A Novel Loop-Like Monopole Antenna With Dual-Band Circular Polarization

Abstract

Abstract-A novel loop-like monopole antenna with dual-band circular polarization (CP) for the reception of WiMAX and WLAN is designed and implemented in this paper. The antenna consists of a radiating patch which is composed of an annular-ring linked by a square ring over the corner and a ground plane with embedded rectangular slit. The broad impedance bandwidth is achieved based on a novel monopole structure which is the combination of two perturbed loops and the perturbation causes the generation of right-hand circular polarization (RHCP) at 3.52 GHz and left-hand circular polarization (LHCP) at 5.75 GHz. In addition, by embedding a rectangular slit on the ground, the impedance bandwidth can be greatly enhanced. The measured results show that the proposed monopole antenna has an impedance bandwidth of 3.65 GHz from 2.65 to 6.3 GHz, reaching the particularly broad bandwidth of 81.6%. Furthermore, the measured 3-dB axial ratio (AR) bandwidths are about 440 MHz at the lower band (3.52 GHz) and 220 MHz at the upper band (5.75 GHz). The radiation characteristics of the implemented antenna are also presented.

A Miniaturized Circularly Polarized Multiband Antenna for Wi-Max, C-band & X-band Applications

“…So in this case there is less chance of polarization mismatches, hence it is well suitable for communication devices [7,8]. stub [26], and monopole antenna with loops [27] are some other methods to achieve CP antenna. Fshaped antenna with a DGS [28] and hexagon-shaped antenna with a DGS [29] have also been used to achieve CP antenna by the authors.…”

A Small Disk-Coupled Circularly Polarized Microstrip Ring Antenna for Microwave Energy Harvesting

“…For instance, some references have used substrates with high dielectric constants to achieve the purpose of miniaturization. However, if dielectric plates with a high dielectric constant are directly employed, the serious surface wave effect will occur, resulting in the decrease of radiation efficiency and thus affecting the gain performance of the antenna [4][5][6]. Some scholars also dig holes on the surface of the patch.…”

A Printed Triangular Monopole With Wideband Circular Polarization

“…Most of the CP monopole antennas in the literature have relatively complex geometries with ground plane slots and stubs employed in the CP generation. In contrast, a simpler structure is proposed which achieves an AR bandwidth of 62% (1.42 GHz to 2.7 GHz) which is wider than [1][2][3][4][5][6][7][8][9][10][11]. The antenna has no slits or slots in the ground plane, thus mitigating the constraints of populating the ground plane with components or modules.…”

“…A moon-shaped radiator is used in [10] to achieve a wideband CP performance with AR<3 dB from 2.28 to 3.76 GHz. A monopole antenna comprising an annular-ring connected to a square loop as a radiator and a slotted ground plane is reported in [11] to have a dual-band CP with AR bandwidth of 12.5% from 3.3 to 3.74 GHz and 3.8% from 5.64 to 5.86 GHz. Most of the CP monopole antennas in the literature have relatively complex geometries with ground plane slots and stubs employed in the CP generation.…”