IPASJ Internatinal Jurnal f Cmputer Science (IIJCS) eb Site: ttp://www.ipasj.rg/iijcs/iijcs.tm A Publiser fr Researc Mtivatin... Email: editriijcs@ipasj.rg Vlume, Issue, December 4 ISSN 3-599 Design and Cmparative Analysis f Rectangular and Square Lg Peridic Array Micrstrip Patc Antenna OGHEROHO, E. P*., Fm, T.P. And Egga, M.Y Department f Pysics, University f Js,P.M.B 84, Js Plateau State, Nigeria ABSTRACT Tis paper described te design, simulatin and cmparative analysis f inset feed seven elements lg peridic micrstrip antenna at.5-3.5 GHz wit te aide f Agilent (ADS9).Te antennas were mdeled using micrstrip lines, te S and 3D parameters data fr bt sapes were cmpared. Te data is extracted frm te entum simulatin. Te prperties f te antennas suc as return lss, gain, iciency, pwer radiated, crss plarizatin and te beam widt ave been investigated and cmpared wit eac ter. A gain f 3.47dB using square ver te gain f.8db fr rectangular, directivity f 7.44dB t 7.9dB, iciency f 34 t 36 and resnant frequency f.75ghz and 3.35GHz respectively. Keywrds:- Square, Rectangular, Cmparative, Seven Element Inset Feed, Micrstrip.INTRODUCTION Micrstrip antenna as gain ppularity because f teir small size and ligt weigt. Hwever a limitatin f micrstrip antenna is te narrw bandwidt f te basic element. Te bandwidt f a basic patc element is usually -3%.Te bandwidt f te antenna is defined [3] as te range f frequencies, ver wic te perfrmance f te antenna wit respect t sme caracteristics cnfrms t a specific standard. Te bandwidt f te antenna depends n te patc sape, resnant frequency, dielectric cnstant and te tickness f te substrate. Te bandwidt f te antenna can be increased by reducing te substrate permittivity ( r) r increasing its tickness ().Hw ever tere are tw prblems assciated wit increasing te substrate tickness. One f te prblem is te radiatin and reactance assciated wit te feed junctin.as given by [4].Te secnd prblem is an increase in surface wave ects[3].in rder t avid te prblems, a number f different metds ave been investigated t imprve te bandwidt f te micrstrip antenna. Different tecniques t enance te bandwidt f micrstrip antenna ave been investigated. Mst f te wrk dne fr bandwidt enancement as been directed twards imprving te impedance bandwidt f te antenna element. Te bandwidt can be increased using multilayer substrate structure antenna, parasitic elements [4], nn-cntact feeding tecnique, different sapes slt [6]rt lg peridic tecnique by [7 and 4], wic we applied in tis researc.. Design f LPA Te design principle fr lg peridic requires scaling f te dimensins frm perid s tat perfrmance is peridic wit te lgaritm f frequency. Tis principle can be applied t an array f patc antennas. Te patc lengt (L), te widt () and te inset (I) are related t te scale factr τ by. Lm m I m L m m I m () If we multiply all dimensins f te array by τ its scales int itself wit element m becming element m+ element m+ becming element m+ etc. Tis self-scaling prperty implies tat te array will ave te same radiating prperties at all frequencies tat are related by a factr f τ. A single element f rectangular r square gemetry as swn in Figure, can be designed fr te lwest resnant frequency using transmissin line mdel []. f c ( L L) () Vlume Issue December 4 Page 7
