New technique to drive the central frequency and to improve bandwidth of EBG structures

In this paper, a parametric study was done to find out the superstrat influence on locating the central frequency of the band gap. The present work compares the standard mushroom like with the EBG structures which are located between the substrate and the superstrat. The main motivation is to present a theoretical contribution by comparing the equations describing the central frequency of the band gap. In that way, this work investigates a new proposed design to shift the central frequency of the forbidden band to a low frequency, by inserting meandered lines to connect each part of the unit cell, which give an added capacitance to the EBG structures, in order to reach a low profile and lightweight EBG structure. The band gap was recognized by computing the transmission coefficient S21 resorting to the suspended line method (SLM).info:eu-repo/semantics/publishedVersio

Shifting the half wave dipole antenna resonance using EBG structure

In this paper, the main motivation is to introduce a new behavior of the electromagnetic band gap (EBG) structures, it is a significant shifting the resonance frequency down of the dipole antennas, this very interesting and useful technique led to low profile, in addition to performance enhancement of dipole antennas, either on return loss or radiation pattern. Also among this EBG structure an investigation on specific absorption rate (SAR) is shown. The used dipole antenna is resonating around 3.5GHz (part of 4G bands), then by using this technique we could shift the working frequency of the same dipole antenna to 2.8GHz worldwide interoperability for microwave access (WiMAX), this new resonance is 80% lower compared with the normal resonance without any structure. The principle of this new technique still valid with other frequency, depending on the frequencies that we would like to shift the working frequency between.info:eu-repo/semantics/publishedVersio

Enhanced low profile, dual-band antenna via novel electromagnetic band gap structure

This paper presents a dual-band, low profile antenna with reduced specific absorption rate (SAR) for mobile handset applications. Here, dual-band operation is obtained by combining a printed dipole antenna (initially resonating at 4.3 GHz) with EBG mushroom-like structures loaded with circular slots (CS). The final structure operates at 3.44 GHz (additional band required for LTE Advanced LTE-A) and 4.5 GHz (for Smartphone WLAN applications) with improved bandwidth and reflection coefficient (350-MHz around 3.5 GHz with −26 dB, and 330 MHz around 4.5 GHz with −30 dB). Finally, a dosimetry study of the proposed printed dual-band dipole antenna is presented and verifies an SAR reduction from 9 W/Kg to 1.41 W/Kg compared to the same antenna without any loading structure, and from 3.98 W/Kg to 1.41 W/Kg compared to a standard EBG mushroom-like structure.The authors gratefully acknowledge the Erasmus scholarship support provided by the Erasmus Mundus EU-MARE NOSTRUM Program.info:eu-repo/semantics/publishedVersio

A new hybrid method for mutual coupling minimization of an antenna array

In this paper, a simultaneous application of geometric modification on patch elements and electromagnetic band gap (EBG) electromagnetic bandgap structures (hybrid method) has been suggested for 3.5 GHz wireless communication applications, to minimize the mutual coupling between radiating elements of microstrip array antennas. The suggested EBG slotted structure is composed of a one square ring and three squares placed on Rogers RO3010 having 10.2 and h=1.27 mm which presents respectively its dielectric constant and thickness. In this approach, the patch elements are geometrically modified, while also employing EBG structures, formed by four EBG cells, placed between the array elements at a near distance. The modification of the geometry of the antenna and the introduction of EBG reduces the mutual coupling of an array antenna with approximately 33 dB on the one hand and improves the antenna gain by approximately 0.43 dB on the other hand. Initially, slots are introduced in the patch geometry and then four EBG unit cells are inserted between two patches, operating at 3.5 GHz. The antenna array design parameters were optimized

A Compact Design for Dual-band Implantable Antenna Applications

This paper presents the development of a dual-band antenna working in the Industrial, Scientific, and Medical (ISM) band (902 – 928 MHz, 2.4 – 2.5 GHz). The proposed antenna is compact, has a frequency-independent response between the lowest and the highest frequency, has a small size of 6 x 6 x 2.54 mm3. This design does not use any via or defected ground plane making the antenna very useful for this kind of application