Design of a Variable Gain LNA Applied in CMMB

A variable gain low noise amplifier (LNA) has been implemented in 0.13μm CMOS technology to support CMMB standards.This LNA works from 2.635 GHz to 2.66 GHz,and is divided into low gain mode and high gain mode which is mainly used.With the help of cadence software,pre-simulation and post-simulation was done.And then the chip was taped out and packaged before being measured.Chip measurement shows that,in the mainly used high gain,S₂₁ is from 9.25 to 9.42 dB,NF is from 1.99 to 2.26 dB,IIP3 is 1.25 dB.Power dissipation is 7.38 mW with while the power supply is 1.2 V.In the low gain,S₂₁ is from-5.85 dB to-5.70 dB,NF is from 7.90 dB to 8.99 dB,IIP3 is 14.19.