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Touhami N.A.,Abdelmalek Essaadi University | Yahyaoui Y.,Abdelmalek Essaadi University | Zakriti A.,Abdelmalek Essaadi University | Bargach K.,Abdelmalek Essaadi University | And 3 more authors.
Progress In Electromagnetics Research C | Year: 2014

In this paper, the design and analysis of a compact coplanar waveguide-fed ultra wideband pentagon antenna are presented. To achieve ultra wideband performance, two modifications are introduced. The first one is to remove a small fan angle on each side of the ground plan, and the second one is to modify the sharp of the patch in the width. The optimal dimensions can be achieved by a parametric analysis. The antenna design exhibits a very wide operating bandwidth of 16.7 GHz with a return loss better than 10 dB in the frequency range from 4.46 GHz to 21.14 GHz. The gain of the proposed antenna is 6.3 dBi. This antenna configuration will be useful for UWB indoor application as it is easy to fabricate and integrate with RF circuitry. All simulations in this work were carried out by using the electromagnetic software CST.

Tribak A.,INPT Institute National des Postes et Telecommunications | Zbitou J.,Faculte Polydisciplinaire de Khouribga FPK | Mediavilla A.,University of Cantabria | Touhami N.A.,Abdelmalek Essaadi University
Progress In Electromagnetics Research C | Year: 2013

In this paper, we develop a small-sized mode converter with high performance, high conversion efficiency and instantaneous bandwidth as high as 55%. This mode converter transforms energy from the TM01 first high-order mode towards the fundamental TE11 circular waveguide mode The proposed structure increases the free spurious operating bandwidth in comparison with the existing results in literature. An X/Ku-bands experiment prototype unit was designed, ensuring practical return losses better than 28 dB and insertion losses less than 0.1 dB (conversion efficiency > 98:8%) within the entire frequency bandwidth ranging from 9.25 GHz to 16.25 GHz The presented architecture offers useful features such as very wide bandwidth, small size, easy achievement as well as excellent performance, which makes it very suitable for High-power microwave (HPM) sources that generate the TM01 circular waveguide mode. In these cases, the TE11 mode is needed since it has a convergent radiation pattern able to drive conventional antennas. Moreover, this compact concept is fully scalable to any millimeter frequency band.

Tribak A.,INPT Institute National des Postes et Telecommunications | Mediavilla A.,University of Cantabria | Zbitou J.,University Hassann 1 ler | Cano J.L.,University of Cantabria
International Journal of Microwave and Optical Technology | Year: 2014

A compact differential phase shifter structure that exhibits both full and easy mechanical manufacture is presented. It consists of a rectangular waveguide loaded with single ridge sections terminated by a unique H plane step widening to stand dimensions. Two prototypes of 90° and 180° differential phase shifters with reference to an empty waveguide of the same length were designed and tested for the WR75 waveguide band. In both cases the differential phase shifter exhibits a maximum measured phase error of ±2.5° and ±3.5° respectively, with return losses better than 24 dB and insertion losses lower than 0.06 dB over a >40% bandwidth, which represents state achievement for non-dielectric loaded waveguide circuits. Furthermore, this structure is well suited for H-plane millimetre-wave integration. © 2014 IAMOT.

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