South Tehran Branch, Islamic Azad University
controlling and suppressing sidelobe level of a symmetric parabolic antenna is presented. This sidelobe suppression is done by adding three disc-shaped elements on the surface of the parabolic antenna. By adjusting the position and height of these elements, the surface of the side lobe is changed. With this method, the antenna is designed in the X-Band so that the output of the radiation pattern is such that the level of the first side lobe is relatively lower than the other side lobe. Also, the VSWR for the antenna is designed across the frequency range below 1.82. The simulations show that the level of the first side lobe on the right side of the antenna radiation pattern is reduced by 18dB compared with the simple reflex antenna with similar dimensions and specifications, and the VSWR in the frequency range (11.5GHz-12.5GHz) between 1.1 <VSWR <1.82 .