High linearity SPDT switch for dual band wireless LAN applications

This paper presents a high linear and power-handling single-pole double-throw (SPDT) switch for WLAN 802.11 a/b/g applications. The switch circuit has asymmetric and stacked topology to have high power-handling and linearity for the Tx path. This SPDT switch has been implemented with 0.25 μm GaAs pHEMT process by ETRI. The designed SPDT switch has the measured insertion loss of better than 1dB and isolation of better than 40dB for the Tx path and 25dB for the Rx path and the high power handling capability with P_1dB of about 23dBm with control voltage of -3/0 V. The fabricated SPDT switch chip size is 1.8 mm × 1.8 mm.