Design of a Broadband High Gain Full Active Bias LNA With Improved Noise Figure for OTH Radar’s Receiver Application

This paper introduces a High Frequency (HF) band, Continuous Wave (CW), High Gain, Broadband Low Noise Amplifier (LNA) implemented using silicon-based Bipolar Junction Transistor (BJT) technology on a single board. This LNA will be used in the receiver section of an Over The Horizon (OTH) Radar and is capable of working in the entire HF band i.e. from 3 MHz to 30 MHz. Class-A configuration of amplifier design is been used here with a completely Active Biasing technique. A gain of more than 28 dB for a single stage is been achieved and the noise figure (NF) of the circuit is less than 2.5 dB in the entire range of operation. Also a mathematical analysis has been done to showcase the improvement in noise figure. This novel design is not only limited to OTH Radar but also can be used for Amateur Radio Communication and Ionosonde Experiments purpose.