Design of a Broadband Cosecant Squared Pattern Reflector Antenna Using IWO Algorithm

A cosecant squared pattern reflector antenna fed by a pyramidal double-ridged horn for 2-18 GHz is presented. Invasive weed optimization (IWO) algorithm is used for synthesizing the point source doubly curved reflector antenna. IWO method makes antenna synthesis flexible to achieve extra desired features such as low side lobe level (SLL) and low ripples in the shaped beam region. The simulation results via FEKO software package further prove the validity and versatility of this technique for solving reflector synthesis problems. In addition, experimental investigations are conducted to understand the complete reflector antenna system behaviors. Good agreement between the simulation and measurement has been achieved. The ripple in the cosecant squared region and the SLL is less than 1.5 dB and 25 dB, respectively. Based on the obtained results, the proposed reflector antenna can be used in broadband surveillance-search radar systems.