Design of single-feed circularly polarized (CP) microstrip antenna is proposed in this article. The design employs the concept of E-shape patch with inclined fractal defected ground structure (IFDGS), which can improve the impedance bandwidth, gain, and axial ratio (AR) bandwidth. The excellent enhanced impedance bandwidth, axial ratio bandwidth, and gain are achieved by an inclined E-shaped fractal etched on the ground plane. The parameter studies of the E-shaped IFDGS are given to illustrate the way to obtain CP radiation. The third iterative IFDGS is fabricated on easily available FR4 substrate with a size of 0.494 λ0 × 0.494 λ0 × 0.019 λ0 (λ0 is the wavelength in free space at 3.624 GHz). The measured results verify the simulated results and show good agreement. The proposed antenna shows an impedance bandwidth of 12.7% at a centre frequency of 3.47 GHz and 3-dB AR bandwidth for this band is 2.39% at a centre frequency of 3.626 GHz. The measured peak gain for the proposed antenna is found as 8.1 dBi. The proposed antenna can be suitable for mobile WIMAX operation (IEEE 802.16e-2005 standard), wireless communication in CA-band and FCC.

中文翻译：

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面向CA波段应用的倾斜分形缺陷地基圆极化天线分析与设计

本文提出了单馈圆极化（CP）微带天线的设计。该设计采用带有倾斜分形缺陷接地结构（IFDGS）的E形贴片概念，可以提高阻抗带宽、增益和轴比（AR）带宽。优异的增强阻抗带宽、轴比带宽和增益是通过蚀刻在接地平面上的倾斜 E 形分形来实现的。给出了E形IFDGS的参数研究来说明CP辐射的获取方式。第三次迭代 IFDGS 是在尺寸为 0.494 的容易获得的 FR4 基板上制造的λ0× 0.494λ0× 0.019λ0(λ0是自由空间中 3.624 GHz 的波长）。实测结果验证了模拟结果并显示出良好的一致性。建议的天线在 3.47 GHz 的中心频率处显示出 12.7% 的阻抗带宽，在 3.626 GHz 的中心频率处，该频段的 3-dB AR 带宽为 2.39%。建议天线的测量峰值增益为 8.1 dBi。所提出的天线可适用于移动WIMAX操作（IEEE 802.16e-2005标准）、CA波段和FCC无线通信。