Innovative Visually Covert Antennas

This proposal describes an innovative technical approach for the design and development of visually covert, low-power, low-gain antennas operating in selected portions of the 2-200OMHz frequency band. Our approach is two-fold: firstly, we propose to use planar radiating elements that (a) incorporate continuous impedance loading to extend the normal operating range or (b) have inherently broadband properties at the higher frequencies of interest; and secondly, we propose fabricating the antennas by sputtering or etching the antenna elements onto flexible plastic sheets that can be covered with a thin anti-reflective coating to further reduce the visual signature. This combined approach results in antennas with impedance characteristics that can be matched with a small fixed network or by a simple impedance transformation and are visually covert. The proposed antennas can be incorporated into the fabrication of composite or other non-conducting parts (Class I antennas) or easily affixed to conducting or non-conducting areas of a platform with minimal surface preparation (Class II antennas). Anticipated Benefits/Potential Applications - Military applications include: remote tracking and monitoring; mission protection and clandestine operations; concealing within soldier's clothing. Commercial appeal for general aviation, pleasure boating, cellular telephones in automobiles, and remote tracking of vehicles such as delivery trucks, trains and shipments of hazardous waste.