Linear Polarization Control for Shared Aperture SATCOM Systems at Ku-Band

This paper presents a new phase-shifting duplexer architecture for passive linear polarization control. The duplexer is based on reflective-type phase shifters employing Lange couplers and back-to-back varactor diode configuration, allowing simultaneous polarization rotation, low insertion loss, and high TX-RX isolation across frequency and polarization angles. Closedform expressions of the system operation are proposed, followed by comprehensive performance validation of a full EM structure simulation on alumina substrate and actual varactor models.