Title :
Analysis and design of wide-band SiGe HBT active mixers
Author :
Johansen, Tom K. ; Vidkjær, Jens ; Krozer, Viktor
Author_Institution :
Sect. of Electromagn. Syst., Tech. Univ. of Denmark, Lyngby, Denmark
fDate :
7/1/2005 12:00:00 AM
Abstract :
The frequency response of SiGe HBT active mixers based on the Gilbert cell topology is analyzed theoretically. The time-varying operation of the active mixer is taken into account by applying conversion matrix analysis. The main bandwidth-limiting mechanisms experienced in SiGe HBT active mixers performing frequency conversion of wide-band signals is discussed. The analysis is verified by computer simulations using a realistic high-frequency large-signal SiGe HBT model. An active mixer design based on the Gilbert cell topology modified for wide-band operation using emitter degenerated transconductance stage and shunt feedback load stage is discussed. Experimental results are given for an active mixer implemented in a 0.8-μm 35-GHz fT SiGe HBT BiCMOS process.
Keywords :
Ge-Si alloys; bipolar MIMIC; frequency response; heterojunction bipolar transistors; millimetre wave mixers; 0.8 micron; 35 GHz; BiCMOS process; Gilbert cell topology; SiGe; active mixers; bandwidth-limiting mechanism; computer simulation; conversion matrix analysis; emitter degenerated transconductance; frequency conversion; frequency response; heterojunction bipolar transistor; shunt feedback load; time-varying operation; wide-band signals; Computer simulation; Frequency conversion; Frequency response; Germanium silicon alloys; Heterojunction bipolar transistors; Mixers; Silicon germanium; Topology; Transconductance; Wideband; Active mixer circuits; SiGe HBT; frequency-response analysis;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
DOI :
10.1109/TMTT.2005.850421
