Patent ID: 6075501
Filing Date: 2000-06-13
Classification: H01Q

Abstract:
A helical antenna comprising a cylindrical dielectric member, m members of a first helical conductor which are wound around an outer wall of said cylindrical dielectric member, m representing a natural number, said m members of the first helical conductor covering a first frequency band, n members of a second helical conductor which are attached to an inner wall of said cylindrical dielectric member, n representing a natural number, said n members of the second helical conductor covering a second frequency band, a first power supply circuit for supplying high-frequency powers to said members of the first helical conductor on the outer wall of said cylindrical dielectric member, and a second power supply circuit for supplying high-frequency powers to said members of the second helical conductor on the inner wall of said cylindrical dielectric member,wherein an angle of each of said m members of the first helical conductor relative to a horizontal direction is different from an angle of each of said n members of the second helical conductor relative to the horizontal direction, andwherein a length of each of said m members of the first helical conductor is different from a length of each of said n members of the second helical conductor,whereby a beam radiation direction of said first frequency band is the same as a beam radiation direction of said second frequency band.