A Novel 2.4 GHz CMOS Variable Gain Low Noise Amplifier Design for Bluetooth and Wireless LAN Applications

This paper describes a 2.4 GHz fully differential variable gain low noise amplifier (VGLNA) in a 0.18-mum CMOS process. The VGLNA achieves a maximum small signal gain of 18.37 dB within 1-dB compression point (iCP_1dB) of -11.35 dBm and a minimum gain of 6.4 dB. In the high gain mode, the noise figures (NF) is 2.1 dB with good input return loss. The LNA's IIP3 in the high gain mode is 2.47 dBm. The LNA consumes only 4.3 m A of current from a 1.5-V power supply.