■(b)种情况,串联环节间有同步采样开关, 1(s)=G1(S)r(s),Y(s)=G2(S)(s) r1(s)=[G1(s)(s)]=Gi1(s)r(S Y(s)=[G2(s)(s)]=G2(s)1(S G1(s)/G2(s)r(s) G(z) Y(2)Z[Y(s) G1(z)G2( 7(z)Z[r(s) (b)种情况，串联环节间有同步采样开关，  则 ( ) ( ) ( ), ( ) ( ) ( ) * 2 1 * 1 1 r s = G s r s Y s = G s r s ( ) ( ) ( ) ( ) [ ( ) ( )] ( ) ( ) ( ) [ ( ) ( )] ( ) ( ) * * 2 * 1 * 1 * 2 * * 2 1 * * * 1 * * 1 * 1 G s G s r s Y s G s r s G s r s r s G s r s G s r s = = = = = ( ) ( ) [ ( )] [ ( )] ( ) ( ) ( ) * 1 2 * G z G z Z r s Z Y s r z Y z G z = = =