An effective design of two stage low noise amplifier for WiMAX

An efficient two-stage low noise amplifier (LNA) is designed around 3.5 GHz spectrum of WiMAX. The first stage of LNA is designed using pseudomorphic high electron-mobility transistor (pHEMT).The pHEMT GaAs FET is conditionally stable within the desired frequency range of 3.3 GHz to 3.5 GHz. The simulated results were obtained at 3.4 GHz for gain of 24.3 dB, noise figure (NF) 1.13 dB, input return loss (S 11 ) greater than 28 dB and output return loss (S 22 ) nearly 29 dB. The LNA is fabricated by using RT-duroid substrate with epsiv r =2.55 and the designed results were well matched with the simulated results.