Optimal Inverse Design Based on Memetic Algorithms -- Part 2: Examples and Properties
Optimal inverse design, including topology optimization and evaluation of fundamental bounds on performance, which was introduced in Part~1, is applied to various antenna design problems. A memetic scheme for topology optimization combines local and global techniques to accelerate convergence and maintain robustness. Method-of-moments matrices are used to evaluate objective functions and allow to determine fundamental bounds on performance. By applying the Shermann-Morrison-Woodbury identity, the repetitively performed structural update is inversion-free yet full-wave. The technique can easily be combined with additional features often required in practice, \eg{}, only a part of the structure is controllable, or evaluation of an objective function is required in a subdomain only. The memetic framework supports multi-frequency and multi-port optimization and offers many other advantages, such as an actual shape being known at every moment of the optimization. The performance of the method is assessed, including its convergence and computational cost.