Investigation of microwave active elements embedded in composite structures

Multifunctional structures have become popular within the past decade as they allow for more efficient utilization of limited real-estate available on many civilian and military platforms. Taking structures and electromagnetics, one can marry these two fields to produce a weight optimized loadbearing microwave structure which may ideally be suited for unmanned aerial systems. This paper investigates the use of textile processes to develop loadbearing smart skins built into a class of structural conformal composite materials called pre-pregs (resin pre-impregnated fabrics). An example of an active UWB mini-circuits ERA-4SM+ (0-4 GHz) amplifier has been investigated within a 48 g.m^-2 pre-preg structural glass material (HexPly914E). This amplifier has been embroidered and cured at 170°C in an autoclave at 700 kPa pressure. Its performance before and after curing has been examined.