Study and Design of Reconfigurable Antennas Using Plasma Medium Mohd Taufik Jusoh Tajudin

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Study and Design of Reconfigurable Antennas Using Plasma Medium Mohd Taufik Jusoh Tajudin Study and design of reconfigurable antennas using plasma medium Mohd Taufik Jusoh Tajudin To cite this version: Mohd Taufik Jusoh Tajudin. Study and design of reconfigurable antennas using plasma medium. Electronics. Université Rennes 1, 2014. English. NNT : 2014REN1S019. tel-01060295 HAL Id: tel-01060295 https://tel.archives-ouvertes.fr/tel-01060295 Submitted on 3 Sep 2014 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. ANNÉE 2014 THÈSE / UNIVERSITÉ DE RENNES 1 sous le sceau de l’Université Européenne de Bretagne pour le grade de DOCTEUR DE L’UNIVERSITÉ DE RENNES 1 Mention : Traitement du Signal et Télécommunications Ecole doctorale MATISSE présentée par Mohd Taufik JUSOH TAJUDIN préparée à l’unité de recherche I.E.T.R – UMR 6164 Institut d’Electronique et de Télécommunications de Rennes Université de Rennes 1 Thèse soutenue à Rennes le 04 avril 2014 Study and Design of devant le jury composé de : Mme. Paola RUSSO Reconfigurable Professeur, Università Politecnica delle Marche, Ancona, Italy / rapporteur Antennas Using M. Olivier PASCAL Professeur, Université de Toulouse, Toulouse, France / Plasma Medium rapporteur M. Christian PERSON Professeur, Institut Telecom/Télécom Bretagne, Rennes, France / examinateur M. Philippe POULIGUEN HDR, Ingénieur DGA-MI, Bruz, France / examinateur M. Olivier LAFOND Maitre de Conférences HDR, IETR, Université de Rennes 1, Rennes, France / co-directeur de thèse M. Franck COLOMBEL Maitre de Conférences HDR, IETR, Université de Rennes 1, Rennes, France / co-directeur de thèse M. Mohamed HIMDI Professeur, IETR, Université de Rennes 1, Rennes, France / directeur de thèse Acknowlegement Bismillahirahmanirahim, First of all I would like to render my entire appreciation to my respected supervisors, Prof.Mohamed Himdi,Assc.Prof.Olivier Lafond andAssc.Prof.Franck Colombel for their guidance,help and insight motivation throughout two and half years working with them at IETR.Their continuous support had helped me to excel in finishing my research work.Allof youhavebeenmyrolemodelsandinspiration. It is pleasure to acknowledge my gratitude to the reviewers,Prof.Paola Russo and Prof. Olivier Pascal for accepting my thesis work.Not to forget for the others juries, Prof. Christian Person and Eng.Philippe Pouliguen.The comments and suggestions before andduringmydefenseareveryusefultoimprove myworkinthe futureendeavors. I also would like to mention my thousand thank to Mr. Laurent Cronier and Mr. Christophe Guiton for helping me to come out with excellent antenna prototypes. The sweet memories when we were working together to complete my prototype will always remain in my heart.Thanks a ton to Mr.Jerome Sol and Dr.Laurent Le Coq for their excellent works in antenna measurements.The suggestions and ideas from both of you aremuch appreciated. To my office mates,Dr.Lilia Manach’,Jonathan Bor and Carole Leduc,thank you for your friendship,supports and help throughout my days at IETR.The sweet memories that we had shared are safely embedded in my heart and it will not be erased over time. Additional thank to Dr.Hamza who had introduced me to this excellent group.Not to forgettoDr.NgocTinh Nguyenforbeingmysilent advisor. Utmost,I would like to address my grateful feeling to my parents (Mr. Jusoh Tajudin and Mdm.Che Tom), parents’ inlaw (Dr.Jalal and Mdm.Yuha) for their belief in me andtheirprayers.Tomy siblings,thesupportand theprayerswillneverbe paidbyme. Words unable to describe how thankful I am to my wife Dr. Fariha Hanim for her unconditional support through the thick and thin and also to my beloved sons,Abdullah Aqil and Fawwaz Zaki.‘Mama,thanks for being there when I needed you.Abi will not beabletoattainthisPhdwithout yourexistenceby myside.’ Last but not least,I would like to pay my tribute to Ministry of Education of Malaysia andNationalDefense UniversityofMalaysiaforprovidingmethescholarship. ........speciallydedicatedtomybelovedwife,Dr FarihaHanim,ourgiftedsons,Abdullah Aqil,FawwazZakiandtomyhonorablefamily RESUMEENFRANÇAIS Résumé enfrançais Tabledesmatières 1.0 Introduction ......................................................................................................................i 2.0 Modélisationduplasma ....................................................................................................i 3.0 Réflecteurd’antennereconfigurable ..............................................................................iv a. Antenneàréflecteur