Design optimization of reflectarrays
TICRA is working with the Technical University of Denmark (DTU) on an ESA-ESTEC contract to develop an efficient and accurate modeling tool for printed reflectarrays. With the enhanced analysis tool and TICRA’s expertise in reflector and horn optimization, efficient synthesis strategies for advanced printed reflectarrays are developed. Sources of error in reflectarray analysis and how to overcome these issues to improve the analysis accuracy have been investigated. To this end, several benchmark reflectarrays that exaggerate some of the sources of error were designed, manufactured and measured at the DTU-ESA Spherical Near-Field Antenna Test Facility.
The results of this ESA-ESTEC study will eventually be fully incorporated into TICRA’s software packages, which greatly enhance the possible modeling scenarios. Typical examples include combinations of solid reflectors and reflectarrays, design and optimization of contoured beam reflectarrays, high-level feed models or import of a measured feed field, as well as accurate evaluation of undesired effects such as strut scattering etc.
An example is shown below where a contoured beam reflectarray has been synthesized using the code developed during the study. The reflectarray is optimised to radiate a high-gain beam within the European coverage with sidelobe suppression on the Southern African contour. The reflectarray was measured at the DTU-ESA Spherical Near-Field Antenna Test Facility and the agreement between simulations and measurements is very good.