A 3.3 to 11.3 GHz Differential LNA with Slight Imbalance Active Balun in 0.15-μm GaAs pHEMT Process for Radio Astronomical Receiver

This paper presents a fully-integrated broadband, low noise amplifier (LNA) with differential input and single-ended output for radio astronomical receiver. The inductive source degeneration is adopted to minimizing the noise figure, the negative feedback is applied for broadband design, and the fully on chip matrix balun is introduced behind the third-stage. The 3-dB bandwidth of the DLNA covers from 3.3 to 11.3 GHz. The measurement results demonstrate peak gain of 28.3 dB, average noise figure of 1.4 dB with DC power consumption of 85 mW. The chip area of the amplifier is 3 × 2 mm².