A novel wideband circularly polarized microstrip patch antenna (MPA) with multimode resonance is proposed in this letter. The TM _1/2,0 mode, the zeroth-order mode, and the TM _1,0 mode are excited by inserting the shorting pins underneath the driven patch and the parasitic patch. Therefore, a wide impedance bandwidth is achieved under triple-mode resonance. By sequentially rotating the triple-mode elements, a circularly polarized MPA is developed with a four-feed network. Additionally, four metallic side walls are employed to obtain desirable radiation performances. For demonstration, a prototype of the proposed antenna is fabricated and measured. The measured −10 dB impedance bandwidth is 96% (1.53–4.39 GHz) and 3 dB axial ratio bandwidth is 86% (1.74–4.36 GHz). Meanwhile, a low profile with the height of 0.037 λ ₀ ( λ ₀ is the wavelength in free space at the lowest operating frequency) is obtained. Such a wideband, low-profile, and circularly polarized antenna is very promising for modern wireless communication applications.

中文翻译：

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具有多模谐振的宽带圆极化微带贴片天线

本文提出了一种具有多模谐振的新型宽带圆极化微带贴片天线（MPA）。TM _{1 / 2,0}模式，零阶模式和TM _1,0通过在驱动的贴片和寄生贴片下面插入短路引脚来激发模式。因此，在三模谐振下可获得宽的阻抗带宽。通过依次旋转三模元件，可以形成带有四馈电网络的圆偏振MPA。另外，采用四个金属侧壁以获得所需的辐射性能。为了演示，制造并测量了所建议天线的原型。测得的−10 dB阻抗带宽为96％（1.53–4.39 GHz），3 dB轴向比率带宽为86％（1.74–4.36 GHz）。同时，高度为0.037的低剖面 λ ₀（ λ ₀是在最低工作频率下的自由空间中的波长）。对于现代无线通信应用，这种宽带，薄型且圆极化的天线非常有前途。