Tripling bandwidth of hat feed by genetic algorithm optimization

Genetic algorithm optimization combined with V2D-FDTD simulations has been used to redesign the geometry of the Hat Feed. The new evolved feed has improved return loss properties while keeping the good overall efficiency of the original feed. The bandwidth of the new feed is about 33% (at 7.9 GHz), compared to about 11% for the original. In addition, the return loss level within the hand has dropped about 8 dB on average - it is better than 17.7 dB over the entire band and better than 20 dB in almost 90% of the hand. The new feed has been manufactured and return loss measurements confirm the simulated results.