8.1.2 Errors of non-unity and unity feedback 只 E G Non-unity feedback sys HECH E=R-HC =H(,R-C) H HE R=RIGE E E |1 C GH Unity feedback system8.1.2 Errors of non-unity and unity feedback R Ea C HC =C' G H R C H 1 GH ' 1 R R H = E' Non-unity feedback sys. Unity feedback system Ea = R − HC ) 1 ( R C H = H − = HE' Ea H E 1  ' =