A 19–31GHz K/Ka-band Broadband Low Noise Amplifier with High Gain and High Flatness

This paper describes a design of high flatness broadband monolithic microwave integrated circuit low-noise amplifier (LNA) based on 100-nm gallium-nitride-silicon-carbide (GaN-on-SiC) technology for 19-31 GHz. Common-source (CS) configuration with inductive degeneration has been used for all transistors to fit the input match and noise figure (NF). A parallel RC network and broadband matching networks have been used simultaneously to achieve improved gain flatness at a wide frequency band. The proposed three-stage LNA with a chip area of 2.1×1.3 mm² exhibits a low NF of 1.4-1.8 dB, a high gain of 20.1-21.1 dB and a gain flatness of ± 0.5 dB. At 26GHz, the output 1-dB compression point (OP1dB) and output third-order intercept point (OIP3) are 20.8 and 32.3 dBm, respectively.