Abstract
This letter presents an ultrawideband low-noise amplifier (LNA) incorporating stage-decoupled pole-shaping (SDPS) inductors. The bandwidth (BW) of each amplification stage is extended through independent RC feedback networks. In addition, the SDPS inductors introduce two controllable poles. These poles can be tuned to achieve pole shifting and peak staggering, which extend the operating bandwidth in a co-optimized manner. The resistive loads are employed to simplify interstage and output matching networks, achieving ultrawideband matching while maintaining a highly compact core layout. The proposed LNA is fabricated using the HHGRACE 0.18- \mu m SiGe BiCMOS process, achieving a bandwidth of 0.5-18 GHz [189.2% fractional bandwidth (FBW)], a peak gain of 21.5 dB, a noise figure (NF) performance in terms of noiseof 1.67-2.34 dB, an output 1-dB compression point (OP {}_{1\,\text {dB}} ) of 5.97 dBm at 8 GHz, a dc power consumption of 33.2 mW under a 3.3 V supply voltage, and a core area of only 0.07 mm 2 .