Simple impedance transforming feed system for low-gain quadrifilar and bifilar satellite terminal antennas

摘要

An impedance transforming balun feeder system has been devised for low-gain antennas such as quadrifilar helices and spirals, consisting of four coaxial cables and a microstrip circuit. The arrangement allows physically orthogonal 'balanced pair' outputs with quadrature phasing, in space limited configurations.