DESIGN AND ANALYSIS OF MULTIBAND SLOTTED OCTAGONAL FRACTAL ANTENNA

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1 Iteatioal Joual of Advaced Reseach i Electoics ad Commuicatio Egieeig (IJARECE) DESIGN AND ANALYSIS OF MULTIBAND SLOTTED OCTAGONAL FRACTAL ANTENNA NEHYA CHAUDHARY, SONIKA SINDHIYA, K.K TIRPHATI (A.K.G.E.C) Depatmet of Electoics ad Commuicatio U.P. Techical Uivesity,Luckow,Idia Abstact- Slotted Octagoal Factal Ateal desigig fequecy 2.5 GHz, The small physical size ad multibad capability ae vey impotat i the desig of multibad ateas. Factals have uique popeties such as self-similaity ad space-fillig. The use of factal geomety i atea desig povides a good method fo achievig the desied miiatuizatio ad multi-bad popeties. I this commuicatio, a multi-bad atea based o a ew factal geomety is peseted. The poposed desig is a Octagoal shape factal atea. The simulated though IE3D softwae. It is woth oticeable that poposed shapes suits fo 2.5 GHz WLAN ad Bluetooth ( IEEE-2.11b/g std.),3.5 GHz WIMAX( IEEE-2.11y std.) std. The esults show that the poposed Cow shaped Factal Atea ca be used fo 2 GHz 5 GHz fequecy age. ove covetioal factal ateas. The commecially available simulatio softwae IE3D Micowave Studio has bee used fo the desig ad simulatio of the poposed micostip atea. Accodig to the esults, this ew factal atea is applicable i 2 GHz 5 GHz fequecy age ad the gai of this factal micostip atea is easoable i etie badwidth. I. INTRODUCTION Mode commuicatio systems equie ateas with moe badwidth ad smalle dimesio. Oe of the mai compoets of ultawidebad (UWB) commuicatio systems is a UWB atea. Customaily, widebad ateas eed diffeet atea elemets fo diffeet fequecy bads. If atea size is less tha a quate of wavelegth, atea will ot be iciet. Factal geomety is a vey good solutio to fabicate multi-bad ad low pofile ateas. Applyig factals to atea elemets allows fo smalle size, multibad ad boad-bad popeties. Thus, this is the cause of spead eseach o factal ateas i ecet yeas [1] [4]. Factals have self-simila shapes ad ca be subdivided i pats such that each pat is a educed size copy of the whole. The self-similaity of factals is the cause of multi-bad ad boad-bad popeties ad thei complicated shapes povides desig of ateas with smalle size. Factals have covoluted ad jagged shapes such that these discotiuities icease badwidth ad the ective adiatio of ateas. The spacefillig popety of factals leads to cuves which have log electical legth but fit ito a compact physical volume. [5] [9]. Seveal UWB atea cofiguatios based o factal geometies have bee ivestigated icludigkoch, Siepiski, Mikowski, Hilbet, Cato, ad factal tee ateas i ecet yeas. The umeical simulatio ad expeimetal esults of these ateas ae available i liteatue to date. I this commuicatio, a factal micostip atea is peseted. This ew factal geomety is based o a iteative octago. The huge badwidth is the mai advatage of this factal atea Fig. 1. geomety of Slotted octagoal subaay geeato This commuicatio is aaged i fou sectios. Desig of poposed atea is discussed i Sectio II. Simulated ad measued esults ae peseted i Sectio III,IV. II.ANTENNA DESIGN Fo micostip ateas, the width (W) ad legth (L) of the adiatig patch ad the ective pemittivity of the micostip stuctue ( e ) which suppot the opeatio at the equied esoat fequecy (o the fee-space wavelegth ca be desiged as follows, usig the fomulas give[14]. c W ( 1) 2 f ( 1) All Rights Reseved 214 IJARECE 41

