A spherical to plane wave transformation using a reflectarray

A reflectarray has generally been used as a replacement for a reflector antenna. Used in this capacity, different configurations (prime focus, offset etc.) and various applications (dual frequency, scanning etc.) have been previously demonstrated with great success. Another potential application that has not been explored previously is the use of reflectarrays to compensate for phase errors in space power combining applications such as space-fed lens and power combining amplifier. In these applications, it is required to convert a spherical wave to a plane wave with proper phase correction added to each element of the reflectarray. This paper reports an experiment to investigate the feasibility of using a reflectarray as an alternative to a lens in space power combining. The experiment involves transforming a spherical wave from a orthomode horn to a plane wave at the horn aperture. The reflectarray consists of square patches terminated in open stubs to provide necessary phase compensation. In this paper, preliminary results will be presented and the feasibility of such a compensation scheme will be discussed.