Fusion Design of Cryogenic Filtering Low-Noise Amplifier With High Out-of-Band Rejection Assisted by Grey Wolf Optimizer

A cryogenic filtering low-noise amplifier (LNA) using 100-nm InP technology is presented in this letter. Fusion design method is utilized to incorporate filtering functionality seamlessly into LNA without adding extraneous noise and or occupying excessive chip area. The grey wolf optimization (GWO) algorithm is employed to increase the design efficiency and optimize the circuit performance. Experimental results demonstrate the 4–8-GHz filtering LNA at 5 K achieves a gain of 33.6 ± 1.5 dB and an average noise temperature of 4.8 K with a minimum noise temperature of 3.5 K at 4.4 GHz. Multiple zeroes are generated, leading to an out-of-band rejection of over 60.7 dB across 0–2 GHz and 50.9 dB from 12 to 30 GHz.