Investigating new approaches for narrowband but nevertheless high-precision wireless locating in multipath environments by means of iterative recursive non-linear state estimation techniques based on aperture synthesis and phase difference analysis in ant

该项目的目的是研究一种新颖，低成本但高度精确的无线局部定位概念及其基本理论原理，并通过系统理论和实验验证系统性能。该计划的显著特点是，即使在窄带信号下，也能在恶劣的多径环境下提供高精度的3D定位结果。对于以前的无线电定位技术，如UWB无线电定位系统，可实现的定位精度通常直接依赖于所使用的信号带宽，由于具有挑战性的带宽要求和通常不利的几何精度稀释（GDOP），精确的3D定位很少得到实验证明。这种开拓性解决方案的预期性能，将代表对当前技术状态的巨大改进，是通过迭代递归非线性状态估计技术实现的。为此目的，在混合相干/非相干天线阵列星座中接收的无线电信号的相位差将以一种与干涉孔径合成算法相当的方式进行评估。而不是使用傅里叶或其他频谱估计技术，相位值直接由迭代扩展卡尔曼滤波器（EKF）处理。在研究了本项目提出的系统并实现了必要的算法之后，系统将在模拟环境中进行系统研究，然后在实验装置中进行实际测试。在项目期间实施的24 GHz实验系统包括四个分布式紧凑接收器阵列，每个阵列有16个天线。该项目的目的是首次展示在密集多径环境中带宽小于10mhz的信号在毫米范围内的3D定位精度。开发一种新的通用方法来验证定位系统是研究工作的另一个关键方面。这是必要的，因为通常使用的基于gdp的方法来预测/估计作为系统参数函数的位置不确定性，不适用于本项目中采用的方法，在该项目中，测量的获取和融合是集成的。目的是建立一个基于新的理论模型的平台。该平台将允许首次系统客观地比较经典定位原理和新解决方案的性能作为系统参数的函数，以及考虑传输信道和多径传播的参数。

The aim of the project is to investigate a novel, low-cost but nevertheless highly accurate concept for wireless local positioning and the underlying theoretical principles, and to verify system performance both through the lens of systems theory and experimentally. The salient feature of the initiative is its potential to deliver highly accurate 3D locating results in severe multipath environments, even with narrowband signals. With previous radiolocation techniques, such as UWB radiolocation systems, the achievable positioning accuracy is typically directly dependent on the signal bandwidth used, and precise 3D positioning has rarely been demonstrated experimentally due to the challenging bandwidth requirements and the usually unfavorable geometric dilution of precision (GDOP). The expected performance of this pioneering solution, which would represent an enormous improvement over the state of the art, is to be achieved by iterative recursive nonlinear state estimation techniques. For this purpose the phase differences of the radio signals received in mixed coherent/incoherent antenna arrays constellations will be evaluated in a way comparable to an interferometric aperture synthesis algorithm. However, instead of using of Fourier or other spectral estimation techniques the phase values are directly processed by an iterative Extended Kalman Filter (EKF). Having studied the system proposed in this project and implemented the necessary algorithms, the system will be systematically investigated in a simulation environment and then tested in practice in an experimental setup. The 24 GHz experimental system to be implemented during the project comprises four distributed compact receiver arrays with 16 antennas each. The aim of the project is to demonstrate for the first time 3D positioning accuracy in the millimeter range for signals with a bandwidth of less than 10 MHz in a dense multipath environment. The development of a new general-purpose methodology for validating positioning systems is another key aspect of the research work. This is necessary because commonly used GDOP-based methodologies for predicting/estimating positional uncertainties as a function of system parameters are unsuitable for the methodology adopted in this project, where the acquisition and fusion of the measurements are integrated. The aim is to create a platform based on the new theoretical model. This platform will allow classical localization principles and this new solution to be compared systematically and objectively for the first time with respect to performance as a function of the system parameters and also with respect to the parameters that take into account the transmission channel and multipath propagation.