A 29-48 GHz Variable Gain Low Noise Amplifier Using Active Load in 90-nm CMOS Process

This paper presented a broadband (29-48 GHz) variable gain low-noise amplifier (VGLNA) with variable power consumption in 90-nm CMOS technology. A tunable active load is used for gain control and reduce power consumption in low gain states. In order to reduce the noise factor, the source degeneration technique is utilized with the goal of optimizing both noise and input matching. The tunable active load can not only reduce the power consumption but also minimize the variation of noise figure. A measured peak gain of 19 dB with 3-dB bandwidth from 29-48 GHz and an 8-dB gain control range are achieved. The measured minimum noise figure is 5.3 dB with very little variation in different gain states. The measured of IP1dB drops from -16 to -17 dBm when tuned from high gain to low gain mode, while consuming 13.8-24.7-mW dc power.