Advanced Electromagnetics https://www.aemjournal.org/index.php/AEM <div class="hometabscontainer"> <div style="float: left;"> <table style="height: 287px;" width="158"> <tbody> <tr> <td valign="top" align="left"><br> <a href="https://aemjournal.org/images/aem_cover_new.png"><img class="img-responsive" style="border: 0px;" src="https://aemjournal.org/images/aem_cover_mini_new.png" alt="" width="150"></a> <p style="text-align: center;"><strong style="text-align: center;">ISSN: 2119-0275</strong></p> </td> </tr> </tbody> </table> </div> <br> <h2><span style="color: #336699;">Publish with impact and global reach!</span></h2> <p><strong>Open Access</strong>&nbsp;–&nbsp;<em>Advanced Electromagnetics</em> is free from all access barriers, allowing for the widest possible global dissemination of your work, leading to more citations.<br><strong>Comply with archiving policies</strong>&nbsp;– authors can deposit&nbsp;<em>any&nbsp;</em>version of their manuscript in&nbsp;<em>any</em>&nbsp;required repository or archive, or post articles to their personal or institutional website.&nbsp;<br> <strong>Retain copyright</strong>&nbsp;– authors retain the copyright to their own article; you are free to disseminate your work, make unlimited copies, and more.</p> <img class="img-responsive" src="https://aemjournal.org/images/indexing.png" alt="" width="583" height="122"></div> en-US <p>Authors who publish with this journal agree to the following terms:</p><ol><li style="text-align: justify;">Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a <a target="_blank">Creative Commons Attribution License</a> that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.</li><li style="text-align: justify;">Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.</li><li style="text-align: justify;">Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See <a target="_blank">The Effect of Open Access</a>).</li></ol> contact@aemjournal.org (AEM Editorial Team) contact@aemjournal.org (AEM Support Team) Fri, 07 Feb 2020 03:29:28 -0500 OJS 3.1.1.4 http://blogs.law.harvard.edu/tech/rss 60 Size Miniaturized Coaxial Probe Fed Antenna for Multiband Applications https://www.aemjournal.org/index.php/AEM/article/view/1152 <p class="BodyTextKeep" style="page-break-after: auto;"><span style="font-size: 10.0pt;">A novel coaxial cable-fed antenna with a combination of L-shaped elements is proposed for multiband applications. The obtained resonances at different frequency bands are realized by adding L-shaped strips with different lengths to the antenna geometry. The antenna is printed on a low-priced FR-4 substrate with overall size of 14×14×1.6 mm<sup>3</sup>. Experimental results indicate the coverage of 1.32, 1.80, 2.34, 3.30, 3.66, 4.26, 5.28, 7.68, 8.1, 9.72 and 10.38 GHz, compatible with L-band, WLAN, WiMAX, C-band, ITU 8 GHz, and X-band. Suitable radiation properties, multiband functionality, desirable gain values and agreement of simulated and measured results confirm the suitability of the proposed structure for multiband communication applications.</span></p> B. Heydarpanah, C. Ghobadi, J. Nourinia, P. Beigi, M. Majidzadeh ##submission.copyrightStatement## https://www.aemjournal.org/index.php/AEM/article/view/1152 Sat, 09 May 2020 11:46:42 -0400 On the coupling of forward and backward slow waves supported by the waveguide configuration of a dielectric sandwiched between two plasma slabs https://www.aemjournal.org/index.php/AEM/article/view/1368 <p>We derived a general equation governing the spectra of electrostatic surface plasmons supported by a waveguide structure of two identical plasma slabs separated by a dielectric medium. The plasma slabs are parallel, homogeneous, and have finite thicknesses. The geometry under consideration supports two surface plasmon modes, which we investigated numerically for Polyethylene $\varepsilon_d=2.25$ and vacuum $\varepsilon_d=1$ as central regions. With vacuum as a central region, the two surface plasmon modes become coupled and merge into the well known single mode of quasi-static frequency $\omega=0.707\omega_{\rm p}$. The surface plasmon modes in the presence of a Polyethylene are decoupled and remain nondegenerate over the whole range of $kd$. Therefore, the two plasmon modes propagate independent of each other with distinct quasi-static resonance frequencies, namely, a backward wave with $\omega=0.707\omega_{\rm p}$ corresponding to a single plasma-vacuum interface and a forward wave with $\omega=\frac{\omega_{\rm p}}{\sqrt{3.25}}=0.55\omega_{\rm p}$ corresponding to a single plasma-dielectric interface. Increasing the central region width is found to introduce a delay in reaching the quasi-static resonance frequencies. The effect of collision is to down shift the mode frequencies for long wavelengths and also to down shift the quasi-static frequencies.