  An important device for modulation and frequency translation in the field of
circuit quantum electrodynamics is the IQ mixer, an analog component for which
calibration is necessary to achieve optimal performance. In this paper, we
introduce techniques originally developed for wireless communication
applications to calibrate upconversion and downconversion mixers. A Kalman
filter together with a controllable carrier frequency offset calibrates both
mixers without removing them from the embedding measurement infrastructure.
These techniques can be embedded into room temperature control electronics and
they will find widespread use as circuit QED devices continue to grow in size
and complexity.
