A novel UWB low-noise amplifier design using double capacitor cross-coupled feedback

Abstract

In this paper, an ultra-wideband (UWB) low noise amplifier (LNA) with improvement in noise figure (NF) and gain flatness using 0.18-um RF CMOS technology is presented. Two cross-coupled capacitors (CCC) and new gain flattening technique in a cascode common-gate structure are used for NF and gain flatness improvement, respectively. In addition, NF calculation of CCC cascode common-gate amplifier is presented considering the noise of cascode stage. The LNA operates from 3.1 GHz up to 10.6 GHz with no change in power consumption compared with conventional one. The proposed LNA achieves average S21 of 21dB and S11 less than −10 dB in the entire bandwidth. Additionally, the minimum NF of 2.38 dB is achieved. Furthermore, the power consumption at 1.8 V supply voltage is 4.34 mW and the core layout size for proposed LNA using CCC with and without including new gain flattening techniques are 881μm×1201μm and 680μm×733μm, respectively.