Design of Low Noise Amplifier for 1.5 GHz

Abstract

Low Noise Amplifier (LNA) is a front-end device of a radio frequency (RF) receiver used to increase the amplitude of an RF signal without much additional noise, thereby increasing the noise figure of the system. This paper presents design, simulation, and prototype of an LNA operating at 1.5 GHz for the bandwidth of 100 MHz. The circuit was simulated using Advanced Design System (ADS). The components used are Surface Mount Devices (SMDs); with transistor "Infineon BFP420" as a major component. Other components are resistors, capacitors, and inductors; inductors being superseded by microstrip lines. The circuit was fabricated on FR4 board. The measurements of several parameters of LNA were made using Vector Network Analyzer (VNA), Noise Figure Meter; and Spectrum Analyzer. The LNA has minimum gain of 15.4 dB and maximum noise figure of 1.33 dB. It is unconditionally stable from 50 MHz to 10 GHz. DC supply is 5V and the current consumption is 10 mA. This LNA offers Output-Third­Order-Intercept-Point (OJP3) of about 1 4 dBm.