Plane-Wave Generation through General Near-Field In-Band Reflectarray Direct Layout Optimization with Figure of Merit Constraints in mm-Wave Band

A general near-field (NF) in-band synthesis strategy is presented for the direct layout optimization (DLO) of reflectarrays with application to generation plane waves mm-wave band. The technique relies on definition relevant figures merit (FoM) and use a gradient-based minimization algorithm. To this end, volume where NF computed divided into number disjoint regions FoM are defined. These define performance antenna their enables improvement compared previous approaches described in literature, while reducing memory footprint algorithm accelerating computation. procedure several stages facilitate convergence towards successful outcome. First, phase-only carried out at single frequency. Then, reflectarray obtained using method moments based local periodicity, accounting mutual coupling between elements. Finally, an DLO performed frequencies directly optimizing FoM. results show that complies requirements frequency range 27 GHz–29 GHz within 5G new radio n257