Dual UHF dipole quadrafiler helix antenna

A dual UHF/GPS antenna system comprising:

• a UHF dipole antenna structure comprising an upper tubular section and a lower tubular section;
• a lower coaxial feedline wherein the outer conductor of the lower coaxial feedline is configured to feed the upper section of the dipole antenna structure and the inner conductor of the lower coaxial feedline is configured to feed the lower section of the dipole antenna structure;
• an upper coaxial feed line configured to access the upper section through the lower section of the dipole antenna structure, and
• a GPS antenna stacked on top of said dipole antenna structure and fed with the upper coaxial feedline, said GPS antenna having said upper tubular section as a ground plane, wherein there is a coil which include at least seven turns of the upper and lower coaxial feedlines around a nonconductive part of the dipole antenna structure.

A dual UHF/GPS antenna system comprising:

• a UHF dipole antenna structure comprising an upper tubular section and a lower tubular section;
• a lower coaxial feedline wherein the outer conductor of the lower coaxial feedline is configured to feed the upper section of the dipole antenna structure and the inner conductor of the lower coaxial feedline is configured to feed the lower section of the dipole antenna structure;
• an upper coaxial feed line configured to access the upper section through the lower section of the dipole antenna structure, said coaxial feedlines coiled at the bottom of said lower section of said dual dipole structure and overlain with a strip of conductive tape, wherein there is a coil which includes at least seven turns of the upper and lower coaxial feedlines around a nonconductive part of the dipole antenna structure;
• and
• a GPS antenna stacked on top of said dipole antenna structure and fed with the upper coaxial feedline.

A dual UHF/GPS antenna system comprising:

• a UHF dipole antenna structure comprising an upper tubular section and a lower tubular section;
• a lower coaxial feedline wherein the outer conductor of the lower coaxial feedline is configured to feed the upper section of the dipole antenna structure and the inner conductor of the lower coaxial feedline is configured to feed the lower section of the dipole antenna structure;
• an upper coaxial feed line configured to access the upper section through the lower section of the dipole antenna structure, said coaxial feedlines coiled at the bottom of said lower section of said dual dipole structure and overlain with a strip of conductive tape;
• and
• a GPS antenna stacked on top of said dipole antenna structure and fed with the upper coaxial feedline, wherein said coiled coaxial feedlines and said strip form an LC circuit for lowering the operating frequency of said dipole.

A dual UHF/GPS antenna system comprising:

• a UHF dipole antenna structure comprising an upper tubular section and a lower tubular section;
• a lower coaxial feedline wherein the outer conductor of the lower coaxial feedline is configured to feed the upper section of the dipole antenna structure and the inner conductor of the lower coaxial feedline is configured to feed the lower section of the dipole antenna structure;
• an upper coaxial feed line configured to access the upper section through the lower section of the dipole antenna structure, said coaxial feedlines coiled at the bottom of said lower section of said dual dipole structure and overlain with a strip of conductive tape;
• and
• a GPS antenna stacked on top of said dipole antenna structure and fed with the upper coaxial feedline, wherein the upper section of said dipole antenna structure serves as a ground plane for said GPS antenna.