通过 PC 在时变信道上明显改善高 SNR 下的 BER 底限。