Stabilization of Phased Focus Array Using Electrochromic Technology

"Future space-based radar systems (SBRS) are expected to be critical to defense intelligence and modern battlefield analysis. SBRS design concepts involve thermal control issues exacerbated by low thermal mass, high radiative losses, and pressure to meetdesign areal densities of 4 to 6 kg/m2. To address these issues Eclipse Energy Systems, Inc. has developed prototype designs for electrochromic devices with areal densities of 0.3 kg/m2 to replace louvers in controlling solar absorption and IR emittance ofSBRS while minimizing energy expenditures. The program is innovative in developing flexible Variable Emittance Devices (VEDs) composed of a monolithic stack of solid state inorganic materials, having no moving parts that can withstand the harsh spaceenvironment. Phase I results demonstrated the feasibility of fabricating VEDs capable of altering the effective emittance of antenna components. The Phase II program will develop VEDs suitable for commercial application on rigid silicon and germaniumsubstrates and on flexible polymer substrates. Prototypes will be tested under simulated load conditions to determine design parameters for thermal and mechanical engineers. Efforts will also be made to improve the structural and optical characteristics ofthe electrochromic layers to achieve acceptable performance and longevity in the space environment."