In this letter, EH1/EH2-mode periodic leaky-wave antennas (LWAs) are proposed for achieving backward-to-forward scanning capability. In order to suppress the open stopband, the impedance balanced condition based on the modal distribution circuit is derived. From the equivalent effects of loading slots, the composite slot loadings under the impedance balanced condition are introduced and designed as a validation. The simulated propagation constants and the continuous scanning capability of the proposed LWAs show good suppression of the open stopband. Finally, two LWAs based on EH1-mode or EH2-mode are designed with single beam or dual beams scanning from −40° to 41°, respectively. The measured reflection coefficient and the radiation patterns are in good agreement with those obtained from the simulation.

中文翻译：

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具有后向扫描的微带线 EH1/EH2 模式漏波天线

在这封信中，提出了 EH1/EH2 模式周期性漏波天线 (LWA) 以实现后向到前向扫描能力。为了抑制开阻带，推导出基于模态分布电路的阻抗平衡条件。从加载槽的等效效应出发，引入阻抗平衡条件下的复合槽加载作为验证。所提出的 LWA 的模拟传播常数和连续扫描能力显示出对开阻带的良好抑制。最后，设计了两个基于 EH1 模式或 EH2 模式的 LWA，分别具有从 -40° 到 41° 的单光束或双光束扫描。测得的反射系数和辐射方向图与从模拟中获得的非常吻合。