Abstract: A modular antenna has a primary radiating aperture which can either be an array of radiating elements or a passive reflector. In regards to the array of radiating elements, a feed network interfaces with the radiating elements to form the modular antenna array. The feed network has a number of output ports wherein each output port of the feed network is adapted to interface with each feed port of the radiating elements. The feed network can be placed at various locations along the antenna array to change to radiation characteristics of the antenna array. When passive reflector is used, a modular feed interfaces with the waveguide. The feed module controls the sector radiation pattern. The vertical reflector surface controls the elevation radiation pattern. The feed module can consist either of an antenna array or a single element utilizing beam shaping.