标题： 正交时频空调制的低复杂度迭代Rake检测器 显示英文标题

标题： Low Complexity Iterative Rake Detector for Orthogonal Time Frequency Space Modulation

摘要： 本文提出了一种线性复杂度的迭代梳状检测器，用于最近提出的正交时频空间（OTFS）调制方案。 基本思想是使用最大比合并（MRC）、等增益合并和选择合并等线性分集合并方案，在时延-多普勒网格中提取和合并接收到的传输符号的多径分量，以提高合并信号的信噪比。 我们通过在时延-多普勒网格中放置一些零符号，将OTFS的输入输出关系重新表述为向量形式，从而利用信道矩阵的块循环特性。 利用新的输入输出关系，我们提出了一种基于MRC方案的低复杂度迭代检测器。 所提出的检测器的比特错误率（BER）性能将与最先进的信息传递检测器以及采用单tap最小均方误差（MMSE）均衡器的正交频分复用（OFDM）方案进行比较。 我们还表明，通过采用以涡轮判决反馈均衡器（DFE）形式工作的纠错编码，可以提高MRC检测器的帧错误率（FER）性能。 显示英文摘要

摘要： This paper presents a linear complexity iterative rake detector for the recently proposed orthogonal time frequency space (OTFS) modulation scheme. The basic idea is to extract and combine the received multipath components of the transmitted symbols in the delay-Doppler grid using linear diversity combining schemes like maximal ratio combining (MRC), equal gain combining and selection combining to improve the SNR of the combined signal. We reformulate the OTFS input-output relation in the vector form by placing some null symbols in the delay-Doppler grid thereby exploiting the block circulant property of the channel matrix. Using the new input-output relation we propose a low complexity iterative detector based on the MRC scheme. The bit error rate (BER) performance of the proposed detector will be compared with the state of the art message passing detector and orthogonal frequency division multiplexing (OFDM) scheme employing a single tap minimum mean square error (MMSE) equalizer. We also show that the frame error rate (FER) performance of the MRC detector can be improved by employing error correcting codes operating in the form of a turbo decision feedback equalizer (DFE).