A Low-Profile Wideband Linear-to-Circular Polarization Conversion Slot Antenna Using Metasurface

Abstract

A new low-profile wideband linear-to-circular polarization conversion microstrip slot antenna based on a metasurface for C-band satellite communication applications is proposed in this paper. The metasurface basically consists of four unit cells with parasitic square cross gaps arranged in a 2 × 2 layout. By loading the metasurface on the microstrip slot antenna, linearly polarized (LP) waves from the source antenna are converted into circularly polarized (CP) waves. Then, by etching three more parasitic square cross gaps in the middle of the metasurface, enhanced impedance bandwidth and axial ratio bandwidth (ARBW) are achieved. Furthermore, an equivalent circuit and a phase analysis are presented to explain how a wide ARBW is realized by the metasurface. A final model with an overall size of 36 × 36 × 3.5 mm3 (approximately 0.65λ0 × 0.65λ0 × 0.06λ0 at 5.5 GHz) was designed and fabricated. The measured S11 bandwidth and 3 dB ARBW were 39.25% from 4.28 GHz to 6.37 GHz and 17.77% from 5.18 GHz to 6.19 GHz, respectively. As a result, the proposed antenna shows great potential for satellite communication applications due to its low profile and compact structure, wide impedance bandwidth, and wide axial ratio bandwidth.

Bandwidth Enhancement of Microstrip Patch Antenna Using Metasurface

“…In [15], an antenna with potential application in satellite communications was developed by coupling a metasurface to a microstrip antenna. The metasurface basically consists of four unit cells with parasitic square crossed gaps in an array of 2 × 2 elements.…”

“…The aim is to achieve an antenna that operates from 5.1 GHz to 7.2 GHz with high gain in the entire band. The proposed structure is easy to build, inexpensive and compact compared to most previous configurations [6], [11] and has a higher bandwidth compared to [13], [15]. The results of the studies show that the metasurface characteristics and the unit cell pattern change the antenna impedance resulting in the overlapping of the new resonant frequencies, which allow a measured fractional bandwidth of 45.4 % (5.1 -8.0 GHz).…”

Radar cross section reduction and gain enhancement of slot antenna using polarization conversion metasurface for X‐band applications

“…Metasurfaces (MS), which is the 2-D equivalent of metamaterials, are being utilized presently for various antenna applications. [4][5][6][7][8][9][10][11] Not only they are used to improve the antenna performance in terms of gain 4 and bandwidth (BW), 5 but they are also used for antenna parameter (polarization, frequency or pattern) reconfiguration 6 and converting the polarization state of an antenna from linear to circular. [7][8][9][10][11] They have also proved to play a crucial role in reducing the antenna RCS owing to their extraordinary electromagnetic behavior.…”

“…[4][5][6][7][8][9][10][11] Not only they are used to improve the antenna performance in terms of gain 4 and bandwidth (BW), 5 but they are also used for antenna parameter (polarization, frequency or pattern) reconfiguration 6 and converting the polarization state of an antenna from linear to circular. [7][8][9][10][11] They have also proved to play a crucial role in reducing the antenna RCS owing to their extraordinary electromagnetic behavior. 12 Initially, a combination of artificial magnetic conductors (AMC) and perfect electric conductors (PEC) structures was most commonly used for RCS reduction of antennas.…”

Ultra-Thin Metasheet for Dual-Wide-Band Linear to Circular Polarization Conversion With Wide-Angle Performance

“…The basic principle for polarization conversion performance is decomposing incident wave into two components, orthogonal to each other but having the same magnitudes and phase difference as ±90˚. This concept has been used in different types of LP-to-CP converters which have been reported using non-resonant [12][13][14] and resonant periodic structures [15][16][17][18][19][20][21]. For example, Euler et al reported frequency selective surface based polarization converter using a single layer of the substrate [15].…”