Development of Simulation Program on Electromagnetic Wave Propagation

Transcription

1 Developmen of Smulaon Pogam on lecomagnec Wave Popagaon Wanee Weeasn and Somsak Akamagool Kng Mongku s Unves of Tecnolog No Bangkok, Facul of Tecncal ducaon, Depamen of Teace Tanng n leccal ngneeng, Bangkok, Taland Absac- Te eseac poposed e developmen of smulaon pogam on elecomagnec wave popagaon o be used as an nsuconal meda n elecomagnec wave couse. Te developed smulaon pogam s based on e GUI funcon of MATLAB pogam conssng of GUI-npu paamee wndow, calculang menu, and gapcal dspla wndow. Te pefomance of developed smulaon pogam evaluaed b 5 epes was moe appopaed level ( X = 4.0, S.D.=0.0). Afe mplemenng e developed smulaon pogam b usng a samplng goup fom Rajamangala Unves of Tecnolog Pa-Nakon, Facul of Indusal ducaon, e sudens sasfacon was a g level ( X = 4.4, S.D.=0.4). As esuls, e developed smulaon pogam can be used appopael n e eacng of elecomagnec wave couse. Moeove, also elps e leane o ave moe knowledge and sklls conssen o epeced leanng oucome of engneeng cuculum. Kewods- GUI-MATLAB, Smulaon pogam, Wave popagaon. I. INTRODUCTION Nowada, undegaduae as suded connuousl n elecomagnec engneeng couse because of s a fundamenal subjec a s mpoan and necessa fo engneeng educaon. In e eacng of elecommuncaon engneeng, moden ecnolog wll focus on e g fequenc ccu desgn, weless communcaon and ec. Tus sudens sould ave e basc knowledge n elecomagnec felds and wave as well. Howove, n e suveng e poblem ssues, we found a feedback nfomaon fom eaces and sudens was pesened and suggesed as follows: ) e mos elecomagnec equaons n veco fom ave complcaon a povde sudens o dsegad n leanng. Moeove, sudens mus ave gl magnaon o undesandng e eo and eall pncple of elecomagnec wave, ) e mos eacng meods ae lecue and eecse es us sudens ae bong and naenve n leanng and eacng, 3) e nsuconal meda s unsuppoed and nappopae n eacng, don dvesfed and don ave adequae n a classoom [], []. Pesenl, vaous elecomagnec smulaos ae appled n e eacng of engneeng suc as Sonne, CST, I3D and ec. Mos smulaon ae used n eseac and developmen o ceae moden nnovaon [3] bu don suppo o leanng and eacng n classoom as effcenl. Tus, seveal eseaces ave be developed e elecomagnec smulaos [], [] based on Malab sofwae, C ++ pogamg, and ec. In s pape, e developmen of smulaon pogam on elecomagnec wave popagaon engneeng educaon was peposed based on GUI funcon of MATLAB. Te developed smulaon pogam can calculae and llusae e elecomagnec wave popagaon, polaaon and waveguded wave dsbuon. In ode o deeed leanng acves usng e elecomagnec smulao, leanes wll be able o ave g leanng acevemen. II. THORY lecomagnec waves ae fomed wen an elecc feld couples w a magnec feld. Te magnec and elecc felds of an elecomagnec wave ae pependcula o eac oe and o e decon of e wave. A. Polaaon Consdeng e sweep b e me of e elecc feld eco of e wave a an poson, e elecc feld equaon n e decon of and wll popagae n e decon and wen n e fom of e elecc feld equaon n ems of e me doman equaon [4], + + v - - v = cos( w- b+ q ) a + cos( w + b+ q ) a. o o Smlal, e equaon of e magnec feld n e em of e me doman s as follows, + - H o o cos( + ) a v w b q cos( w ) b - q a v = Wen defnng e angula dffeence beween e elecc feld n e and decon, we ave q = q = q and en we e elaonsp equaon as follows, v v = ( a + a )cos( w - b + q). (3) o o Te angle of ansmsson n e Tl angle beween e elecc feld and e -as s as follows, - o = an. (4) o ICTecd5(-)P006, Bangkok, Taland 434 DOI:0.446/c.fe

