FOUR-PORT BALANCED ANTENNA FEEDING NETWORK FOR SWITCHABLE POLARIZATIONS AND STABLE TX/RX ISOLATION CHARACTERISTICS

Abstract

A new four-port balanced antenna feeding network for switchable polarizations and high transmit/receive (Tx/Rx) isolation characteristics is presented. The proposed structure is configured by two switching mode hybrid matrices which consist of two 3-dB couplers and two SP4T switches, two directional couplers, and Wilkinson dividers. By controlling impedances of the switching mode hybrid matrices, different types of polarizations such as right-handed circular polarization, left-handed circular polarization, vertical polarization, and horizontal polarization can be generated with stable Tx/Rx isolation characteristics regardless of antenna impedance variations. (c) 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:17-23, 2014