We present a metasurface-enabled cavity antenna that achieves full beam steering but features a significantly reduced number of fed elements. To create this antenna, we first excite a traveling wave in a cavity enclosed by an active metasurface, then form the desired radiation by leaking the cavity wave through a perforated top plate. We hence achieve a steerable antenna for which the number of fed elements scales with the perimeter and not the area of the radiation aperture. In this letter, we report two models of this cavity antenna whose beamwidths and sidelobe levels closely resemble a traditional microstrip patch array of the same aperture size. Hence, dramatic savings in feed cost and complexity are achieved without compromising the antenna gain, the beam shape, or steerability. The proposed antennas shall attract strong interest in highly directive millimeter-wave beamforming applications.

中文翻译：

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支持超表面的空腔天线：波束控制，馈电元件显着减少

我们提出了一种支持超表面的腔天线，它实现了全波束控制，但馈电元件的数量显着减少。为了创建这个天线，我们首先在一个由有源超表面包围的腔中激发行波，然后通过将腔波通过穿孔顶板泄漏来形成所需的辐射。因此，我们实现了一种可操纵的天线，其馈电元件的数量与周长而不是辐射孔径的面积成比例。在这封信中，我们报告了这种腔体天线的两种模型，其波束宽度和旁瓣电平非常类似于具有相同孔径尺寸的传统微带贴片阵列。因此，在不影响天线增益、波束形状或可操纵性的情况下，可以显着节省馈电成本和复杂性。