IPASJ Internatinal Jurnal f Cmputer Science (IIJCS) eb Site: ttp://www.ipasj.rg/iijcs/iijcs.tm A Publiser fr Researc Mtivatin... Email: editriijcs@ipasj.rg Vlume, Issue, December 4 ISSN 3-599 ere 8 c 3 m / s (.3) (.64) L.4 (.58) (.8) (3) r r (4) Fr micrstrip antennas te cice f te widt f te patc radiatr is very imprtant. Small values f () result in lw antenna iciencies wile large () values lead t iger rder mdes. Te ptimum values f is r (5) Te resnant input resistance can be calculated frm R in ( y y ) ( G G cs y L (6) G I sin k w cs I sin cs 3 (7) k w sin cs G j sin cs 3 k L sin d (8) j Bessel unctin f te first kind rder zer Te caracteristic impedance f te line can be calculated frm Z 8 ln w w wen 4 w (9) w.393.667 w ln.444 wen w () Vlume Issue December 4 Page 8
IPASJ Internatinal Jurnal f Cmputer Science (IIJCS) eb Site: ttp://www.ipasj.rg/iijcs/iijcs.tm A Publiser fr Researc Mtivatin... Email: editriijcs@ipasj.rg Vlume, Issue, December 4 ISSN 3-599 Te values f L, and inset feed (I) can be calculated using te abve equatins. Tis value will be scaled int lg peridic element. Calculatin f te lengt and widt f rectangular and Square patc micrstrip antenna is given in table.te substrate used is FR4 wit dielectric cnstant f 4.7 and tickness f.6.te scaling factr τ =.5.Te lss tangent f te material is.9. Table : Calculated Parameters fr Seven elements Lg Peridic Antenna Number Element f Frequency(GHz) L() () L=(Square Patc) Im f.5 7.5 35.54 35.54 5.5 f.63 6.3 33.78 33.78 5. f3.75 4.98 3.3 3.3 4.4 f4.89 3.75 3.75 3.75 3. f5 3.4.57 9.3 9.3 3. f6 3.9.49 7.85 7.85.5 f7 3.35.45 6.5 6.5. Te circuit design was btained using te Agilent sftware 9(ADS) te scematics were btained using te micrstrip lines (MSUB, and MTEE) and te S parameters were simulated using te abve mentined parameters. Figure and 3 sw te diagram and te layut diagram fr te Rectangular and Square patc antennas. MSub S_Param SP Start=.5 GHz Stp=3.5 GHz Step=. GHz MSUB MSub H=.6 Er=4.7 Mur= Cnd=.E+5 Hu=.e+33 T=.3 TanD=.9 Rug= S-PARAMETERS VSR VSR VSR VSR=vswr(S) N =zin(s,prtz) TL7 TL TL4 TL =7.5 =4.98 =.57 =.45 L=35.54 L=3.3 L=9.3 L=6.5 TL8 TL TL3 TL9 MSABND_MDS Bend =.5 MTEE_ADS MTEE_ADS MTEE_ADS Angle=45 TL Tee TL5 TL Tee3 TL5 TL8 Tee6 TL M=.5 MTEE_ADS MTEE_ADS MTEE_ADS TL6 TL3 TL6 Tee =.65 Tee4 =.65 Tee5 =.65 =.65 =.65 =.65 =.65 =.65 =.65 3=.5 =.65 3=.5 =.65 3=.5 =.65 =.65 =.65 3=.5 TL 3=.5 TL4 3=.5 TL7 =6.3 =3.75 =.49 L=33.78 L=3.75 L=7.85 Term Term Num= Z=5 Om Vlume Issue December 4 Page 9
IPASJ Internatinal Jurnal f Cmputer Science (IIJCS) eb Site: ttp://www.ipasj.rg/iijcs/iijcs.tm A Publiser fr Researc Mtivatin... Email: editriijcs@ipasj.rg Vlume, Issue, December 4 ISSN 3-599 Figure : Circuit and Layut fr seven element rectangular LPA MSub S_Param SP Start=.5 GHz Stp=3.5 GHz Step=. GHz MSUB MSub H =.6 Er=4.7 Mur= C nd=.e+5 H u=.e+33 T=.3 TanD=.9 R ug= S-PARAMETERS TL7 =35.54 L=35.54 TL8 VS R VSR VSR VSR=vswr(S) N =zin(s,prtz) TL =3.3 L=3.3 TL TL4 =9.3 L=9.3 TL3 TL =6.5 L=6.5 TL9 MSABND_MDS Bend =.5 MTEE_AD S MTEE_ADS MTEE_ADS Angle=45 TL Tee TL5 TL Tee3 TL5 TL8 Tee6 TL M=.5 MTEE_ADS MTEE_ADS MTEE_ADS TL6 TL3 TL6 Tee =.65 Tee4 =.65 Tee5 =.65 =.65 =.65 =.65 =.65 L=.5 =.65 L=.5 =.65 3=.5 =.65 3=.5 =.65 3=.5 =.65 =.65 =.65 3=.5 TL 3=.5 TL4 3=.5 TL7 =33.78 =3.75 =7.85 L=33.78 L=3.75 L=7.85 Term Term Num= Z=5 Om Figure : Circuit mdeling diagram fr seven element square lg peridic antenna Figure 3: Circuit and Layut fr seven element rectangular LPA Vlume Issue December 4 Page 3
