Abstract: A nove limplementation of high frequency switch matrix for satellite usage was proposed by using substrate integrated waveguide (SIW)technology in low temperature co-fired ceramic (LTCC)fabrication process.The SIW channels transition between layers and isolation capability between different channels were discussed.By utilizing the single-pole-double-throw switch chips as channel choosing units,and SIW channels as the radio frequency signal transition, connection and cross transmission channels,a K band 4x4 switch matrix was designed and measured,with insertion loss less than 8 dB and isolation more than 38 dB from 20 GHz to 21 GHz,which showed good transition performance within SIW RF channels and high isolation between adjacent  RF  ways in high frequency,to solve the conundrum that high frequency switch matrixin LTCC always have high insertion loss and low isolation,asthe higher
radiation loss and lower isolation capability of the strip-line embedded in LTCC substrate.

Key words: Switch matrix, Substrate integrated wave guide, Low temperature co-fired ceramic, Satellitec ommunication