A Narrow-Band CMOS LNA for Wireless Communications

Abstract

In this paper, a narrow-band low-noise amplifier (LNA) is described in 180nm digital CMOS technology. By means of an inductive degenerated common source amplifier with a gate inductor gives an excellent input matching. The output matching is obtained by using the output stage including output buffer. In the proposed LNA, the cascode technique is adopted in order to improve the noise figure and isolation. The LNA provides high gain and low noise figure and good reverse isolation over the frequency range as well as good stability. The LNA is simulated with a TSMC 0.18-J.lm CMOS technology. The input and output reflection coefficients are −16.45 dB and −16.92 dB at an operation frequency of 10 GHz, respectively. The noise figure of the LNA remained under 2.95 dB from 9.75 GHz to 10.25 GHz with minimum value of 2.8 dB. Additionally, a high gain with average value of 14.44 dB and a maximum value of 15.69 dB is achieved for the whole bandwidth of 500 MHz. The power consumption at 1.8-V supply voltage without an output buffer is only 8.44 mW.