2 X Medum I Medum II,,,,, H Fgue. Lnea Polaaon Lnea polaaon can be consdeed wen e dffeen angle beween wo decons of elecc feld s eo, as sown n Fgue, fo e oonal polaaon f e -feld angle s 0 and vecal polaaon f e - feld angle s 90. Ccula polaaon wll povde a = = o o o and e pase angle s f - f = ± 90 o, as sown n Fgue. Te elecc feld wave equaon s as follows, v v ( cos( w b ) sn( w b ) ) = - a m - a. (5) o Fgue. Ccula polaaon Consdeng e value of e pase beween e elecc feld n e and decons, f f - f = 90 o wc saed a Rg -and polaaon and f f - f = 90 wc saed a Lef-and polaaon, as sown n Fgue 3. Fgue 3. Roaon g-and polaaon and lef-and polaaon Consdeng e llpcal polaaon, can be deeded a e wave amplude of ¹ and o o e pase angle s dffeen of f - f = f, as sown n Fgue 4. Te elecc feld wave equaons ae as follows, æ ö æ ö cos( q) D - + = sn ( Dq) (6) o è ç ø o o çè o ø Fgue 4. llpcal polaaon o, H Z=0, H Fgue 5. Plane wave popagaon n dffeen medums B. Plan wave and popagaon Consdeng e ncden wave of an elecc feld ( ) and magnec feld (H ) n bounda aea beween lossless medum I ( s = 0) and pefec conduco of medum II ( s = ), as sown n Fgue 5, e efleced wave n decon - of medum I, and ansmed wave n decon + of medum II wll occupaon. Te lossless delecc medum can be consdeed a e conducv s = s = 0, wen consdeng e ncden wave n decon + n e medum I a poson of plan =0, e elaon equaons of elecc feld and magnec feld ae as follows, - jb v = e a (7) - jb v H = e a Because of e dsconnuous condon occued a = 0, e ncden waves ae dvded no efleced waves popagang no medum I and a pa of e wave wll ansm oug n e medum II. Te efleced wave Z (8) equaon(,h ) a poson = 0 s wen as follows, + jb v = e a, (9) H = v + jb ( ) v - a = - e a, (0) and e ansmed wave equaon (,H ) a poson = 0 s wen as follows, - jb v = e a, v - jb ( ) ( ) v H = a = e a. Wen b s e pase consan n medum II and s e nnsc mpedance of medum II. Reflecon coeffcen ( G ) and ansmsson coeffcen ( T ) n ems of e nnsc mpedance of medum I and II ae as follows, - G= =, (3) + and T = =. (4) + ICTecd5(-)P006, Bangkok, Taland DOI:0.446/c.fe

3 Te equaon elaons of Gand T ae as follows, +G= T (5) C. Waveguded wave dsbuon In e deal wavegude, e sucual wall s a complee eleccal conduco and n e wavegude s fee space, e coss secon s a ecangle conssng of sdes a and b wc ae e dmensons along e and aes n e especve coodnaes. Te leng of e wavegude conduco s e same as e decon [5]. Te waveguded wave dsbuon consss of modes as TM mode (Tavese Magnec Feld) and T mode (Tavese lecc Feld), e elaon equaons of wave n wavegude ae as follows, ) Te elaonsp equaon of TM modes n ecangula wavegude s 0, H =0. Te wave equaon s as follows, kc (6) Te wave componens n e ecangula wavegude n mode TM ae wen n equaon followng. m n Asn ( )sn( ) (7) a b k m n j Asn ( )sn( ) (8) c k m n j Asn ( )cos( ) c (9) k m n H j Asn( )cos( ) (0) c k m n H j Acos( )sn( ) kc a b H 0 Te waveleng of e wave of TM can pesen as follows, kc m n c a b (3) ) Te elaonsp equaon of T modes n ecangula wavegude s =0, H 0. Te wave equaon s as follows, H H H kch (4) Te wave componens n e ecangula wavegude n modet ae wen n equaon followng. H Bcos k cos k (5) k m n j Bsn ( ) cos( ) (6) c k m n H j Acos( )sn( ) (7) c k m n j Bsn ( ) cos( ) (8) c k m n H j Bsn ( )cos( ) (9) c 0 (30) III. RSARCH MTHODOLOGY Te pocess of desgnng GUI smulaon pogam on elecomagnec wave popagaon s appled o e elecomagnec engneeng educaon o elaed felds. Te MATLAB based smulaon pogam consss of 3 pas: ) nal paamee wndow, ) calculang menus and 3) dspla wndow. Te developed smulaon pogam based on e gapcal use neface GUI funcon of MATLAB sofwae llusaed n Fgue 6. Sa Inal value Desgn Paamee Calculang Dspla d nd YS NO Fgue 6. Smulaon Dagam Fgue 7. ample of developed smulaon pogam IV. IMPLMNTATION AND RSULTS Te mplemenaon w smple goup can been sown n Fgue 8. Te eseac as been pesened n 3 secons ncludng ) e developed smulaon pogam ) e qual evaluaon of smulaon pogam 3) e suden s sasfacon. And 4) e effcenc of smulaon ICTecd5(-)P006, Bangkok, Taland 3 DOI:0.446/c.fe

