Fast solution of inverse problems in the RF domain using topological sensitivity and hybrid-ON/OFF method

Topological sensitivity (TS) formulation is derived, for the first time in RF domain, and applied to the hybrid-ON/OFF method for the fast solution of inverse problems. The formulation is based on continuum approach and adjoint variable method. The TS is directly calculated from volume field solutions, and used to determine the ON/OFF status of the unit cell. The proposed method is applied to dielectric material reconstruction, and the results show the validity and effectiveness of the proposed method.