In this article, a simple coaxial‐feed filtering patch antenna based on stub‐loaded resonator is investigated and analyzed. Owning to the addition of a pair of parasitic stubs, the original rectangular patch antenna acquires a new resonance point and an out‐side radiation null beyond the upper band edge. Then, by establishing a transverse path (introducing connected stubs), the radiating and filtering responses at lower band have been enhanced accordingly. In short, it operates like a three‐order filter with two‐constrained radiation nulls along the passband outside. The novel design has been verified by machining and testing, which meets the expected lately. A fractional bandwidth of 28% and a stable realized gain of 5.8 dBi in‐band are finally measured, and more it also reaches a higher radiation efficiency of 83%. Besides, it exhibits a unidirectional radiation pattern with a low‐cross polarization less than −20 dB in the boresight direction.

中文翻译：

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基于短管谐振器的简单滤波贴片天线

在本文中，研究并分析了一种基于短负载谐振器的简单同轴馈电滤波贴片天线。由于增加了一对寄生短截线，原始的矩形贴片天线获得了一个新的谐振点，并且超出了上频带边缘的外部辐射为零。然后，通过建立横向路径（引入连接的短截线），相应地增强了较低频带的辐射和滤波响应。简而言之，它就像一个三阶滤波器，沿外部通带具有两个约束辐射零点。新颖的设计已通过机加工和测试验证，符合最近的预期。最终测得的分数带宽为28％，带内稳定实现的增益为5.8 dBi，而且还可以达到83％的更高辐射效率。除了，