A Compact Unidirectional Wideband Step Slot Antenna over an Artificial Magnetic Conductor

In this letter, a novel broadband circularly polarisation (CP) wide-slot antenna with an artificial magnetic conductor (AMC) as the reflector is presented. The wide-slot antenna is composed of a knife-shaped radiator and an improved ground plane. A broadband CP characteristic can be achieved by slotting the ground plane to make it an asymmetric ground shape. However, the average gain of the wide-slot antenna is only about 3 dBic because of bidirectional radiation. An AMC reflector is adopted to enhance the gain of the wide-slot antenna without introducing a high profile similar to the PEC reflector. In addition, the four metal plates are vertically placed around the antenna to broaden the axial ratio (AR) bandwidth of the antenna with the AMC reflector. The measurement results show that the 3dB AR bandwidth of the proposed CP antenna is 32.4% (2.35GHz─3.26GHz), the average gain is 6.5dBic in the AR bandwidth and the value of VSWR in the AR bandwidth is less than 2. The size of the antenna is 0.84λ0× 0.84λ0× 0.13λ0 at the centre frequency of 2.805 GHz. The proposed antenna has a low profile, broad AR bandwidth and high gain, thereby being a good candidate for various wireless communication systems.

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A Low-Profile HF Meandered Dipole Antenna with a Ferrite-Loaded Artificial Magnetic Conductor

Applied Sciences ◽

10.3390/app11052237 ◽

2021 ◽

Vol 11 (5) ◽

pp. 2237

Author(s):

Oh Heon Kwon ◽

Won Bin Park ◽

Juho Yun ◽

Hong Jun Lim ◽

Keum Cheol Hwang

Keyword(s):

High Frequency ◽

Dipole Antenna ◽

Unit Cell ◽

Operating Frequency ◽

High Permeability ◽

Magnetic Conductor ◽

Artificial Magnetic Conductor ◽

Low Profile ◽

Compact Size ◽

Binary Genetic Algorithm

In this paper, a low-profile HF (high-frequency) meandered dipole antenna with a ferrite-loaded artificial magnetic conductor (AMC) is proposed. To operate in the HF band while retaining a compact size, ferrite with high permeability is applied to the unit cell of the AMC. The operating frequency bandwidth of the designed unit cell of the AMC is 1.89:1 (19–36 MHz). Thereafter, a meandered dipole antenna is designed by implementing a binary genetic algorithm and is combined with the AMC. The overall size of the designed antenna is 0.06×0.06×0.002 λ3 at the lowest operating frequency. The proposed dipole antenna with a ferrite-loaded AMC is fabricated and measured. The measured VSWR bandwidth (<3) covers 20–30 MHz on the HF band. To confirm the performance of the antenna, a reference monopole antenna which operates on the HF band was selected, and the measured receiving power is compared with the result of the proposed antenna with the AMC.

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Highly efficient artificial magnetic conductor enabled CPW fed compact antenna for BAN wearable applications

Frequenz ◽

10.1515/freq-2020-0115 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Maksud Alam ◽

Amber Khan ◽

Mainuddin ◽

Binod Kumar Kanaujia ◽

Mirza Tariq Beg

Keyword(s):

Coplanar Waveguide ◽

Split Ring Resonator ◽

Area Network ◽

Network Analyzer ◽

Magnetic Conductor ◽

Split Ring ◽

Artificial Magnetic Conductor ◽

Compact Antenna ◽

Resonant Modes ◽

Miniaturized Antenna

AbstractIn this paper a coplanar waveguide feed (CPW) monopole antenna backed with artificial magnetic conductor (AMC) structure for efficient radiation has been presented for off-body wearable applications. A split ring resonator (SRR) having thiner and longer lines to produce higher inductance and six splits with smaller gaps for high capacitance have been placed underneath CPW fed monopole to achieve resonance mode at a lower frequency. Higher values of inductance and capacitance produce resonant modes at relatively lower frequencies resulting in highly miniaturized antenna. The desired −10dB S11 bandwidth has been optimized firstly, by tuning/optimizing flow of surface currents with the help of several slots/slits and later by realizing AMC reflector with the help of full ground backed foam. The proposed antenna covers 2.45 GHz industrial, scientific and medical (ISM) band body area network (BAN) application and posses good front to back ratio (FBR) and thereby low and acceptable values of specific absorption rate (SAR). The proposed antenna has been designed and simulated using Ansys high frequency structured simulator and tested using vector network analyzer and anechoic chamber. The simulated and measured results well agree with each other.

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