This paper has proposed an end‐fire slot antenna with back‐lobe level suppression and front‐to‐back ratio (FBR) improvement. At first, the radiation characteristic of the conventional λ/4 slot antenna are meticulously investigated to initially demonstrate that its FBR can be maintained as high as about 6 dB. Then, the antenna under three different boundary conditions is deeply studied. The results reveal that the currents along the two sides of the metal ground are parallel to the slot radiator, resulting to affect the back‐lobe radiation level to a great degree. As such, a pair of rectangular slots is properly etched on the two sides of the metal ground for further reduction of back‐lobe radiation level and FBR improvement. Finally, a prototype antenna operating at 4.7 GHz is designed and fabricated. The measured results demonstrate that the back‐lobe is indeed greatly decreased as predicted and the measured FBR of the proposed slot antenna exceeds 25 dB, where an increment of about 19 dB than the conventional λ/4 slot counterpart is successfully obtained, thereby evidently exhibiting better end‐fire radiation performance.

中文翻译：

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具有低后瓣和改进的前后比的端射缝隙天线的建议和设计

本文提出了一种具有后瓣电平抑制和前后比（FBR）改进的端射缝隙天线。首先，对传统的λ/ 4缝隙天线的辐射特性进行了仔细的研究，以初步证明其FBR可以保持高达约6 dB。然后，对三种不同边界条件下的天线进行了深入研究。结果表明，沿着金属接地层两侧的电流与缝隙辐射器平行，从而在很大程度上影响了后瓣辐射水平。因此，在金属接地的两侧适当蚀刻了一对矩形槽，以进一步降低后瓣辐射水平并改善FBR。最后，设计并制造了工作在4.7 GHz的原型天线。