Abstract
A good design of LNA for S band satellite navigation receivers and 4G LTE wireless communication system has been implemented in this paper. Due to increased congestion in the present L band, the S Band frequency from 2483.5-2500 MHz has been allocated for the future satellite navigation systems. For this purpose ATF-34143 amplifier (pHEMT) having high electron mobility and fast switching response has been chosen due to its very low Noise Figure (NF). The amplifier has been designed having bandwidth of 0.8 GHz from 1.8-2.6 GHz. Because of the large bandwidth, the amplifier could serve many wireless communication applications including 4G LTE mobile communication at 2.1 GHz. The design was implemented using the micro strip technology offering extremely low noise figure of 0.312 dB and 0.377 dB for 2.1 GHz and 2.49 GHz respectively. The gain of the amplifier was low and found to be 10.281 dB and 9.175 dB. For the purpose of increasing the gain of an amplifier, the proposed LNA design was then optimized by using Wilkinson Power Divider (WPD). The Balanced LNA design using WPD offered very low noise figure of 0.422 dB and 0.532 dB respectively and the gain was considerably increased and was found to be 20.087 dB and 17.832 dB respectively against 2.1 GHz and 2.49 GHz. Simulations and measurements were taken in Agilent Advanced Design System (ADS) software. The suggested LNA can be used for a variety of wireless communications applications including the future S band satellite navigation systems.