GUC (Dr. Hany Hammad) 11/2/2016

Transcription

1 GUC (D. Han Hammad) //6 ctu # 7 Magntic Vct Ptntial. Radiatin fm an lmnta Dipl. Dictivit. Radiatin Rsistanc. Th ng Dipl Th half wavlngth Dipl Dictivit. Radiatin Rsistanc. Tavling wav antnna. Th lp antnna. Antnna Fild Zns Kaus & Mahfka, Antnnas 3 d d., McGaw Hill COMM (7) ctu #5

2 GUC (D. Han Hammad) //6 Magntic Vct Ptntial Idl dh 4R Jdv aˆ H 4πR R lctic Cunt Suc J Intgatin Path Radiatd Filds Intgatin Path Magntic Vct Ptntials A Diffntiatin Path Magntic Vct Ptntial Mawll s quatins B jb jh t D H J H J j t D v F f spac n vlum chag dnsit D B s Nt: th divgnc f a cul f an vct is A is th magntic vct ptntial B A jb j A ja ja In lctstatics V ja ja V A V ja V t COMM (7) ctu #5

3 GUC (D. Han Hammad) //6 Magntic Vct Ptntial H J j H H B J j A J j J j V ja k A A J jv A A jv J A k A A jv J A k A A k A J A jv nt s cnditin A jv Th divgnc and th cul a indpndnt, w dfind th cul f A w hav th fdm t dfin th divgnc. A k A J Magntic Vct Ptntial Givn J Slv f A A k A J H A A A ja j A In gnal A A aˆ A aˆ A aˆ J J aˆ J aˆ J aˆ COMM (7) ctu #5 3

4 GUC (D. Han Hammad) //6 Radiatin fm an lmnta Dipl A k A J A k A J Assum w hav J Th cunt is a pint suc (smmtical) thn it is nt functin f. A k A J A A k A J J J aˆ A A k A J A A k A J Slutin A J 4 jk dv Slutin f Inhmgnus vct ptntial wav qn. Assum hmgnus d A d jk jk Slutin A C A C Ppagatin is in + jk A A C C Assum static cnditins thn k A J A c A ampl In lctstatics Similal J A J A dv V 4 v Slutin jk J V dv A dv Final Slutin fm bth 4 v 4 v da d k A COMM (7) ctu #5 4

5 GUC (D. Han Hammad) //6 Radiatin fm an lmnta Dipl A cs A cs cs A A A H A H J dv A jki 4 J dsdl aˆ θ A cs cs A cs A A A A cs aˆ θ θ A θ J ds θaˆ jk dl I jk H H I A 4 A jk A A â â A A â Radiatin fm an lmnta Dipl H j H j I cs jk jk jki jk 4 jk jk F fa filds jki 4 k jk H jki 4 jk F F spac H 377 COMM (7) ctu #5 5

6 GUC (D. Han Hammad) //6 Antnnas Radiatin fm an lmnta Dipl. Dictivit. Radiatin Rsistanc. Th ng Dipl Th half wavlngth Dipl Dictivit. Radiatin Rsistanc. Tavling wav antnna. Th lp antnna. lmnta Dipl (Radiatin Rsistanc) P R H * av Avag Pnting vct ki Pav aˆ Wav 4 Pav ds ds W av ki 3 ki 4 dd dd ˆ a I k W av Als W I Wh av R ad k Nt: It is indpndnt f, whil th filds dca pnntiall with, th pw is cnstant. R ad 8 COMM (7) ctu #5 6

7 GUC (D. Han Hammad) //6 lmnta Dipl (Dictivit & Pattn) Pw Pattn D D. 5 4 dd 3 Maimum 9, 7 Nulls, 8 Dipl Dughnut Shap lctic & Magntic filds f lctic Cunt (J) (,, ) R (,, ) A 4 A 4 V V J jk J R jkr dv dv COMM (7) ctu #5 7

8 GUC (D. Han Hammad) //6 Th ng Dipl H jki 4 jki 4 R jk jk Th phas tm Th amplitud tm Cunt Suc I I I I k k d dh jkid 4R jkid 4R jkr jkr R cs R f f Cunt Distibutin R lmnta dipl Th ng Dipl d jk 4 / jk I / jk cs d jki 4 jk / / jk cs k d k jk cs d / / jk cs jk cs k d k ( d) k / jk cs d jki 4 jki 4 jk jk / / / jk cs k d k jk cs jk cs k d jk cs d COMM (7) ctu #5 8

9 GUC (D. Han Hammad) //6 Th ng Dipl jki jk / acs b ( a b) ( a b) k csk cs d jki jki 4 jki 4 jk jk jk / / cs k csk cs d / k cs d k cs k k cs cs / cs d / k cs k cs Th ng Dipl jki 4 jk cs k cs csk k cs cs ji jk csk cs cs k 4 cs cs k cs csk k cs ji 4 cs k cs csk cs jk H ji ji jk jk cs cs k cs csk k cs csk cs COMM (7) ctu #5 9

10 GUC (D. Han Hammad) //6 Th half wavlngth Dipl If ji jk cs Maimum Nulls cs cs cs / cs / cs ji jk kcs / csk/ cs / cs / cs cs k k cs 9, 7 cs (k ) Pattn fact / cs k k cs, 8 Th half wavlngth Dipl (Radiatin sistanc) W av k cs csk 5I cs Pav. ds dd k cs csk cs 3I d I R ad R ad Slvd numicall F =/ cs cs Int d R cs k cs cs( k ) 6 d Int R 8 cs cs 6 d i cs cs i i 8 COMM (7) ctu #5

11 GUC (D. Han Hammad) //6 Th half wavlngth Dipl i ( i ) cs( i ) cs (/cs( i )) cs (/cs( i ))/( i ) Th half wavlngth Dipl (Dictivit) D 4 cs 7 cs 4 8 dd.64 COMM (7) ctu #5