Patent ID: 6608604
Filing Date: 2003-08-19
Classification: H01P,H01Q

Abstract:
A helix antenna with integrated duplexing means, characterized in that it comprises two decoupled coaxial helices, each formed by radiating strands printed on a substrate, each of said helices being associated with a distinct supply structure, each supply structure being an independent, miniaturised structure for the wideband supply of said radiating strands, said supply structures being printed on said substrate and comprising at least one hybrid coupler made out of semi-localised elements, said semi-localised elements being designed according to the following steps:designing said coupler with conventional distributed stripline elements, each of them having at least a &lgr;/4 length; turning each of said distributed stripline elements into lumped elements, each of them being a &pgr; cell made of one capacitance C and two inductances L,Lâ€²; and turning each of said capacitances and inductances into semi-localised elements, each of said inductances being turned into a reduced width line and each of said capacitances being turned into a larger width line, each of said lines being smaller than &lgr;/4.