circulaire ........................................................................................iv b. Antenneàréflecteurtriangulaire......................................................................................v 4.0 Antennaplasma ..............................................................................................................vi 5.0 SurfaceEquivalenteRadardesantennesplasmareconfigurables ................................viii 6.0 Conclusion ......................................................................................................................ix RESUMEENFRANÇAIS 1.0 Introduction Le plasma est le 4ème état de la matière qui est naturellement disponible.Le plasma diffère des métamatériaux qui ont une permittivité et une perméabilité négative. En effet, le plasma conserve une perméabilité positive alors que sa perméabilité est négative.C’est la principale caractéristique du plasma qui présente un intérêt pour la conception des antennes. De manière générale, le plasma se comporte comme un matériau conducteur et cette caractéristique peut disparaître lorsque le plasma n’est plus excité. Ce caractère reconfigurable du plasma est utilisé dans ces travaux pour la conception d’antennes. La caractéristique conducteur/non-conducteur du plasma est contrôlée électriquement et le plasma est utilisé soit comme un élément rayonnant,soit comme un réflecteur ou bien comme un absorbant. Dans certains cas, le plasma peut alorsremplacer avantageusementdesmatériauxmétalliques. La notion de plasma a été introduite en physique au début des années 20. Dans un premier temps, le plasma a été utilisé comme un élément rayonnant pour transmettre des signaux électromagnétiques.En 1919,le concept d’antenne plasma a été breveté par J. Hettinger.Les développements significatifs des plasmas ont démarré dans les années 60 lorsquecesderniersontétéintroduitsdansdessystèmesdecommunication. 2.0 Modélisation du plasma L’une des principales tâches de ces travaux concerne la caractérisation du plasma.Si la fréquence plasma et la fréquence de collision peuvent être estimées alors différentes zones de fonctionnement des antennes plasmas peuvent être identifiées. Dans ces travaux, le modèle du plasma a été défini en ce basant sur des mesures. La première mesure permet de déterminer la fréquence du plasma et la deuxième permet d’évaluer la fréquencedecollision. Pour déterminer ces caractéristiques,nous avons utilisé le dispositif suivant: Nous avons placé entre deux cornets suffisamment éloignés l’un de l’autre,d’une part un mur de plasma réalisé à l’aide de tubes néon et d’autre part une feuille de métal. On note que la feuille de métal est soit pleine,soit munie de fentes représentant l’espacement présent entredeuxtubesnéonadjacents(figure1). i RESUMEENFRANÇAIS (a) (b) Figure1–Photographiedumurdeplasma(a)Plasmaréaliséà l’aidede6 lampes fluorescentes enparallèles (lamesureaété faite avec 20lampesfluorescentes)et lemur métallique(b)munidefentes. La figure 2 montre le dispositif de caractérisation du plasma. La mesure du coefficientdetransmissionentrelesdeuxcornets aétéeffectuéedanscinq cas: - Enespacelibre(pasd’obstaclesituéentrelescornets). - Avecunmurmétallique pleinentrelesdeuxcornets. - Avecunmurmétallique munidefentesentreles deuxcornets. - Avecunmurdetubesfluorescents(plasma)excités entrelesdeuxcornets. - Avecunmurdetubesfluorescents(plasma)nonexcitésentrelesdeuxcornets. Lamesure acommencéavecaucunobstaclesitué entrelesdeuxcornets.Cecisertde référence.Dans les autres cas,un des obstacles décrits précédemment est disposé entre les deux cornets.La mesure du coefficient de transmission permet de comprendre les caractéristiquesduplasma. Plasma wall Transmitter (horn antenna) 100 100 Receiver (horn antenna) Figure 2 – Dispositif de mesure avec un mur de tubes fluorescents disposé entre deux cornets.Ladistanceentrelesdeuxcornetsestde 100 cm. ii RESUMEENFRANÇAIS Les résultats expérimentaux sont décrits sur la figure 3. Sur la figure 3a, on remarque qu’en dessous de 8 GHz,le coefficient de transmission est similaire lorsque qu’il n’y a pas d’obstacle (espace libre) ou lorsque l’on place un mur de tubes fluorescents nonexcités.On estime que la propagation des ondes est atténuée à partir de 7 GHz lorsque le mur de tubes fluorescents est excité (figure 3b).On en déduit que le plasma passe alors d’un état non conducteur à un état conducteur.Ce travail se focalise en dessous de cette fréquence caractéristique, où le plasma possède alors une permittiviténégative etsecomportecommeunmétalavecuneconductivitéfaible. 0 0 -5 S plasma OFF -5 S plasma ON 21 21 S free space -10 S free space
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