The AstroMesh deployable reflector

The AstroMesh is a mesh reflector for large aperture space antenna systems. It embodies a new concept for deployable space structures: a pair of ring-stiffened, geodesic truss domes, in which the ring is a truss deployed by a single cable. Compared to other mesh reflectors, the AstroMesh achieves uncharacteristically low levels of total mass, stowed volume, surface distortion, cost, and program schedule duration. Several large AstroMesh reflectors are being produced for a series of US built commercial geosynchronous mobile communications spacecraft; first flight is planned for early 2000. The AstroMesh mounted on the Euro-African Satellite Telecommunications (EAST) system, an example of a large aperture mobile communications satellite conceived by Matra Marconi Space, is depicted. Two large models have been qualified for space flight with as-manufactured shape errors of less than D(6/spl times/10/sup -5/) RMS, and repeatability errors below D(5/spl times/10/sup -5/) RMS (where D is the aperture diameter). With current materials and manufacturing techniques, the AstroMesh design can achieve a surface accuracy from all error sources, including in-orbit environments, of D(2.5/spl times/10/sup -5/) RMS. Large margins on a very demanding passive intermodulation (PIM) specification have been achieved consistently.