4 pogam. Te esuls of smulaon pogam can be epesened n Fgue 9-0. Fgue 8. Implemenaon n classoom A. Te evaluang qual of smulaon pogam. Te developed GUI funcon of MATLAB based smulaon pogam n e eacng of elecomagnec wave popagaon was evaluaed b 5 epes wo ave epeence n e eacng of elecommuncaon engneeng o elaed. Te fndngs ave a moe appopae ( X =4.0,S.D.=0.0), as sown n Table I. Fgue 9. Resuls of wave popagaon smulaon Fgue 0. Resuls of T/TM Mode smulaon TABL I Te esuls of e qual of smulaon pogam (N=5) Appopae Level valuaed opcs X S.D. Inepe. Appopaon of smulaon pogam g. Accuaon of smulaon pogam g 3. as o use g 4. Appopaon of conen and desgn 5. ncouage suden o undesand g couse conen g Toal g TABL II Te sudens sasfacon of smulaon pogam (N=9) valuaed opcs Appopae Level X S.D. Inepe. Appopaon of developed smulaon. Accuaon of smulaed esuls 3. as o use g g g 4. Appopae fo conen and pupose g 5. ncouage suden o lean and aend g Toal g B. Te sudens sasfacon Te developed GUI funcon of MATLAB based smulaon pogam was mplemened b 9 sudens wo egseed n e elecomagnec wave couse n academc ea /07 a Rajamangala Unves of Tecnolog Pa-Nakon. Te sample goup was aug b usng e developed smulaon pogam. Afe leanng all lessons, e sudens' sasfacon was evaluaed usng e quesonnae fom e fndngs afe eacng usng e developed smulaon pogam was found a e sudens sasfacon was a g level ( X =4.4,S.D.=0.4), as sown n Table II. C. Te evaluaed esuls of effcenc of e smulaon pogam. In e ng ou usng 9 samplng sudens, sudens done e pees befoe leanng. In e eacng and leanng of elecomagnec wave couse n eac lesson, eace wll povde e couse conens, e leanng acves, and measung and evaluang e leanng acevemen especvel. Te daa gaeng was analed fo effcen valdaon b Megugans's eo [6], as sown n Table III. We found a pefomace of developed smulaon pogam was valdaed w e o Megugans s eo equle o.7 accodng o Megugans's fomula (moe an.0). Tes Pees Poses TABL III Te effcenc of smulaon pogam (N=9) Full Mnmum Mamum Mean Megugans s scoe scoe scoe value eo (pon) V. CONCLUSION.7 Te developmen of MATLAB based smulaon pogam of elecomagnec wave popagaon as been pesened fo leanng and eacng of elecomagnec engneeng couse. Te developed smulaon pogam s able o use n calculaon and pesenaon of elecomagnec wave penomenon suc as, wave popagaon, polaaon and waveguded wave dsbuon. Becuase of e pofomance of e developed ICTecd5(-)P006, Bangkok, Taland 4 DOI:0.446/c.fe

5 smulaon was conssen o e sandad cea of Megugans s fomula and e sudens sasfacon usng e developed smulaon pogam was also a a g level, e developed smulaon pogam can be used as an nsuconal meda o encouage sudens o ave moe vaous knowledge sklls. VI. RFRNCS [] A.Pomee, P.Nngpom, S.Coocadee and S.Akamagool Smulaon Sofwae fo lecomagnec Wave Popagaon n Conducng Cav Usng Meod of Momens n Te Jounal of KMUTNB., Vol. 4, No., Ma.- Aug. 04, pp [] Jncao.Du, Wegen Cen a all. Smulaon analss on e popagaon caacescs of elecomagnec wave geneaed b paal dscages n e powe ansfome n I Confeence on leccal Insulaon and Delecc Penomena, pp 79-8,06. [3] G.Wenseng, D.Dengwe a all. Popagaon Popees of Hg- Fequenc lecomagnec Wave Toug Tpcal In-Feld GIS Sucues n I Tansacons On Powe Delve, Vol. 9, No. 6, Decembe, pp , 04. [4] Xu.D, Kuang.Z, a all Measuface fo polaaon and pase manpulaon of e elecomagnec wave smulaneousl n Inenaonal Confeence on lecomagnecs n Advanced Applcaons, pp , 06. [5] Kaena Nesv, Scaeng and Popagaon of e T/TM Waves on Pe-Facal Impedance Gang n Numecal Resuls, n Te 8 uopean Confeence on Anenna and Popagaon, pp , 04. [6] P.Jaan and T.Snnakul Te Developmen of Web-based Insucon on Offcal Lees n Wod Pocessng Applcaon Subjec usng Demonsaon Tecnque, n Te 5 Rajamangala Unves of Tecnolog Naonal Confeence, 0. ICTecd5(-)P006, Bangkok, Taland 5 DOI:0.446/c.fe