</p> E. Yasin, A. AlKhateeb, F. Rawwagah, A. Abuzir ##submission.copyrightStatement## https://www.aemjournal.org/index.php/AEM/article/view/1368 Fri, 01 May 2020 11:21:39 -0400 Design of Plasmonic NOT Logic Gate Based on Insulator – Metal – Insulator (IMI) waveguides https://www.aemjournal.org/index.php/AEM/article/view/1376 <p>&nbsp;&nbsp; In this work, all-optical plasmonic NOT logic gate was proposed using Insulator-Metal-Insulator (IMI) plasmonic waveguides Technology. The proposed all-optical NOT gate is simulated and realized using COMSOL Multiphysics 5.3a software. Recently, plasmonic technology has attracted high attention due to its wide applications in all-optical signal processing. Due to its highly localization to metallic surfaces, surface plasmon (SP) may have huge applications in sub wavelength to guide the optical signal in the waveguides which results in overcoming the diffraction limit problem in conventional optics. The proposed IMI structure is consist of a dielectric waveguides plus metallic claddings, which guide the incident light strongly in the insulator region. Our design consists of symmetric nano-rings structures with two straight waveguides which based on IMI structure. The operation of all-optical NOT gate is realized by employing the constructive and destructive interface between the straight waveguides and the nano-rings structure waveguides. There are three ports in the proposed design, input, control and output ports. The activation of control port is always ON. By changing the structure dimensions, the materials, the phase of the applied optical signal to the input and control ports, the optical transmission at the output port is changed. In our proposed structure, the insulator dielectric material is glass and the metal material is silver. The calculated contrast ratio between (ON and OFF) output states is 3.16 (dB).</p> H. F. Fakhruldeen, T. S. Mansour ##submission.copyrightStatement## https://www.aemjournal.org/index.php/AEM/article/view/1376 Tue, 07 Apr 2020 06:22:26 -0400 Optimization of the Method of Auxiliary Sources by the Genetic Algorithm for electromagnetic scattering problem https://www.aemjournal.org/index.php/AEM/article/view/1304 <p>In this paper, we propose to apply a technique of optimization of the convergence of the auxiliary sources method (MAS) for the problems of electromagnetic diffusion by a perfectly conducting and infinite obstacle. This technique is based on the use of the genetic algorithm (GA). Previous studies have shown that the convergence of the MAS solution depends on many parameters such as the number of auxiliary sources and the auxiliary distance between the real surface of the cylinder and the fictitious surface, and so on. The solution is obtained for a good choice of these parameters. In this article, the genetic algorithm is chosen to facilitate the choice of MAS parameters.</p> S. Hidouri, T. Aguili ##submission.copyrightStatement## https://www.aemjournal.org/index.php/AEM/article/view/1304 Sun, 22 Mar 2020 11:17:03 -0400 A Design of MIMO Prototype in C-Band Frequency for Future Wireless Communications https://www.aemjournal.org/index.php/AEM/article/view/1333 <p>The main challenges of MIMO design for future wireless communication is size reduction which leads to more mutual coupling. This paper deals with this problem in order to mitigate the impact of mutual coupling by proposing four elements MIMO prototype each one having a dual polarized patch rectangular microstrips. The idea is to insert annular rectangular opened one ribs in front of each microstrip and in corresponding to circular ring slot etched has etched in the ground. The advantage of such slot is to obtain regular radiation pattern distributed around device body. The four elements with eight ports are incorporated on 67×139 mm<sup>2 </sup>PCB with FR-4 dielectric layer. The single antenna is simulated CST.STUDIO 2019 resulting an operated frequency of 6.23 GHz with a band of 850 MHz (5.81-6.66) GHz at -10 dB. The fabrication MIMO system prototype is tested to show its measurement results which are match the simulated results. All results confirm of that proposed MIMO prototype which is operated at C-band frequency which is very important for future wireless applications.</p> N. M. K. Al-Ani, O. A. S. Al-Ani, M. F. Mosleh, R. A. Abd-Alhameed ##submission.copyrightStatement## https://www.aemjournal.org/index.php/AEM/article/view/1333 Sun, 22 Mar 2020 07:09:34 -0400 Validity of Improved MTL for Effective Length of Counterpoise Wires under Low and High-Valued Lightning Currents https://www.aemjournal.org/index.php/AEM/article/view/1383 <p>In this paper, an efficient modeling approach called improved MTL is used to predict effective length of counterpoise wires considering both ionization and dispersion of soils. This paper consists of two parts. At first part, validity of the model for computing effective length of counterpoise wires considering only soil ionization is investigated. The simulation results show that the improved MTL-based effective length of counterpoise wire are in good agreement with the existing formulae. Application of this modeling approach to include ionization and dispersion effects simultaneously (both-affected soil) is carried out in the second part. The simulation results show that in both-affected soils, the effective length with respect to only-ionized soils, is decreased especially in highly resistive soils under slow-fronted currents. This makes inclusion of both effects financially important in designing counterpoise wires.