The Research Of RF Receive Technology

With the wireless communication technologies being greatly developed in recent years, low-cost, low power consumptions, and high integration devices and circuits are being greatly reqiured. In these circuits, the integration of RF front-end circuit is the most difficult to implement. SiGe HBT not only has the same low cost and high density as Si device, but has the same high frequency performance as GaAs, so SiGe HBT and its integrated circuit are being applied widely in wireless telecommunication. The main work of this paper concentrates on SiGe HBT low noise amplifier.Based on analysis on wireless receivers and characteristic of IC components, this paper emphasizes on the analyses of the LNA performances: matching, noise figure, linearity, stability, and a new wide band matching method is introduced. Using the theory and method put forward in this paper, two 0.35 SiGe LNA circuits are designed and simulated. In LNA I , a LC-ladder filter technology was used to achieve the bandwidth from 1GHz to 1.65GHz. The LNA has a worse case noise figure (NF) of 2.45dB. LNA II can achieve three different gain mode and noise figure (NF) less than 1.6dB. Finally, this paper introduces the LNA layout and summaries the keystone of the RF layout.