A Multi-Band LNA Covering 17–38 GHz in 45 nm CMOS SOI

This paper presents a multi-band low-noise amplifier (LNA) in the 45-nm CMOS silicon-on-insulator (SOI) process. The LNA consists of three stages, with the differential cascode amplifier as the core structure. The first stage is mainly responsible for input matching to ensure favourable noise characteristics and bandwidth, while the subsequent stages increase the gain. Moreover, the LNA utilizes baluns for input/output and interstage impedance matching. Switch capacitances are added to switch the three operating bands of the LNA, which cover 17–38 GHz overall. Measurement results show that the proposed LNA achieves a gain (S21) of 23.0 dB and a noise figure (NF) of 4.0 dB.