Sige High - Linearity Research And Design Of Low Noise RF Amplifier

SiGe process is widely used in areas such as mobile communication, satellite location and radar tracing because of its high performance and cost-performance ratio. It's easy for SiGe process to integrate with RF, digital and analog circuits on a chip, forming an entire SoC. More and more RF ICs are fabricated with SiGe process now.With the rapid growth of the modern wireless communications, more and more communication capacities are required. In order to realize higher data velocity and much frequency efficiency, modern communication system adopts linear modulation technique. However, linear modulation will make circuits very sensitive to any non-linear factors. Therefore, proper linearizing techniques must be used to improve the linearity of the circuits, making the system could work regularly during linear modulation. So, linear amplifiers become a research highlight. As the first stage of a wireless receiver, low noise amplifier (LNA) must do more than simply amplify signals without adding much noise. It must remain linear even when strong signals are being received. In particular, the LNA must maintain linear operation when receiving a weak signal in the presence of a strong interfering one; otherwise, a variety of pathologies may result. Therefore, the study of higher liner RF LNAs has important practical significance. This thesis focused just about on the study and design of the higher liner LNA based on the advanced SiGe process.On the basis of numerous references, this thesis researched various LNA linearizing methods thoroughly; compared the advantages and disadvantages of them; and then modified the active bias technique as well as developed the formula derivation. During the formula derivation, the infinitesimal concept from Advanced Mathematics had been introduced into and the formula was expanded by Taylor series instead of omiting the infinitesimal term directly, making the derivation more persuadable. The conclusions as well as the linearizing idea have significant guiding meanings.The pre-simulation of the LNA circuit principles, layout design, extraction of parasitic parameters, post-simulation and optimization of the layout were all accomplished. The die size of the SiGe high liner LNA is 0.05mm2. The power gain S21 is 21.46dB at 1.34GHz with a gain flatness of ?0.37dB between 1.28GHz and 1.4GHz. The NF is 1.27dB at 1.34GHz and keeps below 1.32dB over the entire band. Return loss S11 is well below ?13.33dB and S22 is better than ?8.93dB. The IP1dB is ?11.52dBm. The power dissipation of the LNA is merely 10mA from a 3.3V supply. It is indicated that the simulated results meet the requirement of the target.