Measurement concepts for new, highly integrated antennas

该提案是DFG项目的后续应用，主题为高度集成天线的测量技术概念。该项目的主要重点是深入分析从100 GHz到300 GHz的集成天线的测量概念和可实现的测量精度。最小的传感器尺寸和大的可用绝对带宽导致对毫米波范围内的集成传感器的高度研究兴趣。然而，所需的集成天线的特性是具有挑战性的，因为小的结构尺寸和短的波长需要复杂的测量设置。由于芯片尺寸很小，用于馈电天线的接触夹具位于AUT的直接周围，通常比被测设备本身大得多。这导致了较大的系统测量误差。在通过对设置进行彻底的误差分析来显著提高测量精度之后，现在将详细分析剩余的误差机制，如晶片探头反射或与焊线和封装的相互作用。首先，将来自天线的期望的直接辐射与不需要的反射分离，以获得隔离天线的辐射场。通过将由此过滤的场与原始测量值进行比较，可以更好地理解发生误差的机制和相互作用。为此，采用了两种算法，即MARS算法和源重建算法。然而，由于晶片探头的强烈反射，识别键合导线和封装的影响可能会很困难。因此，实现了一种新的测量方法，允许通过芯片上直接产生的信号来馈电AUT的相位测量，而不是通过来自外部源的晶片探头提供的信号。测量数据的后处理也可以用较低价格的标准探头来表征集成天线。到目前为止，集成天线的准确测量只有在使用针对天线测量进行优化的晶片探头时才可能实现。标准探头后面的信号的反射和阴影会导致很大的测量误差，从而阻碍有意义的测量。因此，使用后处理算法来重建实际的辐射方向图，并定位探头的反射中心，根据天线的增益和方向性来计算天线的精度。到目前为止，测量效率的准确性受到集成天线增益测量误差的限制。为了改进效率测量，对增益比较测量中出现的误差进行了详细的分析。

This proposal is a subsequent application to the DFG project with the topic Measurement Technique Concepts for Highly Integrated Antennas. The main focus of the project were in-depth analyses of measurement concepts and of the achievable measurement accuracy for the characterization of integrated antennas from 100 GHz to 300 GHz.Minimal sensor sizes and large available absolute bandwidths lead to a high research interest towards integrated sensors in the millimeter wave range. However, the characterization of the required integrated antennas is challenging, as the small structure sizes and the short wavelengths require elaborate measurement setups. Due to the small chip dimensions the contacting fixtures, which are used to feed the antenna, are in the immediate surrounding of the AUT and are usually much bigger than the device under test itself. This leads to large systematic measurement errors. After the measurement accuracy has been improved considerably through a thorough error analysis of the setup, the remaining error mechanisms, like wafer probe reflections or interaction with bond wires and the packages, are now to be analyzed in detail. First, the desired direct radiation from the antenna is separated from the unwanted reflections to obtain the radiated field of the isolated antenna. By comparing the thereby filtered fields to the original measurements, a better understanding of the occurring error mechanisms and interactions can then be obtained. Two algorithms are employed for this, namely MARS and source reconstruction.Identifying the influence of bond wires and package can, however, be difficult due to the strong reflections from the wafer probe. Therefore, a new measurement method is realized to allow phase measurements of an AUT that is fed by a signal generated directly on the chip, instead of a signal supplied through a wafer probe from an external source.Post processing of the measurement data can also allow the characterization of integrated antennas with lower-priced standard probes. Until now accurate measurements of integrated antennas are only possible when wafer probes are used that are optimized for antenna measurements. Reflections and shadowing of the signal behind standard probes cause large measurement errors that inhibit meaningful measurements. Therefore, the post processing algorithms are used to reconstruct the actual radiation pattern and to locate the reflection centers of the probe.The accuracy of antennas can be calculated with gain and directivity of an antenna. So far the accuracy of the determined efficiency is limited by errors in the integrated antenna gain measurement. In order to improve efficiency measurements, a detailed analysis of errors, which occur in gain comparison measurements, is conducted.