Research And Design Of SiGe HBT Ultra-Wideband Low Noise Amplifier

With a high cut-off frequency fT, silicon germanium (SiGe) heterojunction bipolartransistors (HBT) have the properties of producing very low noise and high gain over awide bandwidth. Because of these properties, SiGe HBTs have continually improvedand now could compete with InP and GaAs HEMTs in radio and microwave frequencyintegrated ciruits applications. These advanced CMOS and SiGe BiCMOS technologyhave enabled complete silicon-based RF integrate circuit(RFIC) solutions for emergingwireless communication; indeed,both the analog and digital functionalities of an entirewireless system can now be combined in a single IC. The Low Noise Amplifier(LNA) isa key module in wireless communication system, whose performance determines thewhole receiver system directly. Based on SiGe BiCMOS process, this paper investigatethe design of SiGe HBT Ultra-Wideband(UWB) Low Noise Amplifer.First of all, the development of SiGe HBT and SiGe LNA application is introduced.The theoretical characterization of SiGe HBT is investigated by a comprehensive studyof the DC and small-signal transistor modeling. Based on a selected small-signal model,a noise model for the SiGe HBT transistor is produced. The noise performance of SiGeHBT is also discussed.Then, a qualitative analysis is carried out on primary parameters determining theperformance of LNA. Besides, the analysis and comparison between four commonUWB LNA structures is made.At last, based on Jazz0.18μm SiGe BiCMOS process, this thesis designs anUltra-Wideband Low Noise Amplifier by combining the π matching network withresistive-feedback structure, which can operate across a wide range frequency includingX band and Ku band. A detailed design flow, which includes calculation, pre-simulation,layout design, layout optimization, parasitic parameters extraction and post-simulationwith Cadence Spectre RF and Calibre, is proposed. The post-simulation results showthat the UWB LNA can achieve an input matching better than-11dB, a noise figureunder3dB, a power gain of20.3dB with variation less than1.6dB in the whole band.Thus, this amplifier works well and achieves the system specification.