Millimeter-Wave SPDT Switch MMICs With Travelling Wave Concept

This paper describes the design of a D-band wideband SPDT switch using 60nm GaN HEMT technology. The broadband characteristic has been realized by using the parasitic capacitance of the off-state HEMTs to form an artificial transmission line. The equivalent circuits of the on and off state HEMTs are developed and the design parameters of the traveling-wave switch have been calculated. The simulation results demonstrate that the insertion loss is less than 7dB, minimum Isolation on off state is 20dB over 130~150GHz, the chip size is 1.5mm*1.5mm.