Mixers

Mixers are very complicated, given three ports, wide frequency
disparities, time-varying switching devices, and simultaneous presence
of small and strong signals. Mixer literature is rife with details and
specific examples but sparse on the perspective and context presented
in this lecture. 

Topics include the definitions, methods, and motivations for
balancing a mixer, supression of spurious outputs, the four sources
of mixer nonlinearity, and the difference between LO and switching 
function waveforms. 

Quotes one veteran mixer designer, "Mixer designers will always have a job. 
There is always a problem to solve".