This communication presents the experimental validation of independent and wide beam scanning with a dual-band transmitarray antenna (TA) in Satcom up- and down-links at Ka -band. The TA consists of two subarrays: one operates in the down-link with central frequency at 19.5 GHz, while the other one operates in the up-link centered at 29 GHz. Both subarrays share a common radiating aperture to obtain the compact configuration. The TA layout is made of 1 bit unit-cells and its design relies on the bifocal technique to extend the beam-scanning capability. The proposed bifocal prototype includes 1500 up-link unit-cells in a $30\times50$ matrix and 1581 down-link unit-cells arranged in a $31\times51$ rectangular lattice. The 1-D scanning is validated by displacing the feed horn along one direction. We show that the TA beam can be scanned in a ±40° and ±30° independently in each band while keeping a very low scan loss (<2 dB).

中文翻译：

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适用于Satcom应用的低扫描损耗双频发送阵列

该通讯介绍了Satcom上行链路和下行链路中双频带发射阵列天线（TA）进行的独立和宽波束扫描的实验验证 K a -乐队。TA由两个子阵列组成：一个子阵列在下行链路中以19.5 GHz的中心频率工作，而另一个子阵列在中心频率为29 GHz的上行链路中工作。两个子阵列共享一个公共的辐射孔径以获得紧凑的配置。TA布局由1位单位单元构成，其设计依赖于双焦点技术来扩展束扫描功能。拟议的双焦点原型包括一个1500个上行链路单位单元。 $ 30 \次50 $ 矩阵和1581个下行链路单位单元 $ 31 \次51 $ 矩形格子。一维扫描通过沿一个方向移动进纸喇叭来验证。我们表明，TA光束可以在每个频带中独立地在±40°和±30°范围内扫描，同时保持非常低的扫描损耗（<2 dB）。