Abstract:
In this paper the design of a fully concurrent dual-band (900/1800MHz) low-noise amplifier (LNA) is presented, the main aim is to bring the noise figure below 3dB to improve the performance of modem receivers. Two single band LNAs operating at GSM 0.9GHz and Digital Cellular System (DCS) 1.8GHz are separately designed using traditional method firstthen both single-band matching networks aremerged, one dual-band matching network (MNs) of the dual band LNA is designed at (900MHz and 1800MHz). This is a single stage amplifier. The dual band LNA is designed to provide low noise figure. The fully concurrent LNA circuit designed using BFG520 Transistor technology, and simulated in Advance Design System (ADS) of version 2009A. For use in multi-standard wireless receiver frontend the proposed design is very useful because the noise figure obtained is suitable for the better performance. The simulation results show that single band LNA at 900 MHz gives the Noise figure of 1.2dB while at 1800MHz it is increased to 2.6dB, the dual band design provides the Noise figure of 1.19dB and 2.71dB for 900MHz and 1800MHz respectively, using 100mA current from 9V power supply with the power consumption of 0.9 Watt.
