Impedance bandwidth, multi-band, gain, and circular polarization (CP) are important characteristics of the microstrip antenna. In this paper, these characteristics have been highlighted by designing three different antenna structures. The proposed modified ground plane antenna consists of tilted G-shaped radiator (TGSR), which acts as a radiating element. The overall volume of the proposed antenna is 0.25λ0 × 0.2λ0 × 0.008λ0 (where λ0 is the free space wavelength of 1.5 GHz). The substrate used for fabricating the antennas is FR4. The Ant.I has multiband characteristics with four distinct frequency bands. However, Ant.II provides wide impedance bandwidth and also it has a single CP band, which covers the upper band of WLAN and WiMAX. Moreover, Ant.III (TGSR) exhibits two wide impedance bandwidths as well as two wide CP bands, supporting for WLAN, WiMAX, and X-band for satellite communication. The peak gains of Ant.I, Ant.II and Ant.III are about 5.5dBi, 6.6dBi, and 6.5dBic, respectively.

中文翻译：

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基于应用的微带天线演进：呈现宽带宽圆极化和多谐振特性

阻抗带宽、多频带、增益和圆极化 (CP) 是微带天线的重要特性。在本文中，通过设计三种不同的天线结构来突出这些特性。拟议的修改接地平面天线由倾斜的 G 形辐射器 (TGSR) 组成，它充当辐射元件。建议天线的总体积为 0.25λ0 × 0.2λ0 × 0.008λ0（其中 λ0 是 1.5 GHz 的自由空间波长）。用于制造天线的基板是FR4。Ant.I 具有多频段特性，具有四个不同的频段。但是，Ant.II 提供了较宽的阻抗带宽，并且它具有单个 CP 频段，覆盖了 WLAN 和 WiMAX 的上频段。此外，Ant.III (TGSR) 具有两个宽阻抗带宽和两个宽 CP 频带，支持 WLAN，WiMAX 和用于卫星通信的 X 波段。Ant.I、Ant.II和Ant.III的峰值增益分别约为5.5dBi、6.6dBi和6.5dBic。