This letter proposes a 400-GHz leaky-wave antenna with low sidelobe level (SLL) and low cross-polarization level (CPL). Tapered radiation slots are designed for achieving a low SLL, virtual electrical walls are deployed to remove the loss from metal sidewalls by using a high-order mode feeding network, and a symmetrical layout with alternative-phase excitations is adopted for the array to suppress the CPL. The conventional computer numerical controlled metal-milling and printed-circuit-board processes are used to fabricate the designed prototype. Experiments are carried out to verify the design. The measured peak gain and radiation efficiency of the fabricated prototype are 21.32 dBi and 34.65% at 395 GHz, respectively. In addition, its measured SLL and CPL are about −25 and −30 dB, respectively. The proposed antenna shows merits of the low cost, low SLL and CPL performance for potential terahertz applications.

中文翻译：

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具有低旁瓣电平和低交叉极化电平的 400GHz 低成本平面漏波天线

这封信提出了一种具有低旁瓣电平 (SLL) 和低交叉极化电平 (CPL) 的 400 GHz 漏波天线。锥形辐射槽旨在实现低 SLL，部署虚拟电墙，通过使用高阶模式馈电网络消除金属侧壁的损耗，阵列采用交替相位激励的对称布局，以抑制CPL。传统的计算机数控金属铣削和印刷电路板工艺用于制造设计的原型。进行实验以验证设计。所制造原型的测量峰值增益和辐射效率在 395 GHz 下分别为 21.32 dBi 和 34.65%。此外，其测得的 SLL 和 CPL 分别约为 -25 和 -30 dB。建议的天线显示出低成本的优点，