If the blocked portion of the aperture is illuminated so the energy there is absorbed, then the total transmitted power P t in the expression (11.1.16) for gain is unchanged, while the area over which...If the blocked portion of the aperture is illuminated so the energy there is absorbed, then the total transmitted power P t in the expression (11.1.16) for gain is unchanged, while the area over which →E_′ff is integrated in (11.1.13) is reduced by the 1 percent blockage (100 2 is 1 percent of 1000 2 ).