A2: Metrology of Multi-Dimensional Channel Sounding

项目A2第一阶段的主要目标是“研究和比较实时宽带探测器结构，并制定校准程序，以便在所用测量装置尽可能减少失真的情况下估计多路径传播的几何模型”。在所取得成果的基础上，我们将在第二阶段致力于增强的探测器架构，该架构克服了我们以前设置的局限性，并实现了雄心勃勃的计量级THz无线电系统评估。首先，我们将受益于任意波形处理的灵活性。多载波信号设计和预失真方案将导致增强的探测器校准程序和增加的Tx功率效率。另一优点来自多载波激励信号再现典型OFDM和SC-FDMA通信波形的预定义包络统计的能力。这用于估计在某些应用情况下RF子系统的非线性感应失真行为。其次，预期的相干多通道RF架构为THz探测器应用提供了前所未有的功能。在第一阶段结束时，我们将有一个300 GHz的2x2四极化收发器无线电接口可用。这将进一步用于证明项目A1中正则参考伪影的偏振特征的识别。这将为THz通信的集成通信和传感应用铺平道路，例如基于雷达的SLAM导航（SLAM：同时定位和映射）。另一个重要的步骤是使用4单元接收阵列，该接收阵列可与四个相干下变频器一起使用。因此，与任意波形无线电接口的实时能力，我们将证明真正的联合延迟/多普勒/DoA分辨率（DoA：到达方向）在动态场景。这开辟了新的视角，引入多维时变，定向无线电系统的系统计量。此外，我们将多维方法扩展到DoD估计（DoD：偏离方向）。我们将证明，联合DoA/DoD分辨率是必要的波传播的正确的双向表征和全面的系统级评估太赫兹收发器，使用定向天线，最显着的阵列，在链路的两侧。最后，计划的设置将允许模拟分布式多链路和多跳网络结构。这为这些先进的太赫兹无线电系统的计量级评估提供了新的视角。第三，我们将进一步开发我们的基于模型的估计过程，以处理丢失的载波和稀疏载波分配，并处理扩展对象显示分散的响应和特征极化签名。

The major objective in the first phase of the project A2 was “the study and comparison of real-time broadband sounder architectures and the development of calibration procedures that allow the estimation of the geometric model of multipath propagation with the least possible distortion by the measurement device used”. On the basis of the results achieved, we will be working in the second phase on an enhanced sounder architecture that overcomes the limitations of our former setup and enables ambitious metrology-grade THz radio system evaluations. Firstly, we will profit from the flexibility of arbitrary waveform processing. Multicarrier signal design and predistortion schemes will lead to enhanced sounder calibration procedures and increased Tx power efficiency. Another advantage comes from the capability of multicarrier excitation signals to reproduce predefined envelope statistics of typical OFDM and SC-FDMA communication waveforms. This is used to estimate the nonlinear induced distortion behavior of RF subsystems in certain application situations. Secondly, the intended coherent multichannel RF-architecture offers unprecedented features for THz sounder application. Already at the end of the first phase, we will have a 2x2 quad-polarimetric transceiver radio interface at 300 GHz available. This will be further used to demonstrate the identification of polarimetric signatures of canonic reference artifacts from project A1. This shall pave the way for integrated communication and sensing applications of THz communications, e.g. radar based SLAM navigation (SLAM: Simultaneous Localization and Mapping). Another important step is the use of a 4-element receive array which becomes available with four coherent down converters. Thereby and with the real-time capability of the arbitrary waveform radio interface, we will demonstrate true joint delay/Doppler/DoA resolution (DoA: direction of arrival) in dynamic scenarios. This opens new perspectives to introduce multidimensionality to system metrology of time-variant, directive radio systems. Moreover, we will extend the multidimensionality approach to DoD estimation (DoD: direction of departure). We will demonstrate that joint DoA/DoD resolution is necessary for a correct bidirectional characterization of wave propagation and a comprehensive system level evaluation of THz transceivers that use directive antennas, most notably arrays, at both sides of the link. Finally, the planned setup will allow emulating distributed multilink and multi-hop network structures. This offers new perspectives for metrology-grade evaluation of these advanced THz radio systems. Thirdly, we will further developed our model-based estimation procedure to deal with missing carriers and sparse carrier allocation and to handle extended objects showing a dispersive response and a characteristic polarimetric signature.