Abstract

A compact dual-band dual-mode and dual-polarized (DBDMDP) antenna based on an asymmetrical Y-shaped microstrip line feeding along with a square ring radiator is proposed. The structure is loaded with two pairs of L-strips to extend the lower mode bandwidth (center frequency f_c = 9.36 GHz). This section is employed to change an electromagnetic field distribution and achieve dipole-like omni-directional linearly polarized (LP) radiation. The asymmetrical Y-shaped microstrip line feeding section is used to realize patch-like directional circular polarization (CP) radiation for the higher mode (at f_c = 12.13 GHz). The measured results show that the 10-dB impedance bandwidths for the dipole mode and patch mode are equal to 730 MHz (7.72%, f_c = 9.45 GHz) and 1648 MHz (14.26%, f_c = 11.56 GHz), respectively, among which the 3 dB simulated axial ratio bandwidth of the patch mode is of 1280 MHz (10.74%, centre frequency of CP band f_CP = 11.92 GHz). The two modes’ maximum gains at f_c = 9.36 and 12.13 GHz are equal to 1.44 and 2.62 dBi, respectively. The maximum peak gain is of 3.32 dBi at frequency of 12.27 GHz. This single-feed patch antenna can be useful in wireless communication applications for its compact structure, considerable bandwidth, stable radiation pattern and polarization diversity.

中文翻译：

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具有极化分集的双频双模天线

摘要

提出了一种基于非对称 Y 形微带线馈电和方环辐射器的紧凑型双频双模双极化 (DBDMDP) 天线。该结构被加载有两对L-条的延伸的下模带宽（中心频率˚F _Ç = 9.36千兆赫）。该部分用于改变电磁场分布并实现类似偶极子的全向线性极化 (LP) 辐射。非对称 Y 形微带线馈电部分用于实现高模（f _c = 12.13 GHz）的贴片状定向圆极化 (CP) 辐射。测量结果表明，偶极子模式和贴片模式的 10-dB 阻抗带宽等于 730 MHz (7.72%, f_c = 9.45 GHz) 和 1648 MHz (14.26%, f _c = 11.56 GHz)，其中贴片模式的 3 dB 模拟轴比带宽为 1280 MHz (10.74%，CP 频带中心频率f _CP = 11.92 GHz）。两种模式在f _c = 9.36 和 12.13 GHz 时的最大增益分别等于 1.44 和 2.62 dBi。在 12.27 GHz 频率下，最大峰值增益为 3.32 dBi。这种单馈源贴片天线因其紧凑的结构、可观的带宽、稳定的辐射模式和极化分集而在无线通信应用中非常有用。