2.4/5.5GHz LNA switch designs based on high resistive substrate 0.35um SiGe BiCMOS

In this paper, we present 2.4/5.5 GHz LNAs with SPDT Switch for WiFi Front-End Modulate Integrated Circuit (FEM IC) based on high resistivity substrate 0.35um SiGe BiCMOS process. For the 2.4GHz LNA, the bias circuit's effect on the nonlinearity is analyzed and measured, and then a new bias circuit is proposed. With 2.7V supply, it consumes 4.2mA current. The measured Gain is about 14.6dB with input and output return loss better than −10dB. The Noise Figure (NF) is 1.16dB, output 1dB compression point is ∼8dBm, and OIP3 is about 20dBm. For the 5.5GHz LNA with proposed new bias circuit and SPDT switch operating at 7.3mA current with 2.7V power supply, 2.1dB NF and 19dBm OIP3 are achieved in the post layout simulation.