RESEARCH ARTICLE Design of circular patch antenna with a high gain by using a novel artificial planar dual-layer metamaterial superstrate Abdessalam El Yassini 1 | Lahcen Aguni 1 | Saida Ibnyaich 1 | Samira Chabaa 2 | Abdelouhab Zeroual 1 1 Department of Physics, Cadi Ayyad University, Marrakesh, Morocco 2 Industrial Engineering Department, Ibn Zohr University, Agadir, Morocco Correspondence Abdessalam El Yassini, Department of Physics, Cadi Ayyad University, 40000 Marrakesh, Morocco. Email: abdessalam.elyassini@edu.uca.ac.ma Abstract This study presents a new dual-layer metasurface structure proposed to enhance the performance of a circular patch antenna. A novel unit cell planar metasurface is characterized by nearly equal enhanced effective permeability and permittivity ε r ffi μ r > 1 at the resonant frequency. In addition, a 5*5 array of these unit cells are used as a superstrate over a circular patch antenna which is fed by 50 Ω micro- strip line and operating at 2.45 GHz for improving the antenna performance. The patch antenna gain is increased by creating an in-phase electric field area on the top surface of the metasurface. The obtained results showed that the maximum gain of the antenna increased from 2.31 dBi to 7.5 dBi. A 30% increase in the band- width is also remarked. The proposed antenna with metasurface occupies an overall volume of 1.01λ g ×1.01λ g ×0.025λ g . The simulation analysis and measured results were performed using the microwave studio, high frequency structure simulator software, and vector network analyzer. The proposed antenna prototype has been fabricated. The measured results indicate that the antenna has a good impedance matching in the desired operating band (2.37-2.49 GHz) with the resonant fre- quency of 2.44 GHz which make the proposed antenna appropriate for microwave applications. KEYWORDS artificial planar metamaterial superstrate, circular patch antenna, gain enhancement, ISM 2.45 GHz, metasurface 1 | INTRODUCTION In recent years, microstrip antennas (MA) have been one of the most interesting radiators in the wireless communication systems as mobile and satellite due to their great advantages: planar structure, simple and ease of fabrication, low profile, and compatibility with integrated circuit technology. The basic geometry of the microstrip patch antenna consists of a metallic patch printed on a grounded substrate. 1,2 However, the basic geometry has two major disadvan- tages, low gain and narrow bandwidth, which lead limit to the use of microstrip patch antennas for a wide range of applications. Furthermore, recent increases in the transmis- sion and reception of wireless communication have created a need for wideband and high-gain antennas. Enhancing the gain of an antenna has the advantages of increasing trans- mission distance and decreasing the power consumption of the transmitter. Several approaches reported in the literature studied the improvement of the gain that includes: antenna array and antenna configuration. 3-5 However, the more the number of antenna elements is higher, the more the complexity and Received: 14 February 2019 Revised: 7 August 2019 Accepted: 7 August 2019 DOI: 10.1002/mmce.21939 Int J RF Microw Comput Aided Eng. 2019;e21939. wileyonlinelibrary.com/journal/mmce © 2019 Wiley Periodicals, Inc. 1 of 16 https://doi.org/10.1002/mmce.21939