A very compact ultra‐wideband (UWB) slot antenna with three L‐shaped slots for notched‐band characteristics is presented in this article. The antenna is designed and fabricated using a new stepped slot with different size, integrated in the ground plane, and excited by a 50 Ω microstrip transmission line. The stepped slot is used to minimize the dimensions of the antenna and to achieve an impedance bandwidth between 2.65 and 11.05 GHz with voltage standing wave ratio (VSWR) less than 2. The length of the stepped slot is equal to a quarter wavelength to create a resonance in the desired frequency. Three L‐shaped slots with various sizes are etched in the ground plane to reject three frequency bands in C‐band (3.7‐4.2 GHz), WLAN (5.15‐5.825 GHz), and X‐band (7.25‐7.75 GHz), respectively. The notched‐band frequency can be controlled by changing the length of the L‐shaped slot. The proposed antenna has a very small size (20.25 × 8 × 1.27 mm³) compared with previous works. The measured and simulated results show a good agreement in terms of radiation pattern and impedance matching.

中文翻译：

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具有三个陷波特性的紧凑型超宽带缝隙天线

本文介绍了一种非常紧凑的超宽带（UWB）缝隙天线，该天线具有三个L形缝隙，可用于带缺口的特性。天线是使用新的阶梯式缝隙设计和制造的，阶梯形缝隙具有不同的尺寸，并集成在接地平面中，并由50Ω微带传输线激励。阶梯状狭缝用于最小化天线尺寸，并在2.65和11.05 GHz之间实现阻抗带宽，且电压驻波比（VSWR）小于2。阶梯状狭缝的长度等于四分之一波长，从而产生在所需的频率共振。在接地面上蚀刻了三个大小各异的L形槽，分别拒绝了C波段（3.7-4.2 GHz），WLAN（5.15-5.825 GHz）和X波段（7.25-7.75 GHz）的三个频段。可以通过改变L形槽的长度来控制陷波频率。拟议中的天线尺寸非常小（20.25×8×1.27 mm³）与以前的作品相比。测量和模拟结果在辐射方向图和阻抗匹配方面显示出良好的一致性。