28 GHz Off-the-Shelf Low Noise Amplifier for 5G Baseband Wireless System

Abstract

This paper presents the simulation and measured results of a Low Noise Amplifier (LNA) working at 28 GHz for the 5G wireless system. LNA is used to amplify the weak receiving signals in the RF receiver system. The 28 GHz (Ka-band) LNA is designed to work for 5G technology wireless system. Here a Fujitsu FHR02X transistor is used in the simulation process, where the one-stage LNA is adopting a common-source with source inductive degenerative topology.In the fabrication process, GaAs pHEMT MMIC HMC519LC4 LNA is mounted on the Rogers 4003C board (εr = 3.38 and δ = 0.0027)and tested using (PNA-X N5246A) Microwave Network Analyzer. The final LNA design in the simulation process achieves a power gain of 9.185 dB, input and output return losses of – 13.124 dB and – 15.455 dB respectively, and noise figure of 9.185 dB. Furthermore, the fabricated LNA achieves a power gain of 10.91 dB, input and output return losses of - 7.75 dB and - 22.13 dB respectively. Although the return loss (S11) value is higher than -10 dB, but the LNA still able to obtain gain more than 10 dB.Thesimulation and fabricated LNA have input return loss quite closed to the given value in the datasheet. Thus, the LNA transmission line has a good output matching design.