Low Noise Figure, High Gain Single LNA Cascaded with Cascoded LNA Amplifiers using Optimized Inductive Drain Feedback for Direct Conversion RF Front-end Receiver at Wireless Application

摘要

This study presents a design of low noise figure, high gain LNA at 5.8 GHz with cascaded and cascoded techniques using inductive drain feedback that is applicable for the WiMAX 802.16 standard. The amplifier uses Pseudomorphic High Electron Mobility Transistor FHX76LP super HEMT low noise FET. The Ansoft Designer SV as an Electromagnetic (EM) simulator was used during the design process. The LNA was designed using the inductive drain feedback, inductive generation to the source and the T-network as a matching technique was used at the input and output terminal. The cascaded and cascoded Low Noise Amplifier (LNA) produced a gain (S21) of 43.94 dB and the Noise Figure (NF) of 0.61 dB. The input reflection (S11), output reflection (S22) and return loss (S12) are -10.65, -20.02 and -52.23 dB, respectively. The measured 3 dB bandwidth of 1.24 GHz has been achieved. The input sensitivity is -84 dBm exceeded the standards required by IEEE 802.16 has been observed.