Tuning space mapping design framework exploiting reduced electromagnetic models

Tuning space mapping (TSM) with embedded tuning elements is a recent development in space mapping technology. The process allows efficient design optimisation of microwave components by substituting sections in an electromagnetic model with corresponding sections of designable equivalent elements. Available parameters of these elements are subsequently tuned and their optimal values are `translated` into relevant changes in the original structure`s design variables. Although the TSM optimisation process typically requires only a few iterations to complete, the simulation of the structure with a number of co-calibrated ports (required for subsequent insertion of the tuning elements) can be substantially longer than that of the original structure. This results in substantial computational overhead of the design process. Here, the authors review a fast TSM algorithm that exploits a reduced structure with significantly fewer co-calibrated ports for creating the tuning model and allows us to obtain dramatic reduction of the computational cost of the optimisation process. In a design framework, the fast TSM as well as other TSM methods are implemented and automated in space mapping framework (SMF) software. Comprehensive verification and comparison with the standard TSM are provided through several examples of microstrip filters.