Comparative study of space-mapping-based optimization techniques for microwave design

Space mapping (SM) has been used in microwave engineering for over a decade and demonstrated as one of the most efficient simulation-driven design techniques available to date. By exploiting a fast and physically-based surrogate model, SM allows rapid optimization of an EM-simulated structure of interest (fine model). Several variations of SM algorithms have been proposed including recently introduced tuning space mapping (TSM) that can be even more efficient. However, TSM requires modification to the optimized structure (i.e., “cutting” and inserting of the tuning ports). Here, for the first time, a comparative study of various SM and TSM algorithms is carried out. Advantages and disadvantages of these techniques are discussed and illustrated through design examples. Recommendations for users of SM/TSM are given.