丌 n 1+s e k e 取左半平面极点 H()=H(s)H(-s) 给H(s) H(S) H(S B2(s) s-已 )(S-e4) B, (s) 对于n阶 s+V2S 参见P506表6-18 0 4 1 1 2, 1 ( ) s n H s + =  = =     4 7 4 5 4 3 4 1 , , , j j j j k S = e e e e ( ) ( ) ( ) 2 H s = H s H −s  4 1 j e  4 3 j e  4 5 j e  4 7 j e 取左半平面极点 给H(s) 2 1 1 ( )( ) 1 ( ) 1 ( ) 2 4 5 4 3 2 + + = − − = = s s s e s e B s H s j  j  ( ) 1 ( ) B s H s n = 对于n 阶 参见P506表6-1