Development of IEEE802.11a WLAN LNA in silicon-based processes

We describe the effects of substrate parasitics in silicon-based processes and present a methodology for designing low-noise amplifiers (LNAs) in silicon processes. Our techniques resulted in excellent agreement between simulations and measurements for a test case LNA design for 802.11a. This LNA, which covers 5-6 GHz and has gain switching is designed in a 0.8 μm SiGe bipolar technology with f/sub T/ of 50 GHz. The LNA exhibits a gain of more than 24 dB in the 5-6 GHz band with a noise figure (NF) less than 2.5 dB. The agreement between simulation and measured data is demonstrated.