Design of Dual Band Low Noise Amplifier for Next Generation Indoor Access Point Receivers

Low-Noise Amplifiers (LNA) are key components in the receiving end of nearly every communications system. They do improve the gain and add very less noise to the amplified signal compared to others circuits in the receivers. The purpose of this project is to design a Dual Band Low Noise Amplifier (LNA) working at the frequency range of around 2.4 GHz and 5.2 GHz, by using an ultra-low- noise Pseudomorphic High Electron Mobility Transistor (PHEMT) from Avago Technologies. To improve the design of the dual band, it is necessary to build a two-stage cascade amplifier, one stage is to work in minimizing noise sensitivity, and another stage to get the maximum gain achievable by the transistor. The wanted input signal of these systems is usually very weak and the primary purpose of the LNA is consequently to amplify the signal while at the same time adding as little additional noise as possible. Its performance is measured in a number of figures of merit among which gain and noise figure are most notable while dynamic range, return loss and stability are examples of others.