Publications Internationales
Permanent URI for this collectionhttps://dspace.univ-boumerdes.dz/handle/123456789/13
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Item A compact double-inverted Ω-shaped dual-band patch antenna for WLAN/WiMAX applications(Frequenz : journal of RF-engineering and telecommunications, 2022) Djafri, Kahina; Mouhouche, Faiza; Dehmas, Mokrane; Challal, MouloudIn this study, a new compact dual-band antenna with overall size of 11 × 14.46 × 1.6 mm3 has been designed, fabricated and tested. The proposed antenna consists of two inverted Ω-shaped strips loaded with two different comb structures. The fist comb of six elements connected to the first Ω-shaped radiating branch is used to decrease the second band lower cut-off frequency and cover the intended WLAN and WiMAX applications. In order to cover the 2.45 GHz WLAN band and further reduce the antenna dimensions, a second comb structure of 14 elements is attached to the upper radiating branch. The fabricated antenna covers the frequency bands from 2.42 to 2.6 GHz and from 4.25 to 6.77 GHz with a reflection coefficient of |S 11| ≤ −10 dB. The antenna shows an omnidirectional radiation pattern in the H-plane and a monopole-like radiation pattern in the E-plane. The measured results agree well with the simulated ones which indicate that the proposed antenna is suitable to be used in the WLAN/WiMAX applicationsItem Compact dual-band fractal hexagonal ring monopole antenna for RFID and GSM applications(wiley, 2018) Djafri, Kahina; Challal, Mouloud; Azrar, A.; Dehmas, MokraneA novel compact dual‐band fractal antenna suitable for radio frequency identification (RFID) and GSM 1800 applications is developed and presented in this paper. This is achieved by adequate combination of three slotted hexagonal fractal rings which resulted in a significantly reduced size structure that can operate in the frequency ranges [0.895‐0.962 GHz] and [1.706‐1.856 GHz] that cover the frequency bands allocated to the intended applications. The proposed antenna has been fabricated and its reflection coefficient measured where a good agreement is observed with the simulated results.Item A compact superformula based ultra-wideband antenna shape with two notched bands(wiley, 2018) Mouhouche, Faiza; Azrar, A.; Dehmas, Mokrane; Djafri, KahinaIn this paper, a compact superformula ultra‐wideband (UWB) monopole antenna with dual band notches is proposed. The developed structure achieves UWB performance as well as a compact size of 20 × 26 × 1.62 mm3. Furthermore, to avoid interferences with WiMAX and satellite communication systems, dual notched band is obtained by engraving two co‐directional triangular split ring defects on the radiating element. The simulated and measured results show that the proposed antenna has an impedance bandwidth extending from 3.05 to 20 GHz with dual notched bands at [5.15‐5.68 GHz], and [7.15‐7.65 GHz] used in WiMAX and satellite communication, respectively. The proposed design realizes omnidirectional radiation pattern in H‐plane, and a dipole‐like pattern in E‐plane. The antenna exhibits an acceptable gain in the whole UWB range except at notched bands.Item Miniaturized Concentric Hexagonal Fractal Rings Based Monopole Antenna for WLAN/WiMAX Application(Scimago Journal & Country Rank, 2019) Djafri, Kahina; Challal, Mouloud; AKSAS, Rabia; Mouhouche, Faiza; Dehmas, MokraneIn this paper a new antenna design technique is introduced in order to achieve tri-band operation as well as antenna miniaturization. The technique consists of using two concentric first-iterative hexagonal rings connected to each other as a radiating patch fed with a Y-shaped micro-strip line. The proposed antenna operates at three fre-quency bands to cover 2.4/5.8 GHz WLAN bands and 3.5/5.5 GHz WiMAX bands applications. The numerical analysis and simulation are carried out with CST MWS. The measured return losses of the proposed antenna