In tile T/R module,the vertical transmission of RF signal from module cavity to radiating unit outside has a great influence on performance of the whole structure.A method is proposed to realize effective vertical interconnection.Microstrip in the cavity is connected to radiating unit through offset strip line,coaxial vias,Sn balls,vias in the lid and mini-SMP connector.The whole structure is simulated and optimized with EM simulation software HFSS.Parameters of emphasized structures are determined.LTCC til...