论文标题
DFT-Sprect-Spread正交时间频率空间系统，带有叠加的飞行员，用于Terahertz集成感应和通信
DFT-Spread Orthogonal Time Frequency Space System with Superimposed Pilots for Terahertz Integrated Sensing and Communication
论文作者
论文摘要
Terahertz（THZ）综合感应和通信（ISAC）是一种有前途的跨学科技术，它同时实现了每秒（TBPS）和毫米级准确的环境或人类活动感测。但是，沟通性能和感知精度都受到多普勒效应的影响，多普勒效应在THZ频段中尤为严重。此外，峰值与平均功率比（PAPR）降低了THZ功率放大器（PA）效率。在本文中，提出了带有叠加飞行员的离散傅立叶变换传播正交时间频率空间（DFT-S-OTFS）系统，以改善对多普勒效应的鲁棒性并减少THZ ISAC的PAPR。然后，开发了两相感测参数估计算法，以将传感功能整合到DFT-S-OTFS波形中。同时，提出了具有基于共轭梯度的均衡器的低复杂性迭代通道估计和数据检测方法，以恢复DFT-S-OTF的数据符号。与OTF相比，提出的DFT-S-OTFS波形可以平均提高PA效率10％。仿真结果表明，THZ DFT-S-OTFS系统的提出的两相感测估计算法能够实现毫米级范围的估计准确性和每秒级别速度估计的精度。此外，迭代方法在DFT-S-OTFS系统中叠加的飞行员的迭代方法的有效性通过模拟验证，并且多普勒效应不会降低位错误率性能。
Terahertz (THz) integrated sensing and communication (ISAC) is a promising interdisciplinary technology that realizes simultaneously transmitting Terabit-per-second (Tbps) and millimeter-level accurate environment or human activity sensing. However, both communication performance and sensing accuracy are influenced by the Doppler effects, which are especially severe in the THz band. Moreover, peak-to-average power ratio (PAPR) degrades the THz power amplifier (PA) efficiency. In this paper, a discrete Fourier transform spread orthogonal time frequency space (DFT-s-OTFS) system with superimposed pilots is proposed to improve the robustness to Doppler effects and reduce PAPR for THz ISAC. Then, a two-phase sensing parameter estimation algorithm is developed to integrate sensing functionality into the DFT-s-OTFS waveform. Meanwhile, a low-complexity iterative channel estimation and data detection method with a conjugate gradient based equalizer is proposed to recover the data symbols of DFT-s-OTFS. The proposed DFT-s-OTFS waveform can improve the PA efficiency by 10% on average compared to OTFS. Simulation results demonstrate that the proposed two-phase sensing estimation algorithm for THz DFT-s-OTFS systems is able to realize millimeter-level range estimation accuracy and decimeter-per-second-level velocity estimation accuracy. Moreover, the effectiveness of the iterative method for data detection aided by superimposed pilots in DFT-s-OTFS systems is validated by the simulations and the bit error rate performance is not degraded by the Doppler effects.