show good performance and good agreement with the simulated ones. Consequently the proposed antenna with compact size of 9.7 mm x 17 mm x 1.63 mm is well suited for wire-less applications.Item A Compact Dual-Band Planar Monopole AntennaUsing Fractal Rings and A Y-Shaped FeedingTransmission Line(DE GRUYTER, 2018) Djafri, Kahina; Challal, Mouloud; Romeu, JordiThis paper presents a novel design approach ofa compact dual-band monopole antenna with an overallsize of 18.9x13x1.6mm3. The proposed antenna is com-posed of a fractal ring shaped patch fed by a Y-shapedtransmission line on the top side of the substrate and asecond fractal ring along with a U-shaped ground planeon the bottom side. The second fractal ring, identical tothe radiating ring, is loaded and a rectangular slot isetched at the top side of the ground plane respectively,to achieve dual-band characteristic and improve theimpedance matching. The effect of standard ground-plane (SGP) of a laptop computer is incorporated in thedesign; the antenna is mounted on a SGP in order toinvestigate its performance. The antenna covers widelythe frequency bands of the WLAN 2.4 GHz (2.2–2.52 GHz)and WiMAX 3.5 GHz (3.32–4.35 GHz), and exhibits anomnidirectional radiation pattern in the H-plane and amonopole like radiation pattern in the E-plane. A goodagreement between the simulated and measured resultsindicates that the proposed dual-band antenna design issuitable for WLAN/WiMAX applications.Item A compact ACS-fed tri-band microstrip monopole antenna for WLAN/WiMAX applications(Advanced Electromagnetics, 2018) Djafri, Kahina; Challal, Mouloud; Dehmas, Mokrane; Mouhouche, Faiza; Aksas, RabiaThis paper proposes a novel small asymmetric coplanar strip (ACS) fed tri-band monopole antenna for WLAN and WiMAX applications. To tune and create multiple resonant frequencies, the exciting strip of monopole antenna is connected to two different arms which are a J-shaped directed toward the asymmetric ground plane and an open stub. The proposed monopole antenna with a total size of 14.6 x17.5 mm2 is fabricated and tested. The measured results indicate that the antenna has impedance bandwidths for 10-dB return loss reach about 500 MHz (2.01-2.52 GHz), 230 MHz (3.48-3.71 GHz) and 1.2GHz (5.59-6.72 GHz) which cover widely the 2.4/5.8 GHz WLAN bands and the 3.5GHz WiMAX band. The simulated radiation patterns of the proposed antenna at the three resonant frequencies have a dipole-like radiation pattern in both E-and H-Planes. The compact size, the simple structure and good radiation performances of the proposed antenna makes it well-suited forthe intended applicationsItem Design and evaluation of an antenna applicator for a microwave colonoscopy system(IEEE, 2019) Guardiola, Marta; Djafri, Kahina; Challal, Mouloud; Gonzalez Ballester, Miguel A.; Fernandez-Esparrach, Gloria; Camara, Oscar; Romeu, JordiItem Design and fabrication of a novel quadruple-Band monopole antenna using a U-DGS and open-Loop-Ring resonators(2017) Boutejdar, Ahmed; Challal, Mouloud; Bennani, Saad Dosse; Mouhouche, Faiza; Djafri, KahinaIn this Article, a novel quadruple-band microstrip patch antenna is proposed for the systems operating at quad-band applications. The antenna structure is composed of modified rectangular patch antenna with a U-shaped defected ground structure (DGS) unit and two parasitic elements (open-loop-ring resonators) to serve as a coupling-bridge. The proposed antenna with a total size of 31×33 mm2 is fabricated and tested. The measured result indicates that the designed antenna has impedance bandwidths for 10 dB return loss reach about 180 MHz (4.4–4.58 GHz), 200 MHz (5.4–5.6 GHz), 1100 MHz (7.2–8.3 GHz), and 700 MHz (9.6–10.3 GHz), which meet the requirements of the wireless local area network (WLAN), worldwide interoperability for microwave access (WiMAX), C and X bands applications. Good agreement is obtained between measurement and simulation results