A dual-band beam-scanning antenna by rotation of two transmintarrays (TAs) operating at 20 and 30 GHz has been presented in this letter. TA's unit cell has three metal layers and demonstrates almost completely independent performance at two frequency bands. Two designed TAs have unit cells of different sizes to achieve dual-band with different linear phases. By rotating the two TAs synchronously around the axis orthogonal to the planes of the TAs, it enables two-dimensional (2-D) beam scanning with maximum scanning angles of ±40°. The achieved simulated peak gains are 19.9 dBi, 20.5 dBi and 22.5 dBi, 23.2 dBi at phi = 0°, phi = 90° at 20 and 30 GHz, respectively. The maximum beam scanning losses are 1.7 dB, 2.6 dB and 1.5 dB, 2.7 dB. Moreover, the two beams at the two frequencies can basically point to the same direction at the same time. To validate the design, a prototype is fabricated and tested. The measured results are in good agreement with the simulated results.

中文翻译：

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通过旋转两个发射阵列实现 Ka 波段双频波束扫描天线


这封信中介绍了一种通过旋转两个工作在 20 和 30 GHz 的传输阵列 (TA) 实现的双频段波束扫描天线。 TA 的单元具有三个金属层，在两个频段上表现出几乎完全独立的性能。两种设计的 TA 具有不同尺寸的单元，以实现具有不同线性相位的双频段。通过围绕与 TA 平面正交的轴同步旋转两个 TA，可以实现最大扫描角度为 ±40° 的二维 (2-D) 光束扫描。在 phi = 0°、phi = 90°（20 和 30 GHz 时）实现的模拟峰值增益分别为 19.9 dBi、20.5 dBi 和 22.5 dBi、23.2 dBi。最大波束扫描损耗为1.7 dB、2.6 dB和1.5 dB、2.7 dB。而且，两个频率的两个波束基本上可以同时指向同一个方向。为了验证设计，制造并测试了原型。测量结果与模拟结果非常吻合。