论文标题
RIS辅助的联合定位和与单人体MMWave接收器同步
RIS-aided Joint Localization and Synchronization with a Single-Antenna MmWave Receiver
论文作者
论文摘要
在不久的将来，使用单个安德滕纳接收器的MMWave多输入单输出（MISO）系统被认为是有前途的解决方案，然后在成熟的5G MIMO被广泛广泛。但是，除非使用双向传输，否则不能与用户本地化共同执行误差系统同步。在本文中，我们表明，由于使用可重构智能表面（RIS），仅在下行链路误差传输的情况下，可以进行联合定位和同步。得出了位置和时钟偏移的直接最大似然（ML）估计器。为了获得ML优化的良好初始化，还设计了一个脱钩，放松的位置和延迟估计器，这不需要时钟偏移的知识。结果表明，所提出的方法即使对于系统参数的中等值，也达到了Cramér-Rao的下限。
MmWave multiple-input single-output (MISO) systems using a single-antenna receiver are regarded as promising solution for the near future, before the full-fledged 5G MIMO will be widespread. However, for MISO systems synchronization cannot be performed jointly with user localization unless two-way transmissions are used. In this paper we show that thanks to the use of a reconfigurable intelligent surface (RIS), joint localization and synchronization is possible with only downlink MISO transmissions. The direct maximum likelihood (ML) estimator for the position and clock offset is derived. To obtain a good initialization for the ML optimization, a decoupled, relaxed estimator of position and delays is also devised, which does not require knowledge of the clock offset. Results show that the proposed approach attains the Cramér-Rao lower bound even for moderate values of the system parameters.
