o(r, t) r.t Ir-r aA(r,t)=ATV dI′ 4π60广/F-r "exp[jol dv J()x|Jo4/-, dE 4πEo"V r 4"v () [)e E(r)=-Vw(rn)-84G)E()=Vr)-j04) B B(r)=V×A() XAU 0(r,t F,t)+E00 =0→V·A()+E0oj0(r 0 at p=-800at aAV(·A oou( ) ( ) ( ) t V V ' V a ' ' t ' V a ' ' ,t ,t     j 0 0 e exp j d 4π d 4π A r r r r r J r r r r r J r A r = −                  − − = −          − − =   ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( )  ( ) ( )   =  = − −       =    = − − B r A r E r r A r B r A r E r  r A r  j ,t ,t ,t t ,t ,t ( ) ( ) 0 0 = 0   ( )+ 0 0 j ( ) = 0    + A r r r A r       t ,t ,t ( ) ( ) (r) r r r r r r r r r r r        t V V e ' V a ' ' t V a ' ' ,t ' ,t j 0 0 exp j d 4π 1 d 1 4π 1 = −                  − − =          − − − =   ( ) 0 0 0 0 j      A   A =    = − t