Solving design and inverse-imaging problems through electromagnetic simulation

Numerical electromagnetic analysis has been rapidly developing for more than three decades now, matching closely the remarkable progress of computing technology. Commercial packages for high-frequency computer-aided analysis are nowadays standard toolboxes in industrial and academic microwave laboratories. Yet designers and researchers rarely use full-wave simulations in the early to intermediate stages of the design process. The usual practice is to use them only as a final verification tool before prototyping. This is not for the lack of suitable optimization algorithms as these have grown to no lesser degree of sophistication and commercialization than electromagnetic solvers. The weakest link in electromagnetic computer-aided design is that between the simulation and the optimization algorithms. In this talk, we review the latest developments in simulation-based optimization in microwave engineering. We outline the requirements of optimization algorithms in design and inverse problems, and we discuss how electromagnetic simulators must improve to meet these demands. We illustrate the importance of these developments through design and microwave-imaging examples.