Matching of Waveguide Slot Antenna by Evolutionary Method

The impedance-matching is needed to improve the transmission efficiency of a waveguide slot array antenna with the small spherical dielectric lens. This paper reports the design method of the tuning screw for the impedance-matching by using the computational approach which consists of the FDTD method and the evolutionary method. From the optimized results, the VSWR in the frequency range from 11.8 to 12.2 GHz is decreased to less than 1.18.