2 Iteatioal Joual of Advaced Reseach i Electoics ad Commuicatio Egieeig (IJARECE) h w...(2) 135 cos 2 d do...(6) 2 (1) L c 2 f......(3) The aay facto may be expessed i the fom A^ F p 1 P jp11.36 si cos, P e P1 1...(7) Whee ( L.412h ( W.3).264 h...(4) W.25). h () si cos...(9) L L 2L ( 5) A covetioal micostip atea, havig squae adiatig patch, with patch dimesios L=32mm W = 32 mm, desiged to opeate at 2.5 GHz, the stadad fequecy fo wieless LAN. A pited cicuit boad (PCB) with the pemittivity = 4.4 (compaed to the commecial PCB, FR-4) is used as the dielectic substate placed o top of the goup plae to fom the micostip atea. The thickess of the substate is 1.6 mm. Thee ae seveal types of factal micostip patch ateas. The most well-kow factal patch atea is Siepiski patch atea such that the vaious types of it ae used geatly i telecommuicatio systems. The quadilateal ad hexagoal factal micostip ateas wee discussed i some papes. I iitial pocess of this poject, may desigs ad simulatios aepefomed ove factal patch ateas. The vaious types of quadilat-eal, petagoal ad hexagoal factal patch ateas ae cosideed ad fially the octagoal factal shape is selected because of its good pefomaces i badwidth ad gai. The stadad octagoal aays ae fomed by placig elemets i a equilateal tiagula gid. These aays ca also be viewed as co-sistig of a sigle elemet at the cete, suouded by seveal co c-etic eight elemet cicula aays. To ivestigate the desigs fo octagoal aays via a ecusive applicatio, we coside the eight-elemet cicula geeatig sub-aay of d 2 show i Fig. 1. Accodig to the octagoal po-peties, the iteio agle is 135 ad the exteio agle is 45.Thus we ca coclude The paamete is a scale facto that cotols the lageess of the aay with each ecusive geeatio applicatio ad P is the umbe of cocetic octagos i the aay. Theefoe, the total umbe of elemets with P octagos is N P (1) 4P P Fig. 2. Iteatios of the poposed factal geomety. The aay facto expessio may also be witte i the fom A^ F P Whee P jp1,, e P (11) All Rights Reseved 214 IJARECE 42

3 Iteatioal Joual of Advaced Reseach i Electoics ad Commuicatio Egieeig (IJARECE) 1.36 si cos si cos...( 12), If the expasio facto of the ecusive octagoal aay is assumed to be 1, the equatio is expessed i fom Fig. 3. Atea stuctue secod iteatio 1 j, A^ Fp, e......( 13) 1 The geometic costuctio of Fig 2 thee ae a thee shape fist factal shape stats with a octago, called the base shape, which is show i Fig. 2 (Base Shape). By addig aothe octago iside the base shape, the fist vesio of the ew factal geomety, show i Fig. 2 (Fist Iteatio) is ceated. The pocess is epeated i the geeatio of the secod iteatio which is also show i Fig. 2 (Secod Iteatio). I this commuicatio, the secod iteatio of the octagoal factal geomety is cosideed sice highe ode iteatios do ot make sigificat affect o atea popeties. III. SIMULATED RESULT Fo this atea, the legth of each side of octago is 2 cm. with patch dimesios L=32mm W = 32 mm, desiged to opeate at 2.5 GHz, the stadad fequecy fo wieless LAN. A pited cicuit boad (PCB) with the elative pemittivity = 4.4 (compaed to the commecial PCB, FR-4) is used as the dielectic substate placed o top of the goup plae fom the micostip atea. The thickess of the substate is 1.6 mm. Fig.4. The simulated S 11 fo the secod iteatio Afte completio of simulatio setup IE3D povides vaious atea paametes though its easily accessible i use gaphics fomat fo aalysis poit of view. The fig 4 epesets the simulated cuve of Retu Loss paamete (i db). As fa a feq. to be esoat feq, it must follow the ule of S 11-1 db. O this ule ou poposed Slotted Octagoal geomety atea povides multiple fequecy sample poit whee S 11-1.The same is also veified by VSWR cuve i VSWR 2). All Rights Reseved 214 IJARECE 43

4 Iteatioal Joual of Advaced Reseach i Electoics ad Commuicatio Egieeig (IJARECE) Retu loss ite ite1 TABLE 1 etu loss cuve fo all iteatio Feq. S 11-2 d - Ite. Feq. S 11-1 st - Ite. Feq. Basic shape Fequecy GH Z Fig.5. The Retu loss cuve fo all iteatio ite2 IV. MEASURED RESULT Atea chaacteistics ae measued usig the etwok aalyze. It is vey coveiet ad easy to obtai atea iput chaacteistics usig a etwok aalyze. The etu loss (S11) measuemet ca be obtaied fom this equipmet usig sigle pot calibatio. The expeimetal set up is show i Fig Feq(GHz) ite ite1 ite2 Fig.7. Testig of Complemetay slotted octagoal atea with Netwok aalyze (VNA) scee showig the Retu Loss plot Fig.6. The VSWR cuve fo all iteatio TABLE:2 Diffeece B/W Retu iteatio measued ad simulated loss cuve fo Secod Feq. Measued RL Feq. Simulated RL All Rights Reseved 214 IJARECE 44

