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Title: A Study on Design Methodologies of Power Amplifiers using SiGe BiCMOS Technology
Committee:
Dr. Cressler, Advisor
Dr. Ghovanloo, Chair
Dr. Wang
Abstract:
The goal of the proposed research is to develop multiple design methods of power amplifiers (PAs) using silicon germanium (SiGe) heterojunction bipolar transistor (HBT) to achieve highly efficient, high power, and/or broadband amplification. A PA is essential and the most crucial element in wireless transmitter because it consumes large power as heat and thus dominates the overall efficiency. To increase the output power of the PA, the large voltage and current swings are required, significantly affecting linearity as well as long term reliability. Demand for higher data rate wireless communication forces frequency spectrum move to either microwave or millimeter-wave (MM-wave) bands, which makes PA design cumbersome as there is a fundamental tradeoff between speed and breakdown of a transistor. All those design issues restrict use of cost-effective and large volume Si-based semiconductor technologies, including CMOS and SiGe HBT, for PA implementation. To overcome the limitations, we introduces multiple design strategies by exploiting SiGe HBT BiCMOS technology. To attain high output power and efficient operation concurrently, we proposed two types of X-band SiGe HBT cascode inverse-class F PAs with novel harmonic-tuned output matching networks. A low loss and broadband lumped-element Wilkinson power combiner is devised for wideband power amplifier. Also, a co-design method among a PA, a low noise amplifier, a single pole double throw (SPDT) switch is proposed to simultaneously optimize various design parameters. Based on the accomplishment, several future works are described to prove that SiGe HBT platform would be a viable solution in implementing PAs tailored to specific applications.
