A low voltage Q-band CMOS LNA with magnetic coupled cascode topology

In this paper, a Q-band low noise amplifier (LNA) is designed using in 90-nm low power (LP) CMOS. This LNA achieves a high gain and low noise. Besides, a transformer is placed between the cascode devices to reduce the noise figure and enhance the stability, as well as also bandwidth. The LNA features a maximum small signal gain of 13.8 dB and a minimum noise figure of 3.8 dB at 37 GHz, with a power consumption of 18mW. The chip size is 0.93 × 0.52 mm², including all the testing pads. To the best of our knowledge, this is the first magnetic coupled cascode LNA in Q-band reported to date.