5 Iteatioal Joual of Advaced Reseach i Electoics ad Commuicatio Egieeig (IJARECE) Physics ad Egieeig of millimete ad Sub Millimete Waves, vol.1, pp [5]. Rage B.J. Bao, 1994, factal ladscape 2294 available at [6]. Selva, P.T. Raghava, S.,211, A ovel compact CPW-fed octago shaped slot atea fo WLAN applicatio,wielesscommuicatio,vehicula Techology, Ifomatio Theoy ad Aeospace,& ElectoicSystem Techology,pp.1-4 Fig. 7. shows the stuctue of atea o the substate. V. CONCLUSION The Octagoal Factal Atea is obseved to possess mulitibad behavio [1, 2,11], ad it is pactical to chage the fequecy sepaatio as we wat. It is easy to foecast the atea s fequecy; theefoe, the Octagoal Factal Atea seems to be a iteestig cofiguatio fo use i applicatios whee multibad opeatio with a small ad chaged fequecy sepaatio is equied. Whe we eed moe tha two esoat fequecies, we ca use the moe iteated oes. Ad use the same way to coodiate evey squae s cicumcicle (R) to get the wated fequecies. V. REFERENCES [1]. Falcoe K. J., 199, Factal Geomety: Mathematical Foudatios ad Applicatios.New Yok:,Joh Wiley& Sos,Ic. New Yok. [2]. Giavittoio J. P., 23, Factals, MEMS, ad FSS electomagetic devices miiatuizatio ad multiple esoaces," Dissetatio, Uivesity of Califoia, Los Ageles. [3]. Giavittoio J. P.,Rahmat-Sammi. Y, 22, Factal Atea: A ovel miiatuizatio Techique ad Applicatio, IEEE Tasactios o Atea & Popagatio, vol.44, Issue: 1, pp2-36. [4]. Kavcheko F. ad A.A. Potapov, 21 New class of Atomic factal fuctios & thei applicatios, [7]. Wojciech J. Kzysztofik,MARCH 29, Modified Siepiski Factal Moopole fo ISM-Bads Hadset Applicatios IEEE Tasactios o Atea ad Popagatio, Vol. 57, o. 3. []. Aidi Mehdipou, 21, Iosif D. Rosca, Abdel-Razik Sebak, SFull-Composite Factal Atea Usig Cabo Naotubes fo Multibad Wieless Applicatios IEEE Ateas ad Wieless Popagatio Vol.9. [9]. Mahdi Naghshvaia Jahomi, Abolfazl Falahati, 211, Badwidth ad Impedace-Matchig Ehacemet of Factal Moopole Ateas Usig Compact Gouded Coplaa Waveguide, IEEE Tasactios o Atea ad Popagatio, Vol. 59, o.7. [1]. Amapeet Kau1, Niti Saluja2,J S Ubhi3,july 212 Desig Of Siepiski Gasket Multibad Factal Atea Fo Wieless Applicatios IOSR Joual of Electoics ad Commuicatio Egieeig (IOSRJECE) ISSN : Volume 2, Issue 3, PP [11]. Abolfazl Azai,MAY 211, SLOTTED OCTAGONAL FRACTAL ANTENNA IEEE Tasactios o Atea ad Popagatio, Vol. 59, NO. 5, [12]. R. L. Yadava1, M. Ram1 ad S. Das,21 Multibad Tiagula Factal Atea fo Mobile All Rights Reseved 214 IJARECE 45

6 Iteatioal Joual of Advaced Reseach i Electoics ad Commuicatio Egieeig (IJARECE) Commuicatios R L Yadav et. al. / Iteatioal Joual of Egieeig Sciece ad Techology Vol. 2(11), [13]. Sachi chauha,212,a desig of cow-shape factal patch atea Iteatioal Joual of Egieeig ad Iovative Techology (IJEIT) Volume 2, Issue 3. [14]. Costatie. A. Balais, 193 Atea Theoy, Aalysis ad Desig (Secod Editio) Joh Wiley & sos, Ic [15]. Wag Yog, Liu. Shaobi,2 A New Modified Cow Squae Factal Atea IEEE Tasactios o Atea ad Popagatio. All Rights Reseved 214 IJARECE 46