Patent ID: 7209096

Claim:
A low-visibility, field-diverse dual band monopole antenna for providing communications comprising: an antenna-supporting core comprising printed circuit board (PCB) substrate and having a width and a length; an antenna, said antenna wrapped upon said core in a manner for two selected dual band resonant frequencies, said antenna radiating in a diverse manner with horizontal and vertical field components of a field radiated by said antenna substantially in phase and not circularly polarized; said antenna including a two-pole low-pass filter that enables operation at said two selected resonant frequencies, said two-pole low-pass filter including three passive components that enable operation at said two selected resonant frequencies; and said three passive components including: an adjustable conducting foil acting as an inductor, said conducting foil enabling operation at said two selected resonant frequencies; and a first capacitor and a second capacitor system selected from the group consisting of: first and second capacitors matching the remainder of the circuit to enable operation at said two selected resonant frequencies, first and second capacitors coupled to a tuning inductor to enable operation at two selected resonant frequencies, first and second capacitors coupled to a micro-strip to enable operation at said two selected resonant frequencies, and combinations thereof; whereby the low-visibility, field-diverse dual band antenna is realized having helical antenna characteristics without severe circular polarization radiation thereby promoting reliable communications.