论文标题
最佳的双向TOA本地化和使用时钟漂移的移动用户设备的同步
Optimal Two-way TOA Localization and Synchronization for Moving User Devices with Clock Drift
论文作者
论文摘要
在双向到达的时间（TOA）系统中，用户设备（UD）通过往返通信与已知位置的许多锚节点（ANS）获取其位置和计时信息。与单向TOA技术相比，双向TOA方案易于实现，并且具有更高的定位和同步精度。现有的双向TOA方法假设固定UD。这将导致无偿的位置和定时错误。在本文中，我们提出了基于最佳的最大可能性（ML）的双向TOA定位和同步方法，即TWLA。与现有方法不同，它将UD移动性考虑在内，以补偿由UD运动引起的错误。我们分析其估计误差并得出CRAMER-RAO下限（CRLB）。我们表明，当UD固定时，常规的双向TOA方法是TWLA的特殊情况，并且TWLA具有高估计精度，而不是常规的单向TOA方法。在偏差的UD速度信息的情况下，我们还会得出估计误差。数值结果表明，新的TWLA对于移动UD的估计精度达到CRLB，比常规的单向TOA方法的估计精度更好，并且由偏差的UD速度信息引起的估计误差与理论分析一致。
In two-way time-of-arrival (TOA) systems, a user device (UD) obtains its position and timing information by round-trip communications to a number of anchor nodes (ANs) at known locations. Compared with the one-way TOA technique, the two-way TOA scheme is easy to implement and has higher localization and synchronization accuracy. Existing two-way TOA methods assume a stationary UD. This will cause uncompensated position and timing errors. In this article, we propose an optimal maximum likelihood (ML) based two-way TOA localization and synchronization method, namely TWLAS. Different from the existing methods, it takes the UD mobility into account to compensate the error caused by the UD motion. We analyze its estimation error and derive the Cramer-Rao lower bound (CRLB). We show that the conventional two-way TOA method is a special case of the TWLAS when the UD is stationary, and the TWLAS has high estimation accuracy than the conventional one-way TOA method. We also derive the estimation error in the case of deviated UD velocity information. Numerical result demonstrates that the estimation accuracy of the new TWLAS for a moving UD reaches CRLB, better than that of the conventional one-way TOA method, and the estimation error caused by the deviated UD velocity information is consistent with the theoretical analysis.
