An Active Shaping Reflector Method for Space-Borne Membrane Reflector Antennas

Conventional space-borne antenna shaping designs predominantly rely on a pre-defined reflector geometry, which lacks the capability to adapt to varying multi-stage service requirements once in orbit. To overcome this limitation, this paper proposes an active shaping method for space-borne membrane reflector antennas (MRA) through coordinated control of electrostatic forces and boundary cable tensions. A coupled structural-electromagnetic model is established that integrates the nonlinear finite element method for structural mechanics and the physical optics approach for radiation analysis, capturing the interactions between actuation forces, reflector morphology, and far-field performance. With electrostatic voltages and cable tensions as design variables, an optimization model is formulated to minimize the root mean square error of the directivity at sample points within the target coverage region. Numerical simulations conducted on a 30-meter aperture MRA demonstrate the effectiveness of the method, achieving an average directivity improvement of approximately 2.67 times after active shaping. The approach provides a feasible strategy for in-orbit reconfiguration of membrane reflector antennas to accommodate dynamic mission profiles and was verified through experiments with 5-meter electrostatically formed MRA.