Compact-Size Low-Profile Wideband Circularly Polarized Omnidirectional Patch Antenna With Reconfigurable Polarizations

In this article, a dual‐band and wideband omnidirectional circularly polarized (CP) antenna based on the vanadium dioxide (VO2) is investigated. The operating bandwidth of such an antenna can be regulated by altering the outside temperature (T), which is attained by the insulator‐metal transition of VO2. The omnidirectional CP antenna is based on a loop antenna‐dipole model, which is composed of four tilted metal and VO2 resonant units that are loaded around a cuboid and a feeding network for broadening bandwidth. The simulated results show that when T = 50°C (State I), the 10‐dB impedance bandwidth is 45.7% (1.67‐2.66 GHz), and the 3‐dB axial ratio (AR) bandwidth is 40% (1.9‐2.85 GHz). When T = 80°C (State II), the 10‐dB impedance bandwidth is 13.8% (1.62‐1.86 GHz), and the 3‐dB AR bandwidth is 21.8% (1.68‐2.09 GHz). In order to further characterize the concept of the proposed antenna, the related parameters of such an antenna are studied using simulation software HFSS.

Section: Simulated Resultsmentioning

confidence: 99%

A dual‐band and wideband omnidirectional circularly polarized antenna based on VO₂

Liu

Huang

Zhang

et al. 2019

“…Compared with antennas, which are switched by PIN diodes in ref. , the application of gravity field regulation costs lower energy. In addition, in comparison with antennas based on VO 2 adjusted by temperature in ref., the antenna is easier to realize.…”

Section: Introductionmentioning

confidence: 99%

A novel tailored coplanar waveguide circularly polarized antenna controlled by the gravity field

Huang

Zeng

Liu

et al. 2019

In this article, a tailored coplanar waveguide (CPW) circularly polarized (CP) antenna is designed, whose operating band can be adjusted in a large range by the gravity field through rotating the antenna vertically. Due to the fluidity of liquid metal mercury, which is packaged in the antenna's glass containers, when the antenna is rotated, mercury will lead to different metal resonant units in different directions under the influence of gravity. This antenna utilizes CPW whose metal reflective surface and the main radiating patch are on the same side of the dielectric substrate. The dielectric substrate is made of FR4, and the metal radiation patch and the metal reflective ground are made of copper. Two metal branches separated from the main radiation patch are connected to the main radiating patch by a glass container. To verify concept of the design, equivalent prototypes have been fabricated and measured. The measured results are roughly consistent with simulated results within a reasonable error range. The measured results show that when the antenna turns 90° counterclockwise along the x‐axis (state I), the 10‐dB return loss bandwidth is 13.5% (4.54~5.2 GHz), and the 3‐dB axial ratio (AR) bandwidth is 13.8% (4.5~5.17 GHz). When the antenna turns 90°clockwise along the x‐axis (state II), the 10‐dB return loss bandwidth is 23% (3.73~4.7 GHz), and the 3‐dB AR bandwidth is 23% (3.73~4.7 GHz) within the antenna operating range. In the cases of two different working states, the proposed antenna can effectively cover the 5G communication band.

“…In general, there exist 3 common ways for designing an omnidirectional CP antenna. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] In reference, 1,2 the antenna is inherently circular polarized and excited by a single feed, which has been created based on the zeroth-order resonance mode of epsilon negative transmission line.…”

Section: Introductionmentioning

confidence: 99%

“…In addition, the other designs of omnidirectional circular polarized antenna are reported in. [11][12][13][14][15][16][17][18] However, all the reported antennas have an omnidirectional circular polarized radiation pattern which covers a sector (eg, u 5 908) of azimuthal plane and is not suitable for space applications. To overcome this problem, antennas should have circular polarized pattern with 3608 coverage CP pattern radiation.…”

mentioning

confidence: 99%

Multi-petal antenna with omnidirectional circular polarized radiation

Nadi

Amirhosseini

2018

This article presented an omnidirectional circularly polarized antenna with simple and low‐cost configuration designed by combination of tilted loops for unmanned aerial vehicles such as drones and quadcopters. Length of each loop was 1 wavelength and was repeated around antenna axis with a specific angle. The 90° phase difference between 2 equally orthogonal polarized components was inherently provided by the loops without the need for exciting the loops 90° out of the phase. Symmetric configuration antenna yields circular polarization in both the azimuthal and elevation planes. The measured results showed that the 10‐dB impedance bandwidth was 390 MHz (ranging from 2.1 to 2.5 GHz) at the frequency of 2.45 GHz and the axial ratio bandwidth for < 3 dB was 400 MHz (ranging from 2.1 to 2.5 GHz). Moreover, this antenna had the right hand circular polarization with the difference between the measured left hand and right hand circular polarization gains being about 20 dB; the right hand circular polarized gain was about 1.4 dB.