In this paper, two asymmetric co-planar waveguide (ACPW) fed circularly polarized (CP) zeroth-order resonance (ZOR) antennas (Antenna I and II) are presented using a composite right and left-handed transmission line (CRLH-TL) approach. By adding a stub on the left side of the ACPW ground and adjusting its length, circularly polarization property has been achieved in Antenna I. The simulated 3 dB axial ratio bandwidth (ARBW) of Antenna I is 1750 MHz (3.50–5.25 GHz). Next, the left side ground plane of Antenna I is further defected by etching a quarter wavelength slit to introduce a notch band (Antenna II). Antenna II has an extended 10 dB return loss bandwidth of 2200 MHz (3.28–5.48 GHz) with a band notch from 4.18–4.65 GHz that isolates the WiMAX and 5.2 GHz WLAN bands. ARBWs of 1080 and 870 MHz are achieved in the first and second band of Antenna II. The overlapping 3 dB ARBW and 10 dB return loss bandwidths of Antenna II in these two bands are 770 and 830 MHz, respectively.

中文翻译：

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基于圆极化 ACPW 馈电 CRLH-TL 的 ZOR 天线，具有带陷特性

在本文中，使用复合左右手传输线 (CRLH-TL) 提出了两个非对称共面波导 (ACPW) 馈电圆极化 (CP) 零阶谐振 (ZOR) 天线（天线 I 和 II）方法。通过在 ACPW 接地左侧添加短截线并调整其长度，天线 I 实现了圆极化特性。天线 I 的模拟 3 dB 轴比带宽（ARBW）为 1750 MHz（3.50-5.25 GHz）。接下来，通过蚀刻四分之一波长狭缝来进一步缺陷天线 I 的左侧接地平面以引入陷波带（天线 II）。Antenna II 具有 2200 MHz (3.28–5.48 GHz) 的扩展 10 dB 回波损耗带宽，带陷波从 4.18–4.65 GHz 隔离 WiMAX 和 5.2 GHz WLAN 频段。在 Antenna II 的第一和第二频段中实现了 1080 和 870 MHz 的 ARBW。Antenna II 在这两个频段中重叠的 3 dB ARBW 和 10 dB 回波损耗带宽分别为 770 和 830 MHz。