A 24-GHZ active SPST MMIC switch with InGaP/GaAS HBTS

Abstract

A 24-GHz single-pole, single-throw (SPST) switch with high isolation is designed using InGaP/GaAs HBT process. To obtain high isolation in an off state, cascode structures are utilized and an additional shunt transistor is introduced in an output, which helps to reject a leakage signal. Dummy cascode structure is used as a current steering circuit for input matching and short rise/fall time. The fabricated SPST switch shows an effective isolation of similar to 52 dB at 22.8 GHz and 41 dB at 24 GHz. (C) 2008 Wiley Periodicals, Inc.