4-port vector network analyzer

在技术进步方面，可以实现在小型化设置中具有多个发送和接收通道的以不断增加的频率操作的紧凑型多端口系统。频率约为100 GHz的一些突出例子是自动驾驶或工业流程工业中的测量系统所需的基于雷达的传感器系统。高频高精度测量技术是高频系统座椅的主要研究课题之一。实际的研究项目涉及多端口网络分析仪的校准，重点是研究自校准方法、替代误差模型和用于校准的网络的有效选择。此外，还研究了基于MIMO系统(多输入多输出)和雷达传感器的材料表征和成像方法。对于多端口矢量网络分析仪校准领域的研究，该测量系统的应用具有重要意义。在某种程度上，分析器本身及其内部架构甚至成为调查对象。实际上，只有通过高达40 GHz的多端口网络分析仪的测量才能验证理论研究结果。该测量系统是一个原型系统，在一年的时间内提供给研究人员使用。该系统现在不再可用。为了能够继续这一领域的研究工作，并针对将频率范围提高到110 GHz的实际国际研究课题，迫切需要所应用的四端口矢量网络分析仪。对于电磁材料表征领域的研究来说，材料性质的测量是必不可少的，因为材料的相对介电常数以及损耗通常与频率有关。为此，由所申请的测量系统支持的大频率带宽是非常有意义的，因为这使得研究用于材料表征的信号分析的创新方法成为可能。通过这种方式，可以研究光谱分析，这意味着使用材料的特征频率行为进行唯一识别的方法。此外，由于高带宽可以实现测量的高时间分辨率，因此可以有利地检查时间域中的方法。此外，对于基于聚焦天线、反射镜或可应用的后处理算法的成像方法的研究，该装置非常有吸引力。因此，用空间分辨率表示材料特征以识别不均质性、包裹体或热蚀变成为可能。此外，基于不同偏振的透射量测和反射量测的椭圆偏振测量方法可以并行研究。

With respect to technological progress, compact multi-port systems operating at increasing frequencies with multiple transmit and receive channels in a miniaturized setup can be realized. Some prominent examples for frequencies at about 100 GHz are radar based sensor systems as needed for autonomous driving or for measurement systems in industrial process industry. High frequency high precision measurement techniques are one of the main research topics of the chair for high frequency systems. Actual research projects are concerned with the calibration of multiport network analyzers with a focus on the investigation of self-calibration methods, alternative error models and an efficient choice of networks for calibration. In addition, methods for material characterisation and for imaging purposes based on MIMO-systems (multiple input multiple output) as well as radar sensors are investigated.For research in the field of multiport vector network analyzer calibration, the measurement system as applied for, is of significant importance. Partially, the analyzer on its own with its internal architecture even becomes an object of investigation. Actually, it was only possible to verify the theoretical research results by measurements with a multiport network analyzer up to 40 GHz. This measurement system was a prototype setup, which was made available for the researcher restricted in time for one year. The system is no longer available now. In order to be able to continue research work in this field and with respect to actual international research topics to increase the frequency range up to 110 GHz, the 4-port vector network analyzer as applied for is strongly needed. For research in the field of electromagnetic material characterization the measurement of the material properties is essentiell, because the relative permittivity as well as the loss of the material are generally frequency dependent. For this purpose, a large frequency bandwidth as being supported by the measurement system applied for, is of high interest, because this enables the investigation of innovative methods for signal analysis for material characterization. In this way spectroscopic analysis can be studied, this means methods that use the characteristic frequency behaviour of the material for unique identification. Furthermore, methods in time domain can be examined advantageously, because due to the high bandwidth a high resolution in time can be achieved for the measurements. In addition, the setup is very attractive for the investigation of imaging methods based on focussing antennas, mirrors or post-processing algorithms which can be applied. Thus, the representation of the material characteristics with a spatial resolution for the identification of inhomogenities, inclusions or thermal alteration becomes possible. Further on, ellipsometric methods, based on transmission and reflection measurements with different polarisations can be investigated in parallel.