Design of a Two Stage Low Noise System in the Frequency Band 1.8 2.2GHz

In first stage of each microwave receiver there is Low Noise Amplifier (LNA) circuit, and this stage has important rule in quality factor of the receiver. This paper presents the design of LNA and development of low bias (VD=3V, ID=20mA), the LNA operating in frequency range 1.8-2.2GHz using a feedback circuit. Design System (ADS) 2012 tool was used for design and simulation, and each design was tuned to get the optimum value for NF, power gain (S21), input return loss (S11) and reverse isolation (S12). Simulation results have indicated that the S21 achieves 33.2515±0.4475dB over the wide frequency band of 1.8-2.2GHz, the gain was almost flat over the whole band. Noise Figure (NF) maintains is 0.4945±0.0565dB, S12 < -47.089dB and S11 < -16.126 dB in the entire band.