In this work, the influences of amplitude tapering and feed aperture blocking in gain and first sidelobe level of Ku-band parabolic reflector antennas are investigated. Two different parabolic antenna configuration groups are proposed to determine each of these degradation factors. Designed parabolic reflectors are fed by pyramidal and conic horns to observe the blockage effect of feed type on Ku-band satellite reception applications. In the first examination to designate the influence of illumination loss due to amplitude tapering four parabolic reflectors are designed with 8 dB, 10 dB, 15 dB and 20 dB edge taper values on reflector apertures. Thereafter, thanks to the reflectors designed with the same edge taper value, but having different diameters, it became possible to observe, purely the influence of feed blockage on the radiation characteristics. Both theoretical and simulated patterns of reflector systems are presented.