A Low Noise Figure LNA Design and Simulation for Ultra-Wideband Communication

This paper deals with the design of low noise amplifier (LNA) for Frequency Modulated Ultra-wideband (FM-UWB) transceiver system with a frequency range of 3.5-4 GHz, covering a bandwidth of 500 MHz. Most of the designs in existing literature deals with design for entire UWB range of 3.1-10.6 GHz and such bandwidth is not useful for optimised power performance in FM-UWB. Also out of band interference cannot be suppressed. So a design for a lower UWB range is being preferred. Among the existing designs for lower range, high gain is achieved at the expense of higher noise figure. Here a stacked architecture of three stages is used which achieves optimum gain and noise performance. Implementation is done using Agilent ADS software. An average LNA gain of 29.25 dB and a noise figure <0.4 dB is obtained.