IPASJ Internatinal Jurnal f Cmputer Science (IIJCS) eb Site: ttp://www.ipasj.rg/iijcs/iijcs.tm A Publiser fr Researc Mtivatin... Email: editriijcs@ipasj.rg Vlume, Issue, December 4 ISSN 3-599.RESULT AND DISCUSSION Te simulated results f te input and utput return lss fr te seven elements passive lg peridic antenna is swn in te figures (5-) and te cmparative values n Table : fr te cmparative f te rectangular and square array sws a real distinct difference in teir parameters. Rectangular lg peridic array Micrstrip antenna: Te bradband antenna f seven element array swn n Figure,te simulatin using ADS9 sftware package [ ],te antenna exibit a 3.99GHz resnant frequency,gain and directivity f 7.6 and 6.38dB respectively wit iciency f.89%. Square lg peridic array Micrstrip antenna: tis exibit a resnant frequency f. Figure 4: Te Return Lss fr Rectangular and Square Lg Peridic Array Micrstrip Antenna Figure 5: Te utput Return Lss f Rectangular and Square Figure 6: Smit Cart fr te input impedance Vlume Issue December 4 Page 3
IPASJ Internatinal Jurnal f Cmputer Science (IIJCS) eb Site: ttp://www.ipasj.rg/iijcs/iijcs.tm A Publiser fr Researc Mtivatin... Email: editriijcs@ipasj.rg Vlume, Issue, December 4 ISSN 3-599 Figure 7: Te radiatin Pattern fr Rectangular and Square LPA Figure 8: Te E-c and E-crss f Rectangular and Square LPA Figure 9: Te 3D radiatin pattern fr rectangular and Square LPA Vlume Issue December 4 Page 3
IPASJ Internatinal Jurnal f Cmputer Science (IIJCS) eb Site: ttp://www.ipasj.rg/iijcs/iijcs.tm A Publiser fr Researc Mtivatin... Email: editriijcs@ipasj.rg Vlume, Issue, December 4 ISSN 3-599 Percentage 9 8 7 5 4 3 m5 THETA= -5. real(efficiency)=.38 Max m5 Percentage 9 8 7 5 4 3 m9 THETA= 4. real(efficiency)=.764 Max m9 8 4 - -4 - -8-8 4 - -4 - -8 - THETA THETA Figure : Efficiency fr Rectangular and Square LPA Table : Te Antenna Parameters fr Rectangular and Square Array 3.CONCLUSION Te seven elements lg peridic rectangular and square array as been designed and analyzed using Agilent electrmagnetic simulatr. Te results sw a little difference frm teir perfrmances in terms f resnating frequency.75ghz and 3.35GHz respectively,gain f.8db and 3.47dB wic is ig cmpare t tat f rectangular and directivity as well as pwer radiated, but wit 5% bandwidt and are bt icient in perfrmance. It can be deduced tat eac sape is apprpriate fr different purpses f wireless cunicatin applicatin. References [] Balanis, C.A., Antenna Tery Analysis and Design nd editin, jn illey & Sns Inc. New Yrk, 997. [] Cen H.M, Sze, J.Y, Lin, Y.F., A Bradband rectangular micrstrip Antenna wit a pair f U saped slts Micrwave and Optical tec.letters, Vl.7, n.5, Dec., pp369-37. [3] Grag, P.Bartia, P., I. Bal and A. Itlipibn..Micrstrip Antenna Design Handbk. Artec Huse Inc. Nrwd, USA. [4] Raim, M.K.A and Gardner, P. Te Design f Nine Elements Quasi Micrstrip Lg Peridic Antenna RF and Micrwave Cnference, Oct.4. [5] Hall, P.S., Multictave bandwidt Lg peridic Micrstrip Antenna Array IEE prc.vl.33pt H N..986.pp7-36. Vlume Issue December 4 Page 33