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ri !0XstSourcero ¾Ç¼w¨c©xa!0yz#Â´ÁÔ ∆r¥-!0Îde¤v r ª θ ¤

¼ ∆r ª ∆θ +Q ∆l 6EI (r ,θ ) = (ri + ∆r / 2,0) ¾ + r riOÎdeXb ϕ  r ,θ ø 2 Ç¼!

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(r ,θ ) = (ri + {i − 1}∆r , { j − 1}∆θ ) ≡ (i, j ) i = 1,L, N , ro = ri + N∆r , j = 1,L, M , M∆θ = π ^ ¾ϕ Õ TE m£­ Er Eθ ª H ϕ ÆÂøA­ÆÂθïÛro 1. Yee ¤ÉßK

 Er (i, j )   Er (ri + {i − 1 2}∆r ,{ j − 1}∆θ )   Eθ (i, j )  =  Eθ (ri + {i − 1}∆r ,{ j − 1 2}∆θ )  H ϕ (i, j )  H ϕ (ri + {i − 1 2}∆r ,{ j − 1 2}∆θ )
 ÇfghÂ±ÁÆÂ∆θ

(1)`¦c1 H ϕ (i + 32 , j + 12 ) + c 2 H ϕ (i − 12 , j + 12 ) + c3 H ϕ (i + 12 , j + 32 ) + c 4 H ϕ (i + 12 , j − 12 )+ c0 H ϕ (i + 12 , j + 12 ) = b(1 − δ i , N ) R (i + 32 )(1 − δ 1,i ) R (i − 12 )c1 =c=,,2
ε r (i + 1, j + 12 ) R (i + 12 )ε r (i, j + 12 ) R (i + 12 )(1 − δ j , M ) S ( j + 32 ) ∆r 2
(1 − δ 1, j ) S ( j − 12 )∆r 2c3 =
c=,,422ε r (i + 12 , j + 1){R(i + 12 ) ∆θ } S ( j )ε r (i + 12 , j ){R(i + 12 )∆θ } S ( j )1 − δ 1,i  1 − δ i,Nc 0 = k 02 ∆r 2 − +11  ε r (i + 1, j + 2 ) ε r (i, j + 2 ) A1, jA j,MS ( j + 12 )∆r 2 ++2{R(i + 12 )∆θ }  ε r (i + 1, j + 12 ) ε r (i + 12 , j + 1) 4 I∆l∆rδ 1,i δ 1, jb =3
ε r (i + 12 ,1)π {R (i + 12 )∆θ }(2)k0 , δ m, n , R (i ) , ª S ( j ) X+{H> µ£n¤R (i ) = ri + (i − 1)∆r ,S ( j ) = sin{( j − 1)∆θ }­( j ≠ 1)
1 S ( j ),,A1, j = 1
4 S ( j + 2 ), ( j = 1)

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1= ∑ Dη exp(− Bη z )σ ( z ) η =1(4)B  Dη 12, η−1  = (46.9, 4.527 )η =1 , (22.2, 0.357 )η = 2 , (5.9, 0.121)η = 3
 10 Ωm km  60 km #é²#aÉyzßÉOÊÇb îωεr = 1−D2pe(5){ω − j (ν en + ν ei )}ω

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D,+{Xîé²ªE,+{EÙ IRI mn¤É³ýþ,+{ν en ªν ei ­
ν en = { 4.6 N N 2 Re0.95 + 4.3 N O 2 Re0.79 + 1.5 N O Re0.85 }× 10−15 m 3s −1
ν ei = ( 1.84 × 10− 6 s −1m 3K 3 2 ){16.33 + 0.5 ln (Te3 N e )} N eTe− 3 2
N N 2  N O 2 ª N O ¼(6) N2O2ª O Re  Te /(300K ) Te [K][­Xîé²Ù[ NRLMSISE-00 mn¤É³ýþÄ 2, 3  FDFD i¼ ,+{±Á¢

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ξ = [ξ1 ξ 2 L ξ Λ ] KT·¸,+{L{Î ÃÄÅÆÇÊ(È2Π(ξ ) = G • ξ − γ + αY (ξ )(9) Π(ξ ) ¡ö£ÉE?ÊÕ{ α ÆÇÊ Y (ξ ) ËOÊÊÕ{ Y (ξ ) = ξ ÉÌ«Î(9)ÊÕ{Íß 0 L Î2È­ \ÏÐÑÒÎÈ­∇Π(ξ ) = G T • (G • ξ − γ ) + αξ = 0(10)2.4. 
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CIP is`â CIP i$Îdey­ 25 dB #VW È*¦ö÷[4])wÛ6§+ôjCk£ôlEÔzCIP iºû TF/SF ÁÛOÛ,+·]¤¡¬{¶Âyz|Âð*¦ö÷ )xTF/SF Æ³Í c|*¦ö÷[6])[5]4. ⚿⺰  ELF 9A `ÂÃ½Oi (ð ÖÆ<¾v½O

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ROi Generalized Cross Validation cHx}RdôC£DE9AôjCk£ôlEû³±ÁPiConstrained Interpolation Profile (CIP)i}R (ðÖ:/<XÉ:/ÉÂÃ½OðST·¸DÉÏ­ðÉ ELF ±+z~}Û¦ö÷[2]³­
 0"ÝL·¸ÉROÂÃóÊX"­ÉÈLFð ÆûÂÇ01¦§[
_Õ/$|­ð0"¦§[n£ `_Õ /$ÓÔ⻢ㄉ Ö:/ ³Æ JFE21 À  §ෳ⠨ᢥ₂1.

A. P. Nickolaenko and M. Hayakawa, Resonances in the Earth-Ionosphere Cavity, Kluwer,Norwell, MA, 2002.

⎇ⓥഥᚑᦼ㑆ਛߩ⊒⴫ᢥ₂[1] Ë, Æ, “]^ü¸ ` ELF ±Á·¸n£­ôC£DE9A
B|i,” é²²:/, No.68, pp.17-18, 2006.
[2] Y. Ando and M. Hayakawa, “Recent studies on Schumann resonance,” IEEJ Trans. FM, vol.126,no.1, pp.28-30, 2006.
[3] Y. Ando and M. Hayakawa, “Use of generalized cross validation for identification of global
lightning distribution by using Schumann resonances,” Radio Science, vol. 42, no. 2, RS2S16,
doi:10.1029/2006RS003481, 2007.
[4] Y. Ando and M. Hayakawa, “Implementation of the perfect matched layer to the CIP method,”
IEICE Trans. Electron., vol.E89-C, no.5, pp.645-648, 2006.
[5] Y. Ando and M. Hayakawa, “Total-Field/Scattered-Field boundary condition for CIP method,”
PIERS2006, Tokyo, Aug. 2006.
[6] Ë, Æ, “2  M ë CIP i{¶ÂÕ}R,” 2007 }âãÑùé (2007 } 3 <¦üO).

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