Active Inductor Based Differential Low Noise Amplifier for Ultra Wide Band Receiver

Abstract

receiver is proposed. A fully differential topology has been adopted for both LNA and AI in order to improve the circuit robustness against unwanted common mode signals. T-coil peaking is used to enhance the bandwidth of LNA over the entire UWB frequency range. AI has been used because of its low area, tunable inductance and high quality factor. The proposed LNA is designed using 90nm CMOS technology. The figure of merits of the LNA with passive inductor and with Active Inductor are analyzed and compared. This LNA achieves power gain (S 21) greater than 13dB throughout the UWB spectrum providing a 3-dB bandwidth of 2-11 GHz. The input matching (S 11) and output matching (S 22) are kept well below-20 dB and-8dB respectively, while the reverse isolation (S 12) is less than-53 dB. The noise figure of this LNA reaches 8dB due to increased number of stages and addition of Active Inductor.