3 research outputs found
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 β26 dB, and 330 MHz around 4.5 GHz with β30 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