[IEEE 2018 IEEE International Symposium on Radio-Frequency Integration Technology (RFIT) - Melbourne, Australia (2018.8.15-2018.8.17)] 2018 IEEE International Symposium on Radio-Frequency Integration Technology (RFIT) - A Fully-Integrated <tex>$S$</tex>-Band Differential LNA in <tex>$0.15-\mu \mathrm{m}$</tex> GaAs pHEMT for Radio Astronomical Receiver

摘要： A fully-integrated S-band high-gain MMIC low noise amplifier (LNA) with differential input and single-ended output is presented and implemented in 0.15-μm GaAs pHEMT for Square Kilometre Array (SKA) astronomical receiver. The low-loss input noise matching network is designed, and the fully on-chip LC balun is introduced between the first stage LNA core and the second stage amplifier to improve overall system noise figure. The 1-dB bandwidth of the LNA covers from 1.5 to 3.7 GHz. The measurement results demonstrate 31.8-dB gain, average in-band noise figure of 0.73 dB with DC power con- sumption of 25 mW. The chip area is 2.5 x 2 mm2. Also, a noise figure measurement method for the 3-port differential-input-to- single-ended-output amplifiers is introduced in this paper.