Low profile quad‐beam circularly polarised antenna using transmissive metasurface

Abstract

This paper presents a high efficiency and low profile quad‐beam circularly polarised transmitarray antenna using metasurface. In order to improve the aperture efficiency, the small unit cell is employed to obtain the beam forming since the gain of multi‐beam is higher and the feed antenna suitable for low profile transmitarray is selected. To further improve the aperture efficiency, the cells with high transmittance are located at the centre of metasurface to increase the transmission efficiency since the electric fields of the low profile transmitarray are more concentrated on the centre of metasurface than those of the high profile transmitarray. The unit cell of metasurface is stacked by optimising with equivalent circuit analysis and generalised sheet transition conditions that can confirm a multi‐layer performance easily. The principle of superposition was used to easily calculate the phase set required for quad‐beam forming. The designed metasurface is 17 × 17 array of four‐layer unit cells of 0.25λ0 × 0.25λ0 size at 5.8 GHz. The finally designed antenna with circularly polarised quad‐beam has the peak gain of 12.1 dBic at 5.72 GHz, and the aperture efficiency and 1 dB gain bandwidth were found to be 30.7% and 3.5%∼5.5% at four beams, respectively.

Computational Polarimetric Imaging Using Two-Dimensional Dynamic Metasurface Apertures

“…The current trends in the design of Huygens' metasurfaces (HMSs), which are planar arrays of balanced electric and magnetic polarizable particles (meta-atoms) of subwavelength size are presented in [32]. Various metasurface-based antennas have also been proposed for wireless applications [33]- [36].…”

Single-Pixel Polarimetric Direction of Arrival Estimation Using Programmable Coding Metasurface Aperture

“…Polarization is an important property of wavefronts with a great potential in various application scenarios such as wireless communication [1][2][3][4][5][6][7] , radar [8][9][10][11] , and imaging [12][13][14] . Because of the reduced multipath and antenna orientation constraints, dual-polarization and circular polarization are often suitable selections in wireless communication applications [1][2][3][4][5][6][7] .…”

“…Polarization is an important property of wavefronts with a great potential in various application scenarios such as wireless communication [1][2][3][4][5][6][7] , radar [8][9][10][11] , and imaging [12][13][14] . Because of the reduced multipath and antenna orientation constraints, dual-polarization and circular polarization are often suitable selections in wireless communication applications [1][2][3][4][5][6][7] . Target polarization properties are analyzed in remote sensing and synthetic aperture radar (SAR) applications in 8,9 , while airborne and spaceborne radar platforms include polarization information discussed in 10,11 .…”

Multi-State Circularly Polarized Antenna Based on the Polarization Conversion Metasurface With Gain Enhancement

“…Circularly polarized antennas are prominent in communication systems due to the flexibility in the arrangement of antennas at both trans-receiver side and also reduce the losses occurring due to the Faraday rotation effects [1]. On the other hand, a CP antenna is advantageous for the positional freedom of the receiver [2], [3]. In recent years, metasurface antennas have been used to reduce the antenna profile [4], enlarge the operating band [5], [6], full-space wave control [7], [8] and improve the directivity of the antenna [9], [10].…”