Advanced RF Reflective Metal Mesh for High Frequency Deployable Reflector Antennas

Microwave Earth Observation instruments such as radiometers, SAR, altimeters and atmospheric radars are more and more required to combine a large RF radiating aperture and a high frequency operation, typically up to Ka-band. The large deployable reflector antenna (LDRA) is an excellent solution to meet this combined requirement because it is lightweight and low loss. Furthermore, it exhibits a high packing ratio and can be deployed once in orbit. The LDRA comprises several elements among which the RF reflective metal mesh, as part of the reflector RF surface, is considered as a key element. Indeed, the electrical, mechanical, thermo-mechanical, and thermo-optical properties of the mesh have a direct impact on the performance of the microwave instruments. Metal mesh material is, in general warp knitted, textile fabric to achieve good elastic properties while having a high density of wire required by the RF reflectivity at Ka-band. Several types of warp knitted mesh have been manufactured and characterized from both RF and mechanical point of view. The paper gives an overview of the typical mesh requirement needed for Ka-band applications. Then the paper details the different challenges to produce a high frequency RF reflective mesh and to characterize it. It also gives a brief description of the mesh patterns that have been produced and characterized. Finally, the RF and mechanical characterization measurement results of the best performing meshes are presented.