A robust and portable reflector antenna

This paper describes an inflatable parabolic antenna system for truly portable Internet access. Our first development is a dish 1 m in diameter that has a lightweight aluminium positioner support. Inflatable antennas are not new, but they have historically been proposed to overcome payload weight reduction and deployability issues at the spacecraft-end of the communication link. Our antenna comprises an inflatable outer torus that becomes very rigid at its deployed pressure of 6 p.s.i. Inelastic metalised film is used for the reflecting surface. During construction the film is heat-formed under vacuum onto a parabolic mould. The finished antenna is a sealed-air system with a front face made from a thin laminate. This has excellent radio frequency transmission properties up to and beyond 18 GHz. When inflated, the heat-formed layer takes on the parabolic shape to an accuracy that permits high antenna efficiency beyond 18 GHz