</p> S. R. Ostadzadeh ##submission.copyrightStatement## https://www.aemjournal.org/index.php/AEM/article/view/1383 Sat, 21 Mar 2020 15:49:50 -0400 Dual Band Filter-Antenna with Fixed Low Band and Frequency-Agile High Band for Wireless Communications https://www.aemjournal.org/index.php/AEM/article/view/1272 <p class="BodyTextKeep" style="page-break-after: auto;"><span style="font-size: 10.0pt;">This work proposes a design of compact filter-antenna with fixed and frequency-agile bands for wireless communications and cognitive radio (CR) systems. The filter-antenna is realized by attaching a bandpass filter with an independent fixed band and a tunable band to a UWB antenna. The dual bandpass filter consists of a folded open loop resonator loaded with single varactor diode at a suitable location to achieve</span> <span style="font-size: 10.0pt;">reconfigurability operations for the high band while the low band remains fixed at 4.5 GHz. A reconfigurable broadband frequency range of 3.2 GHz from 7.8 to 4.6 GHz is achieved for the high band by changing the capacitance of the varactor from 0.16 to 2.25 pF, respectively. A prototype of the filter-antenna is fabricated and measured at a selected capacitance of 0.6 pF to verify the simulation results. Good agreements between simulated and measured results are obtained. </span></p> H. A. Atallah ##submission.copyrightStatement## https://www.aemjournal.org/index.php/AEM/article/view/1272 Sat, 21 Mar 2020 12:40:43 -0400 A Compact Wide Bandpass Filter for Satellite Communications with Improved Out-of-Band Rejection https://www.aemjournal.org/index.php/AEM/article/view/1323 <p>This paper presents a compact C-band bandpass filter with improved out-of-band rejection. It consists of a symmetric three-pole parallel coupled line microstrip loaded with complementary split ring resonators (CSRRs) and slot resonators. Enhancements regarding the filter responses are obtained by etching these two parasitic shapes successively. When, CSRRs are introduced in the ground plane, exactly in the back of the transmission line of 50 -Ohms , improvements on the filter selectivity level are achieved. Whereas, the slot resonator elements are implemented on the feed line to permit the suppression of the second harmonics. To reduce the second harmonics of 11:1-13GHz, the parasitic elements are both combined, widen the filter rejection of 5:81%. The surface current distribution together with the equivalent circuit are also studied in order to demonstrate the slots and the CSRRs effect parameters on the behavior of the proposed filter. A prototype of the optimal filter is fabricated and measured.Theory and experiment results prove the validity of the new design procedure.</p> B. Ait Ahmed, A. Naghar, O. Aghzout, A. Vazquez Alejos, F. Falcone ##submission.copyrightStatement## https://www.aemjournal.org/index.php/AEM/article/view/1323 Fri, 20 Mar 2020 14:10:12 -0400 High Order Relaxation Methods for Co-simulation of Finite Element and Circuit Solvers https://www.aemjournal.org/index.php/AEM/article/view/1245 <p>Coupled problems result in very stiff problems whose char- acteristic parameters differ with several orders in magni- tude. For such complex problems, solving them monolithi- cally becomes prohibitive. Since nowadays there are op- timized solvers for particular problems, solving uncoupled problems becomes easy since each can be solved indepen- dently with its dedicated optimized tools. Therefore the co-simulation of the sub-problems solvers is encouraged. The design of the transmission coupling conditions between solvers plays a fundamental role. The current paper ap- plies the waveform relaxation methods for co-simulation of the finite element and circuit solvers by also investigating the contribution of higher order integration methods. The method is illustrated on a coupled finite element inductor and a boost converter and focuses on the comparison of the transmission coupling conditions based on the waveform iteration numbers between the two sub-solvers. We demon- strate that for lightly coupled systems the dynamic iterations between the sub-solvers depends much on the inter- nal integrators in individual sub-solvers whereas for tightly coupled systems it depends also to the kind of transmission coupling conditions.</p> J. D. Nshimiyimana, F. Plumier, C. Ndagije, J. Gyselinck, C. Geuzain ##submission.copyrightStatement## https://www.aemjournal.org/index.php/AEM/article/view/1245 Fri, 20 Mar 2020 09:47:39 -0400 A Multi-Band U-Strip and SRR Loaded Slot Antenna with Circular Polarization Characteristics https://www.aemjournal.org/index.php/AEM/article/view/1183 <p class="BodyTextKeep" style="page-break-after: auto;"><span style="font-size: 10.0pt;" lang="EN-US">A compact multiband circularly polarized slot antenna is proposed here. An F-shaped microstrip feedline is used to excite the square slot antenna loaded with a U-shaped strip and a split ring resonator (SRR) to generate three circularly polarized bands at 1.5 GHz, 2.75 GHz and 3.16 GHz. A meandered slot is used in the feedline and the U-strip to improve the axial ratio bandwidth (ARBW). The meandered feedline excites the slot to produce resonance at 2.5 GHz. This resonance along with that of the F-shaped feed, loaded SRR and U-strip combine to give rise to three circularly polarized bands which can be tuned depending on the feed, SRR and U-strip dimensions. The orientation of the F-shaped feed decides the sense of polarization of the three circularly polarized bands of the proposed antenna. The proposed antenna is fabricated on a substrate of FR4 material with dimensions 50 x 50 x 1.56 mm3. The antenna is prototyped and measured in terms of impedance bandwidth, ARBW, gain and efficiency. The simulated and measured results show reasonably good agreement.</span></p> P. M. Paul, K. Kandasamy, M. S. Sharawi ##submission.copyrightStatement## https://www.aemjournal.org/index.php/AEM/article/view/1183 Fri, 20 Mar 2020 09:17:39 -0400