Miniaturized reconfigurable tri‐polarization metantenna based on characteristic mode analysis with high‐aperture efficiency

Abstract

This article presents a miniaturized reconfigurable tri‐polarization metantenna with compact size of 0.58 λ0× 0.58 λ0× 0.04 λ0 (λ0 is the free space wavelength referring to the antenna center frequency). Metantenna means the metasurface is directly used as the antenna radiator aperture instead of an accessory. The metantenna is formed by miniaturized windmill like units, which is evolved from square patch units based on characteristic mode analysis, and 46% size reduction is achieved. Two PIN diodes are introduced into the feeding microstrip for switching among tri‐polarization. The measured −10 dB impedance bandwidths are 24.6% (3.24–4.15 GHz) and 24.1% (3.26–4.05 GHz) for circular polarization (CP) and linear polarization (LP), respectively. The measured overlapped 3 dB axial ratio (AR) bandwidth is 15% (3.4–3.95 GHz). The measured peak gains are 5.15 dBi, 5.21 dBic, and 5.25 dBic for LP, left hand (LH) CP and right hand (RH) CP, respectively. The aperture efficiency is 77.3%, 78.5%, and 79.1% for LP, LHCP, and RHCP, respectively. The measured AR beamwidth (BW) of LHCP in XZ‐plane and YZ‐plane is 192° and 174°, respectively, the measured ARBW of RHCP in XZ‐plane and YZ‐plane is 201° and 166°, respectively. The developed metantenna has the following advantages: broadband 3 dB AR bandwidth, wide ARBW > 166°, least PIN number (tri‐polarization with 2 PIN), and high‐aperture efficiency.

Wideband and low profile multipolarization reconfigurable antenna based on metasurface

“…19,24,26 The design in Tran et al 19 obtains a wide operating bandwidth of 25.6% but only works in CP modes, with a 7.3-dBic peak gain. The antenna in Huang and Wen 24 achieves one LP and two CP modes with an operating bandwidth of 24% and 15%, respectively, and a peak gain of 5.2 dBi/c. The work in Chen et al 26 can switch between two LP and two CP modes and realize a high peak gain, but with a narrow operating bandwidth of 18% and 10%, respectively.…”

“…There offers a comparison with other MTS polarization reconfigurable antennas reported in Tran and colleagues. 19,24,26 The design in Tran et al 19 obtains a wide operating bandwidth of 25.6% but only works in CP modes, with a 7.3-dBic peak gain. The antenna in Huang and Wen 24 achieves one LP and two CP modes with an operating bandwidth of 24% and 15%, respectively, and a peak gain of 5.2 dBi/c.…”

“…In Tran et al, 19 the transmission type nonuniform MTS antenna, with CP reconfigurability, obtains a 27% overlapped impedance bandwidth and a profile of 0.05 λ0 is designed. Moreover, a transmission‐type tri‐polarization reconfigurable antenna based on MTS has been presented in Huang and Wen 24 . Varying the current flow on the feeding microstrip by two PIN diodes, it achieves LP, left‐hand circular polarization (LHCP), and right‐hand circular polarization (RHCP) modes, with a compact size, a working bandwidth of 15%, and a low profile of 0.04 λ0.…”

“…Compared to conventional polarization reconfigurable antennas, the antenna based on metasurface (MTS) has acceptable balanced performances in broadband, high gain, and low profile, rapidly causing much attention. [19][20][21][22][23][24][25][26][27] Further, the polarization reconfigurable MTS antenna can follow up the position of the MTS and be classified into the transmission and reflection type, while placing the MTS upper or below the radiator, respectively. When the incident wave launches onto the transmission type MTS, the polarization of the transmissive wave will be changed.…”

A Low-Profile Broadband Metasurface Antenna With Polarization Conversion Based on Characteristic Mode Analysis

“…Although CMA was used for the analysis, the paper mentioned did not consider the effects caused by the slot structure and did not analyze the results of modal weighting coefficient (MWC). In [17], a windmill-shaped metasurface unit was proposed to realize a reconfigurable tri-polarized antenna, and the 3 dB ARBW of 15% was obtained. The proposed metasurface structure was analyzed by using the modal significance and characteristic currents in CMA, but the principle of achieving CP was not analyzed in depth.…”