Monolithic integrated LNAs in silicon-based bipolar technologies

Receiving of weak signals in wireless applications demands for low-noise amplifiers with low noise figure around the carrier frequency. The enhanced potential of advanced silicon technologies for integrated LNAs is investigated. Silicon (including Si/SiGe) technologies are shown to offer LNA function with noise figures of about 1 dB in the region up to about 2 GHz used for mobile communications. For frequencies around 10 GHz a 50 Ω noise figure of 2 dB is presented with gain of >20 dB in a 0.5 μm/80 GHz Si/SiGe bipolar technology. From these excellent results in gain and noise, it can be expected that silicon-based RF technologies will also fulfill the requirements of future systems at higher frequency bands (e.g. of WLANs at 17.2 GHz, radio links up to 23 GHz, eventually even LMDS at 28 GHz), enabling the realization of completely monolithically integrated receivers and transceivers in low-cost silicon production technologies