Comparative investigation of reflection and band gap properties of finite periodic wideband artificial magnetic conductor surfaces for microwave circuits applications in X‐band

Abstract

In this study, novel designs of artificial magnetic conductors (AMCs) for wideband operation are introduced. By using two techniques of the planar parasitic patches and stacked elements, AMC unit cells are achieved. The first design of the AMC unit cell is composed of four symmetric patches with two arms, which are coupled to a rhombic patch at the center. The second AMC design is configured of two stacked patches, which are connected together through the air spacing. The first and second AMC designs operate at the frequencies of 10.15 and 10.65 GHz with ±90° reflection phase bandwidths of 8 to 12.38 GHz (43.15%) and 8 to 12.90 GHz (46%), respectively, for X‐band operation. The proposed AMC unit cells present prominent features such as symmetric structures and wide bandwidths with distinct capabilities. To achieve an accurate evaluation of AMC performance, the reflection and band gap properties of the finite periodic AMC surfaces are investigated. The finite periodic arrays of the AMC reflectors are implemented and tested. The measured results show that they can be applied for wideband applications in microwave circuits and low profile antennas. The 15 × 15 AMC planar and stacked arrays under normal incidence operate at the frequencies of 9.89 and 10.25 GHz with the measured bandwidths of 7.85 to 12.02 GHz and 7.77 to 12.58 GHz, respectively. In addition, to identify the band gap properties of the finite periodic planar and stacked AMC arrays, the method of the suspended microstrip line is applied. For this purpose, the measured band gaps of the planar and stacked arrays include the ranges of 8.12 to 12.63 GHz and 7.81 to 12.10 GHz below −20 dB, respectively.

Radiation Properties Improvement of 1 × 4 Array of Wideband Printed Antenna Supported by AMC Surface for Vehicular MIMO Systems

“…It is well known that the artificial magnetic conductor (AMC) structures indicate similar properties like a perfect magnetic conductor with in‐phase reflection response whole an operating frequency. Based on this, multiple low‐profile antennas and mode prevention designs with AMCs are utilized to augment the distinguishing features (Barth & Iyer, 2016; Deng et al., 2017; Lee & Lee, 2016; Malekpoor, 2019; Malekpoor & Jam, 2016, 2018; S. Ghosh et al., 2014; Sievenpiper et al., 1999; X. Y. Liu et al., 2015; Yang et al., 2017). Among these works, a mushroom‐shaped AMC structure as a beneficial approach is usually applied for diverse arrangements to achieve the low‐profile structures with higher efficiency (Jam & Malekpoor, 2016b).…”

Accurate Characterization of Electromagnetic Band-Gap Structures

“…Surface waves occur on the interfaces between two dissimilar materials such as metal and free space; these waves are bound to the interface and decay exponentially into the surrounding materials. EBG periodic structures have high EM surface impedance that is capable of suppressing the propagation of surface waves and acting as an in-phase reflector (perfect magnetic conductors) within a certain frequency range [6,[9][10][11][12]. The specific electromagnetic properties of EBG materials motivate the researchers to extensively study applying its band-gap phenomena for practical uses in microwave [5,13] and sub-terahertz [14][15] applications.…”

Design and Modeling of Hybrid Uniplanar Electromagnetic Bandgap Power Planes for Wide-Band Noise Suppression on Printed Circuit Boards

“…Despite the advantages of UC-EBG structures, the compact design remains complicated due to the area occupied by the patches and horizontal traces. Although, there have been several researches on area reduction for the sophisticated UC-EBG structures [15]- [17], the researchers had primarily focused on reducing the area of the UC-EBG structure instead of bandwidth improvement efficiency.…”