Reflectarrays and tunable surfaces receive increasing attention for wavefront engineering in the upper millimeter-wave range. As chip-based phase shifters can now be integrated with antenna elements, the performance verification at unit cell (UC) level is of great interest for a cost-efficient investigation of large-scale arrays. In this article, two UC designs with integrated phase shifter and on-chip antenna are evaluated experimentally at 240 GHz. For the first time, a single element is characterized above 100 GHz by applying the classic waveguide simulator technique. Since this method is mechanically problematic at high frequencies due to small dimensions and mechanical tolerances, an alternative approach involving a near-field probe is presented and investigated. The results for both measurement methods are compared and interpreted, assisted by full-wave simulations.

中文翻译：

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240 GHz 可重构反射阵列单元的表征技术


反射阵列和可调表面在上毫米波范围内的波前工程中受到越来越多的关注。由于基于芯片的移相器现在可以与天线元件集成，因此单位单元（UC）级别的性能验证对于大规模阵列的成本效益研究非常重要。在本文中，两种具有集成移相器和片上天线的 UC 设计在 240 GHz 下进行了实验评估。通过应用经典的波导模拟器技术，首次在 100 GHz 以上对单个元件进行了表征。由于尺寸小和机械公差，这种方法在高频下存在机械问题，因此提出并研究了一种涉及近场探头的替代方法。在全波模拟的帮助下，对两种测量方法的结果进行了比较和解释。