Patent ID: 7245268

Claim:
A quadrifilar helical antenna, comprising: a substrate having a first substrate region and a second substrate region spaced apart therefrom; a first helical filar having a first length extending between a first filar end and a second filar end, the first filar end disposed at the first substrate region, the first filar extending along an outside surface of the substrate in a helical pattern to the second substrate region and further extending along the outside surface in a helical pattern from the second substrate region back to the first substrate region where the first filar terminates in the second filar end; a second helical filar having a second length different from the first length, the second length extending between a third filar end and a fourth filar end, the third filar end disposed at the first substrate region, the second filar extending along the outside surface of the substrate in a helical pattern to the second substrate region and further extending along the outside surface in a helical pattern from the second substrate region back to the first substrate region where the second filar terminates in the fourth filar end; and an impedance matching element conductively connected to the first, second, third and fourth filar ends for matching an antenna load impedance to a source impedance.