A W-Shaped Antenna With Spatial Polarization Variation for Direction Finding

Choi, Sangjo; Sarabandi, Kamal

doi:10.1109/lawp.2018.2877451

Cited by 7 publications

(5 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, the fractional bandwidth with the degree of CP larger than 0.5 is 6.94%. This bandwidth, which is wider than 6.2 % from the similar antenna topology operating at 2.58 GHz, results from a low Q factor due to the high metallic loss in the IR range [46].…”

Section: Circularly Polarized Bowtie Antenna With Ingaassb Loadmentioning

confidence: 93%

Circularly Polarized Cross-Tapered Bowtie Antenna for IR Polarimetry

Choi

Sarabandi

2019

IEEE Access

Self Cite

View full text Add to dashboard Cite

We propose a novel cross bowtie antenna using phase-shift lines to realize circular polarization (CP) in the infrared (IR) spectrum. The CP antenna consists of a vertical, a horizontal antenna, and two elliptical loops connecting adjacent tips of the antennas to create a 90 • phase shift. The phase-shift lines are conceived to realize a single terminal of the antenna where a detecting material can be mounted and enable the detecting material to fully utilize the field enhancement from the antenna. In full-wave simulations, a nanometer-scale low-bandgap semiconductor, i.e., indium gallium arsenide antimonide (InGaAsSb) capable of detecting IR wave is loaded at the antenna terminal and the antenna structure is designed to achieve CP absorption at 180 THz. The antenna includes a transmission line-based impedance matching structure to compensate for the reactance of the InGaAsSb semiconductor load. To verify the CP detection of the antenna near 180 THz, we numerically show a higher field enhancement value and absorption rate in the antenna terminal in a specific CP case when the antenna is illuminated with incident waves with various polarization states. Also, we design 2 × 1 and 2 × 2 antenna arrays using the CP antennas connected with metallic traces and show that the CP absorption at 180 THz is maintained. Finally, an illustration of a focal plane array based on the proposed CP cross bowtie antennas coupled with the InGaAsSb for a full Stokes polarimeter is presented.INDEX TERMS Infrared antenna, nanoantenna, circularly polarized antenna, stokes vector, infrared full Stokes polarimetry.

show abstract

Section: Circularly Polarized Bowtie Antenna With Ingaassb Loadmentioning

confidence: 93%

Circularly Polarized Cross-Tapered Bowtie Antenna for IR Polarimetry

Choi

Sarabandi

2019

IEEE Access

Self Cite

View full text Add to dashboard Cite

show abstract

“…The schematic of the proposed retroreflector is shown in Figure 1d , where a FPGA‐based hardware system is used as the external controller to individually address each micromotor and control the orientation of each meta‐atom mechanically. The general steps to achieve dynamically adaptive retroreflection are: first, the incoming direction of the incidence is detected by an array of direction‐finding antennas; [ 45 , 46 ] second, the incidence direction is sent to the computer to calculate the required phase distribution for retroreflection; third, such phase distribution is converted to specific voltage for controlling the orientation of each meta‐atom. More details of the realization of dynamically adaptive retroreflection system can be found in Section S3 of the Supporting Information.…”

Section: Principle and Element Designmentioning

confidence: 99%

Angular‐Adaptive Reconfigurable Spin‐Locked Metasurface Retroreflector

et al. 2021

View full text Add to dashboard Cite

Metasurface retroreflectors, which scatter the incident electromagnetic wave back to incoming direction, have received significant attention due to their compelling advantages of low profile and light weight compared with conventional bulky retroreflection devices. However, the current metasurface retroreflectors still have limitations in wide-angle and omnidirectional operations. This work proposes a high-efficiency, wide-angle, reconfigurable, and omnidirectional retroreflector composed of spin-locked phase gradient metasurface with a thickness of only 5.2 mm or 0.07 operating wavelength. The reflection phase of constituent meta-atoms can be controlled dynamically and continuously by altering their orientation states through individually addressing each mechanically rotational meta-atom, whereas the reflection handedness is kept the same as incidence. Therefore, adaptive and arbitrary momentum can be imparted to the incident wave, providing high-efficiency retroreflection over a wide continuous range from −47°to 47°. Moreover, such high-performance retroreflection is extended to omnidirectional level, enabling great degrees of freedom that are unavailable by previous researches. As a proof of concept, a retroreflective metasurface is fabricated and experimentally demonstrated at microwave frequencies. The proposed thin thickness, high efficiency, and reconfigurable metasurface retroreflector can be extended to other frequencies that may offer an untapped platform toward reconfigurable spin-based retroreflection devices for electromagnetic signal processing.

show abstract

“…Although some of them have very wide CP coverage, the radiation patterns are not isotropic. Very few works have been reported that have attempted to achieve quasi-isotropic radiation patterns and wide CP coverage at the same time [27][28][29][30][31][32]. However, [28][29][30] have a directional radiation pattern for each polarization sense, i.e., RHCP radiation in one semi-sphere and LHCP in the other semi-sphere.…”

Section: Introductionmentioning

confidence: 99%

“…Very few works have been reported that have attempted to achieve quasi-isotropic radiation patterns and wide CP coverage at the same time [27][28][29][30][31][32]. However, [28][29][30] have a directional radiation pattern for each polarization sense, i.e., RHCP radiation in one semi-sphere and LHCP in the other semi-sphere. Thus, they are not orientation-insensitive and not very suitable for IoT applications.…”

Section: Introductionmentioning

confidence: 99%

A Fully-Printed 3D Antenna With 92% Quasi-Isotropic and 85% CP Coverage

Klionovski

Liao

et al. 2022

IEEE Trans. Antennas Propagat.

View full text Add to dashboard Cite

Internet of things (IoT) applications require orientation insensitive wireless devices to maintain stable and reliable communication. For those reasons, antennas providing a wide quasi-isotropic and circular polarization (CP) coverage are very attractive. However, achieving a wide quasi-isotropic and CP coverage simultaneously is challenging. In this work, we show that properly designed sloped dipoles on a 3D structure can maximize the CP coverage (theoretically up to 100%) even with equal-phased feed to the dipole elements. We derive the conditions and present the design graphs for the optimum slope angle for the dipole elements on a 3D hexagonal-shaped package to achieve a wide quasi-isotropic and CP coverage simultaneously. Based on the proposed theory, a practical antenna has been designed and fabricated using additive manufacturing. The measured results demonstrate a 7dBisotropy of 92% and a CP coverage of 85%, which matches well with the predicted results from the theoretical analysis and full-wave simulations.

show abstract

A W-Shaped Antenna With Spatial Polarization Variation for Direction Finding

Cited by 7 publications

References 13 publications

Circularly Polarized Cross-Tapered Bowtie Antenna for IR Polarimetry

Circularly Polarized Cross-Tapered Bowtie Antenna for IR Polarimetry

Angular‐Adaptive Reconfigurable Spin‐Locked Metasurface Retroreflector

A Fully-Printed 3D Antenna With 92% Quasi-Isotropic and 85% CP Coverage

Contact Info

Product

Resources

About