[mistercheph]

I think common mode filtering in balanced audio cables is a much better analogy than noise canceling headphones (and where this paper gets its name from I assume), you don't know what the noise is ahead of time, but if you take two samples with one positive and one negative, noise displaces both absolutely, which you can take advantage of to denoise the signal (find the differential mode).

For example, if you are trying to send a +1V signal on one wire, and a -1V signal on the other and a +0.5V noise exists, one wire will have +1.5V and the other will have -0.5V,

Take the difference and divide by 2:

(+1.5V - -0.5V) / 2 = +1V or, if your setup is different (-0.5V - +1.5V) / 2 = -1V