Broadband array element with polarization multiplexing at K-band

A multilayer K-band patch antenna is presented. It offers the possibility to differentiate incoming signals by means of polarization. Based on a previously presented radiating element with high polarization purity, an effective approach to extend the functionality of such a fixed polarization design is proposed. The resulting two-port fed antenna features polarization multiplexing division (PMD) property without the usage of hybrid couplers. Compared to the one-port design it does not require additional layers. A left- and right-handed circularly polarized (LHCP/RHCP) antenna is designed. The enhanced two-port design fed on the same layer is analyzed and simulation results are discussed based on an equivalent circuit. Finally, measurement results of a fabricated multilayer antenna with vertical transitions are reported.