Antennelement, koniskt helixformat, för polarisationsrenhet inom brett frekvensområde

摘要

PCT No. PCT/SE96/00767 Sec. 371 Date Dec. 17, 1997 Sec. 102(e) Date Dec. 17, 1997 PCT Filed Jun. 12, 1996 PCT Pub. No. WO97/01196 PCT Pub. Date Jan. 9, 1997An antenna element including a ground plane. A support supports a conical structure. The support is made of a dielectric material. A bottom portion of the support is attached to the ground plane. Four conical radiation means are symmetrically arranged around the support. Each radiation elements includes a helical wire having a top end and a bottom end. The bottom ends of the radiation elements are attached to the ground plane. Four coaxial cables including conductors are provided. One coaxial cable is connected to the top end of each radiation element for providing each radiation element with a microwave signal for emitting two orthogonally polarized radiations. A distribution network divides an incoming signal into four subsignals offset in phase in relation to each other. One of the subsignals is provided to each of the four radiation elements. Adaption elements adapts an output impedance of the distribution network to an input impedance of the radiation elements. The adaption elements include four channels and the conductor of one of the coaxial cables extending therethrough. Each channel extends through a metal block.