Inverse Design of Multi-Input Multi-Output 2-D Metastructured Devices

In this work, an optimization-based inverse-design method is provided for multi-input–multioutput (MIMO) metastructured devices. Typically, optimization-based methods use a full-wave solver in conjunction with an optimization routine to design devices. Due to the computational cost, this approach is not practical for designing electrically large aperiodic metastructured devices. To address this issue, a 2-D circuit network solver using reduced-order models of the metastructure’s unit cells is introduced. The circuit network solver is used in conjunction with a gradient-based optimization routine that uses the adjoint variable method to solve large-scale optimization problems such as those posed by metastructured devices. To validate the inverse-design method, a planar beamformer and an analog signal processor for aperture field reconstruction are designed and validated with full-wave simulations.