Modeling and characterization of HBT transistor and its application to EBG multiband antenna

Abstract

This thesis involves the small-signal, large-signal, noise modeling and characterization of HBT for the application of multi-band active integrated slot antenna with novel EBG feed. The uniqueness of our approach is that it determines the parameters of small-signal model by the bi-directional optimization technique. Moreover, a new method to extract the thermal resistance is proposed and verified. The planar circuit approach and resonance-mode technique are extended to investigate the HBT parasitic inductive effect and its determination. The wave approach combined with contour-integral method is applied to analyze the HBT noise properties. A method to determine the equivalent noise temperature by using HBT small-signal model and minimum noise figure is suggested. This work also presents an empirical modification on the VBIC avalanche model valid up to the high current breakdown region. Finally, a novel feeding technique is proposed to simultaneously improve the impedance bandwidth of multi-band slot antenna.