A new 2-18 GHz quad-ridged horn antenna

A novel design of a dual-polarized broadband 2-18 GHz horn antenna with VSWR <= 2.2 is presented. The designed horn antenna is most suitable as a feed element in reflectors of the radar systems and EMC applications. A coaxial line to quadruple-ridged waveguide transition with a new conical cavity back and a technique for tapering the flared section of the horn is introduced to improve the return loss and matching of the impedance, respectively. In order to overcome the deterioration of the broadside radiation pattern at higher frequencies, common to broad band ridged horn antennas, a new modified horn antenna with arc shaped aperture is introduced. Results of simulation obtained via two different software packages, HFSS and CST, for VSWR, isolation, radiation patterns, and gain of the designed quad ridged horn antenna as well as the modified horn antenna are presented and discussed.