3-D Microwave Field Synthesis via Projected Spatial Fourier Transform

In this letter, an analytical method based on projected spatial Fourier transform is presented to flexibly synthesize the 3-D spatially-shaped microwave fields. Distinct from the existing 3-D synthesis methods based on optimal algorithms, the proposed method can analytically calculate all element excitations of the antenna array, which allows real-time synthesis of the desired 3-D microwave field. Via this method, 3-D microwave fields with various intensity distributions can be flexibly synthesized, such as multi-target focused fields and uniform fields with specific shapes, which have been widely applied for wireless power transfer. Full-wave simulations demonstrate the validity of the proposed method. Both the multi-target focused field and the cuboid-shaped uniform field are successfully synthesized.