Ultra-wideband low noise amplifier using a cascode feedback topology

An ultra-wideband (UWB) low-noise amplifier (LNA) that consists of two cascode and shunt feedback stages is presented. The measurement results show the maximum gain (S-21) of 9 dB with the from 2 to 6.5 GHz and return losses (S-11, S-22) of less than 3-dB band -7.8 dB from 2 to 11 GHz. In addition, the fabricated LNA achieves the average noise figure (NF) of 4.5 dB from 2 to 10 GHz which value is much lower than previously reported state-of-art UWB amplifiers. The input-referred 3(rd)-order intercept point (IIP3) and the input-referred 1-dB compression point (P-1dB) of the LNA are achieved as 4 and -5 dBm, respectively, while consuming 27 mW in the 0.18-mu m RF CMOS process. (c) 2006 Wiley Periodicals, Inc.