■(a)种情况,串联环节间无同步采样开关, Y(S=G(SG,(S)r(S) 则 G(c)=(=)=4(s) R(=)Z[r(s)] Z[G1(s)G2(s)*Z[() ∠[r(s) G1G2(=)≠G1(=)G2(=) (a)种情况，串联环节间无同步采样开关，  则 * * 1 2 * Y (s) =[G (s) G (s)r (s)] ( ) ( ) ( ) [ ( )] [ ( ) ( )]* [ ( )] [ ( )] [ ( )] ( ) ( ) ( ) 1 2 1 2 * * 1 2 * * G G z G z G z Z r s Z G s G s Z r s Z r s Z Y s R z Y z G z =  = = =