Reflection phase error analysis of microstrip reflectarrays

The radiation characteristics of a reflectarray antenna with element type combination is analyzed using reflection phase errors. The reflectarray is designed with the combination of three element types: square patch (SP), square ring (SR), and ring-loaded patch (RLP). The reflection phase error of the reflectarray is compared with those of two reflectarrays using single element types (SP and RLP, respectively). Compared to the reflectarrays with only SP elements or RLP elements, it is shown that the reflection phase errors are reduced with the combination of the element types at the target frequency, and thus improved radiation performances are achieved.