Sieganschin, AntonAntonSieganschinJaschke, ThomasThomasJaschkeMitto, Hans K.Hans K.MittoLamann, Nadja JaninkaNadja JaninkaLamannWaldhelm, JanJanWaldhelmJacob, ArneArneJacob2019-05-272019-05-272019-04-23GeMiC 2019 - 2019 German Microwave Conference : 51-54 (2019-04-23)http://hdl.handle.net/11420/2722This contribution deals with a compact substrate integrated waveguide (SIW) diplexer for terminal array antennas at K-/Ka-band. The diplexer connects the transmit (Tx) and the receive (Rx) frontend with an antenna element. It is comprised of a bifurcation and two second order bandpass filters with low insertion loss. The Rx-filter has additionally two transmission zeros in the Tx-band. The structure is implemented in multilayer printed circuit board (PCB) technology. This yields a compact design which can be integrated in an array with half-wave element spacing. The simulated diplexer performance is validated by measurements. The insertion loss in the Rx-band remains below 0.7 dB, while the Tx-/Rx-isolation exceeds 40 dB in a 1.2 GHz band at Tx.enConference Paper10.23919/GEMIC.2019.8698160Other