An 8 GHz Variable Gain Low Noise Amplifier (VGLNA) Utilizing Parallel Inter-Stage Resonance

Abstract

A two-stage variable gain low noise amplifier (VGLNA) topology is proposed, which adopts a parallel interstage resonance. The characteristics of the parallel inter-stage resonance in gain enhancement are analyzed and this is then followed by the application of a simple circuit consisted of two transistors as the variable gain stage. The VGLNA is designed and simulated based on a 0.18 gm CMOS technology for 8-GHz X-band applications. Simulation results show 13.63 dB of power gain, 3.60 dB of noise figure, 4.27 dBm of 11P3 and dc power supply of 1 V with 35.67 mA current drawn.